Did X Cause Y? A New Look at Attributing Weather Extremes to Climate Change

By: Bob Henson , 4:01 PM GMT on March 15, 2016

In a world filled with high-impact weather events, it’s only natural to wonder exactly why your town was beset with a heat wave, a destructive flood, or a deadly tornado. Today, such events occur in a different global atmosphere--one with more greenhouse gases than at any time in human history, thanks to human activity. A growing branch of atmospheric research is working to quantify the influence of human-induced climate change on various types of extreme weather, and there is real progress being made. “It is now possible to estimate the influence of climate change on some types of specific weather events,” said Rear Admiral David Titley (Pennsylvania State University) at a press briefing in Washington, D.C., last Friday. Titley chaired a U.S. National Academies committee that has just produced an important report, released on Friday. Attribution of Extreme Weather Events in the Context of Climate Change serves as a very useful guide to how this work is carried out, what it can and can’t do, and where the science is heading.

The idea behind attribution research is to provide reasonably satisfying answers to the query so often raised by policy makers and the public: did climate change have anything to do with this event? For years, scientists rightly pointed out that a changing climate doesn’t “cause” any particular event. Often, they added that it was impossible to know exactly what role climate change might have played in a particular weather happening, apart from basic conclusions about how the physics of a warming atmosphere should make certain events increasingly more or less likely.

Things are different now, as pointed out by Titley, the founding director of PSU’s Center for Solutions to Weather and Climate Risk. Attribution research, said Titley, “makes the future of climate real. It brings the future into the present.”


Figure 1. A schematic depiction of the National Academies assessment of the state of attribution science for different event types. The horizontal position of each event type reflects the level of understanding of the effect of climate change on that event type, and corresponds to the rightmost column in Figure 2. The vertical position of each event corresponds to scientific confidence in current capabilities for attributing specific events of that type to anthropogenic climate change; this vertical position draws on all three columns in Figure 2. In all cases, there is potential to increase event-attribution confidence by overcoming remaining challenges that limit the current level of understanding. Image credit: National Academies.


Figure 2. An overall assessment of the state of event attribution science for various event types. In each category, the committee has provided an estimate of confidence, based on the available scientific literature and the results of committee deliberation and judgment. Image credit: National Academies.


A spectrum of understanding
While this report has some fairly technical content, including heavy-duty statistical concepts, most of the terminology is well explained up front. This follows in the tradition of reports from the National Academies that speak to a broad, policy-interested audience on emerging science topics of keen public interest. It was high time for this particular report, said committee member Marshall Shepherd (University of Georgia), a WU contributing blogger and host of the Weather Channel’s popular “WX Geeks” series. In the headline of a Forbes commentary published on Friday, Shepherd heralds “The Death to One of the Most Abused Questions Ever: Was That Caused by Climate Change?” He cites this question as “so abused by ALL sides of the climate discussion.”

The ideas underlying the new report are summarized nicely in Figure 1, which places a variety of extreme weather events on a twofold spectrum: how well the influence of climate change is understood, and how confidently we can attribute specific instances of that event to climate change. Figure 2 elaborates on Figure 1 for each event category. As one might expect, our confidence in attribution goes up as our understanding increases--but not all events line up on this straight line. Tropical cyclones are a good example. There is a growing body of research concluding that we can expect the frequency of the most intense storms to rise in many parts of the world, a finding reiterated by the IPCC in 2013. Several studies in the last decade have suggested this trend is already under way, especially in the Atlantic. Yet tropical cyclones remain rare enough that it is tough to disentangle natural variability and observational uncertainty from the actual impact of climate change. Top global models are just now gaining the skill and resolution to simulate trends in Category 4 and 5 hurricanes over centuries, or to embed individual storms such as Hurricane Sandy into global-scale models that replicate the climate of the distant past and our greenhouse-warmed future.


Figure 3. Three potential ways in which a warming climate could affect heat and cold extremes: (top) shifting the entire distribution of observed temperatures toward a warmer average; (middle) increasing the variability of the distribution; and (bottom) skewing the curve in one direction or the other. Image credit: National Academies.


Heat waves and cold waves provide the best-understood and most-straightforward links: as climate change proceeds, we can expect more extreme heat and less extreme cold, with occasional exceptions here and there. In many areas, we have a century or more of good-quality temperature data, and this helps smooth the way toward making solid attributions. “Heat waves and cold waves may be the best candidates for assessing the reliability and robustness of attribution methods,” says the report.

Severe convective storms--intense thunderstorms and the hail, wind, and tornadoes they spawn--rank lowest on the spectrum in Figure 1. That’s not to imply that these storms are necessarily immune to the influence of greenhouse gases. The point is that (a) such influences are not yet crystal clear, in part because of sampling and observing issues, and (b) the huge natural variability in severe weather makes it hard to pluck out a climate-change signal for a particular storm. There is intriguing progress being made in these areas, though, some of which I’ll be covering in a future blog based on a meeting I attended last week at Columbia University (the 2nd Workshop on Severe Convection and Climate).


Figure 4. A man walks along the heavily damaged beach on November 2, 2012, in the Rockaway neighborhood of Queens, New York City, following the devastating arrival of Hurricane Sandy. Image credit: Spencer Platt/Getty Images.

Asking the right question
In order to study an attribution problem in a useful way, one needs to know exactly what the goal is. “Statements about attribution are sensitive to the way the questions are posed and the context within which they are posed,” the report notes. “For example, a scientific researcher might re-pose the question ‘was Hurricane Sandy caused by climate change?’ as ‘by how much did human influence on climate increase the odds of a tropical or post-tropical storm with winds greater than 65 knots making landfall in northern New Jersey?’”

Once a well-posed question is in hand, there’s a growing toolbox of techniques for researchers to draw on, amply discussed in the report. Many attribution studies include a mix of observations and model-based simulations, with the goal of determining how much more likely a certain type of event has become (such as a heat wave of a particular strength over the Midwest) due to the presence of human-produced greenhouse gases.

The most familiar source of attribution research for many of us is the dozens of studies compiled each year since 2012 in special issues of the Bulletin of the American Meteorological Society. These studies are useful in many ways, the report notes, but they shouldn’t be taken as a collective assessment of how climate change affects the whole gamut of extreme weather. For example, there is a selection bias at work. These reports focus on the highest-impact weather of a given year, so if a particular type of event has become increasingly rare (say, mammoth citrus-killing freezes in Florida), it’s much less likely to get examined.

