Moisture-Packed Atmosphere Fueling a Week of Severe Weather

By: Bob Henson , 7:29 PM GMT on July 14, 2015

While the North Atlantic has yet to produce a hurricane this year (see our post from Tuesday morning for a full tropical update), extremely muggy air across a broad swath of the Midwest has millions of people wiping their brows, downing untold gallons of iced beverages, and keeping an eye out for severe storms. The upper-level flow is often too weak by midsummer to support supercells, but a band of stronger jet-stream winds now extends from the Midwest toward the Northeast, lending support to evening thunderstorms congealing overnight into mesoscale convective systems (MCSs). One such MCS maintained itself across a jaw-dropping distance: it developed over Minnesota on Sunday night and was still recognizable as a weak line of storms pushing offshore from the Carolinas early Tuesday morning. Four tornadoes were reported late Sunday as the system organized over western Minnesota, and NOAA’s Storm Prediction Center (SPC) logged several hundred reports of high wind over the MCS track on Sunday night and Monday. Was this event a derecho (a long-lived, thuderstorm-related wind storm)? Although its winds were widespread, most reports were in the 60 – 70 mph range, which resulted in mainly minor damage. Derechoes typically have at least a few reports of winds gusting to at least 75 mph, as implied in SPC’s website on derechoes. However, the Sunday-Monday event as a whole is consistent with the characteristics of derechoes put forth in a widely cited 2005 BAMS paper. (Thanks to Stu Ostro, The Weather Channel, for background on derecho definitions.)


Figure 1. The progress of the mesoscale convective complex from Minnesota across the Midwest from late Sunday into Monday afternoon. Image credit: Greg Carbin/NOAA Storm Prediction Center.


Severe storms regenerated behind the initial MCS on Monday evening, bringing more heavy rain and high wind to parts of Illinois, Indiana, Kentucky, Ohio, and West Virginia that were struck the night before. Tennis-ball sized hail (2.5” diameter) was reported by a CoCoRaHS observer at Burnham-Wegewisch, IL (in Cook County, just southeast of Chicago), and hail close to 4” in diameter was observed near Marseilles, IL. Far west of the main action on Monday evening, a lone supercell in central Kansas produced a photogenic tornado northwest of Hutchinson (see Figure 2). By Monday evening, close to 200,000 customers had lost power as a result of the day’s storms, and flash flooding led to at least one fatality and some 150 homes damaged or destroyed in Johnson County, KY. All told, Monday produced a total of at least 477 “filtered” severe reports in the SPC database. That's the largest number on a single date since November 17, 2013, according to The Weather Channel’s Nick Wiltgen.

Yet another large MCS was making its way across southeastern Ohio on Tuesday afternoon. SPC has placed a region from eastern Kentucky and Tennessee through the Carolinas in an enhanced risk of severe weather for Tuesday afternoon and evening, with a large slight risk area covering much of the east-central U.S. and a smaller slight-risk area in western Kansas. Several dispersed areas of slight risk are in the SPC’s Day 2 outlook for Wednesday.


Figure 2. The only tornado reported with Monday’s severe weather occurred in central Kansas. Image credit: wunderphotographer rrose1. A YouTube video features a brief but spectacular clip of this tornado obtained via drone.


What’s making this summer so humid?
From the Midwest to the Southeast, the summer thus far has been marked by frequently sultry conditions. Dew point readings in the vicinity of 75°F have been commonplace; for a temperature of 95°F, this would correspond to a relative humidity of 53% and a heat index of 108°F. Nashville recorded a dew point of 81°F on Tuesday afternoon, its highest reading since August 1995. The moist conditions have been fostered by consistent southerly flow of near-surface air from the Gulf of Mexico, and at times by upper-level moisture streaming into the U.S. from the tropical Pacific, where El Niño continues to intensify. Some of the moisture has arrived from below, as summer heat allows water vapor to escape from wet soils left behind by record-setting rains. Both Texas and Oklahoma saw their wettest month on record in May, and Indiana, Illinois, and Ohio all saw their wettest June on record.


Figure 3. Temperature and dewpoint trace for Monday, July 13, from WU personal weather station KIAWATER4, located in Waterloo, IA. Dewpoints touched 80°F around midday.


