Severe Thunderstorm Warning 189, NWS Birmingham, AL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BIRMINGHAM AL
645 PM CDT FRI MAY 1 2009

.UPDATE...AVIATION DISCUSSION.

&&

.DISCUSSION...

THE CONVECTIVE SYSTEM OVER NORTHEAST ALABAMA HAS FINALLY
DIMINISHED AND EXITED THE STATE THIS AFTERNOON. ANOTHER MESOSCALE
SYSTEM IS CURRENTLY ONGOING IN CENTRAL TENNESSEE AND HAS BEEN
SHOWING SOME PROPAGATION TOWARDS THE SOUTH AS NEW STORMS DEVELOP
ON THE OUTFLOW. TEMPERATURES THIS AFTERNOON ARE RANGING FROM THE
RAIN COOLED 60S IN THE NORTHEAST TO THE LOWER AND MID 80S IN THE
SOUTH. SCATTERED DIURNAL SHOWERS HAVE DEVELOPED IN THE WARMER
AREAS AND SHOULD BE ONGOING UNTIL SUNSET.

A FRONTAL BOUNDARY WILL REMAIN OFF TO THE NORTH AND WEST OF
ALABAMA THROUGH THE WEEKEND. UPPER FLOW WILL REMAIN ZONAL THROUGH
SATURDAY KEEPING THE MAIN FOCUS OF SHOWERS AND THUNDERSTORMS NORTH
OF THE AREA. ONLY CONCERN WOULD BE DEVELOPING MESOSCALE CONVECTIVE
SYSTEMS PUSHING AN OUTFLOW INTO THE AREA...AFFECTING PRIMARILY THE
NORTHERN COUNTIES. SOME ADDITIONAL DIURNAL ACTIVITY WOULD ALSO BE
POSSIBLE IN THE SOUTH.

BIGGEST CHANGE TO THE FORECAST WILL BE SUNDAY NIGHT THROUGH THE
EARLY PART OF NEXT WEEK. THE 12Z MODELS HAVE BECOME MORE ROBUST
WITH THE APPROACHING SHORTWAVE SUNDAY EVENING. BY MONDAY MORNING
THE FRONTAL BOUNDARY THAT HAD BEEN STALLED TO OUR NORTH WILL BEGIN
PUSHING INTO WEST CENTRAL ALABAMA. SHOWERS AND THUNDERSTORMS
SHOULD BE NUMEROUS ACROSS THE NORTHWESTERN HALF OF THE STATE BY
NOON MONDAY.

CONFIDENCE DROPS ON WHEN THE FRONT WILL PUSH THROUGH...IF IT
PUSHES THROUGH AT ALL. THERE IS A CHANCE THE FRONT COULD GET HUNG
UP OVER SOUTH-CENTRAL OR SOUTHEAST ALABAMA AND EVENTUALLY WASH OUT
BY MID WEEK. THIS DUE TO THE RIDGING OFF THE SOUTHEAST COAST
REMAINING STRONG ENOUGH TO DEFLECT THE SHORTWAVE NORTHEAST AND
PREVENT THE FRONT FROM PUSHING THROUGH. AS A RESULT SCATTERED SHOWERS
AND THUNDERSTORMS WOULD REMAIN IN THE FORECAST UNTIL ANOTHER
SHORTWAVE CLEARS THE AREA LATE IN THE WEEK.

TEMPERATURES THROUGH THE FORECAST WILL BE NEAR 80 IN THE
AFTERNOONS AND LOW TO MID 60S AT NIGHT. DEPENDING ON THE AMOUNT OF
CLOUD COVER AND SHOWER ACTIVITY MONDAY...MANY AREAS MAY REMAIN IN THE
70S FOR AFTERNOON HIGHS ON THAT DAY.

&&

.AVIATION...00Z TAF DISCUSSION.