Why the cookie crumbles
I helped take a very informal stab at an attribution spectrum in 2012 while part of the communications group at the University Corporation for Atmospheric Research. For this special project, we found ourselves touching on some of the questions of framing, phrasing, and methodology that are dissected much more thoroughly in this report. It’s encouraging to see how much the discipline has been growing, and how much vital knowledge it will be able to generate with the appropriate level of support and focus. The National Academies report should go a long way toward the “mainstreaming” of attribution research. It will also help journalists, educators, and others who need to put this often-esoteric science into terms that people can easily grasp. The links between greenhouse gases and extreme weather are far too important and intricate to be dismissed or broad-brushed.

Consider this tasty analogy provided by David Titley: we can think of a freshly-baked cookie as a weather event, with the ingredients being the factors that aligned to cause the event (i.e., large-scale atmospheric features), and the baking surface and the oven temperature representing conditions in which the event occurred (i.e., increasing greenhouse gases, decreasing sea ice). “When you bite into a cookie and it doesn’t taste right,” said Titley, “it can be hard to determine what went wrong.”

You can download a PDF of the full report at the National Academies website. Jeff Masters will be back on Thursday with coverage of NOAA’s highly anticipated report on global climate for February. See our report from this past weekend on NASA’s blockbuster data.

Bob Henson


The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.

Reader Comments

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320. Climate175
9:15 PM GMT on March 17, 2016
.
Member Since: December 31, 1969 Posts: Comments:
319. Naga5000
4:47 PM GMT on March 17, 2016
Quoting 317. Barefootontherocks:

Perhaps what is now commonly referred to "climate change" needs a new and different name. Or maybe go back to global warming - which makes more sense and differentiates the current usage of the words "climate change" in a much better way. If the climate is changing over a period (30 years isn't it?) then weather is causing that. Temperature itself is simple weather. Of course, the seas must be brought into the picture is global surface temps are the monitoring goal. Right? Anyway, I hope you get my drift. The phrase, "climate change," in its current usage has two different meanings. And your usage of the phrase is not proven to cause extreme weather.

"Unattributed changes in weather"??? LOL Now that's a good one. Weather changes constantly. You might want to (re)read Admiral Titley's analogy above. So many unknowns... Try throwing in a little baking soda.

Extreme weather has happened since the atmosphere began. Still no proven causality. A high chance where temps are concerned. A medium to low to scratch your head chance of the others. I refer you to this graphic from the blog above.



I do not misuse words. Again, I am not confused. I am capable of seeing words and clouds and life in general in ways that you can't understand right now. That's all. Tell you what. I won't call your tunnel vision "confused" if you'll quit using that word for my way of thinking. From now on, when I see you or others exaggerating the science, I will call you on it thusly: "Leeches."
;)


What a bunch of gibberish. First, starting with the "go back to global warming" bit is a typical denier talking point that is completely unreal. Global warming is the term for the observed increase in temperature attributed to humans, climate change is the resulting atmospheric change as a consequence. Are you following yet?

"The argument "they changed the name" suggests that the term 'global warming' was previously the norm, and the widespread use of the term 'climate change' is now. However, this is simply untrue. For example, a seminal climate science work is Gilbert Plass' 1956 study 'The Carbon Dioxide Theory of Climatic Change' (which coincidentally estimated the climate sensitivity to a doubling of atmospheric carbon dioxide at 3.6%uFFFDC, not far off from today's widely accepted most likely value of 3%uFFFDC). Barrett and Gast published a letter in Science in 1971 entitled simply 'Climate Change'. The journal 'Climatic Change' was created in 1977 (and is still published today). The IPCC was formed in 1988, and of course the 'CC' is 'climate change', not 'global warming'. There are many, many other examples of the use of the term 'climate change' many decades ago. There is nothing new whatsoever about the usage of the term.

And a Google Scholar search reveals that the term 'climate change' was in use before the term 'global warming', and has always been the more commonly-used term in scientific literature":



The rest of your post is just nonsensical insult that somehow you are more knowledgeable than both the scientists (I suppose you are publishing your contrarianism, right?) and myself because of your magical way of thinking when in reality you just seem to enjoy being contrarian for the sake of being contrarian despite an ever increasing wrongness. By the way, have you managed to figure out why the trend wouldn't change if the baseline used for the graphs was different yet? It is certainly easy to ignore reality when you change the definitions to fit your own interpretation. Unfortunately, that doesn't play well in the real word.
Member Since: December 31, 1969 Posts: Comments:
318. Barefootontherocks
4:32 PM GMT on March 17, 2016
Quoting 306. Neapolitan:

The good news is that the numbers dropped. The bad news is that, even with the rains from last week's atmospheric river, drought conditions still prevail. Not that that should come as a shock: for months hydrologists have been telling us that California's water deficit could be measured not in inches but in feet and meters, and that even a few nice storms that dumped many inches weren't going to do more than put a few dents in the situation. Here's a current chart with this week's numbers incorporated:



Of course, the numbers will drop a bit more over the next few weeks as last week's rains are accounted for--but absent something big and unexpected happening, California is still in deep, deep trouble. In other words, not only is the state already back in dire straits, it never even left them...
Killjoy.

Drought like this does not go away in a single rainy season. Or even two, most times. You know that, Neo.
The improvement is easier to visualize this way - for me and others.
This week:

10-28-14:
Member Since: December 31, 1969 Posts: Comments:
317. Barefootontherocks
4:18 PM GMT on March 17, 2016
Quoting 314. Naga5000:



You are, you are confusing climate change for climate (or change in climate) and thereby suggesting an impossible relationship. I laid it out quite clear. The terms are well defined, climate change "refers to a change of climate that is attributed directly or indirectly to human activity that alters the composition of the global atmosphere and that is in addition to natural climate variability observed over comparable time periods." (UNFCC) Using that understanding, climate change (X) alters the atmosphere thereby effecting the weather (Y). The resulting effect can be measured as climate, and the difference between that climate and previous can be quantified as a change in climate. The average of weather over a time period is indeed climate, Barefoot, and while that relationship is quite real, is does not mean that unattributed changes in weather cause climate change. There must be a mechanism of action that causes the weather to change it does happen by magic or by non linear thinking...

In your example, weather (X) causes climate change (y). A more correct understanding is that weather averaged over a time period is climate and the resulting difference when compared to other climatic norms is a change in climate (not climate change as in the above definition). Again you are either misusing terminology or confused. Also your veiled insults are not appreciated.
Perhaps what is now commonly referred to "climate change" needs a new and different name. Or maybe go back to global warming - which makes more sense and differentiates the current usage of the words "climate change" in a much better way. If the climate is changing over a period (30 years isn't it?) then weather is causing that. Temperature itself is simple weather. Of course, the seas must be brought into the picture is if global surface temps are the monitoring goal. Right? Anyway, I hope you get my drift. The phrase, "climate change," in its current usage has two different meanings. And your usage of the phrase is not proven to cause extreme weather.