The extremely unstable air across the Midwest this week is also a partial byproduct of agriculture. The highest U.S. dewpoints in July are often found not along the Gulf Coast but in the heart of the Corn Belt, as the enormous leaves of fast-growing corn plants send vast amounts of moisture into the air through evapotranspiration. As covered in depth by WU weather historian Chris Burt, the highest reliably measured dew point in the United States—an excruciating 90°F—was reported at Appleton, Wisconsin, on July 13, 1999 (with an air temperature of 101°F!). As farmers learn how to pack plants ever more tightly into limited space, there’s more leaf area per acre, which means more moisture pulled into the plant from deep roots can be sent back into the atmosphere. A team led by David Changnon (Northern Illinois University) published an analysis in 2003 of dewpoint increases observed at Chicago’s Midway Airport from 1928 through 2002. The authors attribute the rise to two factors: “(1) the existence of average to above-average regional precipitation anomalies occurring in May and during the [20-day] period prior to the heat event, and (2) changes in agricultural practices that have led to enhanced evapotranspiration rates in the Midwest.” A 2010 analysis by the Iowa Environmental Mesonet found that the average moisture content in the summertime atmosphere [Jun-Aug) at Des Moines increased by about 13% from 1974 to 2008, as cited in a report by Eugene Takle (Iowa State University).

We’ll have a new post by Wednesday afternoon at the latest.

Bob Henson


Figure 10. An eerie set of mammatus clouds developed over Otter Tail County, Minnesota, as a long-lived storm complex began taking shape on Sunday. Image credit: wunderphotographer spacey84.


Figure 10.. Monday’s fast-moving storm complex pushes through Indianapolis, IN, near Kuntz Stadium. Image credit: wunderphotographer mkennindy.




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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276. ncstorm
9:13 PM GMT on July 15, 2015
12z GFS


12z CMC


Member Since: December 31, 1969 Posts: Comments:
275. Jedkins01
7:42 PM GMT on July 15, 2015
Quoting 260. tampabaymatt:



I don’t understand why the HRRR model continues to show dry conditions for Tampa going into tomorrow morning. There is a strong line of storms progressing southward through the state that shows no signs of weakening. It’s already making its way into the Spring Hill area. Something weird going on with the models lately.



Model guidance has really been under expecting this event. Not sure why but the reason for what you're describing is because the models have had a north bias on the trough position and the energy. Model guidance had really high pops in the panhandle and even higher into Georgia with widespread heavy totals as of last night, but the trough position is further south today than the models show.

Now, I do still expect that line to weaken some because the trough axis of best lift and convergence is still to the north, but it wasn't even expected to reach Citrus and Levy counties, much less Hernando and Pasco. Model guidance does bring the trough further south into the weekend and brings much more rain coverage, but still I suspect considering it's already been more active than guidance, and with the troughing being already ahead of most models, I suspect that we'll see more than expected. Not a horrible flood event, just good rain and thunderstorm coverage with localized flooding possible in some spots where cells may train due to fast flow.

Member Since: December 31, 1969 Posts: Comments:
274. WunderAlertBot (Admin)
7:37 PM GMT on July 15, 2015
JeffMasters has created a new entry.
273. Jedkins01
7:35 PM GMT on July 15, 2015
Quoting 231. HurrMichaelOrl:



I agree with you Jedkins. I think the probability for instance, in the Orlando area, is much lower than areas near the west coast. Such high rainfall totals also seem to be more common up toward deltona, out toward Apopka and north of there. For my area, I would say the return period is at least 3-7 years for 4-7" rainfall totals. Interestingly, I seem to recall a 4" single day rainfall total here early this year (Jan-Mar). We probably actually get two 2-3" rainfall events from single day thunderstorm activity within the rainy season per year here. Like you said, I have also noticed closer to 2" is more typical than in the 3" range.

It looks like the storms are robust today and on the march toward the Orlando area. It is breezy and the air feels moist.



Yeah I agree, if you think about it, it makes sense because onshore flow events over a warm ocean are prone to generating major rain events, that can occur here in the west coast of FL both from tropical cyclones and from tropical waves, fronts, and other forms of low pressure. Also, typically when the sea breezes collide on either the east coast of west coast, the thunderstorm cells can persist longer than inland. For those reasons, I agree on the return period there vs. here, makes sense to me.
Member Since: December 31, 1969 Posts: Comments:
272. nonblanche
7:34 PM GMT on July 15, 2015
Quoting 241. wxgeek723:

Onshore flow + high tide + 2 inch per hour rainfall rates = very bad morning at the Jersey Shore












