Severe Thunderstorm Warning 411, NWS Atlanta, GA

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
530 PM EDT MON AUG 4 2003

254 PM PUBLIC FORECAST DISCUSSION...
.OVERVIEW...UPPER LEVEL PATTERN WILL CONTINUE TO AMPLIFY WITH RIDGE
IN THE ROCKIES AND TROUGH IN JUST WEST OF EAST COAST. THIS SPELLS
CONTINUE BELOW NORMAL TEMPS INTO THE WEEKEND WITH ABOVE NORMAL
RAINFALL. WHAT NEW...THIS IS THE SAME PATTERN AFFECTING THE AREA
LAST SEVERAL MONTHS.

THE ONE THING STICKING OUT ON THE HEMISPHERIC PATTERN IS BOCLKING
594+ RIDGE IN WESTERN EUROPE. SUMMER TELECONNECTIONS SUPPORT EASTERN
ATLANTIC TROUGH...WESTERN ATLANTIC RIDGE...EASTERN U.S. TROUGH...AND
WESTERN U.S. RIDGE. NO SIGNS OF THIS BREAKING IN NEXT 10+ DAYS.

.SHORT TERM...BEST 1000-850 MB MOISTURE CONVERGENCE HAS BEEN IN
MIDDLE GA TODAY...WHERE ORGANIZED CONVECTION IS. CLOUD COVER OVER N
GA...HAS KEPT INSTABILITY LIMITED TO THIS POINT. SHORTWAVE IS
PUSHING ACROSS CWA NEXT SEVERAL HOURS. LOW LEVEL MOISTURE FLUX
CONVERGENCE HAS INCREASED LAST FEW HOURS...SO EXPECT MORE ISOLATED
CONVECTION NEXT SEVERAL HOURS ACROSS CWA. MORE ORGANIZED CONVECTION
WILL REMAIN IN MIDDLE TO EAST CENTRAL GA AHEAD OF SHORTWAVE THRU 7
PM.

ANOTHER VORT LOBE/SPOKE CURRENTLY IN SOUTHERN IL WILL SWING
SOUTHEAST OVERNIGHT AND MAY BRING ANOTHER ROUND OF SCT ACTIVITY
MAINLY IN NW GA LATER TONIGHT AFTER 03-05Z. THEREFORE...WILL LEAVE
HIGHER POPS IN NW.

AS UPPER LEVEL TROUGH SHARPENS AND SHORTWAVES ROTATE THRU
TROUGH...RAIN CHANCES WILL REMAIN GREATEST THRU WED. THE MAIN
PROBLEM HAS BEEN TIMING AND DETAILS OF MESOSCALE PROCESSES. ETA HAS
COME MORE IN LINE WITH NGM AND GFS AND UKMET OVER EVOLUTION OF THE
DETAILS NEXT 2 TO 3 DAYS.

EXPECT A COMPLEX OF STORMS TO FORM TONIGHT TO OUR WEST AND PUSH
SOUTHEAST ALONG SFC DEWPOINT/THETA-E GRADIENT. THIS COULD AFFECT FAR
WESTERN GA LATER TONIGHT. EXPECT ANOTHER COMPLEX OF STORMS TO RIDE
SOUTHEAST IN GA LATE TUE INTO EARLY WED. ONLY DIFFERENCE IN MODELS
IS LOCATION. GFS MOVES THIS ACROSS ENTIRE CWA WHILE ETA SUGGESTS
SOUTHERN CWA. NGM IS IN BETWEEN. WITH UNCERTAINTY...PREFER ENTIRE
CWA SOLUTION OF GFS FOR NOW.

LI VALUES WILL DROP TO -2C TO -4C BY TUE AFTERNOON AND NIGHT...WHILE
PE AND PW VALUES RISE TO NEAR 2 INCHES ALONG WITH PRIME LOCATION OF
LEFT SIDE OF LOW-LEVEL THETA-E RIDGE. IN ADDITION...PE VALUES SHOULD
BE MAXIMIZED BY LOW LEVEL JET...NOSE OF EULERIAN MOISTURE
TRANSPORT...AND CONVECTION STORM INDEX VALUES OF 1.0 OR GREATER.
THUS...EXPECT MAIN THREAT OF WILL LOCALLY HEAVY RAIN LATER TUE INTO
EARLY WED.

