Severe Thunderstorm Warning 227, NWS Birmingham, AL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BIRMINGHAM AL
326 PM CDT SAT MAY 13 2006

.DISCUSSION...DETERMINING THE CHANCES FOR SEVERE WEATHER
LATE THIS AFTERNOON AND TONIGHT IS THE MAIN CHALLENGE. AT THE
MOMENT...APPEARS THE THREAT FOR SEVERE WEATHER ACROSS THE AREA
HAS DIMINISHED A BIT AS THE INITIATION POINT FOR NEW DEVELOPMENT
OF SHOWERS AND STORMS REMAINS UNCERTAIN. IF SEVERE STORMS
DEVELOP...THEY WILL LIKELY OCCUR BETWEEN 7 PM CDT AND
7 AM CDT...ROUGHLY 3 TO 6 HOURS LATER THAN PREVIOUSLY THOUGHT.

MODELS IN THE SHORT TERM INITIALIZED POORLY ACROSS ALABAMA.
GENERALLY...WILL USE A BLEND OF MODEL DATA. WILL MAKE SOME
CHANGES TO THE PREVIOUS FORECAST...BUT NOTHING TOO MAJOR.

AT 315 PM CDT...A WEAKENING AREA OF SHOWERS AND THUNDERSTORMS
ALONG A MID LEVEL MOISTURE CONVERGENCE ZONE WERE MOVING OUT OF
EAST ALABAMA. THE AIR WAS STABLE AND COOL FROM RAIN AND CLOUDS
ALONG A TUSCALOOSA TO AUBURN LINE WHERE TEMPERATURES WERE IN
THE 60S. THE AIR WAS UNSTABLE SOUTH OF AN ALICEVILLE TO TROY LINE
AND NORTH OF A HAMILTON TO WEDOWEE LINE WHERE SUN HAS BOOSTED
TEMPERATURES INTO THE 70S.

A SURFACE BOUNDARY/COLD FRONT STRETCHED FROM NEAR LITTLE ROCK
ARKANSAS TO LEXINGTON KENTUCKY WILL LIKELY SERVE AS THE BEST
INITIATION POINT FOR REDEVELOPMENT OF SHOWERS AND STORMS TONIGHT.

FOR THE REST OF THIS AFTERNOON...CURRENT SHOWERS SOUTHEAST OF
BIRMINGHAM WILL CONTINUE TO WEAKEN AND MOVE INTO GEORGIA BY
5 PM CDT. SKIES WILL CLEAR WEST TO EAST AS DRIER AIR MOVES IN.

DETERMINING WHERE AND IF NEW SHOWERS AND THUNDERSTORMS DEVELOP
LATE THIS AFTERNOON AND EVENING REMAINS VERY DIFFICULT.
THROUGH 7 PM CDT...APPEARS THERE ARE TWO LOCATIONS WHERE NEW
SHOWERS AND STORMS DEVELOP. THE FIRST AREA IS NORTH OF A VERNON
TO HEFLIN LINE WHERE THE MID LEVEL CAP IS WEAKEST AND AFTERNOON
SUN HAS WARMED TEMPERATURES INTO THE MID 70S...AND THE SECOND
AREA MAY BE ALONG A PRONOUNCED OUTFLOW BOUNDARY STRETCHING
ALONG A DEMOPOLIS TO DOTHAN LINE. CONFIDENCE OF DEVELOPMENT
THROUGH 7 PM CDT REMAINS LOW IN THESE LOCATIONS...HOWEVER IF
THUNDERSTORMS CAN DEVELOP...LARGE HAIL UP TO THE SIZE OF GOLF
BALLS IS THE MAIN CONCERN...THOUGH DAMAGING WINDS UP TO 60 MPH
MAY BE POSSIBLE AS THE AIR WILL BE UNSTABLE.

LATER TONIGHT...BELIEVE THE SURFACE BOUNDARY/COLD FRONT WILL
SERVE AS THE MAIN SOURCE TO PRODUCE SHOWERS AND STORMS.
STORMS WILL DEVELOP ALONG THIS FRONT IN TENNESSEE AROUND SUNSET.
THESE STORMS WILL LIKELY MOVE SOUTHEAST ALONG THE FRONT...
AFFECTING LOCATIONS NORTH OF INTERSTATE 20 BETWEEN 10 PM CDT
AND 3 AM CDT...AND POINTS SOUTH AFTER 3 AM CDT. AGAIN...LARGE HAIL
IS THE MAIN THREAT WITH A FEW STORMS...THOUGH WIDESPREAD SEVERE IS
NOT EXPECTED. WILL LEAN TOWARDS THE HIGHER SIDE OF GUIDANCE FOR
RAIN CHANCES TONIGHT.

WILL HAVE TO WATCH TO SEE IF A COMPLEX OF SHOWERS AND
THUNDERSTORMS DEVELOPS OVER CENTRAL MISSISSIPPI AFTER MIDNIGHT
TONIGHT THEN MOVE ACROSS AREAS SOUTH OF INTERSTATE 20 AFTER
3 AM CDT AS SOME MODELS INDICATE. AGAIN...SOME LARGE HAIL MAY
OCCUR WITH THESE STORMS. CONFIDENCE OF THIS OCCURRING REMAINS LOW.