Seems to me I remember a weather system like that. Took like 3 tide cycles for it all to run off. Early 1970's? I remember wearing a 1 piece bathing suit and playing in the water in the street with my friends (Ventnor Heights, a block away from the back bay.) Fortunately the sand sharks stayed off the streets; we could have, I dunno, lost a toe or something.
Member Since: December 31, 1969 Posts: Comments:
271. BahaHurican
7:25 PM GMT on July 15, 2015
Quoting 267. 19N81W:

what happened to the convection that was supposed to happen in the western carib?....seems like there is a wall just to the west of Jamaica stopping every wave
Sure looked like you guys were going to get washed out yesterday! What happened to all that cloud cover between here and Honduras?
Member Since: December 31, 1969 Posts: Comments:
270. BahaHurican
7:23 PM GMT on July 15, 2015
Quoting 262. GeoffreyWPB:

... Significant weather advisory for frequent to excessive lightning
and 45 to 55 mph winds for east central Palm Beach County until 315
PM EDT...

* at 248 PM EDT... National Weather Service meteorologists detected a
strong thunderstorm over Greenacres... or near Lake Worth... moving
east at 15 mph.

* The primary impacts will be frequent to excessive lightning and
gusty winds of 45 to 55 mph. Lightning is the number one weather
related killer in Florida. Trees and open shelters offer no
protection. These winds can down small tree limbs and branches...
and blow around unsecured small objects. Seek shelter in a safe
building until the storm passes.

* Locations impacted include...
West Palm Beach... Wellington... Lake Worth... Riviera Beach... Palm
Beach... Greenacres... Royal Palm Beach... Palm Springs... Lantana...
Atlantis... Haverhill... Cloud Lake... gun Club Estates... Palm Beach
International Airport... lake Belvedere Estates... Golden Lakes...
Royal Palm estates... Port of Palm Beach... downtown West Palm Beach
and schall Circle.
This sounds like August ... just in time for back to school shopping for Bahamians. ... No wonder we love the mall in the afternoon ....
Member Since: December 31, 1969 Posts: Comments:
269. sanflee76
7:22 PM GMT on July 15, 2015
Just watching the radar and the storms just go poof as they come into the Sanford area. The storms were firing all day to the north and west and those are gone now. But then storms fire up south and east of here. Just can't seem to catch a break from all this dry hot weather. Going on day 8 now without a good rain. May need to turn on the lawn sprinklers
Member Since: December 31, 1969 Posts: Comments:
268. BahaHurican
7:20 PM GMT on July 15, 2015
Quoting 241. wxgeek723:

Onshore flow + high tide + 2 inch per hour rainfall rates = very bad morning at the Jersey Shore


Oh man ... the guy in the black car in the second photo must be freaked right out! .... That is one hell of a nice car to get that wet ....
Member Since: December 31, 1969 Posts: Comments:
267. 19N81W
7:16 PM GMT on July 15, 2015
what happened to the convection that was supposed to happen in the western carib?....seems like there is a wall just to the west of Jamaica stopping every wave
Member Since: December 31, 1969 Posts: Comments:
266. BahaHurican
7:14 PM GMT on July 15, 2015
Afternoon all.
Quoting 221. ncstorm:

12z operational GFS is picking on that disturbance that the Navgem ensembles were hinting at as well..

Weak though




Don't need it to be strong, just wet enough to dampen the ECar on its way through ... then it can fizzle out. NOT interested in any kinda storm up in here right now ...
Member Since: December 31, 1969 Posts: Comments:
265. BahaHurican
7:09 PM GMT on July 15, 2015
Wow.... a slow day in da blog....
Member Since: December 31, 1969 Posts: Comments:
264. sanflee76
7:06 PM GMT on July 15, 2015
Quoting 256. HurrMichaelOrl:

We shot the rain gap here, despite massive, heavy thunderstorms in all directions. Boy, do I feel like a broken record. Going to go out and water.

We also shot the rain gap too Michael. Happens all the time here lately. Haven't had a good rain in 8 days and counting now.
Member Since: December 31, 1969 Posts: Comments:
263. tiggerhurricanes2001
7:06 PM GMT on July 15, 2015
Interesting from TWC on Claudette:

ATLANTIC
The remnant low-level circulation of the borderline-but-officially-tropical storm (Claudette) is now near the southeast Canadian Maritimes with just some showers and with an area of clouds not very distinguishable on satellite imagery from a bunch of others.

While the tropics per se in the Atlantic remain quite devoid of thunderstorms, at a higher latitude the atmosphere & NHC snuck in another one, with now there already having been the C storm. This is only the third time in the past decade (2006-2015) that has occurred so early.

