673 
FXUS64 KBMX 290649
AFDBMX

Area Forecast Discussion
National Weather Service Birmingham AL
149 AM CDT Thu Apr 29 2021

.UPDATE...
For 06Z Aviation.

&&

.SHORT TERM...
/Updated at 1245 PM CDT Wed Apr 28 2021/

As with previous days, little to no change was needed for the
short-term forecast. Observational trends with temperatures,
dewpoints, and general cloud presence has been good. I tweaked
temperatures a degree or two in places for anticipation of
lingering scattered clouds hampering this afternoon's highs.
Otherwise, looks like we're in pretty good shape through tomorrow
with a continuation of warm daytime weather and varying degrees of
cloud cover. I still expect low clouds and patchy fog across the 
south part of the area later tonight and early tomorrow morning.
These should mix out by mid morning.

40/Sizemore

Previous short-term discussion:
/Updated at 0349 AM CDT Wed Apr 28 2021/

Through Thursday.

Much of the Southeast is covered with high clouds as high pressure 
is off the Atlantic coast and will remain for the next several days. 
Southerly flow will continue to increase moisture over the area. 
This will help keep lows on the mild side and help increase 
afternoon temperatures each day. Look for mid to upper 80s each day 
through Thursday. Areas in the northwest may only reach the low 80s 
on Thursday due to added cloud cover with the approach of the front. 
Again will need to see if some fog can work into the southern 
counties overnight Wednesday night into Thursday. 

16

.LONG TERM...
/Updated at 0133 PM CDT Wed Apr 28 2021/

The models are finally coming into better agreement with regards 
to rain chances over the weekend and into early next week. The 
first wave of showers and a few storms due to arrive tomorrow
evening has been on a weakening trend the past few model runs as 
the upper level energy is being shifted closer to the cut-off low 
over the Southwest states. Rainfall amounts Thursday night and
Friday are likely to be less than one-quarter of an inch. The 
weekend is also looking mostly rain free as the forcing stays 
closer to the cut-off low. The cut-off low will eventually eject 
northeast and it looks like higher rain chances in order for 
Sunday night through Tuesday.

58/rose

Previous long-term discussion:
/Updated at 0349 AM CDT Wed Apr 28 2021/

Thursday night through Friday night.

A weak cold front moves into northwest Central AL Thursday night 
associated with a broad trough extending southwest from the Great 
Lakes Region into the ArkLaTex. Scattered to numerous showers will 
accompany the front as it arrives near the I-20 corridor at sunrise 
Friday morning. Initially, there will be a small chance for an 
occasional thunderstorm as well, but expect mostly rain after 
midnight. Coverage will wane during the morning limited by weak 
surface convergence and anticyclonic flow north of a mid-level ridge 
centered over the Gulf of Mexico. However, better defined lower-
level troughing beneath 500mb coupled with 1000-500mb mean RH of 80-
90% should provide enough synoptic lift and moisture to continue 
Likely PoPs before noon, although QPF amounts will be low. With 
daytime heating, could see better chances for scattered 
thunderstorms by the afternoon with most activity focused near the
I-85 corridor during that time. The front will settle across the 
Gulf of Mexico Friday night with only a small chance for a 
lingering shower in the far south. Lows will fall back into the
upper 40s north to upper 50s south.

Saturday through Tuesday.

High pressure will regain control on Saturday with partly cloudy 
skies and highs in the upper 70s to lower 80s. Models continue to 
resolve a cutoff low over Texas at the beginning of next week. 
However, the trends continue to exhibit large changes on a run to 
run basis. There is some agreement between the 00Z guidance that 
the cutoff low will eject towards the Lower MS Valley on Sunday 
and become a more progressive open wave downstream of a deepening 
trough over the Western CONUS. This would reinforce a warm 
advection regime across Central AL as the stalled front over the 
Gulf of Mexico begins to lift northwards on Sunday afternoon 
producing isentropic lift and scattered showers and thunderstorms.
Temperatures would warm into the 80s Sunday through Tuesday 
progressively warmer each day supported by strong height rises and
southwesterly flow around the western periphery of high pressure 
over the eastern Gulf of Mexico. With rising moisture, additional 
scattered showers and thunderstorms appear possible on Monday and 
Tuesday initiated by daytime heating and disturbances embedded 
within the southwesterly flow.

86


&&

.AVIATION...
06Z TAF Discussion.

Isentropic lift will become saturated overnight with the best 
chance for some IFR near sunrise will be near TOI/TCL/EET, with 
some chance at MGM. Otherwise, it appear like a rather short 
duration MVFR ceiling for the rest of the terminals. Clouds should
mix out and rise rather quickly and have VFR again by 1530z at 
all sites. Winds remain southerly on Thursday and slightly 
stronger around 11kts. Showers and storms will become possible
with a front that will move across the north between 0z and 6z. 

Note: AMD NOT SKED until further notice at KASN due to ongoing 
equipment issues.

16

&&

.FIRE WEATHER...

Rain free conditions are expected through Thursday afternoon. 
Southerly flow has brought humidity values upward the past 24 
hours and this trend will continue through Thursday. South winds 
3-5 mph tonight will become southwest 7-10 mph on Thursday. Rain 
chances will increase Thursday night and Friday morning as a weak 
cold front moves through the area. Rainfall amounts will be 
generally one-quarter of an inch or less Thursday night through 
Friday morning. Slightly cooler and drier air will overspread 
central Alabama Friday and Saturday.

&&

.PRELIMINARY POINT TEMPS/POPS...
Gadsden     85  58  77  49  78 /  10  60  20  10   0 
Anniston    86  61  77  51  79 /  10  60  20  10  10 
Birmingham  86  62  77  53  79 /  10  60  30  10  10 
Tuscaloosa  86  63  76  54  80 /  10  60  40  10  10 
Calera      84  63  76  54  78 /  10  60  40  10  10 
Auburn      83  64  78  56  78 /   0  40  40  10  10 
Montgomery  87  66  81  58  81 /  10  50  50  10  10 
Troy        86  67  82  59  81 /   0  50  50  10  10 

&&

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

&&

$$