Flash Flood Warning 26, NWS Birmingham, AL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BIRMINGHAM AL
645 AM CDT SAT MAY 29 2010

.UPDATE...FOR 12Z AVIATION.

&&

.DISCUSSION...

UPPER LOW IS SPINNING OVER NORTH CENTRAL MISSISSIPPI THIS
MORNING...WITH ISOLATED SHOWER/THUNDERSTORM ACTIVITY ONGOING OVER
PORTIONS OF MISSISSIPPI AND ALABAMA. SEEING AN AREA OF CLEARING
ACROSS THE SOUTHWEST...WHICH SHOULD CONTINUE TO SPREAD EAST AND
NORTH. PATTERN WILL REMAIN RATHER UNCHANGED OVER THE HOLIDAY
WEEKEND...AS THE UPPER LOW CONTINUES TO ROTATE TO OUR WEST. EXPECT
WIDESPREAD THUNDERSTORM DEVELOPMENT EACH DAY...WITH ACTIVITY
BECOMING MORE ISOLATED DURING THE OVERNIGHT PERIOD.

FOR TODAY...ADDITIONAL CLOUD COVER AND RAIN WILL KEEP HIGH
TEMPERATURES IN THE MID 80S THIS AFTERNOON. HOWEVER...CLEARING THIS
MORNING WILL ALLOW TEMPERATURES TO WARM INTO THE LOW 80S BY MID
DAY...MEETING CONVECTIVE TEMPS. EXPECT INITIAL DEVELOPMENT TODAY TO
BE IN THE AREA OF CLEARING ACROSS THE SOUTH...CLOSE TO AN INVERTED
SFC TROUGH STRETCHING NORTHWARD INTO EAST CENTRAL ALABAMA FROM AN
AREA OF LOW PRESSURE NEAR THE GULF COAST. WITH SO MANY LEFTOVER
BOUNDARIES FROM FRIDAYS ACTIVITY THOUGH...ACTIVITY WILL QUICKLY
BECOME WIDESPREAD. GIVEN THE COOL UPPER LEVEL TEMPS AND MID LEVEL
LAPSE RATES...AIRMASS WILL BE SUPPORTIVE OF WIDESPREAD STRONG
TSTORMS AND ISOLATED SEVERE. WITH PW VALUES OVER 1.5
INCHES...HEAVY RAINFALL WILL ALSO BE POSSIBLE.

CLOSED LOW WEAKENS BY TUESDAY AND OPENS AS UPPER LEVEL FLOW ACROSS
THE SOUTHEAST BECOMES MORE ZONAL. AIRMASS ACROSS THE AREA WILL
REMAIN UNSETTLED AND MOIST. NO REASON TO THINK AT LEAST SCT ACTIVITY
WILL NOT BE POSSIBLE EACH DAY. MODELS SHOW A TRANSITION TO TROUGHING
ACROSS THE EASTERN CONUS NEXT WEEKEND...WITH A SHORTWAVE ENHANCING
RAIN CHANCES BY THE END OF NEXT WEEK. THIS IS FOLLOWED BY A STRONG
FRONTAL PASSAGE...UNLIKELY FOR THE BEGINNING OF JUNE. GIVEN THE
UNCERTAINTY IN THIS PATTERN CHANGE WILL MAINTAIN SCHC/CHC POPS FOR
NOW.

TEMPERATURES BY MIDWEEK WILL BE BACK TO JUST ABOVE NORMAL AS
RAIN COVERAGE IS EXPECTED TO BE LESS. HIGHS WILL BE AROUND 90 AND
OVERNIGHT LOWS IN THE 60S.

14

&&

.AVIATION...12Z TAF DISCUSSION.

UPPER LOW CENTERED IN MS HAS PRODUCING ENOUGH LIFT FOR
SCATTERED TSRA NEAR I-65 CORRIDOR AT 12Z. ALTHOUGH EXTENSIVE VFR
CLOUD COVER EXISTS FROM YESTERDAYS AND THIS MORNINGS
CONVECTION...PROXIMITY OF UPPER LOW...SOME EXPECTED CLEARING...AND
HIGH PW WILL ALLOW WIDESPREAD TSRA TO REDEVELOP.
HOWEVER...EXTREMELY DIFFICULT TO PINPOINT WHICH AIRPORTS WILL BE
DIRECTLY AFFECTED BETWEEN 15Z-01Z. ON THE FLIP SIDE...AM VERY
CONFIDENT THAT MOST LOCATIONS WILL HAVE AT LEAST VCNTY TSRA AND THUS
PLACED THIS INTO TAFS. WITH EXPECTED CLOUD COVER LINGERING THROUGH
NIGHT AGAIN KEEPING RADIATIONAL COOLING TO A MINIMUM...DO NOT
ANTICIPATE WIDESPREAD BR. STEFKOVICH