For a seasonal forecast to verify which predicted only seven tropical/subtropical storms, there'd need to be only four more through the entire remainder of the season.

Member Since: December 31, 1969 Posts: Comments:
262. GeoffreyWPB
7:05 PM GMT on July 15, 2015
... Significant weather advisory for frequent to excessive lightning
and 45 to 55 mph winds for east central Palm Beach County until 315
PM EDT...

* at 248 PM EDT... National Weather Service meteorologists detected a
strong thunderstorm over Greenacres... or near Lake Worth... moving
east at 15 mph.

* The primary impacts will be frequent to excessive lightning and
gusty winds of 45 to 55 mph. Lightning is the number one weather
related killer in Florida. Trees and open shelters offer no
protection. These winds can down small tree limbs and branches...
and blow around unsecured small objects. Seek shelter in a safe
building until the storm passes.

* Locations impacted include...
West Palm Beach... Wellington... Lake Worth... Riviera Beach... Palm
Beach... Greenacres... Royal Palm Beach... Palm Springs... Lantana...
Atlantis... Haverhill... Cloud Lake... gun Club Estates... Palm Beach
International Airport... lake Belvedere Estates... Golden Lakes...
Royal Palm estates... Port of Palm Beach... downtown West Palm Beach
and schall Circle.
Member Since: December 31, 1969 Posts: Comments:
261. Grothar
6:43 PM GMT on July 15, 2015
Member Since: December 31, 1969 Posts: Comments:
260. tampabaymatt
6:43 PM GMT on July 15, 2015
Quoting 256. HurrMichaelOrl:

We shot the rain gap here, despite massive, heavy thunderstorms in all directions. Boy, do I feel like a broken record. Going to go out and water.


I don’t understand why the HRRR model continues to show dry conditions for Tampa going into tomorrow morning. There is a strong line of storms progressing southward through the state that shows no signs of weakening. It’s already making its way into the Spring Hill area. Something weird going on with the models lately.
Member Since: December 31, 1969 Posts: Comments:
259. ncstorm
6:42 PM GMT on July 15, 2015
12z CMC on the potential Central Atlantic disturbance

Member Since: December 31, 1969 Posts: Comments:
258. HurrMichaelOrl
6:41 PM GMT on July 15, 2015
Quoting 255. rmbjoe1954:



C'mon Scott. Bring some rain down to me - east of US1. I am meeting my college kid in Orlando tomorrow and going to Hollywood Studios in the morning. Please hold up on the rain until the afternoon.


Rain? What rain?
Member Since: December 31, 1969 Posts: Comments:
257. ncstorm
6:39 PM GMT on July 15, 2015

12z
Member Since: December 31, 1969 Posts: Comments:
256. HurrMichaelOrl
6:38 PM GMT on July 15, 2015
We shot the rain gap here, despite massive, heavy thunderstorms in all directions. Boy, do I feel like a broken record. Going to go out and water.
Member Since: December 31, 1969 Posts: Comments:
255. rmbjoe1954
6:36 PM GMT on July 15, 2015
Quoting 254. StormTrackerScott:



No rain at the office. A little at my house though. Seem to be in a gap across the northside of Orlando


C'mon Scott. Bring some rain down to me - east of US1. I am meeting my college kid in Orlando tomorrow and going to Hollywood Studios in the morning. Please hold up on the rain until the afternoon.
Member Since: December 31, 1969 Posts: Comments:
254. StormTrackerScott
6:28 PM GMT on July 15, 2015
Quoting 250. HurrMichaelOrl:

Winds probably gusting to 35mph here in Winter Park and steady 20-25. I hope we don't shoot the gap between these initial storms, as they will be the strongest we likely get (or don't) today.


No rain at the office. A little at my house though. Seem to be in a gap across the northside of Orlando
Member Since: December 31, 1969 Posts: Comments:
253. barbamz
6:25 PM GMT on July 15, 2015
Iraq declares Thursday an official holiday due to heat wave
Associated Press, 3 hours ago
BAGHDAD (AP) — Iraq's government has announced that Thursday will be an official holiday due to a scorching heatwave.
In a brief statement Wednesday, the Iraqi Cabinet said temperatures already have exceeded 50 degrees Celsius (122 Fahrenheit) in some provinces.
Meteorological officials warned of a heat wave in central and southern Iraq starting Wednesday through Friday. The heat wave comes as Muslims are practicing dawn-to-dusk fasting during the holy month of Ramadan.
Such heatwaves in Iraq add to the population's hardships as the country suffers from a lack of electricity. To cope with high temperatures, Iraqis either stay indoors or swim in rivers. In some public places, showers are set up for those who want to cool down.
Member Since: December 31, 1969 Posts: Comments:
250. HurrMichaelOrl
6:21 PM GMT on July 15, 2015
Winds probably gusting to 35mph here in Winter Park and steady 20-25. I hope we don't shoot the gap between these initial storms, as they will be the strongest we likely get (or don't) today.
Member Since: December 31, 1969 Posts: Comments:
248. Grothar
6:20 PM GMT on July 15, 2015
Member Since: December 31, 1969 Posts: Comments:
246. StormTrackerScott
6:12 PM GMT on July 15, 2015
Quoting 244. ricderr:

