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000
FXUS62 KFFC 171131
AFDFFC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
731 AM EDT FRI MAY 17 2013



.PREV DISCUSSION... /ISSUED 346 AM EDT FRI MAY 17 2013/

SHORT TERM /TODAY THROUGH TONIGHT/...
HIGH PRESSURE REMAINS OFFSHORE THE SE COAST THIS MORNING. SOUTHERLY
FLOW CONTINUES TO BRING ABUNDANT MOISTURE NORTHWARD FROM THE GULF OF
MEXICO. REGIONAL RADAR SHOWS SOME VERY LIGHT SHOWERS OVER CENTRAL AL
THIS MORNING. SHOWERS LOOK TO HAVE DEVELOPED IN THE DIFFLUENT FLOW
JUST AHEAD OF A NEGATIVELY TILTED 500MB TROUGH. FOR THE LAST FEW
HOURS...THE SHOWERS HAVE STRUGGLED TO MAKE IT INTO FAR NE AL/NW GA.
DO THINK BY 12Z ISO/SCT LIGHT SHOWERS ARE POSSIBLE ACROSS THE NW
PORTION OF THE CWFA.

WORDING FOR CLOUDS TODAY WILL BE TRICKY. THE CIRRUS SHIELD WILL
CONTINUE TO OVERSPREAD THE CWFA THIS MORNING. DO THINK THAT THERE
WILL BE TIMES WHERE THE CIRRUS WILL BE SCT RATHER THAN BKN...BUT
OVERALL FILTERED SUNSHINE WILL BE THE RULE. IN ADDITION...DIURNALLY
DRIVEN CU IS EXPECTED TO DEVELOP DURING THE HEATING OF THE DAY.

NO MAJOR CHANGES TO THE POPS WERE NEEDED THROUGH THIS AFTERNOON.
STILL THINK THE BEST CHANCES FOR POPS REMAIN ACROSS NORTHERN GA...
BUT THE HIGHEST PERCENTAGES ARE STILL 40 OR LESS. THE FURTHER
SOUTH...POPS SHOULD REMAIN IN THE ISOLATED CATEGORY.

UPPER LOW AND ASSOCIATED SHORTWAVE APPROACH NW GA OVERNIGHT...AND
THE CHANCES FOR PRECIP WILL INCREASE AFTER 03-06Z. HAVE UPPED POPS
ACROSS THE NORTH OVERNIGHT TO LIKELY AFTER 06Z. HAVE KEPT THUNDER IN
THE FORECAST INTO THE OVERNIGHT AS THERE WILL BE SOME SURFACE
CAPE...BUT WILL KEEP THUNDER COVERAGE IN THE CHANCE CATEGORY FOR
NOW.

TOOK BLEND FOR TEMPS.

NLISTEMAA

LONG TERM /SATURDAY THROUGH THURSDAY/...
MODELS IN GENERAL AGREEMENT FOR SATURDAY TARGETING THE AREA WITH
SCATTERED TO NUMEROUS SHOWERS AND SCATTERED THUNDERSTORMS. THIS
DUE TO THE INFLUENCE OF UPPER LOW PRESSURE MOVING TO THE OH/TN
VALLEY AREAS AND THE MAIN UPPER TROUGH AFFECTING GA. WHILE N GA IS
TARGETED WITH THE HIGHEST POPS...INSTABILITY ACROSS THE AREA WILL
ALLOW FOR SCATTERED SHOWERS/STORMS ACROSS CENTRAL GA AS WELL. EVEN
WITH CLOUDS AND PRECIP CHANCES...A WARM AIRMASS IN PLACE WILL
ALLOW FOR HIGH TEMPERATURES NEAR NORMAL.

UPPER SYSTEM IN THE PROCESS OF PASSING THE AREA FOR SUNDAY BUT STILL
PLENTY OF MOISTURE AND INSTABILITY IN PLACE FOR SCATTERED TO
NUMEROUS SHOWERS AND SCATTERED THUNDERSTORMS. MODELS IN SOME
DISAGREEMENT FOR MONDAY WITH THE GFS WETTER THAN THE EUROPEAN AS THE
EUROPEAN HAS A STRONGER DRIER UPPER RIDGE MOVING OVER THE AREA THAN
THE GFS. GFS CONTINUES TO BE WETTER ON TUESDAY THAN THE EUROPEAN
WITH THE INFLUENCE OF AN UPPER RIDGE OVER THE AREA. STILL PLENTY OF
MOISTURE AND INSTABILITY FOR SOME AFTERNOON/EVENING CONVECTION.
INFLUENCE OF THE UPPER RIDGE DIMINISHES ON WEDNESDAY AS A COLD FRONT
MOVES ACROSS THE MID U.S. THIS WILL ALLOW FOR THE CHANCES OF SHOWERS
AND STORMS ACROSS THE AREA WITH CHANCES A LITTLE HIGHER ACROSS THE
N. GFS/EUROPEAN IN DISAGREEMENT WITH THE FRONT ON THURSDAY WITH THE
GFS MOVING THE FRONT INTO THE AREA AND THE EUROPEAN KEEPING THE
FRONT WELL TO THE NW. MOISTURE AND INSTABILITY WILL AGAIN COMBINE
FOR A CHANCE OF SHOWERS AND STORMS. A WEAK FRONT WILL LIKELY BE IN
THE AREA ON FRIDAY WITH AT LEAST SMALL CHANCES FOR SHOWERS AND
STORMS. TEMPERATURES GENERALLY RUNNING NEAR TO ABOVE NORMAL.

BDL

&&

.AVIATION...
12Z UPDATE...
CIRRUS WILL HANG AROUND THROUGH MOST OF TODAY...BUT THERE WILL BE
PERIODS WHERE THE UPPER CLOUDINESS WILL BE MORE SCT THAN BKN.
DIURNAL CU WILL DEVELOP WITH THE HEATING OF THE DAY...AROUND
040-050. MODELS/SOUNDINGS TAKE THE WIND DIRECTION A LITTLE EAST OF
SOUTH FRIDAY EVE. SPEEDS LESS THAN 5KT ARE FORECAST SO WILL KEEP
WINDS ON THE WEST SOUTH OF SOUTH AT THIS TIME. CONVECTION WILL
REMAIN N OF ATL THIS AFT. 6Z SOUNDINGS SHOW SOME LOW LEVEL
MOISTURE TOWARDS 12 SAT SO HAVE ADDED A SCT012 DECK.

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

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          85  62  83  64 /  20  20  60  60
ATLANTA         83  65  82  66 /  20  20  60  60
BLAIRSVILLE     77  60  74  58 /  30  60  70  60
CARTERSVILLE    81  62  81  63 /  30  50  70  60
COLUMBUS        85  65  86  67 /  20  10  50  40
GAINESVILLE     82  63  80  63 /  30  50  70  60
MACON           86  62  85  64 /  10  10  40  50
ROME            82  63  81  63 /  30  60  70  60
PEACHTREE CITY  83  61  81  64 /  20  20  50  60
VIDALIA         87  67  88  69 /  10  10  30  40

&&

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

$$

SHORT TERM...ATWELL
LONG TERM....ATWELL
AVIATION...ATWELL