429 
FXUS62 KFFC 030221
AFDFFC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
1021 PM EDT SUN JUN 2 2013

.UPDATE...
SHOWERS AND THUNDERSTORMS HAVE LARGELY DISSIPATED ACROSS NORTH
GEORGIA...WITH THE REMAINING ACTIVITY ACROSS CENTRAL GEORGIA.
EXPECT THIS ACTIVITY TO CONTINUE THROUGH THE OVERNIGHT HOURS. HAVE
MADE MORE SUBSTANTIAL CHANGES TO THE POPS FOR THE OVERNIGHT
AND EARLY MORNING PERIODS TO REDUCE PRECIP CHANCES ACROSS THE
NORTHERN PORTIONS OF THE CWA...WHILE KEEPING THE CENTRAL GEORGIA
PORTIONS AS HIGH OR SLIGHTER HIGHER THAN THE PREVIOUS FORECAST. 

DIURNAL CONVECTION STILL EXPECTED MONDAY...AND HAVE ONLY MADE
MINOR CHANGES TO POPS AND WEATHER.

NO ADDITIONAL CHANGES ARE PLANNED AT THIS TIME.

31

&&

.PREV DISCUSSION... /ISSUED 801 PM EDT SUN JUN 2 2013/ 

.ISOLATED SEVERE STORMS POSSIBLE THIS EVENING...

SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
/ISSUED 405 PM EDT SUN JUN 2 2013/

COLD FRONT STILL NORTHWEST OF THE STATE HOWEVER TWO LINES OF 
CONVECTION HAVE DEVELOPED ACROSS THE CWA AHEAD OF THIS FRONT. LOCAL 
WRF HAS PICKED UP ON BOTH LINES BUT WEAKENS THE EASTERN LINE AND 
LETS THE WESTERN LINE DOMINATE. ALTHOUGH HRRR ISNT AS CLEAR WITH 
BOTH LINES...IT DOES SHOW THE WEST LINE OF CONVECTION CONTINUING TO 
DOMINATE AND PUSH EAST. FORECAST IS IN LINE WITH THESE TWO HI-RES 
MODELS WITH THE FOCUS BECOMING ON THE WEST LINE. WILL CONTINUE TO 
MOVE EAST TONIGHT SO HAVE SHOWN CATEGORICAL POPS INTO THE EVENING 
FOR MUCH OF THE CWA. WITH 1500-2000 J/KG OF MUCAPE THIS AFTERNOON 
ISOLATED SVR STORMS ARE POSSIBLE WITH THE MAIN THREATS BEING WIND 
AND HAIL. BEHIND THIS LINE...COULD STILL SEE SCATTERED STORMS 
DEVELOP OVERNIGHT. CONFIDENCE IS LOW THOUGH ON FORECAST TONIGHT AS 
THERE ARE SOME DIFFERENCES IN THE MODELS /INCLUDING HI RES/...SOME 
SHOWING AN ACTIVE NIGHT WHILE OTHERS LIMITING ACTIVITY. HAVE 
BASICALLY GONE CHANCE POPS THROUGH THE NIGHT. 

COLD FRONT WILL PUSH THROUGH NORTH GEORGIA TONIGHT AND INTO CENTRAL 
GEORGIA ON MONDAY. WILL BE ENOUGH MOISTURE AND LIFT FROM THE FRONT 
THAT CONVECTION IS POSSIBLE AGAIN ON MONDAY BUT THE BETTER CHANCES 
WILL BE ACROSS THE SOUTHEAST PART OF THE CWA. PLENTY OF INSTABILITY 
/2000 J/KG OF MUCAPE/ MONDAY AFTERNOON TO SEE A FEW STRONG STORMS. 

STORMS LOOK TO CONTINUE WITH LAST IN A SERIES OF SHORTWAVES TO
MOVE THROUGH MONDAY NIGHT. WILL INCREASE POPS TO HIGH END CHANCE
RANGE THROUGH 12Z TUESDAY AS FRONT PUSHES THROUGH.

TEMPS ARE NEAR A MODEL BLEND. 

11

PREV DISCUSSION... /ISSUED 207 PM EDT SUN JUN 2 2013/ 

PREV DISCUSSION...  

UPDATE...
/ISSUED 1025 AM EDT SUN JUN 2 2013/
SHOWERS AND THUNDERSTORMS HAVE BEEN SLOW TO DEVELOP ACROSS MUCH OF
THE CWA THIS MORNING SO MAIN CHANGE TO THE FORECAST HAS BEEN TO
REDUCE POPS FOR THE MORNING. BY EARLY AFTERNOON THOUGH...THE HRRR
INCREASES COVERAGE GREATLY ACROSS THE NORTH AND WESTERN PART OF
THE CWA AND THIS IS IN LINE WITH THE FORECAST. SOME INDICATION IN
THE MODELS SUCH AS THE GFS AND ECMWF THAT THE BETTER COVERAGE WILL
CONTINUE INTO TONIGHT AND MAY NEED TO ADJUST OUR POPS UPWARD
OVERNIGHT IN FUTURE UPDATES. 

