National Weather Service Raw Text Product

946 
FXUS64 KBMX 291215
AFDBMX

Area Forecast Discussion
National Weather Service Birmingham AL
615 AM CST Sun Nov 29 2020

.UPDATE...
For 12Z Aviation.

&&

.SHORT TERM...
/Updated at 406 AM CST Sun Nov 29 2020/
Today through Monday.

The satellite is currently indicating considerable high cloudiness 
across Central Alabama this AM. Our next weather maker, a surface 
low pressure system, is still out over the TX coast. It is 
expected to move to the ENE along the NW Gulf Coast and into S AL 
now into this evening. It is then expected to race NE up the 
Atlantic States as another front catches up with it. In the upper 
levels, a closed upper low over the TX/OK Panhandle will open up 
and swing eastward across TX/OK/AR/LA today. Ahead of it, 
extensive high moisture will continue to be ejected out across the
Deep South. This evening, this upper low is expected to be 
absorbed into the main upper trough digging ESE across C Conus 
tonight and then across E Conus on Monday. Showers and a few 
thunderstorms are expected to spread across C AL today as the 
system gets closer and moisture increases . Currently, the 
atmosphere has a bit of work to do to recover with dew points 
anywhere from 39 at Haleyville to 54 at Troy as of 10z. While some
gusty winds are possible, instability is meager. However, all 
should get some beneficial rain through tonight. The system will 
quickly pull to the NE on Monday. However, with the upper system 
still going across E Conus, a few very light showers are possible 
across the NE counties. As the upper low is moving across Monday, 
colder air will be invading as well. During the late afternoon 
hours, some flurries may be mixed in with the rain sprinkles 
before all of the moisture is tapped out. No accumulations or 
impacts are expected as moisture will be very shallow.

08

.LONG TERM...
/Updated at 406 AM CST Sun Nov 29 2020/
Monday night through Saturday.

A strong vorticity maximum will be located over the forecast area 
Monday evening as deep trough becomes an closed low over the
eastern United States. There may be enough lingering moisture 
and steep lapse rates for flurries across our northeastern 
counties during the evening. Strong cold advection will continue 
overnight with lows on Tuesday morning ranging from the lower 20s 
northwest to the upper 20s southeast. Temperatures will only rise 
into the 40s during the afternoon for most of our forecast area as
cold northwest flow continues. 

Temperatures will moderate for Wednesday and Thursday as heights 
rise in advance of a developing trough over the Southern Plains. 
deep-layer westerly flow develops. The upper-level trough is 
expected to be rather slow-moving, with sufficient time for 
southerly flow to transport moisture northward. Rain may begin 
affecting our western areas Thursday afternoon into Thursday night 
and slowly move eastward on Friday. Exact timing is unclear which
is currently a limiting factor for POPs for any given 12 hour 
period. The upper-level trough is expected to move east of the 
area on Saturday with cooler and dry conditions to follow. 

87/Grantham

&&

.AVIATION...
12Z TAF Discussion.

Conditions will deteriorate as we progress during the day as a low
pressure system over the NW Gulf moves toward AL today. Ahead of
the system, some IFR/MVFR cigs will make some meager progress 
from GA into TOI/ANB respectively. At the same time, MVFR 
conditions will move in from SW with the SHRA activity (& some TS)
later this morning. Conditions should go to IFR for many during 
the late afternoon and all by evening. Winds will be gusty as the 
front moves through tonight. 

08

&&

.FIRE WEATHER...

Rain will become widespread by this afternoon and evening as a 
strong storm system moves through. Much colder and drier conditions 
will arrive for Monday and Tuesday with northwesterly flow. RH 
values will remain quite high through Monday. Much lower RH values 
are expected for Tuesday.

&&

.PRELIMINARY POINT TEMPS/POPS...
Gadsden     61  37  45  25  45 / 100 100  10  10   0 
Anniston    63  42  46  26  46 / 100 100  10  10   0 
Birmingham  61  40  45  27  47 / 100 100  10  10   0 
Tuscaloosa  60  40  46  26  50 / 100  90   0   0   0 
Calera      61  41  46  28  47 / 100 100  10  10   0 
Auburn      61  45  48  28  46 / 100 100  10  10   0 
Montgomery  64  45  51  28  50 / 100 100   0   0   0 
Troy        66  45  51  28  50 / 100 100   0   0   0 

&&

.BMX WATCHES/WARNINGS/ADVISORIES/...
None. 

&&

$$

08/87