Special Weather Statement, NWS Birmingham, AL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BIRMINGHAM AL
1245 PM CDT TUE AUG 9 2011

.UPDATE...
18Z AVIATION.

&&

.DISCUSSION...

SHOWERS CONTINUE TO WEAKEN ACROSS THE NORTHWEST THIS MORNING IN
ASSOCIATION WITH AN MCV MOVING EWD ACROSS THE AREA. THINGS HAVE
BEEN PRETTY CALM SO FAR...BUT EXPECT STORMS TO START FIRING IN THE
NEXT COUPLE OF HOURS AS PEAK HEATING PROGRESSES. DIURNALLY DRIVEN
CONVECTION WILL BE A LITTLE SLOWER TO DEVELOP ACROSS THE NORTHERN
HALF AT FIRST..THANKS TO ONGOING CLOUD COVER. HOWEVER...THERE WILL
BE AT LEAST ONE IF NOT MORE WAVES/ROUNDS OF SHOWERS/STORMS THAT
WILL MOVE SEWD ACROSS THE CWA LATER TODAY AS A SHORTWAVE TROUGH
TRAVERSES THE AREA. SUFFICIENT INSTABILITY AND BULK SHEAR VALUES
OF 25 TO 30 THIS AFTN WILL LEAD TO THE POSSIBILITY OF SEVERE
STORMS ACROSS CENTRAL AL...AND SPC STILL HAS THE ENTIRE CWA IN A
SLIGHT RISK.

ONGOING FORECAST LOOKS ON TRACK FOR THE MOST PART...SO HAVE NOT
MADE ANY MAJOR CHANGES. DID MAKE SOME SLIGHT ADJUSTMENTS TO THE
POP AND SKY GRIDS. UPDATES ARE OUT.

19

&&

.AVIATION...
18Z TAF DISCUSSION.

DAYTIME HEATING AND OLD OUTFLOW BOUNDARIES...ALONG WITH AN UPPER
LEVEL SHORTWAVE PUSHING ACROSS THE AREA...WILL BE THE CONTRIBUTING
FACTORS TO SCATTERED TO NUMEROUS CONVECTION THIS AFTN/EVNG. COVERAGE
IS EXPECTED TO BE THE GREATEST ACROSS THE CENTRAL PORTIONS OF THE
CWA. TIMING WILL BE VERY DIFFICULT UNTIL TSTM COMPLEXES/LINES BEGIN
TO FORM. FOR NOW WILL KEEP PREVAILING VCTS IN FOR ALL TERMINALS THRU
02Z-04Z. SOME STORMS COULD BECOME SEVERE...PRODUCING DAMAGING
WINDS...HEAVY RAIN...AND FREQUENT CLOUD-TO-GROUND LIGHTNING.

ACTIVITY SHOULD BEGIN TO WEAKEN AND DIMINISH BY LATE EVNG...WITH
LEFTOVER CIRRUS OVERNIGHT. DUE TO CONTINUED LOW LEVEL MOISTURE AND
RAINFALL EXPECTED TODAY...IF SKIES CLEAR ENOUGH TONIGHT THEN PATCHY
FOG WILL LIKELY DEVELOP. THEREFORE...WILL KEEP MENTION OF MVFR VIS
IN FOR MOST SITES BETWEEN 10Z AND 12Z. RAIN CHANCES DECREASE
SIGNIFICANTLY ON WED AS SLIGHTLY DRIER AIR BRIEFLY MOVES INTO THE
REGION. FEW TO SCT CU WILL DEVELOP...BUT RAIN CHANCES ARE TOO LOW TO
MENTION ANY WX AT THIS TIME.

19

&&

.PRELIMINARY POINT TEMPS/POPS...
GADSDEN     90  70  93  72  92 /  60  30  20  20  30
ANNISTON    90  70  94  72  93 /  60  30  20  20  30
BIRMINGHAM  90  72  94  75  94 /  60  30  20  20  30
TUSCALOOSA  93  72  96  75  96 /  60  30  20  20  30
CALERA      91  72  94  74  93 /  60  30  20  20  30
AUBURN      93  72  95  75  94 /  50  30  20  20  30
MONTGOMERY  95  74  96  76  95 /  50  30  20  20  30
TROY        94  73  96  75  95 /  50  30  20  20  30

&&

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

&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BIRMINGHAM AL
107 PM CDT TUE AUG 9 2011

ALZ011>015-017>050-101807-
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-
107 PM CDT TUE AUG 9 2011

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

.DAY ONE...THIS AFTERNOON AND TONIGHT.

SEVERE THUNDERSTORMS ARE POSSIBLE ACROSS ALL OF CENTRAL ALABAMA
TODAY...MAINLY THROUGH 9 PM THIS EVENING. THE HAZARDOUS THREATS
INCLUDE DAMAGING STRAIGHT LINE WIND GUSTS...FREQUENT LIGHTNING AND
HEAVY RAIN.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

ACTIVATION OF STORM SPOTTERS AND EMERGENCY MANAGEMENT MAY BECOME
NECESSARY THIS AFTERNOON AND EVENING.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
149 PM CDT TUE AUG 9 2011

ALZ040-042-091930-
DALLAS AL-LOWNDES AL-
149 PM CDT TUE AUG 9 2011

...SIGNIFICANT WEATHER ADVISORY FOR NORTHERN LOWNDES AND SOUTHERN
DALLAS COUNTIES UNTIL 230 PM CDT...

AT 145 PM CDT...THE NATIONAL WEATHER SERVICE WAS TRACKING STRONG
THUNDERSTORMS ALONG A LINE EXTENDING FROM SELMONT-WEST SELMONT TO
ORRVILLE...AND MOVING SOUTHEAST AT 20 MPH.

WIND GUSTS UP TO 50 MPH ARE EXPECTED WITH THESE STORMS...ALONG WITH
FREQUENT DANGEROUS LIGHTNING.

LOCATIONS IN OR NEAR THE PATH OF THESE STORMS INCLUDE...
  MOSSES...
  FIVE POINTS...
  TYLER...
  SARDIS...
  BENTON...

&&

LAT...LON 3206 8714 3231 8743 3242 8693 3237 8681
      3235 8681 3234 8682 3231 8681 3232 8678
      3235 8677 3222 8648
TIME...MOT...LOC 1849Z 296DEG 16KT 3234 8697 3229 8723

27