PORTIONS OF FANNIN AND GILMER COUNTY HAVE ALREADY SEEN AROUND 4
INCHES OF RAIN DURING THIS EVENT SO FAR. ALTHOUGH THEY HAVE
RECEIVED A REPRIEVE FROM THE HEAVY RAIN...WILL HAVE TO CONTINUE TO
MONITOR THIS AREA CLOSELY FOR POTENTIAL ISOLATED FLOODING AS
HEAVY RAIN IS POSSIBLE AGAIN THIS AFTERNOON.

11

PREVIOUS LONG TERM...
TUESDAY THROUGH SATURDAY/... /ISSUED 353 AM EDT SUN JUN 2 2013/ MODELS
SHOW THE COLD FRONT PUSHING INTO SOUTH GA MONDAY NIGHT... WHERE IT
MEANDERS... THEN DRIFTS BACK NORTH SLIGHTLY BY TUESDAY AFTERNOON.
THIS WILL WARRANT HOLDING ONTO A SLIGHT CHANCE OF MAINLY AFTERNOON
AND EVENING THUNDERSTORMS ACROSS THE SOUTHERN REACHES OF THE
FORECAST AREA ON TUESDAY. A SLIGHT CHANCE OF STORMS SPREAD BACK
ACROSS NORTH GA BY WEDNESDAY AS AN EASTERLY WIND FLOW BEGINS TO
ADVECT DEEP ATLANTIC MOISTURE BACK OVER THE AREA WHILE A SERIES OF
UPPER DISTURBANCES BEGIN TO CARVE A BROAD LONG WAVE TROUGH THAT
STRETCHES DOWN THE MS VALLEY REGION BY WEDNESDAY AFTERNOON. THIS
UPPER TROUGH DEEPENS OVER THE SOUTH ON THURSDAY AND PROVIDES THE
SUPPORT FOR SCATTERED SHOWERS AND THUNDERSTORMS ACROSS THE ENTIRE
FORECAST AREA THURSDAY AFTERNOON AND EVENING. AT THE SAME TIME...
THE ECMWF AND GFS SHOW AN EARLY SEASON TROPICAL SYSTEM PUSHING
INTO THE EASTERN GULF ON THURSDAY... ACROSS CENTRAL FL AND INTO
THE WESTERN ATLANTIC ON FRIDAY...THEN UP THE EAST COAST ON
SATURDAY AS HIGH PRESSURE BUILDING SOUTH OF CANADA HELPS HOLD THE
SYSTEM OFF SHORE. AHEAD OF THIS SYSTEM ON FRIDAY... A CONTINUED
MOIST EASTERLY FLOW AND UPPER TROUGH WILL SUPPORT DIURNALLY DRIVEN
AFTERNOON AND EVENING CONVECTION ACROSS THE AREA AGAIN ON FRIDAY.
AS THE TROPICAL SYSTEM PUSHES OFF TO THE NE ON SATURDAY... MODELS
SHOW A COLD FRONT AND DRIER AIR SPREADING SOUTH IN ITS WAKE. DUE
TO MUCH UNCERTAINTY ON TIMING AND TRACK... WILL CONTINUE TO SHOW A
CHANCE OF CONVECTION ON SATURDAY FOR NOW AND MONITOR CHANGES IN
THE MODEL RUNS CLOSELY OVER THE NEXT SEVERAL DAYS.

39

AVIATION...
00Z UPDATE...
SHOWER AND THUNDERSTORM ACTIVITY STILL IMPACTING ATL AREA AND MCN
TAF SITES. ANTICIPATE ACTIVITY TO DIMINISH AFTER 02Z...WITH
LINGERING SHOWERS POSSIBLE THROUGH THE EARLY MORNING HOURS. CIGS
EXPECTED TO DEGRADE TO LOW MVFR BY 08-09Z...WITH SOME IMPROVEMENT
TO MID-HIGH MVFR BY 14-15Z. WINDS WILL BECOME W-WNW BEHIND THE
CONVECTION TONIGHT...WITH SPEEDS GENERALLY 6 KT OR LESS. WINDS
WILL INCREASE TO 6-8KT THROUGH MONDAY AFTERNOON. CONVECTION
EXPECTED AGAIN MONDAY GENERALLY AFTER 18Z...AND HAVE INCLUDED A
PROB30 -TSRA IN THE TAF FOR 19-23Z AT THIS TIME.

//ATL CONFIDENCE...00Z UPDATE...
MEDIUM CONFIDENCE ON MVFR CIGS AND VSBYS 08-14Z. 
HIGH CONFIDENCE ON ALL OTHER ELEMENTS.

31

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          67  84  63  87 /  60  50  30  10 
ATLANTA         69  84  68  86 /  80  30  10  10 
BLAIRSVILLE     62  80  60  81 /  50  40  10  10 
CARTERSVILLE    66  84  62  88 /  50  20  10  10 
COLUMBUS        72  87  70  89 /  40  40  30  10 
GAINESVILLE     67  83  65  85 /  90  40  20  10 
MACON           69  86  68  90 / 100  50  40  20 
ROME            67  83  61  88 /  40  20  10  10 
PEACHTREE CITY  67  84  62  87 /  80  30  20  10 
VIDALIA         72  86  71  89 /  70  60  40  30 

&&

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

$$

SHORT TERM...31
LONG TERM....17
AVIATION...31