WOW! And you wonder why the models forecasting the Strongest El-Nino EVER! We are already seeing a rapidly developing Kelvin Wave as deep as nearly 150m. Values went from negative to positive 3C in just 2 weeks and still growing very fast. This kelvin Wave is getting going as a result of record Westerly wind anomalies and a record breaking MJO

did you know the kelvin wave in 2009 was deeper


Doesn't matter there are rapid increases happening as a result of this WWB @ around 150m and it will be interesting to see how high these anomalies go the next several weeks. No question at all that we are on our way to 1982/1997 levels.
Member Since: December 31, 1969 Posts: Comments:
245. 882MB
6:10 PM GMT on July 15, 2015
Quoting 221. ncstorm:

12z operational GFS is picking on that disturbance that the Navgem ensembles were hinting at as well..

Weak though






I believe is the tropical wave, SW of the Cape Verde Islands, that the 2 models are referring too.


Member Since: December 31, 1969 Posts: Comments:
244. ricderr
6:06 PM GMT on July 15, 2015
WOW! And you wonder why the models forecasting the Strongest El-Nino EVER! We are already seeing a rapidly developing Kelvin Wave as deep as nearly 150m. Values went from negative to positive 3C in just 2 weeks and still growing very fast. This kelvin Wave is getting going as a result of record Westerly wind anomalies and a record breaking MJO

did you know the kelvin wave in 2009 was deeper
Member Since: December 31, 1969 Posts: Comments:
243. StormTrackerScott
5:57 PM GMT on July 15, 2015
WOW! And you wonder why the models forecasting the Strongest El-Nino EVER! We are already seeing a rapidly developing Kelvin Wave as deep as nearly 150m. Values went from negative to positive 3C in just 2 weeks and still growing very fast. This kelvin Wave is getting going as a result of record Westerly wind anomalies and a record breaking MJO

Philip Klotzbach %u200F@philklotzbach 26m26 minutes ago
Since June 1, westerly winds have been stronger in the Central Pacific than any year on record (since 1979). #ElNino


Just a remarkable increase in a matter of days. This will likely we one of the strongest Kelvin Waves we've ever seen in about a 6 to 8 weeks.

Member Since: December 31, 1969 Posts: Comments:
242. barbamz
5:53 PM GMT on July 15, 2015
Mayors of major cities, California governor to attend Vatican conference on climate change
Catholic World News - July 15, 2015
Bishop Marcelo Sánchez Sorondo, the chancellor of the Pontifical Academy of Sciences and the Pontifical Academy of Social Sciences, took part in a July 15 press conference on an upcoming Vatican workshop on “Modern Slavery and Climate Change: the Commitment of the Cities” (July 21) and symposium on “Prosperity, People, and Planet: Achieving Sustainable Development in Our Cities.” ...
The list of participants includes over 50 mayors from some of the world’s major cities, including Rome, Florence, Milan, Tehran, Sao Paolo, Mexico City, Johannesburg, Paris, and Madrid, as well as a handful of other officials such as Governor Jerry Brown of California.
Mayors from the United States who will attend include the majors of Birmingham, Boston, Boulder, Minneapolis, New Orleans, Portland, San Francisco, San Jose, and Seattle.
Member Since: December 31, 1969 Posts: Comments:
241. wxgeek723
5:53 PM GMT on July 15, 2015
Onshore flow + high tide + 2 inch per hour rainfall rates = very bad morning at the Jersey Shore









Member Since: December 31, 1969 Posts: Comments:
239. BayFog
5:51 PM GMT on July 15, 2015
As I discovered several weeks ago, those SST overlays are not being updated currently. Disregard them.
Quoting 232. ILwthrfan:

Must be one cold atmosphere above Nangka.  She's sitting over 20-21C SST and maintaining.  Impressive.

Also seems to be a bit better organized vs. 12 to 6 hours ago.




