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000
FXUS64 KBMX 122029
AFDBMX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BIRMINGHAM AL
229 PM CST THU DEC 12 2013

.SYNOPSIS...

SURFACE HIGH PRESSURE QUICKLY MOVES OFF TO THE EAST ON FRIDAY. THE
WELL ADVERTISED SOUTHERN STREAM STORM SYSTEM WILL TAKE SHAPE ACROSS
THE LOWER MISSISSIPPI VALLEY FRIDAY NIGHT AND MOVE OVER CENTRAL
ALABAMA THROUGH SATURDAY. THE HIGHEST RAIN CHANCES REMAIN FRIDAY
NIGHT THROUGH SATURDAY. RAIN AMOUNTS WILL AVERAGE FROM ONE HALF TO
ONE INCH WITH SOME ISOLATED HIGHER TOTALS. ANOTHER COLD FRONT MOVES
BY ON TUESDAY AND WILL BE DRY. THIS WILL REINFORCE THE COOL
CONDITIONS.

TEMPERATURES WILL GENERALLY REMAIN NEAR CLIMATOLOGY THROUGH THE
PERIOD...BUT SLIGHTLY FLUCTUATING FROM TIME TO TIME.

75

&&

.DISCUSSION...

THE HIGHLY ADVERTISED RAIN EVENT FRIDAY NIGHT AND SATURDAY STILL
LOOKS REASONABLE THIS PACKAGE. THE MODEL CONSENSUS HAS THE RAIN
ARRIVING A BIT LATER THAN ORIGINALLY FORECAST. LOOKING AT THE MODEL
OUTPUT SOUNDINGS...THE ATMOSPHERE REMAINS VERY DRY IN THE LOW TO
MID LEVELS WITH SATURATION IN THE 7-10K FT LEVEL OR HIGHER LATE
FRIDAY AFTERNOON INTO THE EARLY EVENING HOURS. THEREFORE...SLIGHTLY
LOWERED THE RAIN CHANCES AND MENTIONED SOME SPRINKLES. WOULD NOT BE
SURPRISED TO HEAR OF A FEW SLEET REPORTS...BUT THESE SHOULD BE VERY
LIMITED IN NATURE. THEREAFTER...WARM AIR SURGES IN ABOVE THE SURFACE
AND RAIN WILL FALL. THIS RAIN WILL SPREAD WEST TO EAST WITH ALL
AREAS RECEIVING RAIN THROUGH SATURDAY AFTERNOON. THERE DOES REMAIN
SOME ELEVATED INSTABILITY AND A FEW RUMBLES OF THUNDER MAY BE HEARD
FROM TIME TO TIME.

IT APPEARS THAT THE COLD AIR WILL NOT ARRIVE IN TIME FOR ANY
WINTRY PRECIP AT THE TAIL END OF THE RAIN...ACTUALLY THE TREND
APPEARS A BIT SLOWLY FOR THE COLDER AIR. IT ALSO APPEARS THAT MUCH
OF THE RAIN WILL BE OVER BY SUNDAY MORNING AND REMOVED MENTION.
WILL HAVE TO MONITOR THIS PERIOD AS THERE COULD BE SOME DRIZZLE
AROUND IN THE MORNING.

THE MODEL SOLUTIONS HAVE CHANGED OVER THE PAST FEW DAYS HANDLING
THE FORECAST NEXT WEEK. WENT CLOSER TO THE ECMWF ENSEMBLE AS THE
POSITIONS/AMPLITUDE OF THE SYNOPTIC RIDGES AND TROUGHS MAY LEAD TO
SOME DIFFERENCES IN THE FORTHCOMING REALITY. I THOUGHT WE WOULD BE
INFLUENCED BY A WARMING TREND...AND GENERALLY JUST BACKED THIS UP A
FEW DAYS AND HELD TEMPS CLOSER TO NORMAL. THE NEXT STORM SYSTEM TO
AFFECT THE AREA IS ALSO BACKED UP A FEW DAYS AND LOOKS LIKE NEXT
WEEKEND AT THE EARLIEST.

75

&&

.AVIATION...
18Z TAF DISCUSSION.

VFR CONDITIONS EXPECTED THRU THE PERIOD AS SFC HIGH PRESSURE
BUILDS IN FROM THE NW. LOOK FOR NORTHERLY WINDS AROUND 10 KTS TODAY
BECOMING LIGHT/CALM OVERNIGHT. COULD SEE A FEW CIRRUS STREAMING IN
FROM THE WEST THIS EVENING AND OVERNIGHT.

19


&&

.PRELIMINARY POINT TEMPS/POPS...
GADSDEN     22  50  39  55  39 /   0   0 100 100  20
ANNISTON    25  53  42  58  41 /   0   0  90 100  40
BIRMINGHAM  26  51  44  59  39 /   0  10 100 100  30
TUSCALOOSA  26  54  45  60  40 /   0  10 100 100  30
CALERA      27  55  44  61  40 /   0  10 100 100  40
AUBURN      27  54  45  61  45 /   0   0  50 100  80
MONTGOMERY  27  57  47  66  45 /   0   0  70 100  80
TROY        25  58  48  68  47 /   0   0  30 100  80

&&

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

&&

$$