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000
FXUS64 KBMX 101101
AFDBMX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BIRMINGHAM AL
500 AM CST WED FEB 10 2010

.UPDATE...FOR AVIATION DISCUSSION.

&&

.SHORT TERM...TODAY THROUGH THURSDAY.

A COUPLE OF DRY AND PARTLY SUNNY DAYS ARE IN STORE FOR TODAY AND
TOMORROW. WINDS LOOK TO BE A LITTLE ON THE BREEZY SIDE AGAIN
TODAY...ESPECIALLY ACROSS THE EASTERN HALF OF THE FORECAST
AREA...WITH GUSTS UP TO 25 MPH. A WIND ADVISORY WILL BE NEEDED FOR
THE LATE MORNING AND AFTERNOON HOURS.

.LONG TERM...FRIDAY THROUGH WEDNESDAY.

THE MAIN WEATHER EVENT...AND BY FAR THE BIGGEST FORECAST
CHALLENGE...WILL BE THE SYSTEM MOVING THROUGH RATHER QUICKLY ON
THURSDAY NIGHT AND FRIDAY. THE TIMING OF SYSTEM HASN`T REALLY
CHANGED FROM YESTERDAY. DECIDED TO STICK WITH THE GFS AND EUROS
TIMING AS THEY ARE IN FAIRLY GOOD AGREEMENT...WHEREAS THE NAM
SOLUTION IS QUITE A BIT SLOWER.

THE LATEST GUIDANCE FROM BOTH THE EURO AND GFS HAS BROUGHT THE TRACK
OF THE LOW FARTHER NORTH...ESPECIALLY AS EXPECTED FROM THE GFS...SO
IN RESPONSE TO THE CHANGES IN THE TRACK...THE MOISTURE WILL BE
TRANSPORTED FARTHER NORTH AS WELL. RIGHT NOW IT LOOKS TO BE MAINLY A
SNOW EVENT ACROSS THE MAJORITY OF THE FORECAST AREA.
HOWEVER...LOOKING AT THE THICKNESS VALUES...THERE IS STILL A CHANCE
OF A RAIN/SNOW MIX ACROSS THE EXTREME SOUTH AS WARMER TEMPS COULD
MAKE THEIR WAY INTO THE LOWER BOUNDARY LAYER OVER PART OF THE
REGION. IF MODELS CONTINUE THE NORTHWARD TREND THEN THE RAIN/SNOW
LINE WILL SET UP FARTHER NORTH THAN CURRENTLY FORECAST AND IT COULD
END UP BEING AN ALL RAIN EVENT ACROSS MUCH OF THE SOUTH. BUT FOR
NOW JUST GOING TO KEEP SNOW WORDING IN FOR THE ENTIRE AREA DUE TO
THE POTENTIAL FOR DYNAMICAL COOLING EFFECTS TO END UP DICTATING THE
EVENT OUTCOME. A BAND OF HEAVIER SNOW WILL LIKELY SET UP SOMEWHERE
ACROSS CENTRAL ALABAMA BUT THE EXACT PLACEMENT OF THE BAND...ALONG
WITH MANY OTHER THINGS...WILL ALL DEPEND ON WHERE THE TRACK OF THE
LOW WILL BE. RIGHT NOW WOULD HAVE TO THINK THAT BAND WOULD SET UP
BETWEEN BHM AND MGM. DEFINITELY GOING TO HAVE TO KEEP A CLOSE EYE ON
FUTURE MODEL GUIDANCE FOR EVEN THE SMALLEST OF CHANGES IN THE
FORECASTED TRACK OF THE LOW AND THE AMOUNT OF MOISTURE ASSOCIATED
WITH THIS SYSTEM. ONCE AGAIN...AS WITH ALL SYSTEMS...THE MESOSCALE
DETAILS WILL BE THE MAIN PLAYER.

MODELS SHOW ANOTHER LOW PRESSURE SYSTEM PUSHING THROUGH THE REGION
ON SUNDAY. MOISTURE LOOKS TO BE LACKING WITH THIS SYSTEM SO DECIDED
NOT TO MAKE ANY CHANGES TO POPS DURING THIS TIME FRAME.

19

&&

.AVIATION...12Z TAF DISCUSSION.

SCT TO OVC STRATO-CUMULUS CLOUDS AT AROUND 3 TO 4 KFT ARE EXPECTED
TO REMAIN AROUND THE AREA THROUGH A GOOD PORTION OF THE MORNING
HOURS POSSIBLY LASTING INTO THE AFTERNOON.  THIS WILL MAINLY EFFECT
THE NORTHERN SITES EET...BHM...ANB...AND POSSIBLY TCL...WHILE SOUTH
AT MGM AND TOI THE SKIES ARE EXPECTED TO REMAIN MOSTLY CLEAR.  THE
ONLY OTHER AVIATION CONCERN WILL BE THE GUSTY NORTHWEST WINDS.
WINDS WILL LIKELY BE ANYWHERE FROM 10 TO 20 KNOTS...WITH SOME GUSTS
FROM 25 TO AT A PEAK 30 KNOTS.  WINDS SHOULD SUBSIDE SOMEWHAT AS WE
GO INTO THE EVENING AND OVERNIGHT HOURS.

REMINDER NOTE: WILL CONTINUE TO INCLUDE THE LINE (AMD LTD TO VIS
WIND AND WX) FOR KEET DUE TO CONTINUED CONCERN OVER THE CEILOMETER.
THE CEILOMETER WILL BE IN TESTING PHASE THROUGH FEBRUARY.

&&

.BMX WATCHES/WARNINGS/ADVISORIES...A WIND ADVISORY IS IN EFFECT FROM
9AM THROUGH 5PM WEDNESDAY FOR AREAS GENERALLY ALONG AND EAST OF A
LINE FROM VERNON TO CLANTON TO TROY.

&&

$$

19/17