AS FOR MAX TEMPS...GUIDANCE REMAINS TOO WARM...AND THICKNESS
TECHNIQUES CONTINUE TO SUPPORT TEMPS SEVERAL DEGREES BELOW
GUIDANCE...CLOSEST TO GFS MOS FOR MAXES.

WILL MAINTAIN CURRENT MIN TEMPS IN FORECAST.

.EXTENDED...UKMET/GFS/ECWMF IN GOOD AGREEMENT THAT TROUGHING WILL
REMAIN WITH US INTO THE WEEKEND...BUT WILL GRADUAL FILL AND WEAKEN.
THIS MEANS RAIN CHANCES WILL DECREASE AFTER WED INTO ISOLATED
CATEGORY. HOWEVER...WITH MEAN RH VALUES OF 60 TO 70 PERCENT...EXPECT
LOTS OF CLOUDS AND SOME SUN...WITH TEMPS BELOW GFS MOS GUIDANCE.
WILL TRIM UP TO 5 DEGREES FROM MOS FOR MAXES...CLOSE TO CURRENT
FORECAST.

MINS LOOK ON TRACK.

.PRELIMINARY POINT TEMPS/POPS...

KATL 70 83 70 82 / 20 40 60 50
KAHN 69 85 70 84 / 20 30 50 50
KGVL 68 84 69 82 / 20 30 50 50
KRMG 68 86 69 84 / 40 50 70 40
KCSG 72 89 72 87 / 20 40 40 50
KMCN 71 90 72 87 / 30 30 40 50

.ATL WATCHES/WARNINGS/ADVISORIES...
GA...NONE.

.AVIATION DISCUSSION...
SCATTERED CONVECTION ONGOING ACROSS AREA.  THIS SHOULD DISSIPATE
AFTER SUNSET.  HIGH RELATIVE HUMIDITY REMAINS BELOW 800MB. TONIGHT
SHOULD BE SIMILAR TO LAST NIGHT IN TERMS OF CEILINGS AND FOG...ALL
STATIONS SHOULD DROP TO IFR/MVFR BETWEEN 5-13Z. YET ANOTHER UPPER
DISTURBANCE APPROACHING FROM WEST WILL BRING TSRA TO ATL-CSG
VICINITY AROUND 18Z AND TO AHN-MCN AREA BY 20Z.

 NOEL/MOLLER/13

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
625 PM EDT MON AUG 4 2003

GAZ001>009-011>016-019>025-027-030>039-041>062-066>076-078>086-
089>098-102>113-050300-

625 PM EDT MON AUG 4 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH AND CENTRAL GEORGIA.

.DAY ONE...TONIGHT.

ISOLATED SEVERE THUNDERSTORMS POSSIBLE THIS EVENING.

.SYNOPSIS...
A WARM MOIST AIRMASS WILL PERSIST OVER NORTH AND CENTRAL GEORGIA
THROUGH TONIGHT AS A WEAK SURFACE BOUNDARY MEANDERS ACROSS THE AREA.
AN UPPER LEVEL DISTURBANCE IS EXPECTED TO SWEEP ACROSS THE TENNESSEE
VALLEY LATE TONIGHT.

.PRIMARY HAZARD...
ISOLATED SEVERE THUNDERSTORMS ARE POSSIBLE THIS EVENING...WITH THE
PRIMARY THREAT BEING LOCALLY HEAVY RAIN WHICH COULD PRODUCE
FLOODING. FREQUENT LIGHTNING...GUSTY WINDS AND SMALL HAIL WILL ALSO
BE POSSIBLE WITH THESE STORMS.

.DISCUSSION...
SCATTERED THUNDERSTORMS WILL CONTINUE OVER NORTH AND CENTRAL GEORGIA
THROUGH THE EVENING. WITH CAPES AROUND 2500 AND LIFTED INDICES IN
THE MINUS 2 TO MINUS 4 RANGE...SOME OF THE STORMS MAY BE SEVERE.
THE BEST CHANCE FOR THUNDERSTORMS THROUGH THE EVENING WILL BE NORTH
OF AN ATLANTA TO ATHENS LINE. WITH THE LOSS OF DAYTIME HEATING THE
THREAT OF THUNDERSTORMS WILL LESSEN AFTER MIDNIGHT.

.FOR SPOTTERS...
DUE TO THE ISOLATED NATURE OF THE SEVERE STORMS...SPOTTER ACTIVATION
IS NOT EXPECTED. HOWEVER...SPOTTER GROUPS AND EMERGENCY MANAGEMENT
PERSONNEL SHOULD CONTINUE TO MONITOR WEATHER CONDITIONS.

