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fxus64 kbmx 171157 

Area forecast discussion
National Weather Service Birmingham Alabama
557 am CST Fri Jan 17 2020

for 12z aviation.


Short term...
/updated at 0358 am CST Fri Jan 17 2020/

Through tonight.

Light returns on radar this morning, however the overall airmass is
too dry for those echoes to reach the surface. A sprinkle of two can
not be ruled out but as for measurable rainfall today, none is
expected. Highs will be in the 50s to low 60s, due to cloud cover
through the day.

As we work into the evening hours, the next cold front will begin to
work toward the area. While the front is expected to remain west of
the area until Saturday, we could begin to see rainfall associated
with a pre-frontal trough across the west. Still only expecting
isolated to scattered showers after midnight at best, but chances
will be increasing rapidly into the day Saturday. Lows will be in
the 40s across the east and upper 40s to low 50s in the west.


Long term...
/updated at 0358 am CST Fri Jan 17 2020/

Saturday through Friday.

A cold front will push southeastward through central Alabama on Saturday.
The parent surface low begins to occlude over the Great Lakes, which
will help weaken the overall frontogenic forcing. Upper level flow
around this time also becomes more zonal, further limiting the
uplift. Therefore, while rain showers are expected to be fairly
widespread, we should see a gradual decrease in coverage as the
front moves southeastward through our area. I don't expect there to
be much instability to work with in the environment ahead of this
system, so the thunderstorm potential is limited.

The cold front is south and east of central Alabama by Sunday morning,
ending any rain chances. Surface high pressure associated with the
colder and drier air mass builds in Sunday through Tuesday. This
will keep the area rain-free and much colder than the previous few
weeks. Low temperatures will be in the 20s with highs in the 40s. We
warm slightly on Wednesday and Thursday as the upper level ridging
builds overhead and the surface high shifts to the New England
coast, which will allow for a somewhat warmer southerly flow.

Another trough dips through The Rockies and develops a surface low
in the Central Plains Thursday. This will likely bring our next
chance of rain late Thursday into Friday as the system moves
eastward. However, while model guidance seems to be in relative
agreement on the timing of the system, the evolution of the trough
and track of the surface low remains in question. Therefore, i've
capped pops around 50% on Friday and haven't mentioned any
thunderstorms due to the current lack of instability in model



12z taf discussion.

Mainly a wind forecast for the next 12 hours. Look for easterly
winds this morning, and then southeast by the afternoon. Speeds
will increase during the afternoon to 10-13kts. Cigs begin to
lower at the end of the forecast period with the approach of the
next rain system. Could be a window of low level wind shear for the northern sites
overnight tonight as the system approaches, so added in here.



Fire weather...

Mostly dry weather today, though some scattered light rain can't
be ruled out. Widespread showers will return to central Alabama
late tonight and Saturday as another cold front moves through the


Preliminary point temps/pops...
Gadsden 57 42 57 33 46 / 10 20 90 30 0
Anniston 58 43 59 35 48 / 10 20 90 50 0
Birmingham 58 48 60 36 48 / 10 20 90 30 0
Tuscaloosa 61 49 64 36 50 / 10 30 90 20 0
Calera 59 46 61 36 48 / 10 20 90 30 0
Auburn 57 45 60 41 50 / 0 10 70 60 0
Montgomery 62 49 65 42 52 / 10 10 90 60 0
Troy 62 50 66 45 53 / 10 10 80 60 0


Bmx watches/warnings/advisories/...

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