Area Forecast Discussion
Issued by NWS Atlanta, GA

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS62 KFFC 050521 AAC
AFDFFC

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
121 AM EDT WED AUG 5 2015



.PREV DISCUSSION...

UPDATE...
/ISSUED 916 PM EDT TUE AUG 4 2015/
NO SIGNIFICANT CHANGES TO THE FORECAST. FORECAST LOW TEMPERATURES
RUNNING ABOUT 3 DEGREES ABOVE NORMAL.


SHORT TERM /TONIGHT THROUGH THURSDAY/...
/ISSUED 318 PM EDT TUE AUG 4 2015/
UPPER RIDGE ALREADY ESSENTIALLY GONE...HOWEVER LIMITED MOISTURE
CONTINUES TO LIMIT DIURNAL CONVECTION THIS AFTERNOON. DEEPER
MOISTURE SHOULD SPREAD OVER THE REGION TOMORROW WITH BETTER...
ALTHOUGH STILL SCATTERED...CONVECTIVE COVERAGE EXPECTED WEDNESDAY
AFTERNOON. SHORT WAVE APPROACHING OVERNIGHT WEDNESDAY NIGHT...BUT
BETTER CHANCES FOR PRECIPITATION SHOULD HOLD OFF UNTIL THE DAYTIME
THURSDAY. ANOTHER NIGHT WITH TEMPERATURES AT OR SLIGHTLY BELOW
SEASONAL NORMALS ACROSS THE NORTHERN HALF OF THE FORECAST AREA
TONIGHT...AND ANOTHER DAY WITH TEMPERATURES AT OR A BIT ABOVE
NORMAL TOMORROW. WE SHOULD SEE AT LEAST SOME SLIGHT MODERATION OF
TEMPERATURES TOMORROW AFTERNOON AS AT LEAST MARGINALLY BETTER
CLOUD COVER IS EXPECTED.

20

LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
/ISSUED 318 PM EDT TUE AUG 4 2015/
MODELS CONTINUE TO SHOW IMPULSE IN UPPER LEVEL FLOW AS TROUGH
DIGS INTO THE SOUTHEAST ON THURSDAY. HAVE BACKED OFF ON HOW FAR
SOUTH LIKELY POPS WILL EXTEND INITIALLY THURSDAY MORNING...BASED
UPON ECMWF/GFS KEEPING SHORTWAVE NORTHWEST OF THE AREA UNTIL
THURSDAY AFTERNOON AND EVENING. OTHERWISE NO MAJOR CHANGES MADE.

ATWELL

PREVIOUS DISCUSSION.../ISSUED 308 AM EDT TUE AUG 4 2015/
LONG TERM PORTION BEGINS AS A TRANSITIONAL PERIOD WITH LARGELY
ZONAL FLOW LATE WEDNESDAY BECOMING A LARGE SCALE TROUGH BY
THURSDAY AFTERNOON. SOME DIFFERENCES BEGINNING TO EMERGE WRT THE
EVOLUTION OF THIS FEATURE WITH GFS NOW SHOWING LESS AMPLITUDE WITH
THE TROUGH THAN ITS ECMWF COUNTERPART. REGARDLESS...BOTH APPEAR
STRONG ENOUGH TO ALLOW FOR LARGE SCALE LIFT OVER THE AREA AND WHEN
COMBINED WITH PRECIPITABLE WATER VALUES OVER 2 INCHES SHOULD
RESULT IN REALLY GOOD COVERAGE OF STORMS.

SHEAR VALUES CONTINUE TO BE MARGINAL FOR THIS SYSTEM BUT
ORGANIZATION ALONG ACTUAL SURFACE TROUGH APPEARS LIKELY AND WOULD
AID IN THE DEVELOPMENT OF A LINEAR TYPE CONVECTIVE COMPLEX WITH
DAMAGING WINDS THE MAIN CONCERN. HAVE CONTINUED THE MENTION OF
LIKELY POPS AND INCREASED COVERAGE TO INCLUDE THE ATLANTA METRO
ALTHOUGH THIS MAY BE AFTER 00Z ON FRIDAY.

SURFACE TROUGH REMAINS OVER THE AREA ON FRIDAY AS UPPER LEVELS
TRANSITION QUICKLY TO NW FLOW ALOFT REGIME. THERE LOOKS TO BE SOME
POTENT SHORTWAVE ACTIVITY WITHIN THIS TROUGH AND WOULD EXPECT GOOD
COVERAGE OF STORM AGAIN ON FRIDAY. ANOTHER SHORTWAVE PUSHING
THROUGH THE MID ATLANTIC ON SATURDAY SHOULD ALLOW FOR MOST AREAS
TO DRY OUT ALTHOUGH WILL NEED TO CONTINUE TO MONITOR FOR
SHORTWAVES CLIPPING THE NE CORRIDOR.

RIDGE TRIES TO BUILD BACK IN FOR EARLY NEXT WEEK WITH A RETURN TO
MID TO UPPER 90S. LATEST MEX IS ACTUALLY MUCH WARMER WITH 100S FOR
A LARGE PORTION OF THE AREA BUT WOULD LIKE TO SEE ANOTHER RUN
BEFORE COMMITTING TO THESE VALUES.

DEESE

&&

.AVIATION...
06Z UPDATE...
VARIABLE WINDS AT ATL THIS MORNING SHOULD BECOME MORE
PREDOMINATELY ON THE WEST SIDE BY SUNRISE AND THEN REMAIN ON THE
WEST SIDE THROUGH THE TAF PERIOD. THERE IS A CHANCE OF
THUNDERSTORMS AT ALL THE TAF SITES GENERALLY AFTER 19Z THIS
AFTERNOON SO HAVE INCLUDED A PROB30. MAY SEE BRIEF MORNING FOG
THIS MORNING BUT SHOULD BE LIMITED TO MCN.

//ATL CONFIDENCE...06Z UPDATE...
HIGH CONFIDENCE ON CIGS AND VSBYS. MEDIUM CONFIDENCE ON WIND.

11

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          94  72  91  72 /  30  30  40  50
ATLANTA         93  72  90  74 /  30  30  50  50
BLAIRSVILLE     87  68  84  66 /  40  30  60  60
CARTERSVILLE    93  72  88  71 /  30  30  60  50
COLUMBUS        96  74  92  74 /  30  30  50  50
GAINESVILLE     92  72  88  72 /  40  30  50  50
MACON           95  73  92  73 /  30  30  40  40
ROME            92  71  89  71 /  30  30  60  60
PEACHTREE CITY  94  72  91  72 /  30  30  40  50
VIDALIA         96  75  93  74 /  30  20  40  50

&&

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

$$

SHORT TERM...11
LONG TERM....DEESE
AVIATION...11


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.