000
FXUS62 KFFC 201159
AFDFFC

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
745 AM EDT MON MAY 20 2013

.SHORT TERM /TODAY THROUGH TUESDAY NIGHT/...
THE IMMEDIATE SHORT TERM WILL BE SPENT DEALING WITH RESULTS OF A
NEARLY 24 HOUR LONG RAINFALL EVENT WHICH INCLUDES THE DEVELOPMENT
OF LOW CLOUDS AND FOG. GENESIS REGION FOR THIS IS THE CAROLINAS
AND OVER THE LAST SEVERAL HOURS HAS SPREAD WEST INTO THE NORTHEAST
MOUNTAINS AND JUST NOW ENTERING INTO THE REMAINDER OF NORTH
GEORGIA. NAM12 VERY BULLISH ON FOG DEVELOPMENT THROUGH THIS
MORNING WITH WIDESPREAD CONDENSATION PRESSURE DEFICIT VALUES RIGHT
AROUND ZERO. GFS NOT NEARLY THIS AGGRESSIVE BUT BASED ON
OBS...LOOKS LIKE NAM12 IS INITIALIZING BETTER AT THIS POINT AND
WILL FAVOR ITS SOLUTION.

FOG AND LOW CLOUDS TO SLOWLY LIFT DURING THE MORNING HOURS BUT
ENOUGH LOW LEVEL MOISTURE REMAINS TO MAINTAIN A CIG DECK FOR MUCH
OF THE DAY. AS FAR AS POPS AREA CONCERNED...MODELS IN AGREEMENT
THAT UPPER RIDGE AXIS WILL SHIFT EASTWARD...GETTING US OUT OF THE
BELT OF NW FLOW AND LIMITING EFFECTS FROM ANY IMPULSES TO OUR
EXTREME EASTERN SECTIONS. AM A LITTLE CONCERNED THAT WEAK SYNOPTIC
WINS WILL ALLOW SEA BREEZE AND DEVELOPING OUTFLOWS PROPAGATE WEST
AND BRING SHOWERS AND THUNDERSTORMS WITH THEM SO HAVE GONE ABOVE
GUIDANCE FORM MY SOUTHEAST ZONES TODAY. HRRR SHOWS SEPARATE
SECTION DEVELOPING DURING THE AFTERNOON. ALTHOUGH THIS REGION IS
CLOSER TO UPPER RIDGE...STRENGTH OF THIS FEATURE IS LIMITED AND
WILL NEED TO CARRY AT LEAST SLIGHT CHANCE POPS ALL ZONES.

LOW CLODS AND FOG NOT QUITE AS PROMINENT IN THE MODELS TUESDAY
MORNING BUT SATELLITE LOOKS LIKE DECENT DEVELOPMENT OVER THE EASTERN
THIRD OF THE REGION...ESPECIALLY THE NORTHEAST MOUNTAINS. THIS
WILL GIVE WAY ONCE AGAIN TO IMPROVING SKY CONDITIONS BY AFTERNOON
BUT POPS LOOK TO BE ON THE INCREASE AGAIN. UPPER RIDGE AXIS
WEAKENS SLIGHTLY IN RESPONSE TO APPROACHING TROUGH.
MEANWHILE...LOW LEVEL INSTABILITY AND LAPSE RATES WILL BE ON THE
INCREASE WITH CAPE VALUES OF NEAR 3000 J/KG PROJECTED LATE
TUESDAY. GIVEN FLOW PATTERN...WOULD EXPECT DEVELOPMENT OVER THE NE
MOUNTAINS FIRST AND THEN PROPAGATING SW TOWARD THE ATLANTA METRO.
HAVE GONE A CONSIDERABLE AMOUNT ABOVE GUIDANCE FOR THESE AREAS.

DEESE

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
UPPER LEVEL TROUGH APPROACHING ON WEDNESDAY AND COMBINED WITH
ASSOCIATED MOIST AND INSTABILITY WILL GIVE POTENTIAL FOR NUMEROUS
SHOWERS AND SCATTERED THUNDERSTORMS ACROSS MAINLY N GA AND MAINLY
SCATTERED SHOWERS AND STORMS FOR CENTRAL GA. A WEAK COLD FRONT GETS
INTO THE AREA LATE THURSDAY...POSSIBILITY ASSOCIATED WITH SOME UPPER
LEVEL SUPPORT...WILL GIVE THE CHANCE FOR SHOWERS AND STORMS. BEST
MOISTURE AND UPPER SUPPORT DRIFTING EAST ON FRIDAY ALLOWING FOR ONLY
A SLIGHT CHANCE OF SHOWERS AND STORMS. OVERALL MOISTURE AND
INSTABILITY APPEAR LACKING SATURDAY INTO MONDAY AND WHILE PRECIP
POTENTIAL IS NOT ZERO IT LOOKS TO BE LESS THAN 20 PERCENT AT THIS
TIME. TEMPERATURES RUNNING WITHIN 5 DEGREES OF NORMAL THROUGH THE
PERIOD.

BDL

&&

.AVIATION...12Z UPDATE...
IFR/LIFR THIS MORNING SHOULD PREVAIL AT THE TERMINAL SITES UNTIL AT
LEAST 14Z...WITH IMPROVEMENT TO VFR BY 17Z. WINDS ARE TRICKY WITH
LIGHT EASTERLY FLOW EXPECTED TO LAST MUCH OF THE MORNING THEN SWITCH
TO SOUTHWEST 5 TO 8 KT BY AFTERNOON. CONVECTION SHOULD REDEVELOP
THIS AFTERNOON BUT WILL BE WIDELY SCATTERED...SO HAVE NOT PUT IN THE
TAFS AT THIS TIME.

//ATL
CONFIDENCE...12Z UPDATE...
MEDIUM ON CIGS AND WINDS.
HIGH ON REMAINING ELEMENTS.

41

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          84  65  86  64 /  20   5  40  40
ATLANTA         85  68  86  67 /  20   5  30  30
BLAIRSVILLE     82  58  83  63 /  20   5  30  30
CARTERSVILLE    86  65  87  66 /  20   5  20  20
COLUMBUS        88  67  89  67 /  20  10  20  20
GAINESVILLE     83  65  85  66 /  20   5  40  40
MACON           86  64  88  64 /  30   5  30  30
ROME            87  65  88  66 /  20   5  20  20
PEACHTREE CITY  86  62  87  63 /  20   5  30  30
VIDALIA         85  66  87  69 /  40  20  30  30

&&

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...DEESE
LONG TERM....BDL
AVIATION...DEESE