.DAY TWO THROUGH DAY SEVEN...TUESDAY THROUGH SUNDAY...

THERE WILL BE A CHANCE OF THUNDERSTORMS EACH DAY.

FOR THE GRAPHICAL HAZARDOUS WEATHER OUTLOOK AND OTHER WEATHER
INFORMATION...PLEASE VISIT OUR WEBSITE AT WEATHER.GOV...AND CLICK ON
GEORGIA.

GAZ093-095-104>106-041800-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
121 PM EDT MON AUG 4 2003

...SIGNIFICANT WEATHER ALERT FOR INTENSE LIGHTNING...AND BRIEF HEAVY
RAIN IN CRISP...SUMTER...MACON...HOUSTON AND DOOLY COUNTIES UNTIL
200 PM EDT...

THE BRIEF HEAVY RAIN MAY EXCEED TWO INCHES IN AN HOUR. THIS MAY
CAUSE SOME LOCALIZED FLOODING.

AT 118 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 8 MILES SOUTHWEST OF BYROMVILLE...MOVING EAST AT
35 MPH.

THIS ACTIVITY SHOULD BE ENDING OVER THE AREA BY 200 PM EDT.

SIGNIFICANT WEATHER ALERTS ARE ISSUED WHEN WINDS ARE EXPECTED TO
REACH 40 TO 50 MPH...HAIL IS EXPECTED TO BE LESS THAN THE SIZE OF
DIMES...OR SIGNIFICANT CLOUD-TO-GROUND LIGHTNING IS EXPECTED.

GAZ095-096-105-107-108-041845-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
156 PM EDT MON AUG 4 2003

...SIGNIFICANT WEATHER ALERT FOR GUSTY WINDS TO 35 MPH...INTENSE
LIGHTNING...AND HEAVY RAIN TO NEAR 2 INCHES IN AN HOUR IN
WILCOX...PULASKI...BLECKLEY...HOUSTON AND DOOLY COUNTIES UNTIL 245
PM EDT...

AT 154 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM OVER UNADILLA...MOVING EAST AT 25 MPH.

THIS ACTIVITY SHOULD BE ENDING OVER THE AREA BY 245 PM EDT.

SIGNIFICANT WEATHER ALERTS ARE ISSUED WHEN WINDS ARE EXPECTED TO
REACH 40 TO 50 MPH...HAIL IS EXPECTED TO BE LESS THAN THE SIZE OF
DIMES...OR SIGNIFICANT CLOUD-TO-GROUND LIGHTNING IS EXPECTED.

GAZ110>113-042045-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
402 PM EDT MON AUG 4 2003

...SIGNIFICANT WEATHER ALERT FOR HEAVY RAIN AND INTENSE LIGHTNING IN
TELFAIR...WHEELER...TOOMBS AND MONTGOMERY COUNTIES UNTIL 445 PM
EDT...

AT 357 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
LINE OF STRONG THUNDERSTORMS FROM AILEY TO 13 MILES SOUTH OF
SCOTLAND...MOVING SOUTHEAST AT 25 MPH.

THIS ACTIVITY SHOULD BE DIMINISHING OVER THE AREA BY 445 PM EDT.

SIGNIFICANT WEATHER ALERTS ARE ISSUED WHEN WINDS ARE EXPECTED TO
REACH 40 TO 50 MPH...HAIL IS EXPECTED TO BE LESS THAN THE SIZE OF
DIMES...OR SIGNIFICANT CLOUD-TO-GROUND LIGHTNING IS EXPECTED.

GAZ003-004-042230-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
558 PM EDT MON AUG 4 2003

...SIGNIFICANT WEATHER ALERT FOR SMALL HAIL AND GUSTY WINDS IN
WHITFIELD AND CATOOSA COUNTIES UNTIL 630 PM EDT...

AT 555 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM OVER COHUTTA...MOVING SOUTHEAST AT 10 MPH.

THIS ACTIVITY SHOULD BE ENDING OVER THE AREA BY 630 PM EDT.

SIGNIFICANT WEATHER ALERTS ARE ISSUED WHEN WINDS ARE EXPECTED TO
REACH 40 TO 50 MPH...HAIL IS EXPECTED TO BE LESS THAN THE SIZE OF
DIMES...OR SIGNIFICANT CLOUD-TO-GROUND LIGHTNING IS EXPECTED.