"Unattributed changes in weather"??? LOL Now that's a good one. Weather changes constantly. You might want to (re)read Admiral Titley's analogy above. So many unknowns... Try throwing in a little baking soda.

Extreme weather has happened since the atmosphere began. Still no proven causality. A high chance where temps are concerned. A medium to low to scratch your head chance of the others. I refer you to this graphic from the blog above.



I do not misuse words. Again, I am not confused. I am capable of seeing words and clouds and life in general in ways that you can't understand right now. That's all. Tell you what. I won't call your tunnel vision "confused" if you'll quit using that word for my way of thinking. From now on, when I see you or others exaggerating the science, I will call you on it thusly: "Leeches."
;)
Member Since: December 31, 1969 Posts: Comments:
316. WunderAlertBot (Admin)
3:53 PM GMT on March 17, 2016
JeffMasters has created a new entry.
315. MahFL
3:45 PM GMT on March 17, 2016
Quoting 296. ricderr:



notice california......yes...there lakes are filling up....but even with el nino the snowpack is at about 85 percent of normal......they could easily be back to dire straights in a couple of years


Ave is actually 90%. Also a lot of earlier snow has melted and filled up the reservoirs.
Member Since: December 31, 1969 Posts: Comments:
314. Naga5000
3:35 PM GMT on March 17, 2016
Quoting 311. Barefootontherocks:

Oh heck. I am not confused. Just capable of thinking in more than a straight line. Without weather, you cannot have climate. If you don't understand that, look up the definitions of the two words.


You are, you are confusing climate change for climate (or change in climate) and thereby suggesting an impossible relationship. I laid it out quite clear. The terms are well defined, climate change "refers to a change of climate that is attributed directly or indirectly to human activity that alters the composition of the global atmosphere and that is in addition to natural climate variability observed over comparable time periods." (UNFCC) Using that understanding, climate change (X) alters the atmosphere thereby effecting the weather (Y). The resulting effect can be measured as climate, and the difference between that climate and previous can be quantified as a change in climate. The average of weather over a time period is indeed climate, Barefoot, and while that relationship is quite real, is does not mean that unattributed changes in weather cause climate change. There must be a mechanism of action that causes the weather to change it does happen by magic or by non linear thinking...

In your example, weather (X) causes climate change (y). A more correct understanding is that weather averaged over a time period is climate and the resulting difference when compared to other climatic norms is a change in climate (not climate change as in the above definition). Again you are either misusing terminology or confused. Also your veiled insults are not appreciated.
Member Since: December 31, 1969 Posts: Comments:
313. Jedkins01
3:32 PM GMT on March 17, 2016
Quoting 309. weathermanwannabe:

Here is the link and chart from USGS on national ground water depletion issues; note from the other information posted this morning that salt-water contamination is an issue in many coastal regions including California and Florida:

http://water.usgs.gov/edu/gwdepletion.html

Map of groundwater depletion in certain aquifers in the U.S., showing depletion from 1900 to 2008, in feet.

Despite Florida's shallow bedrock, sandy soil that is poor at holding water, shallow bedrock, a lot of agriculture and a huge population, it seems to be doing fine for the most part according to that source.
Member Since: December 31, 1969 Posts: Comments:
312. barbamz
3:20 PM GMT on March 17, 2016

Yesterday's hard rime on a cross on top of Pratomagno mountains, Tuscany, Italy. Not much of spring down there, yet. (Here for comparison a video of that cross, at 1:45, from earlier this year when the region was in a severe drought.)
Member Since: December 31, 1969 Posts: Comments:
311. Barefootontherocks
3:13 PM GMT on March 17, 2016
Quoting 297. Naga5000:



Incorrect, a changing climate system modifies the parameters for weather events, those weather events over time create an average climate which is different from the previous (that average climate is what we measure, climate change is the term for the modified parameters that influence weather). You are confusing terms.
Oh heck. I am not confused. Just capable of thinking in more than a straight line. Without weather, you cannot have climate. If you don't understand that, look up the definitions of the two words.
Member Since: December 31, 1969 Posts: Comments:
310. cRRKampen
2:17 PM GMT on March 17, 2016
Quoting 302. OKsky:



Actually if the dream is about an alternative reality where natural science is the same as political science and weather happens in ziplock baggies in isolation from effects of climate, I think "wake up" might be a better thing to do than "dream on". =P

It works like 'don't think of a baby pink elephant' ;)
Member Since: December 31, 1969 Posts: Comments:
309. weathermanwannabe
2:10 PM GMT on March 17, 2016
Here is the link and chart from USGS on national ground water depletion issues; note from the other information posted this morning that salt-water contamination is an issue in many coastal regions including California and Florida:

http://water.usgs.gov/edu/gwdepletion.html

Map of groundwater depletion in certain aquifers in the U.S., showing depletion from 1900 to 2008, in feet.
Member Since: December 31, 1969 Posts: Comments:
308. Neapolitan
2:09 PM GMT on March 17, 2016
Quoting 284. Sandy82579:

Let's not do this kind of stuff. Isolated weather events can never be tied to the long term effects of climate change.
Let's not do *what* kind of stuff? Would you have us follow non-scientific proclamations based on nothing more than denial, ideology, or wishful thinking? Should we not instead hew to that which the greatest minds, equipped with the deepest knowledge and the most advanced technology, are telling us? This is America, of course, so everyone is free to their own opinion no matter how absolutely wrong that opinion is. But opinion is not fact, and fact is not opinion, and never the twain shall meet. Go with the former if it brings you comfort. But I do believe I'll side with science on this one.
Member Since: December 31, 1969 Posts: Comments:
307. hydrus
2:08 PM GMT on March 17, 2016
Member Since: December 31, 1969 Posts: Comments:
306. Neapolitan
2:00 PM GMT on March 17, 2016
Quoting 296. ricderr:



notice california......yes...there lakes are filling up....but even with el nino the snowpack is at about 85 percent of normal......they could easily be back to dire straights in a couple of years
The good news is that the numbers dropped. The bad news is that, even with the rains from last week's atmospheric river, drought conditions still prevail. Not that that should come as a shock: for months hydrologists have been telling us that California's water deficit could be measured not in inches but in feet and meters, and that even a few nice storms that dumped many inches weren't going to do more than put a few dents in the situation. Here's a current chart with this week's numbers incorporated:



Of course, the numbers will drop a bit more over the next few weeks as last week's rains are accounted for--but absent something big and unexpected happening, California is still in deep, deep trouble. In other words, not only is the state already back in dire straits, it never even left them...
Member Since: December 31, 1969 Posts: Comments:
305. washingtonian115
1:59 PM GMT on March 17, 2016
Euro has 7-9 inches for D.C.The good news is that the sun angle will get rid of it in no time considering we are nearing April.
Member Since: December 31, 1969 Posts: Comments:
304. washingtonian115
1:50 PM GMT on March 17, 2016
Ryan Maue ‏@RyanMaue 6h6 hours ago
ECMWF 00z w/blizzard on Monday for New England. Major snowfall from DC --> NYC -> Boston starting late Sun --> Mon

I was hoping for a track out to sea on the over night models.
Member Since: December 31, 1969 Posts: Comments:
303. weathermanwannabe
1:43 PM GMT on March 17, 2016
Quoting 300. cRRKampen:


Hugely so.
Families should move out before it becomes a flight.