QUITE A BIT OF THUNDERSTORM ACTIVITY OCCURRING ACROSS NORTHERN
ALABAMA THIS EVENING. HOWEVER...MOST OF THIS ACTIVITY WILL REMAIN
AWAY FROM OUR NORTHERN TAF SITES WITH THE EXCEPTION OF ANB WHERE
STORMS COULD APPROACH ITS VICINITY. THE ONLY PROBLEM EXPECTED
TONIGHT ACROSS ALL SITES WILL BE LOW CLOUDS. THEY ARE EXPECTED TO
DEVELOP AT AROUND 10Z AND REMAIN AS LATE AS 17Z. BY 18Z...MOST AREAS
SHOULD BE BACK TO VFR CONDITIONS.

10/ARM

&&

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

&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BIRMINGHAM AL
100 PM CDT FRI MAY 1 2009

ALZ011>015-017>050-021130-
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-
100 PM CDT FRI MAY 1 2009

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

.DAY ONE...THIS AFTERNOON AND TONIGHT.

ISOLATED THUNDERSTORMS...CAPABLE OF PRODUCING FREQUENT
LIGHTNING...SMALL HAIL...AND WIND GUSTS OVER 30 MPH...WILL BE
POSSIBLE OVER NORTHWEST AND NORTHEAST ALABAMA THROUGH 8 PM.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY.

SEVERE THUNDERSTORMS WILL BE POSSIBLE ON MONDAY.  THE MAIN THREAT
SHOULD BE LARGE HAIL AND DAMAGING WINDS.

NO OTHER HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

ACTIVATION OF STORM SPOTTERS AND EMERGENCY MANAGEMENT IS NOT
ANTICIPATED AT THIS TIME.

03

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
637 PM CDT FRI MAY 1 2009

ALZ017-018-020015-
BLOUNT-ETOWAH-
637 PM CDT FRI MAY 1 2009

...SIGNIFICANT WEATHER ALERT FOR BLOUNT AND ETOWAH COUNTIES UNTIL 715
PM CDT...

AT 635 PM CDT...THE NATIONAL WEATHER SERVICE IS TRACKING STRONG
THUNDERSTORMS ALONG A LINE EXTENDING FROM 5 MILES NORTHWEST OF TABOR
ROAD TO STRAWBERRY...OR ALONG A LINE EXTENDING FROM 15 MILES EAST OF
BOAZ TO 8 MILES SOUTH OF ARAB...MOVING EAST-SOUTHEAST AT 30 MPH.

PEA SIZE HAIL AND WINDS UP TO 40 MPH ARE EXPECTED WITH THESE STORMS.

* LOCATIONS IN OR NEAR THE PATH INCLUDE...
  STRAWBERRY.
  BROOKSVILLE.
  SARDIS CITY.
  SNEAD.
  WILSONIA.
  WALNUT GROVE.

STAY TUNED TO NOAA WEATHER RADIO...COMMERCIAL RADIO...OR YOUR LOCAL
TELEVISION STATIONS FOR LATER STATEMENTS AND POSSIBLE WARNINGS
CONCERNING THIS WEATHER SITUATION.

KSL

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
715 PM CDT FRI MAY 1 2009

ALZ017-020100-
BLOUNT-
715 PM CDT FRI MAY 1 2009

...SIGNIFICANT WEATHER ALERT FOR BLOUNT COUNTY UNTIL 800 PM CDT...

AT 714 PM CDT...THE NATIONAL WEATHER SERVICE IS TRACKING A STRONG
THUNDERSTORM NEAR STRAWBERRY...OR 6 MILES SOUTH OF ARAB...MOVING EAST
AT 25 MPH.

PEA SIZE HAIL AND WINDS UP TO 40 MPH ARE EXPECTED WITH THIS STORM.

* LOCATIONS IN OR NEAR THE PATH INCLUDE...
  STRAWBERRY.
  BROOKSVILLE.
  SUSAN MOORE.
  MCLARTY.

STAY TUNED TO NOAA WEATHER RADIO...COMMERCIAL RADIO...OR YOUR LOCAL
TELEVISION STATIONS FOR LATER STATEMENTS AND POSSIBLE WARNINGS
CONCERNING THIS WEATHER SITUATION.

KSL