Special Weather Statement, NWS Atlanta, GA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
317 PM EDT TUE AUG 14 2012

.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...

RADARS SHOW SCATTERED TSTMS DEVELOPING IN EAST AL AND SOUTHWEST
GA AT THIS TIME. DIURNAL HEATING...COMBINED WITH CAPES IN THE 2000
TO 4000 RANGE AND PWS AROUND 1.7 INCHES IN ADVANCE OF THE
APPROACHING COLD FRONT...WILL PROMOTE FURTHER TSTM DEVELOPMENT
THIS AFTERNOON INTO EARLY EVENING. EXPECT MOST OF THE ACTIVITY TO
DIMINISH AROUND SUNSET. GFS/NAM MODELS SHOW A VIGOROUS SHORT WAVE
IN THE BASE OF AN UPPER LEVEL TROUGH OVER THE MIDDLE MS RIVER VALLEY
SWEEPING THROUGH THE TN VALLEY BY WEDNESDAY MORNING. EVEN THOUGH
DRIER AIR WILL BEGIN TO FLOW INTO GA BEHIND THE COLD FRONT TONIGHT...
THE SHORT WAVE SHOULD HAVE ENOUGH UPPER LEVEL DYNAMICS TO CAUSE
ISOLATED SHOWERS OR TSTMS OVER NORTH GA EARLY WEDNESDAY MORNING.
OTHERWISE...DRIER AIR WILL CONTINUE TO FLOW INTO THE STATE ON
WEDNESDAY WITH FAIR SKIES AND A BREEZY NORTHWEST WIND. FAIR SKIES
EXPECTED ON WEDNESDAY NIGHT AS WEAK HIGH PRESSURE BUILDS OVER THE
STATE. TEMPERATURES WILL REMAIN A COUPLE OF DEGREES EITHER SIDE OF
NORMAL. USED A MAV/MET BLEND FOR TEMPS AND LEANED TOWARD THE MET FOR
POPS.

16

.LONG TERM /THURSDAY THROUGH TUESDAY/...

FRONTAL CLEARANCE THROUGH THE CWA WILL BE THE BIG TIMING STORY
COME THE END OF THE LONG TERM. CURRENT EXTENDED GUIDANCE SUGGESTS
AN EXIT IN THE TIME FRAME BEYOND THE FORECAST PERIOD. MADE NO
MAJOR CHANGES TO THE LONG TERM FORECAST ISSUED ON THE MIDNIGHT
SHIFT...SEE THE PREVIOUS DISCUSSION PASTED BELOW FOR MORE.

RAG

/ISSUED AT 324 AM EDT TUE AUG 14 2012/
EASTERN U.S. REMAINS UNDER THE INFLUENCE OF THE LONG WAVE UPPER
TROUGH THROUGH THE EXTENDED FORECAST PERIOD. TROUGH STARTS OUT
RATHER FLAT AT MIDWEEK BEHIND AN EXITING SHORT WAVE...BUT SHARPENS UP
AND DEEPENS AS WE APPROACH THE WEEKEND. SHOULD SEE ANOTHER MOSTLY DRY
AND MILD BREAK WEDNESDAY NIGHT AND THURSDAY WITH PRECIPITATION
CHANCES INCREASING ONCE AGAIN AS WE HEAD INTO THE UPCOMING WEEKEND.
DEEP UPPER TROUGH DRIVES ANOTHER FAIRLY STOUT COLD FRONT INTO THE
STATE FOR THE WEEKEND. HARD TO TIME THE BEST PERIODS FOR
PRECIPITATION THROUGH THE WEEKEND AS THE FRONT LINGERS AND SHORT
WAVES ROTATE THROUGH THE LONG WAVE TROUGH SO I HAVE KEPT POPS IN THE
CHANCE RANGE FRIDAY THROUGH SUNDAY. SHOULD START TO SEE A BIT OF
BREAK BY MONDAY AS THE FRONT SINKS SOUTH ALLOWING DRIER AIR TO FILTER
IN AND THE UPPER TROUGH AXIS SHIFTS EAST OF THE STATE.

20

&&

.PREV DISCUSSION...

