Special Weather Statement, NWS Birmingham, AL

Area Forecast Discussion
National Weather Service Birmingham AL
650 AM CDT Mon May 3 2021

.UPDATE...
For 12Z Aviation.

&&

.SHORT TERM...
/Updated at 0100 AM CDT Mon May 03 2021/

A warm front is now north of much of Central Alabama, stretching
from Huntsville to Auburn. A few clusters of storms over northern
MS are moving to the north northeast and will not impact the local
area. Showers are developing across southern MS and those will be
the next wave of activity to watch. Cannot rule out this activity
producing damaging winds or a brief tornado overnight.

Surface instability will increase, especially by this afternoon,
as dewpoints rise in to the upper 60s to lower 70s, with CAPE values
near or above 2000 J/kg. 30-40kts of shear will sustain updrafts,
with good lapse rates as mid to upper level temperatures cool.
Main threats today will be damaging winds and large hail, with the
best chance of severe storms south of I-20.

Looking toward Tuesday, instability parameters remain high as the
next, and stronger, shortwave and surface cold front approach the
area from the west. Some uncertainty exists regarding convective
mode and will need to rely on mesoscale processes as convection
develops upstream Tuesday morning and early afternoon.

14

.LONG TERM...
/Updated at 0100 AM CDT Mon May 03 2021/

Wednesday through Sunday.

The main trough axis continues to move east of our area early
Wednesday morning. The frontal boundary takes its time getting out
of the area, however, so expect lingering showers across the
southeast through the day, though any thunderstorm chance will be
dwindling as we transition to more of a zonal flow aloft and see
slight amplification of the 850mb ridge int he wake of the trough.

The zonal flow becomes more of a northwesterly flow aloft Thursday
into Friday as another impulse digs out a trough across the Eastern
CONUS. Model guidance still varies somewhat on if this trough will
reach far enough south to bring any chance of rain Thursday night.
For now, will stick closer to the Euro solution, which has better
ensemble agreement, keeping the area dry through Saturday with low
level ridging building across the Gulf States.

A weak upper level shortwave trough slides across the Central Plains
and develops a surface low Saturday night. This low is expected
to slide quickly eastward across the Ohio Valley Sunday morning
through the afternoon, draping a frontal boundary through the MS
Valley. Model guidance varies on the strength of the ridge and
just how far south the frontal boundary reaches by Sunday, so I've
kept rain/thunderstorm chances around 30-40% for Sunday afternoon
across the northern half of Central AL for now. This forecast
will likely change in coming days as we hopefully start to see
more model agreement.

25/Owen

&&

.AVIATION...
12Z TAF Discussion.

An active weather period thru at least 02z. Numerous showers and
a few tstms have been ongoing this early this morning along and
east of I-65. Widespread MVFR cigs with lcl IFR cigs will
gradually improve thru the day with cigs above 3k feet agl by 18z.
After 18z and outside convective areas, cigs should stay above 3k
feet thru 08z, and then lower to arnd 1500-2000 ft agl by 09z. A
few tstms may be severe from 16z thru 01z with large hail and wind
gusts up to 55 knots. Convective activity should decrease rapidly
after sunset, with only isolated showers/tstms after 02z.

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

58/rose

&&

.FIRE WEATHER...

Another round of scattered to numerous showers and storms are
expected today, and again on Tuesday before a cold front moves
through the day. Winds will increase from the south and become
southwesterly today. Speeds of 10-12mph are possible today. Drier
air arrives for Thursday and Friday.

&&

.PRELIMINARY POINT TEMPS/POPS...
Gadsden     81  68  82  60  77 /  60  20 100  90  40
Anniston    80  69  82  63  77 /  70  30 100  90  50
Birmingham  82  71  82  62  77 /  60  20 100  90  40
Tuscaloosa  84  71  83  62  78 /  50  20 100  80  30
Calera      81  71  81  64  77 /  60  20 100  90  40
Auburn      78  70  81  66  78 /  60  30  90  80  70
Montgomery  82  73  85  68  80 /  60  30  80  80  60
Troy        81  72  85  68  80 /  60  30  70  70  80

&&

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

&&

Hazardous Weather Outlook
National Weather Service Birmingham AL
354 AM CDT Mon May 3 2021

ALZ011>015-017>050-041200-
Marion-Lamar-Fayette-Winston-Walker-Blount-Etowah-Calhoun-Cherokee-
Cleburne-Pickens-Tuscaloosa-Jefferson-Shelby-St. Clair-Talladega-
Clay-Randolph-Sumter-Greene-Hale-Perry-Bibb-Chilton-Coosa-Tallapoosa-
Chambers-Marengo-Dallas-Autauga-Lowndes-Elmore-Montgomery-Macon-
Bullock-Lee-Russell-Pike-Barbour-
354 AM CDT Mon May 3 2021

This Hazardous Weather Outlook is for the counties served by the
National Weather Service office in Birmingham.

.DAY ONE...Outlook through Tonight.

Strong to severe thunderstorms possible today and into the evening
hours. Higher chance of severe storms along and south of I-20.
Threats include damaging winds up to 60 mph and large hail.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

Strong to severe thunderstorms are possible Tuesday and Tuesday
evening across the all of Central Alabama. Threats include damaging
winds up to 70 mph, large hail and isolated tornadoes.

.SPOTTER INFORMATION STATEMENT...

Activation of storm spotters and emergency management may be
needed today and again Tuesday.

Special Weather Statement
National Weather Service Birmingham AL
539 AM CDT Mon May 3 2021

ALZ021-027-028-031115-
Clay AL-Talladega AL-Cleburne AL-
539 AM CDT Mon May 3 2021

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN TALLADEGA...
SOUTHWESTERN CLEBURNE AND NORTHERN CLAY COUNTIES UNTIL 615 AM CDT...

At 539 AM CDT, Doppler radar was tracking a strong thunderstorm near
Waldo, or 7 miles south of Talladega, moving northeast at 55 mph.

Winds in excess of 40 mph will be possible with this storm.

Locations impacted include...
Oxford, Talladega, Munford, Waldo, Anniston Regional Airport, Delta,
Mount Cheaha, Camp Mac, Chandler Springs, Ironaton, Lake Chinnabee
and Gunthertown.

LAT...LON 3340 8565 3323 8613 3336 8622 3359 8586
      3359 8580 3356 8580 3355 8576
TIME...MOT...LOC 1039Z 240DEG 50KT 3332 8609

25/Owen

Special Weather Statement
National Weather Service Birmingham AL
741 AM CDT Mon May 3 2021

ALZ021-029-031300-
Randolph AL-Cleburne AL-
741 AM CDT Mon May 3 2021

...SIGNIFICANT WEATHER ADVISORY FOR NORTHERN RANDOLPH AND
SOUTHEASTERN CLEBURNE COUNTIES UNTIL 800 AM CDT...

At 741 AM CDT, Doppler radar was tracking a strong thunderstorm near
Morrison Cross Roads, or 11 miles north of Wedowee, moving east at 35
mph.

Winds in excess of 40 mph will be possible with this storm.

Locations impacted include...
Ranburne, Morrison Cross Roads, Fosters Cross Roads, Trickem, Graham,
Newell and Micaville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
office in Birmingham.

&&

LAT...LON 3341 8556 3350 8558 3362 8533 3343 8530
TIME...MOT...LOC 1241Z 249DEG 32KT 3347 8551

40/Sizemore