From the Governor's April 2015 executive order:


EXECUTIVE ORDER B-29-15
WHEREAS on January 17, 2014, I proclaimed a State of Emergency to exist
throughout the State of California due to severe drought conditions; and
WHEREAS on April 25, 2014, I proclaimed a Continued State of Emergency
to exist throughout the State of California due to the ongoing drought; and
WHEREAS California's water supplies continue to be severely depleted
despite a limited amount of rain and snowfall this winter, with record low snowpack
in the Sierra Nevada mountains, decreased water levels in most of California's
reservoirs, reduced flows in the state's rivers and shrinking supplies in underground
water basins; and
WHEREAS the severe drought conditions continue to present urgent
challenges including: drinking water shortages in communities across the state,
diminished water for agricultural production, degraded habitat for many fish and
wildlife species, increased wildfire risk, and the threat of saltwater contamination to
fresh water supplies in the Sacramento-San Joaquin Bay Delta; and
WHEREAS a distinct possibility exists that the current drought will stretch into
a fifth straight year in 2016 and beyond; and

Member Since: December 31, 1969 Posts: Comments:
302. OKsky
1:42 PM GMT on March 17, 2016
Quoting 289. cRRKampen:


Dream on.


Actually if the dream is about an alternative reality where natural science is the same as political science and weather happens in ziplock baggies in isolation from effects of climate, I think "wake up" might be a better thing to do than "dream on". =P
Member Since: December 31, 1969 Posts: Comments:
301. weathermanwannabe
1:36 PM GMT on March 17, 2016
As already noted today, if you live anywhere from the Texas to Alabama corridor
where the t-storms are coming through, you might want to consider parking your
vehicles under some type of shelter (if you can) in case some of the stronger cells
start dropping hail:

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0743 AM CDT THU MAR 17 2016

VALID 171300Z - 181200Z

...THERE IS A SLGT RISK OF SVR TSTMS TODAY FROM E TX TO SW AL...

...THERE IS A MRGL RISK OF SVR TSTMS TODAY FROM N CENTRAL AND SE TX
EWD TO SE AL AND THE FL PANHANDLE...

...THERE IS A MRGL RISK OF SVR TSTMS THIS AFTERNOON FOR PART OF NEW
ENGLAND...

...SUMMARY...
A FEW SEVERE STORMS WITH LARGE HAIL ARE EXPECTED FROM EASTERN TEXAS
TO SOUTHERN ALABAMA TODAY. OTHER STRONG STORMS WITH GUSTY WINDS AND
SMALL HAIL MIGHT OCCUR OVER A PORTION OF NEW ENGLAND.


...N CENTRAL AND E TX TO THE N CENTRAL GULF COAST TODAY...
A COUPLE OF ELEVATED THUNDERSTORMS...WITH SOME SUPERCELL
STRUCTURE...ARE ONGOING OVER N TX. THE CONVECTION IS ROOTED NEAR
850 MB...TO THE N OF A SLOW-MOVING FRONT. THE STORMS HAVE BEEN
SUPPORTED BY WEAK LOW-LEVEL WAA ABOVE THE FRONTAL SURFACE...AND BY
DIVERGENCE IN THE RIGHT ENTRANCE REGION OF THE UPPER JET THAT
EXTENDS FROM SE KS TO THE OH VALLEY. THIS ZONE OF FORCING FOR
ASCENT SHOULD SPREAD EWD-ESEWD ALONG THE STALLED FRONT THROUGH THE
DAY...WITH ADDITIONAL THUNDERSTORM DEVELOPMENT EXPECTED ALONG AND ON
THE IMMEDIATE COOL SIDE OF THE FRONT. MEANWHILE...MODERATE
INSTABILITY IS PRESENT S OF THE FRONT FROM CENTRAL/SE TX EWD ALONG
THE I-10 CORRIDOR. BOUNDARY LAYER DEWPOINTS OF 65-70 F BENEATH
MIDLEVEL LAPSE RATES NEAR 7 C/KM WILL RESULT IN MLCAPE VALUES OF
2000-2500 J/KG WITH SURFACE HEATING. THOUGH LOW-LEVEL FLOW WILL
REMAIN WEAK IN THE WARM SECTOR...DEEP-LAYER SPEED SHEAR AND STRAIGHT
HODOGRAPHS WILL SUPPORT OCCASIONAL SPLITTING SUPERCELL STRUCTURES.
LARGE HAIL WILL BE THE PRIMARY THREAT...AND ISOLATED VERY LARGE HAIL
WILL BE POSSIBLE ACROSS E TX AND CENTRAL LA.
Member Since: December 31, 1969 Posts: Comments:
300. cRRKampen
1:33 PM GMT on March 17, 2016
Quoting 298. weathermanwannabe:



Yup; that part of Cali has been in a drought slump for a few years now and this current El Nino has not made much of true dent with the exception of the snow pack issue; Cali is in trouble if this is part of a semi-permanent pattern change that remains in place over the long term.

Hugely so.
Families should move out before it becomes a flight.
Member Since: December 31, 1969 Posts: Comments:
299. Sfloridacat5
1:27 PM GMT on March 17, 2016
Quoting 297. Naga5000:



Incorrect, a changing climate system modifies the parameters for weather events, those weather events over time create an average climate which is different from the previous (that average climate is what we measure, climate change is the term for the modified parameters that influence weather). You are confusing terms.


I got very confused by that too.
(Independent variable -Climate Change) causes a change in (Dependent Variable- Weather Events) and it isn't possible that (Dependent Variable) could cause a change in (Independent Variable).


Member Since: December 31, 1969 Posts: Comments:
298. weathermanwannabe
1:20 PM GMT on March 17, 2016
Quoting 296. ricderr:



notice california......yes...there lakes are filling up....but even with el nino the snowpack is at about 85 percent of normal......they could easily be back to dire straights in a couple of years


Yup; that part of Cali has been in a drought slump for a few years now and this current El Nino has not made much of true dent with the exception of the snow pack issue; Cali is in trouble if this is part of a semi-permanent pattern change that remains in place over the long term.
Member Since: December 31, 1969 Posts: Comments:
297. Naga5000
1:14 PM GMT on March 17, 2016
Quoting 257. Barefootontherocks:

Thanks for this blog updating the latest on the latest thinking regarding this x>y "causality." Saved the colorful graphic because I think it is important to remember what the graphic does not show as well as what it shows. Admiral Titley's analogy is great and shows his understanding of weather as caused by the interactions that sometimes come out one way and other times other ways.