&&

.PRELIMINARY POINT TEMPS/POPS...
GADSDEN     85  66  83  65  86 /  70  30  60  30  60
ANNISTON    86  68  83  66  85 /  70  30  60  30  60
BIRMINGHAM  85  69  84  68  85 /  70  30  60  30  60
TUSCALOOSA  86  67  86  67  87 /  70  30  60  30  50
CALERA      85  67  84  67  85 /  70  30  60  30  60
AUBURN      85  64  82  65  86 /  60  30  60  30  60
MONTGOMERY  88  68  86  68  87 /  70  30  60  30  60
TROY        87  68  85  66  87 /  70  30  60  30  60

&&

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

&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BIRMINGHAM AL
1122 AM CDT SAT MAY 29 2010

ALZ011>015-017>050-301600-
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-
1122 AM CDT SAT MAY 29 2010

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

.DAY ONE...THIS AFTERNOON AND TONIGHT.

THUNDERSTORMS ARE EXPECTED TO INCREASE IN COVERAGE ACROSS CENTRAL
ALABAMA THROUGH THE AFTERNOON.  THERE IS A POTENTIAL OF STRONG TO
SEVERE THUNDERSTORMS FROM NOON TO 10 PM.  THE AREA WITH THE
GREATEST THREAT OF SEVERE THUNDERSTORMS...INCLUDING THE RISK OF
DAMAGING WINDS AND LARGE HAIL...IS FROM THE CITIES OF
CARROLLTON...TUSCALOOSA...BIRMINGHAM...SYLACAUGA...AND ROANOKE...
SOUTHWARD. THE STORMS SHOULD REACH THEIR PEAK IN COVERAGE AND
INTENSITY BETWEEN 3 AND 6 PM...BUT MAY CONTINUE ON WELL AFTER DARK.

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

STRONG STORMS WILL BE POSSIBLE ON SUNDAY FROM 8 AM TO 8 PM. THE
MAIN THREATS WILL BE WIND GUSTS OF 40 TO 50 MPH AND PENNY SIZE HAIL.

.SPOTTER INFORMATION STATEMENT...

ACTIVATION OF STORM SPOTTERS AND EMERGENCY MANAGEMENT MAY BE NEEDED
THIS AFTERNOON.

61

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
936 AM CDT SAT MAY 29 2010

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0546 PM     TSTM WND DMG     2 W WEDGEWORTH          32.81N 87.80W
05/28/2010                   HALE               AL   PUBLIC

            TREES WERE BLOWN DOWN ON CLEAR CREEK ROAD.

&&

61

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
956 AM CDT SAT MAY 29 2010

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0558 PM     TSTM WND DMG     4 SSW OAKMAN            33.66N 87.42W
05/28/2010                   WALKER             AL   PUBLIC

            TREES WERE BLOWN DOWN ON BLUE WATER ROAD.

0559 PM     TSTM WND DMG     5 S OAKMAN              33.64N 87.40W
05/28/2010                   WALKER             AL   PUBLIC

            TREES WERE BLOWN DOWN ON BETHEL ROAD.

&&

61

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
1045 AM CDT SAT MAY 29 2010

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0508 PM     TSTM WND DMG     4 ESE ONEONTA           33.93N 86.41W
05/28/2010                   BLOUNT             AL   LAW ENFORCEMENT

            TREES DOWN ON PUTMAN ROAD, COUNTY HIGHWAY 20, AND ROBIN
            HILL ROAD.

&&

KSUMRALL

PRELIMINARY LOCAL STORM REPORT...CORRECTED
NATIONAL WEATHER SERVICE BIRMINGHAM AL
1105 AM CDT SAT MAY 29 2010

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0430 PM     TSTM WND DMG     2 WNW ATTALLA           34.04N 86.13W
05/28/2010                   ETOWAH             AL   EMERGENCY MNGR

            TREES DOWN AT THE IVALEE COMMUNITY SCHOOL. CORRECTED
            TIME.

&&

61

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
1249 PM CDT SAT MAY 29 2010

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1240 PM     HEAVY RAIN       AUBURN                  32.59N 85.48W
05/29/2010  E0.00 INCH       LEE                AL   PUBLIC

            HEAVY RAINFALL CREATING LOCALIZED STREET FLOODING ON
            MAGNOLIA AVENUE IN AUBURN.

&&