Special Weather Statement, NWS Birmingham, AL

Area Forecast Discussion
National Weather Service Birmingham AL
728 PM CDT Sat Aug 18 2018

.UPDATE...
For 00Z Aviation.

&&

.SHORT TERM...
Through Tonight.

Majority of the showers and and thunderstorms have been confined
to the southern portions of Central Alabama this afternoon. Low
level convergence was likely higher across this area as low level
winds had a more southerly component than across the north. Models
show deep moisture remaining across most of the area overnight, with
drier mid level air advecting across areas north of the I-22/I-20
corridor. Expect scattered showers and a few thunderstorms overnight,
with better rain chances south of I-20.

58/rose

.LONG TERM...
Sunday through Friday.

A pattern of broad low-level confluence will combine with very
moist deep-layer west-southwest flow on Sunday as an upper-level
trough moves eastward off the coast of the Carolinas. This setup
should be favorable for numerous showers and storms with rain
chances in the 60-70 percent range.

Models are in good agreement on Monday into Tuesday and indicate a
well-organized system ejecting from the Central Plains toward the
Great Lakes. Low-level convergence and moisture advection is
expected over a wide area from the Gulf Coast to the Ohio Valley,
and this should lead to high rain chances across Alabama. Where
stronger upper-level support exists, some risk of organized severe
storms may be found to our north and west on Monday. This threat
could shift toward our area on Tuesday but would require more
deep-layer shear than currently indicated by the global models.

A cold front may pass through our northern areas on Tuesday night
into Wednesday and then begin to lose forward momentum across the
middle of the forecast area. However, the front may get shoved
southward by a secondary shortwave rotating around the base of the
large-scale trough on Wednesday night. This would lead to a dry
period on Thursday and Friday with much lower humidity and cooler
mornings as high pressure moves in from the north.

87/Grantham

&&

.AVIATION...
00Z TAF Discussion.

Convection has dissipated rather quickly early this evening, and
have mention of some light rain only at TOI. It appears thats
whats left of the rain will not impact any other terminals. There
will be some scattered showers/storms around but chances will become
too low to mention until Sunday. Some low clouds are floating
around in Central Alabama early this evening and added a mention
of brief MVFR ceilings the next few hours.

Overall conditions are not too different from last night. A west
southwest flow along pressure and isentropic surfaces will allow
cooling to near saturation overnight. Mentioned the same general
idea as last night and the trend advertised in the previous
forecast. MVFR/IFR ceilings developing around 06z and then
becoming IFR until daybreak. Fog does not appear to be a huge
issue as some wind will be blowing, although light. Added some
minor restrictions in fog here and there and will monitor
especially the areas that received rain this afternoon.

Ceilings jump to MVFR after sunrise and will probably be erratic
in lifting through the morning. Started off the mention of
convection with PROB30 thunder beyond 18z. Will most likely have
to increase this rain mention at some terminals as we approach
late Sunday morning and afternoon.

Surface winds generally becoming light south southwest overnight
and increase to southwest around 8kts by afternoon.

75

&&

.FIRE WEATHER...

Rain chances remain high through the weekend as a cold front
slowly approaches the forecast area and the airmass remains
unseasonably wet. Low stratus and patchy fog will lift slowly this
morning, and expect similar conditions tonight/Sunday morning.
There are no fire weather concerns at this time.

&&

.PRELIMINARY POINT TEMPS/POPS...
Gadsden     70  85  71  87  72 /  40  70  40  70  40
Anniston    70  86  71  87  72 /  40  70  40  70  40
Birmingham  72  87  73  88  73 /  30  70  40  70  40
Tuscaloosa  73  88  73  89  74 /  30  70  40  70  40
Calera      70  86  72  86  72 /  40  70  40  70  40
Auburn      71  84  72  86  72 /  40  70  30  60  30
Montgomery  72  89  73  88  73 /  40  70  30  60  30
Troy        72  87  72  88  72 /  40  70  30  60  20

&&

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

&&

Hazardous Weather Outlook
National Weather Service Birmingham AL
502 AM CDT Sat Aug 18 2018

ALZ011>015-017>050-191315-
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-
502 AM CDT Sat Aug 18 2018

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

.DAY ONE...Outlook through Tonight.

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Activation of storm spotters and emergency management is not
expected at this time.

Special Weather Statement
National Weather Service Birmingham AL
745 PM CDT SAT AUG 18 2018

ALZ019-020-190115-
Calhoun AL-Cherokee AL-
745 PM CDT SAT AUG 18 2018

...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN CALHOUN AND SOUTH
CENTRAL CHEROKEE COUNTIES UNTIL 815 PM CDT...

At 745 PM CDT, Doppler radar was tracking a strong thunderstorm near
Piedmont, moving northeast at 10 mph.

Pea size hail and winds in excess of 40 mph will be possible with
this storm.

Locations impacted include...
Piedmont, Spring Garden and Knightens Crossroads.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 3394 8552 3394 8553 3389 8553 3389 8560
      3388 8560 3388 8563 3387 8564 3386 8569
      3394 8574 3398 8574 3404 8562
TIME...MOT...LOC 0045Z 247DEG 11KT 3393 8567

89^GSatterwhite