In another way of looking at the relationship between weather and climate,
if X = climate change (of whatever cause)
and Y = weather event(s)
then, Y causes X, not vice versa.


Incorrect, a changing climate system modifies the parameters for weather events, those weather events over time create an average climate which is different from the previous (that average climate is what we measure, climate change is the term for the modified parameters that influence weather). You are confusing terms.
Member Since: December 31, 1969 Posts: Comments:
296. ricderr
1:10 PM GMT on March 17, 2016
Quoting 291. weathermanwannabe:

The weekly US drought monitor for today; notice how the Gulf rains alleviated some of the dryness along Texas, LA, and other parts of the Northern Gulf coast but at a very high price and loss of life from the Mexican low situation and floodings:

Current U.S. Drought Monitor


notice california......yes...there lakes are filling up....but even with el nino the snowpack is at about 85 percent of normal......they could easily be back to dire straights in a couple of years
Member Since: December 31, 1969 Posts: Comments:
295. LargoFl
1:08 PM GMT on March 17, 2016
Just want to stop in and wish everyone a safe and Happy St.Patrick's Day ....
Member Since: December 31, 1969 Posts: Comments:
294. LargoFl
1:07 PM GMT on March 17, 2016
THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTH CENTRAL
ALABAMA...SOUTHWEST ALABAMA...NORTHWEST FLORIDA AND SOUTHEAST
MISSISSIPPI.

.DAY ONE...TODAY AND TONIGHT

A FEW STRONG TO SEVERE THUNDERSTORMS ARE POSSIBLE LATE THIS MORNING
THROUGH THE AFTERNOON HOURS. THE PRIMARY THREAT WILL BE LARGE HAIL
AND LOCALLY HEAVY RAIN.

SEVERAL AREA RIVERS ARE EXPERIENCING FLOODING....SEE THE LATEST
RIVER FORECAST FOR MORE INFORMATION.

THERE IS A MODERATE RISK OF RIP CURRENTS ALONG THE BEACHES OF
SOUTHWEST ALABAMA AND THE NORTHWEST FLORIDA PANHANDLE.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

SHOWERS AND THUNDERSTORMS WILL INCREASE IN COVERAGE THROUGH THE END
OF THE WEEK. SOME LOCALLY HEAVY RAIN IS POSSIBLE...ESPECIALLY IN
COASTAL LOCATIONS.

SEVERAL AREA RIVERS ARE EXPERIENCING FLOODING....SEE THE LATEST
RIVER FORECAST FOR MORE INFORMATION.

.SPOTTER INFORMATION STATEMENT...

ACTIVATION OF SKYWARN SEVERE STORM SPOTTER NETWORKS IS NOT
EXPECTED THROUGH WEDNESDAY.

$$
Member Since: December 31, 1969 Posts: Comments:
293. weathermanwannabe
1:05 PM GMT on March 17, 2016
Not a tornadic event today but hail in section of Texas so far this morning:

last3hours Filtered Reports Graphic
South Plains sector loop
Member Since: December 31, 1969 Posts: Comments:
292. LargoFl
1:02 PM GMT on March 17, 2016
already some bad storms............................................ .......SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOBILE AL
745 AM CDT THU MAR 17 2016

ALC035-099-171315-
/O.CON.KMOB.SV.W.0065.000000T0000Z-160317T1315Z/
CONECUH AL-MONROE AL-
745 AM CDT THU MAR 17 2016

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 815 AM CDT
FOR NORTH CENTRAL CONECUH AND NORTHEASTERN MONROE COUNTIES...

AT 744 AM CDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR MONROEVILLE...
MOVING NORTHEAST AT 20 MPH.

HAZARD...60 MPH WIND GUSTS AND QUARTER SIZE HAIL.

SOURCE...RADAR INDICATED.

IMPACT...HAIL DAMAGE TO VEHICLES IS EXPECTED. EXPECT WIND DAMAGE TO
ROOFS...SIDING...AND TREES.

LOCATIONS IMPACTED INCLUDE...
MONROEVILLE...BEATRICE AND PETERMAN.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
BUILDING.

PREPARE IMMEDIATELY FOR LARGE HAIL AND DEADLY CLOUD TO GROUND
LIGHTNING. SEEK SHELTER INSIDE A WELL-BUILT STRUCTURE. STAY AWAY FROM
WINDOWS.

&&

LAT...LON 3183 8715 3164 8694 3152 8732 3164 8745
3183 8723
TIME...MOT...LOC 1244Z 236DEG 18KT 3160 8735

HAIL...1.00IN
WIND...60MPH

Member Since: December 31, 1969 Posts: Comments:
291. weathermanwannabe
1:02 PM GMT on March 17, 2016
The weekly US drought monitor for today; notice how the Gulf rains alleviated some of the dryness along Texas, LA, and other parts of the Northern Gulf coast but at a very high price and loss of life from the Mexican low situation and floodings:

Current U.S. Drought Monitor
Member Since: December 31, 1969 Posts: Comments:
290. LargoFl
1:00 PM GMT on March 17, 2016
Stay Alert today folks along the northern gulf coast............................................. ...................DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0743 AM CDT THU MAR 17 2016

VALID 171300Z - 181200Z

...THERE IS A SLGT RISK OF SVR TSTMS TODAY FROM E TX TO SW AL...

...THERE IS A MRGL RISK OF SVR TSTMS TODAY FROM N CENTRAL AND SE TX
EWD TO SE AL AND THE FL PANHANDLE...

...THERE IS A MRGL RISK OF SVR TSTMS THIS AFTERNOON FOR PART OF NEW
ENGLAND...

...SUMMARY...
A FEW SEVERE STORMS WITH LARGE HAIL ARE EXPECTED FROM EASTERN TEXAS
TO SOUTHERN ALABAMA TODAY. OTHER STRONG STORMS WITH GUSTY WINDS AND
SMALL HAIL MIGHT OCCUR OVER A PORTION OF NEW ENGLAND.

