FXUS64 KBMX 282340
AFDBMX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BIRMINGHAM AL
540 PM CST SAT NOV 28 2009

.UPDATE...AVIATION DISCUSSION.

&&

.DISCUSSION...

HIGH LEVEL CLOUDS ASSOCIATED WITH A SHORT WAVE MOVING ACROSS THE 
AREA TODAY HAVE KEPT AFTERNOON TEMPERATURES IN THE LOW 60S ACROSS 
MUCH OF THE AREA. AS HIGH PRESSURE SHIFTS EASTWARD TONIGHT...WINDS 
WILL BECOME MORE SOUTHERLY. IN ADDITION...HIGH TO MID LEVEL CLOUDS 
WILL HANG AROUND...KEEPING OVERNIGHT LOWS 4 TO 5 DEGREES WARMER THAN 
LAST NIGHT. MOST LOCATIONS WILL COOL TO AROUND 40 DEGREES...WITH 
PLACES IN THE NORTH AND TYPICALLY COOLER LOCATIONS FALLING INTO THE 
MID TO UPPER 30S. 

SOUTHERLY FLOW WILL INCREASE TOMORROW AHEAD OF AN APPROACHING SHORT 
WAVE MOVING ACROSS THE MIDWEST...DRAGGING A FRONT ACROSS THE 
MISSISSIPPI RIVER AND INTO WEST CENTRAL ALABAMA BY EARLY MONDAY 
MORNING. FOR SUNDAY AFTERNOON...EXPECT INCREASING CLOUDS FROM THE 
WEST AND AFTERNOON HIGHS IN THE 60S. RAINFALL ASSOCIATED WITH THE 
FRONT WILL MOVE INTO NORTHWEST CENTRAL ALABAMA TOMORROW NIGHT...WITH 
MOST OF THE ACTIVITY REMAINING TO OUR WEST UNTIL AFTER MIDNIGHT. 
RAIN WILL SPREAD ACROSS THE AREA MONDAY...ENDING ACROSS THE 
NORTHWEST MONDAY AFTERNOON...AND THE SOUTHEAST MONDAY EVENING. 
CONVERGENCE ALONG THE FRONT WILL BE RATHER WEAK...AND GIVEN THE 
AMOUNT OF CLOUD COVER AHEAD OF THE FRONT...INSTABILITIES AND THE 
CHANCE OF THUNDER WILL BE LOW. MONDAY MORNING LOWS WILL BE IN THE 
UPPER 40S AND 50S WITH AFTERNOON HIGHS IN THE LOW 50S TO MID 60S. 

STRONG MID LEVEL FLOW WILL PUSH THE FRONT TO THE GULF COAST MONDAY 
NIGHT AS HIGH PRESSURE MOVES IN THE AREA. WILL SEE SOME 
CLEARING...MAINLY IN THE NORTH MONDAY NIGHT AND WITH COLD AIR 
ADVECTING INTO THE AREA...LOWS WILL BE IN THE MID 30S TO LOW 40S. A 
QUICK BREAK IN THE ACTION IS EXPECTED ON TUESDAY AS HIGH PRESSURE 
SHIFTS TO OUR EAST...ALLOWING LOW LEVEL FLOW TO BECOME EASTERLY TO 
SOUTHEASTERLY BY TUESDAY NIGHT. HIGHS TUESDAY WILL BE AROUND 60.

A CLOSED UPPER LEVEL LOW MOVING ACROSS THE SOUTHERN PLAINS TUESDAY 
WILL SPARK SURFACE LOW DEVELOPMENT IN THE NORTHERN GULF COAST. THIS 
LOW IS EXPECTED TO MOVE NORTHWARD TUESDAY NIGHT AND 
WEDNESDAY...BRINGING A SIGNIFICANT CHANCE OF RAIN TO CENTRAL 
ALABAMA. THE EU IS SLOWER IN EJECTING THE CLOSED UPPER LOW 
NORTHEASTWARD...AND BRINGS A SLIGHTLY WEAKER SFC LOW NORTHWARD OVER 
MS. ALTHOUGH THE OPER GFS DEVELOPS A STRONGER /STRONGER THAN MOST 
GFS ENS MEMBERS/ SFC LOW QUICKER...THE LATEST RUN HAS SHIFTED THE
TRACK OF THE LOW WESTWARD. WILL TAKE A BLEND OF THE EU AND ENS
MEMBERS AND INCREASE POPS TUESDAY NIGHT...AND WILL ADD IN THUNDER
FOR THE FAR SOUTHEAST. CHANCES OF THUNDER WILL BE DEPENDENT OF THE
TRACK OF THE SURFACE LOW AND HOW FAR NORTHWARD THE WARM FRONT
LIFTS BEFORE THE SYSTEM LIFTS NORTHEASTWARD AND THE COLD FRONT
SWINGS THROUGH THE AREA.

SURFACE LOW LIFTS NORTH OF THE AREA WEDNESDAY NIGHT...WITH LOW LEVEL 
FLOW BECOMING WESTERLY...AND FINALLY NORTHERLY THURSDAY AS THE UPPER 
LEVEL TROUGH LIFTS TO THE NORTHEAST. COLD AIR WILL FILTER INTO THE 
AREA AS HIGH PRESSURE MOVES INTO THE SOUTHEAST. DAYTIME HIGHS ON 
THURSDAY WILL BE IN THE UPPER 40S ACROSS THE NORTH AND MID 50S IN 
THE SOUTH. FRIDAY WILL BE THE COLDEST MORNING WITH LOWS IN THE UPPER 
20S TO LOW 30S. TEMPERATURES WILL WARM INTO THE MID 50S FRIDAY 
AFTERNOON WITH WESTERLY WINDS AND CLEARING SKIES.

14

&&

.AVIATION...00Z TAF DISCUSSION.

CONFIDENCE REMAINS HIGH IN HAVING NO WEATHER RELATED AVIATION 
CONCERNS OVER THE NEXT 24 HOURS.  MID TO HIGH LEVEL CLOUDS WILL 
CONTINUE TO STREAM IN FROM THE WEST...BUT CEILINGS WILL STAY AT OR 
ABOVE 10K FEET THROUGH THE PERIOD.

/61/

&&

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

&&

$$