963
FXUS62 KFFC 161449
AFDFFC
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
1049 AM EDT WED OCT 16 2013
.UPDATE...
HIGH PRESSURE RIDGE REMAINS ANCHORED ALONG THE SPINE OF THE
APPALACHIANS WHILE A COLD FRONT IS SITUATED JUST EAST OF THE
MISSISSIPPI RIVER. THIS FRONT WILL SLOWLY MOVE EAST THROUGH TONIGHT.
REGIONAL RADAR SHOWS SOME LIGHT SHOWERS MOVING INTO NORTHERN AL.
HAVE SLOWED THE POPS DOWN A BIT ACROSS NORTHERN GA TO AFTER 18Z.
HAVE UPDATED THE SKY GRIDS TO REFLECT CURRENT CONDITIONS. STILL
THINK THE MAX T GRIDS LOOK GOOD...BUT THE HOURLY TEMPS WERE OFF A
COUPLE OF DEGREES.
&&
.PREV DISCUSSION... /ISSUED 744 AM EDT WED OCT 16 2013/
PREV DISCUSSION... /ISSUED 405 AM EDT WED OCT 16 2013/
.WIDESPREAD LIGHT RAIN TO DEVELOP ACROSS NORTHERN TIER...
SHORT TERM /TODAY THROUGH THURSDAY/...
RIDGE AXIS THAT HAS BEEN IN CONTROL OF THE LOCAL AREA WEATHER THE
PAST FEW DAYS CONTINUES TO WEAKEN ACCORDING TO LATEST MSAS
ANALYSIS. ALTHOUGH NOT A STRONG...INFLUENCE STILL BEING FELT AS
LOW LEVELS ARE DRYING OUT WITHIN RIDGE AXIS FROM THE PIEDMONT OF
THE CAROLINAS THROUGH MOST OF NORTH GEORGIA. THIS HAS PROVIDED FOR
NOTICEABLY LESS LOW CLOUD COVERAGE THIS MORNING ALTHOUGH INCREASED
CIRRUS CONTINUES TO KEEP NORTH GEORGIA MOSTLY CLOUDY. WITH
CLEARING SKIES TO THE SOUTH...TEMPERATURES ARE FALLING A LITTLE
FASTER THAN GUIDANCE AND HAVE ADJUSTED SHORT TERM TRENDS
ACCORDINGLY. OTHERWISE...JUST LIGHT RETURNS NOTED ON REGIONAL
RADAR OVER NORTH ALABAMA REQUIRING ONLY SLIGHT CHANCE POPS FOR THE
MORNING HOURS EXTREME NORTHWEST.
A BIT OF DIVERGENCE FROM THE ONSET TODAY AS NAM12 SHOWS FIRST
SIGNIFICANT PIECE OF SHORTWAVE ENERGY MOVING ACROSS NORTH GEORGIA
THIS MORNING WHILE THE GFS KEEPS IT LARGELY NORTH OF THE AREA OVER
TENNESSEE. AT THIS POINT FAVOR THE GFS GIVEN LACK OF SIGNIFICANT
RAIN THUS FAR OVER THE TENNESSEE VALLEY AND MORE IMPORTANTLY
NORTHERN ALABAMA. FOLLOWING THE GFS OUT THROUGH THIS EVENING THEN
SHOWS PRIMARY INITIAL LIFT IS DELAYED UNTIL LATE AFTERNOON OR
EARLY EVENING AND WILL THEREFORE NOT RAMP UP POPS UNTIL THIS
TIME FRAME. TRANSITION SHOULD BE A QUICK ONE HOWEVER AND WILL CARRY
LIKELY TO CATEGORICAL POPS WITH A SHARP GRADIENT THROUGH WEDNESDAY
NIGHT. INSTABILITY NOT AS GREAT WITH THIS RUN OF THE MODELS AND
SPC SREF THUNDER FORECAST CONFIRMS THIS. WILL LEAVE AS SHRA FOR
TODAY AND INTO TONIGHT.
MORE OF A GRAZING BLOW WITH SHORTWAVES SKIRTING ACROSS THE
NORTHERN TIER THROUGH THU BUT NOT MAKING ANY SIGNIFICANT PROGRESS
TO THE SOUTH. RESULTANT SENSIBLE WX SHOULD BE CATEGORICAL POPS
ACROSS THE NORTHERN TIER WITH A DECAYING LINE AS IT PROGRESSES
SOUTHWARD. WILL CARRY LIKELY FOR NORTH CENTRAL PORTIONS AND CHANCE
FOR THE SOUTH BEFORE MOVES THROUGH. ENOUGH INSTABILITY SNEAKS INTO
THE SOUTHERN SECTIONS BY THU AFTERNOON TO WARRANT ISOLATED THUNDER
IN THE GRIDS.