...N CENTRAL AND E TX TO THE N CENTRAL GULF COAST TODAY...
A COUPLE OF ELEVATED THUNDERSTORMS...WITH SOME SUPERCELL
STRUCTURE...ARE ONGOING OVER N TX. THE CONVECTION IS ROOTED NEAR
850 MB...TO THE N OF A SLOW-MOVING FRONT. THE STORMS HAVE BEEN
SUPPORTED BY WEAK LOW-LEVEL WAA ABOVE THE FRONTAL SURFACE...AND BY
DIVERGENCE IN THE RIGHT ENTRANCE REGION OF THE UPPER JET THAT
EXTENDS FROM SE KS TO THE OH VALLEY. THIS ZONE OF FORCING FOR
ASCENT SHOULD SPREAD EWD-ESEWD ALONG THE STALLED FRONT THROUGH THE
DAY...WITH ADDITIONAL THUNDERSTORM DEVELOPMENT EXPECTED ALONG AND ON
THE IMMEDIATE COOL SIDE OF THE FRONT. MEANWHILE...MODERATE
INSTABILITY IS PRESENT S OF THE FRONT FROM CENTRAL/SE TX EWD ALONG
THE I-10 CORRIDOR. BOUNDARY LAYER DEWPOINTS OF 65-70 F BENEATH
MIDLEVEL LAPSE RATES NEAR 7 C/KM WILL RESULT IN MLCAPE VALUES OF
2000-2500 J/KG WITH SURFACE HEATING. THOUGH LOW-LEVEL FLOW WILL
REMAIN WEAK IN THE WARM SECTOR...DEEP-LAYER SPEED SHEAR AND STRAIGHT
HODOGRAPHS WILL SUPPORT OCCASIONAL SPLITTING SUPERCELL STRUCTURES.
LARGE HAIL WILL BE THE PRIMARY THREAT...AND ISOLATED VERY LARGE HAIL
WILL BE POSSIBLE ACROSS E TX AND CENTRAL LA.

...PARTS OF NEW ENGLAND THIS AFTERNOON...
COLD MIDLEVEL TEMPERATURES AND ASSOCIATED STEEP LAPSE RATES WILL
SUPPORT WEAK BUOYANCY WITH SURFACE HEATING...DESPITE RESIDUAL
BOUNDARY LAYER DEWPOINTS ONLY IN THE LOW 40S. A FEW SOMEWHAT
HIGH-BASED AND LOW-TOPPED THUNDERSTORMS COULD PRODUCE SMALL HAIL AND
GUSTY WINDS FOR A FEW HOURS THIS AFTERNOON...BUT ORGANIZED SEVERE
STORMS APPEAR UNLIKELY GIVEN THE LIMITED MOISTURE.

..THOMPSON/GLEASON.. 03/17/2016

Member Since: December 31, 1969 Posts: Comments:
289. cRRKampen
12:55 PM GMT on March 17, 2016
Quoting 284. Sandy82579:

From above - "In order to study an attribution problem in a useful way, one needs to know exactly what the goal is. %u201CStatements about attribution are sensitive to the way the questions are posed and the context within which they are posed,%u201D the report notes. %u201CFor example, a scientific researcher might re-pose the question %u2018was Hurricane Sandy caused by climate change?%u2019 as %u2018by how much did human influence on climate increase the odds of a tropical or post-tropical storm with winds greater than 65 knots making landfall in northern New Jersey?%u2019%u201D"

Manipulating questions to get the answer you want is dishonest and unethical. Just ask the question honestly and use the data it generates.

The worst pervision like this I've ever seen was on a ballot initiative in Ohio where if a voter voted "yes", they were actually voting "no" because of how the question was worded.

Let's not do this kind of stuff. Isolated weather events can never be tied to the long term effects of climate change.

Dream on.
Member Since: December 31, 1969 Posts: Comments:
288. HadesGodWyvern (Mod)
12:54 PM GMT on March 17, 2016
Mauritius Meteorological Services
Tropical Cyclone Advisory #9
Hurricane Warning
CYCLONE TROPICAL INTENSE EMERAUDE (06-20152016)
16:00 PM RET March 17 2016
===============================
Southeast of Diego Garcia

At 12:00 PM UTC, Intense Tropical Cyclone Emeraude (940 hPa) located at 10.7S 84.0E has 10 minute sustained winds of 105 knots with gusts of 150 knots. The cyclone is reported as quasi-stationary.

Hurricane Force Winds
===============
20 NM radius from the center, extending up to 25 NM in the northwestern quadrant

Storm Force Winds
============
25 NM radius from the center, extending up to 40 NM in the northwestern quadrant

Gale Force Winds
============
30 NM radius from the center, extending up to 60 NM in the northwestern quadrant

Near Gale Force Winds
=================
45 NM radius from the center, extending up to 50 NM in the southern semi-circle and up to 80 NM in the northwestern quadrant

Dvorak Intensity: T5.5/6.0/W1.0/6 HRS

Forecast and Intensity
===============
12 HRS: 10.9S 84.6E - 110 knots (Cyclone Tropical Intense)
24 HRS: 11.1S 85.7E - 110 knots (Cyclone Tropical Intense)
48 HRS: 11.9S 88.3E - 110 knots (Cyclone Tropical Intense)
72 HRS: 13.6S 89.2E - 90 knots (Cyclone Tropical Intense)

Additional Information
=================
The satellite presentation show that deep convection suffer from diurnal effect due to the small size of the system. The eye has slightly become larger, but remain very hot.

Emeraude seems to be quite stationary on the very last satellite imagery, and should turn gradually eastwards under the steering flow of a near equatorial ridge building in its northeast. During the weekend, the track should turn southwards then southwestwards as a subtropical ridge should gradually build south of the system. Global models are not in good agreement and differ sometimes strongly about the forward speed leading to significant spread in the guidance between them and also from one run to the other. The current forecast is close to the previous one and is a blend of the latest mean track from GFS-UKMO-EURO and GFS ( a less confidence has been given to the last run of EURO, as the intensity is to weak in the model) and the lack of stability of the numerical weather prediction data.