AVIATION...
18Z UPDATE.../ISSUED 147 PM EDT TUE AUG 14 2012/
VISIBLE SATELLITE LOOP SHOWS A BREAK IN THE CLOUDS OVER ATL WITH
SCATTERED TO BROKEN LOW AND MID CLOUDS OVER THE REMAINDER OF THE
TAF SITES. MORNING MODEL RUNS STILL SHOW ENOUGH MOISTURE AND
INSTABILITY AVAILABLE IN ADVANCE OF THE COLD FRONT TO COMBINE WITH
THE DIURNAL HEATING FOR TSTM DEVELOPMENT. BEST TIME PERIOD FOR
CONVECTION WILL BE 20-24Z. DEPENDING ON THE AMOUNT OF
RAINFALL...EXPECT CIGS TO LOWER TO IFR FROM 09-14Z AT MOST
LOCATIONS. DRIER AIR WILL MOVE IN WITH A NORTHWEST FLOW DURING THE
REMAINDER OF WEDNESDAY.

//ATL CONFIDENCE...18Z UPDATE...
MEDIUM ON ALL ELEMENTS.

16

&&

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          69  89  67  91 /  20  10   5  10
ATLANTA         71  89  70  90 /  20  10   5  10
BLAIRSVILLE     63  82  61  87 /  20  30  10  10
CARTERSVILLE    68  87  63  90 /  20  10  10  10
COLUMBUS        72  93  73  92 /  20   5   5  10
GAINESVILLE     70  88  67  89 /  20  20  10  10
MACON           72  92  71  92 /  10   5   5  10
ROME            68  87  63  91 /  20  20  10  10
PEACHTREE CITY  68  88  65  90 /  20   5   0  10
VIDALIA         73  93  73  92 /  10   5   5  10

&&

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

SHORT TERM...16
LONG TERM....RAG
AVIATION...16

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
400 AM EDT TUE AUG 14 2012

GAZ001>009-011>016-019>025-027-030>039-041>062-066>076-078>086-
089>098-102>113-151000-
BALDWIN-BANKS-BARROW-BARTOW-BIBB-BLECKLEY-BUTTS-CARROLL-CATOOSA-
CHATTAHOOCHEE-CHATTOOGA-CHEROKEE-CLARKE-CLAYTON-COBB-COWETA-
CRAWFORD-CRISP-DADE-DAWSON-DEKALB-DODGE-DOOLY-DOUGLAS-EMANUEL-
FANNIN-FAYETTE-FLOYD-FORSYTH-GILMER-GLASCOCK-GORDON-GREENE-
GWINNETT-HALL-HANCOCK-HARALSON-HARRIS-HEARD-HENRY-HOUSTON-JACKSON-
JASPER-JEFFERSON-JOHNSON-JONES-LAMAR-LAURENS-LUMPKIN-MACON-
MADISON-MARION-MERIWETHER-MONROE-MONTGOMERY-MORGAN-MURRAY-
MUSCOGEE-NEWTON-NORTH FULTON-OCONEE-OGLETHORPE-PAULDING-PEACH-
PICKENS-PIKE-POLK-PULASKI-PUTNAM-ROCKDALE-SCHLEY-SOUTH FULTON-
SPALDING-STEWART-SUMTER-TALBOT-TALIAFERRO-TAYLOR-TELFAIR-TOOMBS-
TOWNS-TREUTLEN-TROUP-TWIGGS-UNION-UPSON-WALKER-WALTON-WARREN-
WASHINGTON-WEBSTER-WHEELER-WHITE-WHITFIELD-WILCOX-WILKES-
WILKINSON-
400 AM EDT TUE AUG 14 2012

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH AND CENTRAL GEORGIA.

.DAY ONE...TODAY AND TONIGHT...
SCATTERED THUNDERSTORMS EXPECTED THROUGH TONIGHT.

.SYNOPSIS...
A COLD FRONT WILL MOVE INTO NORTH GEORGIA BY THIS AFTERNOON. THIS
COLD FRONT WILL SINK SLOWLY SOUTH THROUGH NORTH GEORGIA INTO CENTRAL
GEORGIA OVERNIGHT.

.PRIMARY HAZARDS...
THE PRIMARY HAZARDS WILL BE FREQUENT LIGHTNING...HEAVY RAIN...GUSTY
WINDS UP TO 45 MPH AND SMALL HAIL. THE BEST TIME FOR STORMS WILL BE
TODAY THROUGH TONIGHT ACROSS NORTH AND WEST CENTRAL GEORGIA...
SPREADING ACROSS THE REMAINDER OF CENTRAL GEORGIA THIS EVENING
THROUGH TONIGHT.

