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fxus64 kbmx 221136 

Area forecast discussion
National Weather Service Birmingham Alabama
636 am CDT Tue Oct 22 2019

for 12z aviation.


Short term...
/updated at 0315 am CDT Tue Oct 22 2019/

Today and tonight.

A cold front has moved through much of central Alabama overnight, but is
still lingering just south and east of the I-85 corridor first thing
this morning. These areas could see some light rain for a few more
hours before the front continues to move east of our area by mid-
morning. Behind the front, high pressure builds in, leading to clear
skies for much of the day. Tonight, the surface high moves across
central Alabama with the cooler air mass. This will help keep skies clear
overnight, which along with the calm winds, should allow for
effective radiational cooling. Morning lows are forecast to be in
the low to mid 40s.


Long term...
/updated at 0315 am CDT Tue Oct 22 2019/


As the mid-latitude cyclone currently over the upper Midwest lifts
up towards Hudson Bay, Aleutian troughing/eastern Pacific ridging
will help a mean trough remain over the central Continental U.S. As another
shortwave digs southward over the northern rockies. This will
maintain southwest flow aloft over central Alabama. A dry Post-
frontal air mass will result in rain-free conditions for Wednesday
and during the day on Thursday. Surface high pressure will slide
northeastward from the deep south Wednesday morning to the mid-
Atlantic on Thursday. Northerly to easterly component to winds at
the surface will keep the warming trend gradual with pleasant fall
conditions expected.

Late Thursday night through monday:

Models quickly diverge through the rest of the forecast period,
resulting in a low confidence forecast regarding pops and
temperatures. The European model (ecmwf) and Canadian continue to indicate a
closed, partially cutoff low developing over the southern High
Plains (trending westward vs. Previous runs), with a surface low
tracking from Texas to the Great Lakes over the weekend as a
kicker wave upstream causes the low to eject northeastward.
Meanwhile the GFS (and the NAM towards the end of its run)
indicate a much more progressive wave with an inverted trough at
the surface moving through on Friday. The GFS and European model (ecmwf)
deterministic runs generally agree with their ensembles, though
the European ensemble mean is wetter than the deterministic run
for Friday through Saturday. Stuck near wpc's preference leaning
towards the European ensemble mean, favoring a less progressive
solution but still higher pops very late Thursday night through
Friday, and chance pops thereafter.



12z taf discussion.

A pressure gradient will cause wind to remain gusty through the
afternoon. Skies should clear as dry air advects into the state
through the morning...with VFR conditions expected through the
rest of the taf period.



Fire weather...

A band of rain along a cold front will quickly exit the area this
morning. Cooler and drier conditions will follow for today through
Thursday. Minimum afternoon relative humidity values for Tuesday through Thursday
are expected to range from 30 to 35 percent. Moisture and rain
chances return for the end of the week.

The Alabama forestry commission continues to have a fire alert in
effect that includes all of central Alabama. For more information
about restrictions, visit their web site at forestry.Alabama.Gov.


Preliminary point temps/pops...
Gadsden 68 40 69 42 72 / 0 0 0 0 0
Anniston 70 42 70 44 73 / 0 0 0 0 0
Birmingham 69 45 70 46 73 / 0 0 0 0 0
Tuscaloosa 69 44 72 45 73 / 0 0 0 0 0
Calera 69 43 70 45 72 / 0 0 0 0 0
Auburn 71 45 69 46 72 / 10 0 0 0 0
Montgomery 73 45 72 46 75 / 0 0 0 0 0
Troy 72 45 71 46 74 / 10 0 0 0 0


Bmx watches/warnings/advisories/...

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