On this track, environmental conditions will remain mostly conducive during most of the forecast period. The system is located under an upper level ridge with a still improving upper level divergence polewards due to the remote effect of a transient upper level trough today and Friday. The environment could be a little less conducive later this weekend essentially due to an increase in northerly vertical wind shear. On the current forecast track, the system could pass over self-induced cool waters. Moreover, the internal dynamics, such as eyewall replacement cycle which is very likely with mature system but with poor forecast skill, could reduce the intensification rate. Given the small size of the system, rapid variation (including rapid intensification and rapid decay) are likely, bringing uncertainties in the forecast.
Member Since: December 31, 1969 Posts: Comments:
287. wunderkidcayman
12:43 PM GMT on March 17, 2016
Quoting 279. JRRP7:




Hmm at this rate would be suprised if we see 1.5 by next week or even as early as this weekend
1.0 by end of month 0.5 by mid April
Member Since: December 31, 1969 Posts: Comments:
285. DeepSeaRising
12:41 PM GMT on March 17, 2016
Did X cause Y? I look back over the last twenty years and have to conclude that the number of extreme events and rapid warming show clearly everything's connected on an energy level. It's just in different places at different times. Cause and effect of individual events is very hard. It's all connected though, and as I have seen over the last twenty years, it really is faster and faster now.
Member Since: December 31, 1969 Posts: Comments:
284. Sandy82579
12:29 PM GMT on March 17, 2016
From above - "In order to study an attribution problem in a useful way, one needs to know exactly what the goal is. %u201CStatements about attribution are sensitive to the way the questions are posed and the context within which they are posed,%u201D the report notes. %u201CFor example, a scientific researcher might re-pose the question %u2018was Hurricane Sandy caused by climate change?%u2019 as %u2018by how much did human influence on climate increase the odds of a tropical or post-tropical storm with winds greater than 65 knots making landfall in northern New Jersey?%u2019%u201D"

Manipulating questions to get the answer you want is dishonest and unethical. Just ask the question honestly and use the data it generates.

The worst pervision like this I've ever seen was on a ballot initiative in Ohio where if a voter voted "yes", they were actually voting "no" because of how the question was worded.

Let's not do this kind of stuff. Isolated weather events can never be tied to the long term effects of climate change.
Member Since: December 31, 1969 Posts: Comments:
283. Greg01
12:23 PM GMT on March 17, 2016
Quoting 267. pureet1948:



That's just it, Bucsboltsfan. I did read it and they seem to be a little bit vague about what real threat, if any, this new system poses to the area. I'm sure it's not going help the flood situation in far SE TX and LA, though. Accuweather's engaging in a little bit of doomcasting, I'm afraid. In short, nothing I'm finding on the web is helpful. So, I'm hoping y'all can be a tad more helpful, that's all. OK?

If our local NWS discussion is fairly benign, and they don't see a threat, then no one here is going to raise any flags of concern. Every passing cloud is not a cause for concern. I've lived in Houston most of my life and I have never experienced severe weather that was not mentioned as a threat by the local NWS. I also keep handy a handheld marine vhf radio that has all the weather bands and transmits 24/7.
Member Since: December 31, 1969 Posts: Comments:
282. weathermanwannabe
12:01 PM GMT on March 17, 2016
Look at how warm the waters are where Emeraude is traversing as well as the overall heat in the equatorial waters around the world:


global hires sst map


Member Since: December 31, 1969 Posts: Comments:
281. weathermanwannabe
11:54 AM GMT on March 17, 2016
And finally the latest on Emeraude in the Indian Ocean: thankfully not a threat to a any significantly populated areas. Impressive storm that underwent rapid intensification earlier today and up to 125 knots with further slow intensification forecast:

REMARKS:
170900Z POSITION NEAR 10.4S 84.0E.
TROPICAL CYCLONE 15S (EMERAUDE), LOCATED APPROXIMATELY 710 NM
EAST-SOUTHEAST OF DIEGO GARCIA, HAS TRACKED WEST-NORTHWESTWARD AT
02 KNOTS OVER THE PAST SIX HOURS. ANIMATED VISIBLE SATELLITE IMAGERY
DEPICTS DEEP SYMMETRIC CORE CONVECTION AND A VERY COMPACT 14 NM EYE
FEATURE, PROVIDING HIGH CONFIDENCE IN THE CURRENT POSITION. IN THE
PAST FEW HOURS, TC EMERAUDE HAS UNDERGONE A PERIOD OF VERY RAPID
INTENSIFICATION (RI) AND THE INITIAL INTENSITY HAS BEEN INCREASED TO
125 KNOTS BASED ON DVORAK INTENSITY ESTIMATES OF T6.5 (127 KNOTS)
FROM PGTW, KNES AND FMEE. UPPER-LEVEL ANALYSIS INDICATES TC EMERAUDE
CONTINUES TO TRACK IN A FAVORABLE ENVIRONMENT WITH LOW VERTICAL WIND
SHEAR (VWS) OF 10-15 KNOTS, A SOLID POLEWARD OUTFLOW CHANNEL, AND
WARM (28-29 CELSIUS) SEA SURFACE TEMPERATURES (SSTS). THE SYSTEM HAS
BECOME QUASI-STATIONARY OVER THE PAST SIX HOURS AS A NEAR-EQUATORIAL
RIDGE (NER) HAS BUILT IN TO THE NORTH. FAVORABLE CONDITIONS ARE
EXPECTED TO PERSIST FOR THE NEXT 24 HOURS AS AN UPPER-LEVEL POINT
SOURCE IS FORECAST TO DEVELOP OVER THE SYSTEM, SUPPORTING A FURTHER
SLOW INTENSIFICATION, LEADING TO A PEAK INTENSITY OF 135 KNOTS BY
TAU 24. AFTER TAU 36, THE SYSTEM WILL BEGIN A SLOW WEAKENING TREND
IN RESPONSE TO A DEGRADATION OF UPPER-LEVEL CONDITIONS AND LOWER
OCEAN HEAT CONTENT (OHC) VALUES. GENERALLY QUASI-STATIONARY MOVEMENT
IS FORECAST OVER THE NEXT 6-12 HOURS AS TC EMERAUDE BEGINS A SLOW
TURN TO THE SOUTH-SOUTHEAST UNDER THE INFLUENCE OF THE STRENGTHENING
NER TO THE NORTH. TC EMERAUDE IS EXPECTED TO PICK UP SPEED AND AFTER
TAU 12 AND ACCELERATE TOWARDS THE SOUTHEAST AS THE NER CONTINUES TO
STRENGTHEN. AFTER TAU 72, TC 15S WILL TURN BACK TO THE WEST AS THE
AFOREMENTIONED SUB-TROPICAL RIDGE REORIENTS AND DOMINATES THE
STEERING ENVIRONMENT. MODEL GUIDANCE IS NOT IN GOOD AGREEMENT AND
CONTINUES TO SHOW SIGNIFICANT TRACK DIRECTION AND SPEED VARIATION,
ESPECIALLY AFTER TAU 48. DUE TO THE COMPLEX STEERING ENVIRONMENT AND
UNCERTAINTY OF THE TIMING OF THE TURN, JTWC TRACK FORECAST
CONFIDENCE LEVEL REMAINS LOW. MAXIMUM SIGNIFICANT WAVE HEIGHT AT
170600Z IS 34 FEET. NEXT WARNINGS AT 172100Z AND 180900Z.//
NNNN






Member Since: December 31, 1969 Posts: Comments:
280. weathermanwannabe
11:42 AM GMT on March 17, 2016
And the current look, jet driving down colder air from the Northern latitudes into the mid-section of the US, and highs for today:

Graphic Forecast of Temperatures Across the US from the National Digital Forecast Database

Member Since: December 31, 1969 Posts: Comments:
279. JRRP7
11:40 AM GMT on March 17, 2016
Member Since: December 31, 1969 Posts: Comments:
278. weathermanwannabe
11:38 AM GMT on March 17, 2016
Good Morning; the short-term forecast for Conus today and some cold weather moving into a chunk of the US; Winter is not over yet.

