Special Weather Statement, NWS Birmingham, AL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BIRMINGHAM AL
328 PM CDT MON JUN 17 2013

.SHORT TERM...TONIGHT THROUGH THURSDAY.

SATELLITE IMAGERY IS SHOWING A WELL DEFINED UPPER LOW OVER NORTHEAST
OKLAHOMA. SEVERAL IMPULSES ARE ROTATING AROUND THE SOUTHERN AND
EASTERN QUADRANTS OF THE CIRCULATION...WITH ONE IMPULSE CURRENTLY
MOVING THROUGH ALABAMA...AND ANOTHER UPSTREAM IMPULSE APPROACHING
THE MISSISSIPPI RIVER. A SURFACE LOW OVER CENTRAL ARKANSAS WILL
TRACK EAST NORTHEAST TONIGHT ACROSS EXTREME NORTHERN MISSISSIPPI
AND WESTERN TENNESSEE. THE SURFACE LOW WILL PROVIDE A FOCUS MECHANISM
FOR NUMEROUS SHOWERS AND THUNDERSTORMS ACROSS NORTH ALABAMA OVERNIGHT.
HIGH RAIN CHANCES WILL BE NECESSARY TONIGHT AND AGAIN TUESDAY. AS
THE SURFACE LOW PASSES TO THE NORTH OF ALABAMA ON TUESDAY...A WEAK
SURFACE FRONT WILL PUSH SOUTHWARD INTO ALABAMA TUESDAY AFTERNOON
AND EVENING...AND PROVIDE AN ADDITIONAL FOCUS FOR CONVECTIVE
ACTIVITY.

THE SHOWER AND THUNDERSTORM ACTIVITY WILL SHIFT INTO SOUTH CENTRAL
ALABAMA TUESDAY EVENING AS THE SURFACE BOUNDARY MOVES SOUTH OF I-20.
BY WEDNESDAY AND THURSDAY...A DRIER AND MORE STABLE AIR MASS WILL
OVERSPREAD MOST OF CENTRAL ALABAMA...AND ANY RAIN WILL BE CONFINED
TO THE EXTREME SOUTHERN PORTIONS OF CENTRAL ALABAMA. THE AIR MASS
WILL NOT BE ANY COOLER BEHIND FRONT...AND TEMPERATURES WILL RISE
INTO THE UPPER 80S TO LOWER 90S BOTH DAYS IN THE DRY NORTHERLY
FLOW.

58/ROSE

.LONG TERM...FRIDAY THROUGH MONDAY.

DECIDED TO RAISE RAIN CHANCES SLIGHTLY DURING THIS PERIOD. AN
UPPER RIDGE OVER TEXAS WILL EXPAND NORTHEAST. HOWEVER...A MOIST
SOUTHEAST FLOW WILL PREVAIL IN THE LOWER LEVELS. CENTRAL ALABAMA
WILL LIKELY BE JUST FAR ENOUGH AWAY FROM THE RIDGE AXIS TO ALLOW
FOR DIURNAL CONVECTION EACH DAY...ESPECIALLY ACROSS THE SOUTHEAST
COUNTIES. THE WARMEST DAYTIME TEMPERATURES WILL BE ACROSS WEST
ALABAMA...WHICH WILL BE CLOSER TO THE UPPER RIDGE.

58/ROSE

&&

.AVIATION...
18Z TAF DISCUSSION.

SCATTERED TO NUMEROUS SHOWERS/TSTORMS WILL CONTINUE THRU THE EARLY
EVENING HOURS. STORMS COULD PRODUCE WIND GUSTS UP TO 45
MPH...FREQUENT CLOUD-TO-GROUND LIGHTNING...BRIEF HEAVY RAINFALL
AND SMALL HAIL. TIMING OF IMPACTS WILL BE DIFFICULT WELL IN
ADVANCE...SO EXPECT AMENDMENTS THRU THE DAY.

THERE COULD BE A BREAK IN THE ACTIVITY LATE THIS EVENING AND EARLY
TONIGHT AS DAYTIME CONVECTION SHOULD SLOWLY DIMINISH. WITH LOW
LEVEL MOISTURE STILL PLENTIFUL...CIGS SHOULD LOWER TO MVFR ACROSS
MUCH OF THE AREA LATER TONIGHT. WILL HAVE TO MONITOR FOR THE POSSIBILITY
OF EVEN LOWER CIGS OVERNIGHT. ANOTHER ROUND OF TSTORMS WILL MOVE
IN FROM THE N/NW LATE TONIGHT/EARLY TUESDAY AS A FRONTAL BOUNDARY
APPROACHES.

NOTE: DUE TO ONGOING MAINTENANCE AT ANB OBS ARE NOT BEING
TRANSMITTED. WILL INCLUDE *AMD NOT SKED* AT THIS TIME. OBS SHOULD
START COMING BACK IN LATER THIS AFTERNOON WHEN THE WORK HAS
BEEN COMPLETED.

19

&&

.PRELIMINARY POINT TEMPS/POPS...
GADSDEN     70  84  69  89  61 /  80  80  40  10  10
ANNISTON    71  84  70  89  64 /  70  80  50  10  10
BIRMINGHAM  73  84  70  89  66 /  70  80  40  10  10
TUSCALOOSA  73  86  71  92  66 /  70  80  50  20  10
CALERA      71  84  70  89  67 /  70  80  50  20  10
AUBURN      69  84  71  89  67 /  50  60  60  20  20
MONTGOMERY  73  89  73  92  68 /  50  60  60  30  20
TROY        71  88  73  91  66 /  40  60  60  30  20

&&

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

&&