Well now I'm a bit confused.

Levis site has SST around 26-27?



But NOAAs SST layer within satellite loops has it this area between 20-22C with a rather sharp gradient?

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238. tampabaymatt
5:41 PM GMT on July 15, 2015
Member Since: December 31, 1969 Posts: Comments:
237. weathermanwannabe
5:30 PM GMT on July 15, 2015
Quoting 236. HurrMichaelOrl:


Does that show 108F for Tallahassee? Geez.

Hottest May, June, July so far that I have experienced in Tallahassee since I have lived here (2001) and just spoke to an old timer here since 1962; hottest summer so far he has seen up here/can remember.
Member Since: December 31, 1969 Posts: Comments:
236. HurrMichaelOrl
5:27 PM GMT on July 15, 2015
Quoting 227. hurricanes2018:

summer weather!

Does that show 108F for Tallahassee? Geez.
Member Since: December 31, 1969 Posts: Comments:
235. LargoFl
5:26 PM GMT on July 15, 2015
Member Since: December 31, 1969 Posts: Comments:
234. weathermanwannabe
5:26 PM GMT on July 15, 2015
Based on this shot from about 2 hours ago, looks to me like the curvature of the approaching coast of Japan might be helping out the circulation pattern; getting a nice burst of convection at the core (per the post below) which is trying to wrap around:

Member Since: December 31, 1969 Posts: Comments:
233. washingtonian115
5:23 PM GMT on July 15, 2015
Quoting 230. hurricanes2018:



wow!!
The euro was showing a decent wave.Don't know if it dropped it.
Member Since: December 31, 1969 Posts: Comments:
232. ILwthrfan
5:18 PM GMT on July 15, 2015
Must be one cold atmosphere above Nangka.  She's sitting over 20-21C SST and maintaining.  Impressive.

Also seems to be a bit better organized vs. 12 to 6 hours ago.




Well now I'm a bit confused.

Levis site has SST around 26-27?



But NOAAs SST layer within satellite loops has it this area between 20-22C with a rather sharp gradient?
Member Since: December 31, 1969 Posts: Comments:
231. HurrMichaelOrl
5:12 PM GMT on July 15, 2015
Quoting 223. Jedkins01:


I've had a rain gauge at my location for 10 years, we've had several 4-7 inch days in the last 10 years, and although we went 3 years without one, there was one year where we had 3 in one year.

The chance of seeing 4-7 inches in one day increases significantly towards the gulf coast especially from south Louisiana all the way east along the coast and down into SW Florida, this also applies for east and southeast Florida. The farther north and inland you go, the probability decreases. Given this, we live in a high probability zone for an average return period for a 4-7 inch day event, and it's more common than every 10 years.

But, I agree, let's be really liberal and say it happens once a year for a given location around here, even if that's true, to see it multiple times is unlikely.

But 2-3 inch thunderstorm days are relatively common here, I see several of them at my rain gauge every summer on average, although it seems a lot easier to get 2 inches here than 3 from one thunderstorm event, and that makes sense given that a thunderstorm cell will often either weaken or move on elsewhere.


I agree with you Jedkins. I think the probability for instance, in the Orlando area, is much lower than areas near the west coast. Such high rainfall totals also seem to be more common up toward deltona, out toward Apopka and north of there. For my area, I would say the return period is at least 3-7 years for 4-7" rainfall totals. Interestingly, I seem to recall a 4" single day rainfall total here early this year (Jan-Mar). We probably actually get two 2-3" rainfall events from single day thunderstorm activity within the rainy season per year here. Like you said, I have also noticed closer to 2" is more typical than in the 3" range.

It looks like the storms are robust today and on the march toward the Orlando area. It is breezy and the air feels moist.
Member Since: December 31, 1969 Posts: Comments:
230. hurricanes2018
5:08 PM GMT on July 15, 2015


wow!!
Member Since: December 31, 1969 Posts: Comments:
229. hurricanes2018
5:07 PM GMT on July 15, 2015
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228. Climate175
5:03 PM GMT on July 15, 2015
Quoting 224. washingtonian115:

That storm will switch between Texas to Maine before a finale solution.
As the model routine always does before the real deal.
Member Since: December 31, 1969 Posts: Comments:
227. hurricanes2018
5:00 PM GMT on July 15, 2015
Quoting 201. Climate175:


summer weather!
Member Since: December 31, 1969 Posts: Comments:
226. hurricanes2018
5:00 PM GMT on July 15, 2015
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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