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
349 AM EDT Thu Mar 17 2016

Valid 12Z Thu Mar 17 2016 - 12Z Sat Mar 19 2016

...Cooler weather returning to much of the country by the end of the
week...

...Unsettled weather expected for the Gulf Coast region...

A pattern change is underway that will result in colder weather across
much of the central and eastern U.S. by the end of the week. The front
that cleared the East Coast Wednesday night had a minor effect on
temperatures, while a secondary front forecast to move through by Friday
will have a more noticeable drop in temperatures. Highs will return to
near or slightly below average for this time of year for many locations by
this weekend.

Over the Upper Midwest, the surface low over the northern Great Lakes is
forecast to weaken and move towards the east. Some snow is likely on the
northern side of this low over northern Michigan and also into northern
New England. Windy conditions are also expected in the vicinity of the
surface low with a strong pressure gradient in place.

With a stationary front setting up near the Gulf Coast over the next
couple of days, along with shortwave energy passing overhead, showers and
thunderstorms are likely from southern Texas to the Florida panhandle. A
few inches of rain will be possible in those areas that see the most
persistent rainfall.


Member Since: December 31, 1969 Posts: Comments:
277. Tcwx2
11:28 AM GMT on March 17, 2016
A few thunderstorms look to be forming into a supercellular shape over southern Alabama. Rain for me today, yay!
Member Since: December 31, 1969 Posts: Comments:
276. HurricaneFan
10:48 AM GMT on March 17, 2016
Quoting 273. Gearsts:



Looks category 5 to me...
Member Since: December 31, 1969 Posts: Comments:
275. LargoFl
8:55 AM GMT on March 17, 2016
Member Since: December 31, 1969 Posts: Comments:
274. barbamz
8:20 AM GMT on March 17, 2016
A gorgeous good morning from Mainz!


NASA Earth Observatory got a new article about recent record warm February with this very telling chart:



Source: Record Warmth in February, March 17, 2016

Have a nice day, everybody!
Member Since: December 31, 1969 Posts: Comments:
273. Gearsts
7:17 AM GMT on March 17, 2016
Member Since: December 31, 1969 Posts: Comments:
272. vis0
7:17 AM GMT on March 17, 2016
Does a BrownOcean TS create upwelling over land?  If so, while making toast is that mud in   her/his  your  eye   face?
Member Since: December 31, 1969 Posts: Comments:
271. vis0
7:09 AM GMT on March 17, 2016
CREDIT:: NOAA, University of Washington (product shown is a custom filtered version of their products)    D&T:: 201603170300u_170630uAREA:: COnUS+s
NOTE1:: Interesting heading towards Grothar???
NOTE2:: There goes (unnoticed) Brown Ocean Bonnie @15n 58w (passing south of Nova Scotia) Bonnie??? If i remember i'll post the animation showing the closed micro LOW from Texas through North Carolina. Friend in Western Long Island thought it was weird how clouds circled to his south as is a TS.
Think someone mentioned it as it just North of North Carolina. If interested check this comment might add it HERE.
 
ImgLand.net image
Member Since: December 31, 1969 Posts: Comments:
270. HadesGodWyvern (Mod)
7:09 AM GMT on March 17, 2016
Mauritius Meteorological Services
Tropical Cyclone Advisory #8
Hurricane Warning
CYCLONE TROPICAL INTENSE EMERAUDE (06-20152016)
10:00 AM RET March 17 2016
===============================
Southeast of Diego Garcia

At 6:00 AM UTC, Intense Tropical Cyclone Emeraude (946 hPa) located at 10.6S 84.1E has 10 minute sustained winds of 110 knots with gusts of 155 knots. The cyclone is reported as moving southwest at 2 knots.

Hurricane Force Winds
===============
20 NM radius from the center, extending up to 25 NM in the northwestern quadrant

Storm Force Winds
============
25 NM radius from the center, extending up to 40 NM in the northwestern quadrant

Gale Force Winds
============
30 NM radius from the center, extending up to 60 NM in the northwestern quadrant

Near Gale Force Winds
=================
45 NM radius from the center, extending up to 50 NM in the southern semi-circle and up to 80 NM in the northwestern quadrant

Dvorak Intensity: T6.5/6.5/D1.5/6 HRS

Forecast and Intensity
===============
12 HRS: 10.6S 84.1E - 110 knots (Cyclone Tropical Intense)
24 HRS: 10.7S 84.8E - 110 knots (Cyclone Tropical Intense)
48 HRS: 11.4S 87.6E - 110 knots (Cyclone Tropical Intense)
72 HRS: 12.7S 89.1E - 100 knots (Cyclone Tropical Intense)

Additional Information
=================
The satellite and microwave presentation has clearly improved at the end of the night. The eye has warmed into a very cold central dense overcast in infrared channel. The last SSMIS data of 0142 UTC show the progressive building outside convective band around the central dense overcast, that may predict the beginning of a eyewall replacement cycle.

Emeraude seems to be quite stationary on the very last satellite imagery, and should turn gradually eastwards under the steering flow of a near equatorial ridge building in its northeast. During the weekend, the track should turn southwards then southwestwards as a subtropical ridge should gradually build south of the system. Global models are not in good agreement and differ sometimes strongly about the forward speed leading to significant spread in the guidance. The current forecast is close to the previous one and is a blend of the latest mean track from GFS-UKMO-EURO and GFS-EURO.

On this track, environmental conditions will remain mostly conducive during most of the forecast period. The system is located under an upper level ridge with a still improving upper level divergence polewards due to the remote effect of a transient upper level trough today and Friday. The environment could be a little less conducive later this weekend essentially due to an increase in northerly vertical wind shear. On the current forecast track, the system could pass over self-induced cool waters. Moreover, the internal dynamics, such as eyewall replacement cycle which is very likely with mature system but with poor forecast skill, could reduce the intensification rate. Given the small size of the system, rapid variation (including rapid intensification and rapid decay) are likely, bringing uncertainties in the forecast.
Member Since: December 31, 1969 Posts: Comments:

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Cat 6 lead authors: WU cofounder Dr. Jeff Masters (right), who flew w/NOAA Hurricane Hunters 1986-1990, & WU meteorologist Bob Henson, @bhensonweather