.DISCUSSION...
MOISTURE CONTINUES TO INCREASE AHEAD OF A COLD FRONT APPROACHING FROM
THE NORTHWEST. A WEAK SHORT WAVE WILL BRING THUNDERSTORMS INTO NORTH
AND WEST CENTRAL GEORGIA THIS MORNING...HOWEVER INSTABILITY REMAINS
LIMITED. BY THIS AFTERNOON THROUGH TONIGHT...THE COLD FRONT MOVES
INTO NORTHWEST GEORGIA AND SINKS SLOWLY SOUTHEAST INTO CENTRAL
GEORGIA AS ANOTHER WEAK TO MODERATE SHORT WAVE SWEEPS THROUGH THE
REGION. INSTABILITY REMAINS MODERATE AT BEST THROUGH THE PERIOD WITH
CAPE 1500 TO 2500 THIS AFTERNOON INTO THIS EVENING...KEEPING THE
CHANCES FOR SEVERE THUNDERSTORMS LIMITED.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY...
THERE IS A SLIGHT CHANCE OF THUNDERSTORMS WEDNESDAY AND MONDAY...WITH
A CHANCE OF THUNDERSTORMS FRIDAY THROUGH SUNDAY.

.SPOTTER INFORMATION STATEMENT...
SPOTTERS ACTIVATION IS NOT REQUESTED BUT SPOTTERS ARE ENCOURAGED TO
SUBMIT REPORTS OF SEVERE WEATHER THROUGH THE WEB BY GOING TO
WEATHER.GOV/ATLANTA.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
508 PM EDT TUE AUG 14 2012

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0450 PM     TSTM WND DMG     1 SW GRISWOLDVILLE      32.86N 83.51W
08/14/2012                   JONES              GA   AMATEUR RADIO

            AMATEUR RADIO OPERATOR RELAYED A REPORT OF SEVERAL TREES
            DOWN OVER EXTREME SOUTHEAST JONES COUNTY.

&&

DEESE

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
609 PM EDT TUE AUG 14 2012

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0505 PM     TSTM WND DMG     3 SE JEFFERSONVILLE     32.65N 83.30W
08/14/2012                   TWIGGS             GA   AMATEUR RADIO

            LARGE TREE FELL ON A HOUSE ON CHARLIE FLOYD RD.

&&

SNELSON

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
621 PM EDT TUE AUG 14 2012

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0600 PM     TSTM WND DMG     TENNILLE                32.94N 82.81W
08/14/2012                   WASHINGTON         GA   COUNTY OFFICIAL

            NUMEROUS TREES DOWN IN THE SANDERSVILLE AND TENILLE
            AREAS. AREAS SOUTH OF TENILLE ALSO AFFECTED.

&&

SNELSON

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
639 PM EDT TUE AUG 14 2012

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0625 PM     TSTM WND DMG     3 N BARTOW              32.92N 82.47W
08/14/2012                   JEFFERSON          GA   PUBLIC

            SEVERAL TREES DOWN AND MANY LARGE LIMBS DOWN...SOME
            BLOCKING U.S. HWY 221.

&&

SNELSON

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
644 PM EDT TUE AUG 14 2012

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0540 PM     TSTM WND DMG     5 E IRWINTON            32.81N 83.09W
08/14/2012                   WILKINSON          GA   AMATEUR RADIO

            NUMEROUS TREES AND POWER LINES DOWN.

&&

SNELSON

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
649 PM EDT TUE AUG 14 2012

GAZ074-076-085-086-142300-
649 PM EDT TUE AUG 14 2012

...SIGNIFICANT WEATHER ADVISORY FOR 50 MPH WINDS IN WASHINGTON...
JOHNSON...EMANUEL AND JEFFERSON COUNTIES UNTIL 700 PM EDT...

AT 644 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM OVER LOUISVILLE...MOVING NORTHEAST AT 30 MPH.

WIND GUSTS OF 50 MPH ARE LIKELY AS THESE STORMS MOVE ACROSS
WASHINGTON...JOHNSON...EMANUEL AND JEFFERSON COUNTIES THROUGH 700 PM
EDT. SOME LOCATIONS IN THE PATH OF THESE STORMS INCLUDE GRANGE...
STAPLETONS CROSSROADS...MOXLEY...WADLEY...BARTOW...DAVISBORO...
COLEMANS LAKE...LOUISVILLE...STELLAVILLE...MATTHEWS AND WRENS.

&&

LAT...LON 3308 8228 3293 8227 3284 8231 3281 8224
      3273 8258 3311 8266 3313 8263 3312 8258
      3315 8257 3328 8228 3325 8224 3322 8223
TIME...MOT...LOC 2248Z 241DEG 15KT 3299 8243