ON SUNDAY...THE FRONT/SURFACE BOUNDARY WILL CONTINUE TO MOVE SOUTH
AND BRING SHOWERS AND THUNDERSTORMS...MAINLY IN THE MORNING...TO
LOCATIONS SOUTH OF INTERSTATE 20. WILL HAVE TO WATCH FOR THE
POTENTIAL OF STRONG/SEVERE STORMS IN THE MONTGOMERY/AUBURN/
PHENIX CITY AREAS AS THE AIR IS FORECAST TO BE UNSTABLE WITH
LIFTED INDICES -1 TO -4. LOCATIONS ALONG AND NORTH OF
INTERSTATE 20 INCLUDING BIRMINGHAM...TUSCALOOSA...AND
ANNISTON SHOULD BE DRY FOR MOST...IF NOT ALL DAY.

SUNDAY NIGHT...WILL KEEP A LOW CHANCE FOR MAINLY EVENING
SHOWERS AND STORMS ALONG AND SOUTH OF INTERSTATE 85 WHERE THE
FRONT/SURFACE BOUNDARY IS EXPECTED TO LINGER. DRY AND CLEARING
CONDITIONS ARE FORECAST ELSEWHERE.

MONDAY APPEARS TO BE DRY...BUT COOL WITH HIGHS IN THE 67 TO 77
DEGREE RANGE AND LOWS IN THE 44 TO 54 DEGREE RANGE. MOSTLY CLEAR
CONDITIONS CAN BE EXPECTED SOUTH OF INTERSTATE 20...WHILE AFTERNOON
CLOUDS MAY THICKEN NORTH OF INTERSTATE 20...CLOSER TO THE UPPER
LOW TO THE NORTH.

TUESDAY AND WEDNESDAY...WILL KEEP CHANCES FOR SHOWERS AND
THUNDERSTORMS BOTH DAYS AS THE UPPER LOW ROTATES A DISTURBANCE
THR0UGH THE AREA ON THESE DAYS. WILL LOWER TEMPERATURES SLIGHTLY
AS WELL.

THURSDAY AND BEYOND...DRY AND WARMER WEATHER IS EXPECTED AS THE
UPPER LOW TO OUR NORTH MOVES EAST. NORMAL TEMPERATURES WITH HIGHS
IN THE LOWER 80S AND LOWS IN THE MID TO UPPER 50S ARE FORECAST
BY FRIDAY. THE NEXT SYSTEM MAY APPROACH THE AREA LATE SATURDAY...
BUT CONFIDENCE REMAINS LOW WITH THIS FEATURE.

&&

.PRELIMINARY POINT TEMPS/POPS...
GADSDEN     52  72  43  68 /  50  20  10  10
ANNISTON    55  73  45  69 /  50  20  10  10
BIRMINGHAM  56  72  47  69 /  50  20  10  10
TUSCALOOSA  56  75  46  72 /  50  20  10  10
CALERA      56  73  47  69 /  50  20  10  10
AUBURN      58  74  52  71 /  30  50  20  10
MONTGOMERY  59  77  54  75 /  30  50  20  10
TROY        59  76  54  75 /  20  50  30  10

&&

.BMX WATCHES/WARNINGS/ADVISORIES...
AL...NONE.

&&

MBS/91

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BIRMINGHAM AL
126 PM CDT SAT MAY 13 2006

ALZ011>015-017>050-141130-
AUTAUGA-BARBOUR-BIBB-BLOUNT-BULLOCK-CALHOUN-CHAMBERS-CHEROKEE-
CHILTON-CLAY-CLEBURNE-COOSA-DALLAS-ELMORE-ETOWAH-FAYETTE-GREENE-HALE-
JEFFERSON-LAMAR-LEE-LOWNDES-MACON-MARENGO-MARION-MONTGOMERY-PERRY-
PICKENS-PIKE-RANDOLPH-RUSSELL-SHELBY-ST CLAIR-SUMTER-TALLADEGA-
TALLAPOOSA-TUSCALOOSA-WALKER-WINSTON-
126 PM CDT SAT MAY 13 2006

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE COUNTIES SERVED BY
THE NATIONAL WEATHER SERVICE OFFICE IN BIRMINGHAM.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

A FEW STRONG TO SEVERE THUNDERSTORMS WILL BE POSSIBLE THIS AFTERNOON
AND OVERNIGHT ACROSS CENTRAL ALABAMA.  LARGE HAIL AND DAMAGING WINDS
ARE THE MAIN THREATS FROM THESE STORMS.  STORMS WILL INITIATE BY
AROUND 4 PM...AND ARE EXPECTED TO CONTINUE WELL INTO THE OVERNIGHT
HOURS.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY.

A FEW STRONG STORMS ARE POSSIBLE MAINLY THROUGH NOON ON SUNDAY. THE
GREATEST POTENTIAL EXISTS SOUTH OF INTERSTATE 20 AND THE MAIN THREAT
WILL BE SMALL HAIL AND GUSTY WINDS. A COLD FRONT WILL PUSH THROUGH
SOUTHERN ALABAMA SUNDAY AFTERNOON ENDING THE CHANCE OF STRONG
STORMS.

.SPOTTER INFORMATION STATEMENT...

ACTIVATION OF STORM SPOTTERS AND EMERGENCY MANAGEMENT PERSONNEL MAY
BE REQUIRED THROUGH EARLY SUNDAY.

75