Flash Flood Warning 48, NWS Birmingham, AL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BIRMINGHAM AL
349 AM CDT MON SEP 2 2013

.DISCUSSION...

THUNDERSTORMS HAVE BEEN STEADILY INCREASING IN AREAL COVERAGE
OVERNIGHT AS AS SHORT WAVE TROF DIGS SOUTHWARD ACROSS THE MID
MISSISSIPPI VALLEY REGION. BASED ON RADAR TRENDS HAVE RAISED RAIN
CHANCES SIGNIFICANTLY FOR TODAY ACROSS NORTH ALABAMA. THE STORMS
WILL CONTAIN FREQUENT CLOUD TO GROUND LIGHTNING AND HEAVY
RAINFALL. LOCALIZED FLOODING IS POSSIBLE. AS THE SURFACE FRONT
MOVES INTO NORTH ALABAMA LATER TONIGHT...SCATTERED SHOWERS AND
THUNDERSTORMS WILL CONTINUE OVERNIGHT...AND RAIN CHANCES MAY NEED
TO BE RAISED IN SOME AREAS BASED ON LATEST RADAR TRENDS. THE
SURFACE FRONT SHOULD BE NEAR THE I-59 CORRIDOR BY SUNRISE
TUESDAY...SO BEST CHANCE FOR RAIN WILL BE ALONG AND SOUTH OF I-59
DURING THE DAY ON TUESDAY. THE MODELS ARE NOT TAKING THE FRONT AS
FAR SOUTH AS PREVIOUS RUNS...WITH WEAKER NORTHERLY LOW LEVEL
ADVECTION. THE GFS MODEL EVEN KEEPS RAIN ACROSS THE I-85 CORRIDOR
WEDNESDAY THROUGH FRIDAY. THE ECMWF AND DGEX MODELS KEEP THE
DEEPER MOISTURE CLOSER TO THE COASTAL AREAS...SO KEPT A MOSTLY
RAIN FREE FORECAST...BUT DID INTRODUCE SMALL THUNDERSTORM CHANCES
TO THE EXTREME SOUTHEAST COUNTIES ON WEDNESDAY AS THE SURFACE
FRONT STALLS OUT NEAR MONTGOMERY. THE WEAKER ADVECTION BEHIND THE
FRONT TRANSLATES TO HIGHER SURFACE DEWPOINT TEMPERATURES WEDNESDAY
THROUGH FRIDAY...AND RAISED OVERNIGHT LOWS A FEW DEGREES.

A LOW CONFIDENCE FORECAST FOR THE UPCOMING WEEKEND. THE ECMWF
MODEL KEEPS A DRY NORTHWEST FLOW ALOFT DURING THIS TIME
PERIOD...WHILE THE GFS MODEL DEVELOPS AN UPPER TROF AXIS ACROSS
SOUTHEAST ALABAMA...AND BRINGS DEEPER MOISTURE NORTHWARD INTO
SOUTHEAST ALABAMA. PREVIOUS FORECAST TRENDED TOWARDS GFS
SOLUTION...AND DID NOT MAKE ANY SIGNIFICANT CHANGES.

58/ROSE

&&

.AVIATION...
06Z TAF DISCUSSION.

KANB HAS ALREADY DROPPED DOWN TO IFR THANKS TO A SATURATED
BOUNDARY LAYER FROM RAINFALL EARLIER IN THE DAY. EXPECT OTHER
LOCATIONS WILL REMAIN MVFR WITH THE POSSIBILITY OF BRIEF PERIODS
OF IFR CONDITIONS AT KTCL AND KTOI NEAR SUNRISE. THERE ARE
CURRENTLY A FEW ISOLATED THUNDERSTORMS JUST NORTH OF THE I-85
CORRIDOR. HOWEVER...THIS ACTIVITY SHOULD REMAIN TOO ISOLATED TO
MENTION IN THE TAFS. THIS ACTIVITY WILL BE MONITORED OVERNIGHT AND
AMENDMENTS WILL BE MADE IF NECESSARY. FOG SHOULD LIFT SHORTLY
AFTER SUNRISE GIVING WAY TO VFR CONDITIONS. SCATTERED SHOWERS AND
THUNDERSTORMS WILL BE POSSIBLE TOMORROW AND HAVE ADDED VCTS TO ALL
OF THE TERMINALS EXCEPT FOR KTCL...WHERE MOISTURE WILL BE A BIT
LOWER.

05/MA

&&

.PRELIMINARY POINT TEMPS/POPS...
GADSDEN     89  70  89  65  87 /  80  50  30  10  10
ANNISTON    91  71  89  67  88 /  70  50  30  10  10
BIRMINGHAM  90  73  90  69  89 /  60  50  30  10  10
TUSCALOOSA  93  73  92  70  90 /  50  50  30  10  10
CALERA      91  72  91  69  90 /  60  40  30  10  10
AUBURN      91  72  89  69  87 /  50  40  30  20  10
MONTGOMERY  93  73  91  72  92 /  40  40  30  20  10
TROY        93  72  90  71  89 /  50  40  40  20  20

&&

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

&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BIRMINGHAM AL
518 AM CDT MON SEP 2 2013

ALZ011>015-017>050-030300-
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-
518 AM CDT MON SEP 2 2013

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

.DAY ONE...TODAY AND TONIGHT.

FLASH FLOODING IS POSSIBLE THROUGH 9 AM THIS MORNING ACROSS THE
NORTHEAST COUNTIES OF CENTRAL ALABAMA.  HEAVY RAINFALL ASSOCIATED
WITH A SLOW MOVING LINE OF THUNDERSTORMS WILL PRODUCE RAINFALL RATES
OF 1 TO 2 INCHES PER HOUR.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

ACTIVATION OF STORM SPOTTERS AND EMERGENCY MANAGEMENT MAY BE
NECESSARY THIS MORNING ACROSS THE NORTHEAST COUNTIES.