DEESE
LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
GFS/NAM SIMILAR WITH INDICATING THE COLD FRONT WILL EXIT THE
FORECAST AREA LATE THURSDAY NIGHT. BEST CHANCES FOR MEASURABLE
PRECIP LOOK TO BE OVER CENTRAL AND MAYBE SOME PORTIONS OF N GA.
FRIDAY LOOKS MOSTLY DRY WITH THE EXCEPTION BEING THE FAR SOUTHERN
PORTION OF THE FORECAST AREA WHERE LEFT OVER MOISTURE LINGERS IN
THE SW FLOW ALOFT. THE NAM IS THE MOST AGGRESSIVE WITH KEEPING
MOISTURE OVER CENTRAL GA AND THE GFS AND EUROPEAN LESS SO.
GFS AND EUROPEAN DIFFERING GREATLY FOR SATURDAY WITH THE EUROPEAN
MUCH WETTER MOVING A WEAK COLD FRONT TO THE AREA WITH A BETTER
ORGANIZED SHORT WAVE FORECAST AND MUCH MORE MOISTURE IN THE UPPER
FLOW. LEANED HARD ON WPC FORECAST POPS FAVORING THE WETTER EUROPEAN.
MOISTURE WILL BE EXITING THE AREA FOR SUNDAY WITH SMALL POPS FOR
PORTIONS OF CENTRAL GA. MOISTURE TRIES TO RETURN TO THE FAR SOUTHERN
FORECAST AREA ON MONDAY WITH ONLY SMALL POPS ASSOCIATED. GFS AND
EUROPEAN THEN GREATLY DIFFER MONDAY NIGHT AND TUESDAY WITH A MUCH
WETTER GFS RETURNING DEEP MOISTURE OVER THE ENTIRE AREA LIFTING A
WARM FRONT INTO CENTRAL GA. THE EUROPEAN IS MUCH DRIER WITH NO
PRECIP FORECAST. WPC TAKING A COMPROMISE WITH SMALL POPS MONDAY
NIGHT AND MAINLY CHANCE POPS FOR TUESDAY. THIS WILL NEED TO BE
CLOSELY MONITORED AS THE GFS IS PRODUCING HEAVY RAINFALL ACROSS N GA
ON TUESDAY ASSOCIATED WITH THE WARM FRONT WITH MUCH GREATER
INSTABILITY.
TEMPERATURES VARYING WITHIN 7 DEGREES OF NORMAL THROUGH THE EXTENDED
PERIOD.
BDL
AVIATION...
12Z UPDATE...
DRIER AIR INITIALLY FROM THE SURFACE TO AROUND 5K FT HAS FINALLY
GIVEN WAY TO SOME CIGS ACROSS THE TERMINALS ALTHOUGH MOST REMAIN
AT VFR AND ABOVE AT THIS HOUR. WILL KEEP A TEMPO FOR BKN030 IN FOR
THE MORNING HOURS FOR THE ATL TERMINALS. OTHERWISE...FOR THE
AFTERNOON...COULD SEE BKN CONDITIONS RE-EMERGE AS MOISTURE BEGINS
TO INCREASE ONCE AGAIN BUT CIGS SHOULD REMAIN VFR. HAVE BACKED OFF
ON -RA MOVING IN WITH DELAYED TIMING BUT STILL WILL NEED A PROB30
FOR LATE IN THE PERIOD...MAINLY AFT 06Z. PREDOMINANT -SHRA SHOULD
THEN TAKE GOLD AND PERSIST FOR THE REMAINDER OF THE TAF PERIOD.
//ATL CONFIDENCE...12Z UPDATE...
MEDIUM ON CIG REDEVELOPMENT AND WIND SHIFT TIMING.
HIGH ON REMAINING ELEMENTS.
DEESE
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 76 63 74 56 / 5 40 60 20
ATLANTA 76 64 72 55 / 10 40 60 10
BLAIRSVILLE 71 58 67 46 / 40 70 80 10
CARTERSVILLE 74 63 69 47 / 40 70 70 5
COLUMBUS 81 67 81 61 / 5 20 50 20
GAINESVILLE 74 63 70 53 / 20 50 60 10
MACON 80 60 83 61 / 5 20 40 20
ROME 73 64 70 45 / 50 80 80 5
PEACHTREE CITY 76 62 73 54 / 5 40 60 20
VIDALIA 82 62 84 65 / 5 10 20 20
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$