Flash Flooding and Flood in Georgia, March 5 to 6, 2003

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
258 PM EST WED MAR 5 2003

.OVERVIEW...UPPER TROUGH IN SOUTHWEST U.S. AND FAST WEST TO
SOUTHWEST UPPER FLOW WILL PERSIST THROUGH WEEKS END. FLOW WILL
FINALLY BEGIN TO BECOME WEST TO NORTHWEST  OVER THE WEEKEND INTO
EARLY NEXT WEEK AS SIGNS OF PATTERN CHANGE ARE IN SITE. MODELS HAVE
BEEN VERY INCONSISTENT IN THIS FAST FLOW AND WILL ADJUST MODELS
BASED ON CLIMO.

.SHORT TERM...ETA/NGM/AVN ARE IN GOOD AGREEMENT ON WEATHER NEXT 24
HOURS THEN DIVERGE BY FRIDAY. CURRENT SURFACE ANALYSIS HAS A
DEVELOPING DEWPOINT BOUNDARY ACROSS SOUTH GA. THIS BOUNDARY WILL
LIFT NORTH BETWEEN 00Z AND 06Z TO NEAR AN ATL/AHN LINE AND THEN HOLD
THERE OVERNIGHT. AT THE SAME TIME...DISTURBANCE OVER LA/TX WILL RACE
NORTHEAST OVERNIGHT. PE VALUES RISE TO 1.2 TO 1.5 INCHES. ALONG AND
JUST SOUTH OF THIS BOUNDARY IS MAIN CONCERN. SURFACE DEWPOINTS WILL
BE IN THE 50S NORTH OF THIS BOUNDARY AND AROUND 60 SOUTH OF THIS
BOUNDARY TONIGHT. AS DISTURBANCE SWEEPS THRU...ISOLATED SEVERE ARE
POSSIBLE...ESPECIALLY ALONG AND SOUTH OF I-20. LOW LEVEL JET WILL
INCREASE TO 40-50 KTS AND WILL COUPLE WITH RIGHT REAR UPPER JET OF
AROUND 150+ KTS. IN ADDITION...CAPES ARE FORECAST TO BE FROM 400 TO
1000...WHILE ENERGY HELICITY INDEX SHOULD RANGE FROM 0 TO 1 AND
CONVECTION STORM COMPOSITE WILL RANGE FROM 0.3 TO 0.8. LI VALUES
JUST SOUTH OF THIS BOUNDARY WILL BE 0 TO -2 WITH SHOWALTER VALUES OF
0 TO -2. WHAT DOES THIS ALL MEAN...INSTABILITY IS WEAK...BUT DECENT
SPEED AND SOME DIRECTIONAL SHEAR SUPPORTS ISOLATED SEVERE ALONG AND
JUST SOUTH OF BOUNDARY...MOST LIKELY FROM 03Z TO 09Z. WILL WORD
ZONES WITH WITH SOME SEVERE AS SPC HAS US OUTLOOKED IN SLIGHT RISK.
EXPECT WIND GUSTS AND LIGHTNING TO BE MAIN THREAT. WILL USE SFC
DEWPOINTS TO FORECAST MINS.

WEAK COLD FRONT WILL SWEEP ACROSS CWA THUR MORNING...ALLOWING
SHOWERS TO DIMINISH DURING THE DAY FROM NW TO SE. WILL USE BLEND OF
CLIMO AND LOCAL TEMP TECHNIQUES FOR HIGHS BASED ON FRONT PASSING
THRU. SHOWERS WILL LIKELY LINGER IN SOUTHERN CWA AND FRONT BEGINS TO
HOLD UP BY LATE AFTERNOON UNTIL NEXT WAVE ARRIVES FRIDAY.

FOR THURSDAY NIGHT...WILL KEEP RAIN GOING IN MIDDLE GEORGIA WHILE
WILL ALLOW FOR SOME CLEARING IN NORTH GEORGIA.

FOR FRI...WILL KEEP RAIN GOING IN MIDDLE GEORGIA WHILE WILL LET THE
NORTH BE MAINLY DRY. THANKS FOR TLH FOR COORDINATION ON RAINFALL
POTENTIAL. PREFER 48 HOUR TOTALS OF 0.25 TO 0.75 INCHES IN THE NORTH
BUT 1 TO 2 INCHES DOWNSTATE IN MIDDLE GEORGIA. WILL PASS ONTO NEXT
SHIFT TO MONITOR MIDDLE GA FOR POSSIBLE FLOOD WATCH LATER THU INTO
FRI.

AS WINDS COME AROUND TO NORTHEAST FRIDAY...WILL NEED TO GO CLOSER TO
AVN MOS. WEAK WEDGING WILL KEEP TEMPS IN CHECK AND CLIMO SUPPORTS
THIS. MOS HAS IN GENERAL BEEN TO WARM LATELY AND PREFER CLIMO TO
SLIGHTLY ABOVE CLIMO NEXT 4 TO 7 DAYS.

.EXTENDED...WILL GO DRY SAT THRU TUE. HOWEVER...STILL A LITTLE
CONCERNED ABOUT LEFT OVER SOUTHWEST U.S. ENERGY. THIS WILL SPELL
LOTS OF CLOUDS AND A LITTLE SUN FOR THE WEEKEND...BUT WILL KEEP ALL
PRECIP SOUTH OF OUR CWA. TEMPS WILL BE CLIMO TO +5 OF CLIMO FOR
MAXES.

.PRELIMINARY POINT TEMPS/POPS...

KATL 56 63 48 61 / 99 40 10 20
KAHN 56 66 48 62 / 99 50 10 20
KGVL 53 64 44 60 / 99 40 10 10
KRMG 54 62 42 65 / 99 20 10 10
KCSG 62 69 54 65 / 90 60 50 50
KMCN 61 69 50 63 / 90 60 50 50

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

 NOEL

GAZ001>009-011>016-019>025-027-030>039-041>062-066>076-078>086-
089>098-102>113-060100-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
605 PM EST WED MAR 5 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH AND CENTRAL GEORGIA.

.DAY ONE...TODAY.
ISOLATED SEVERE THUNDERSTORMS EXPECTED ACROSS NORTH AND CENTRAL
GEORGIA THIS EVENING INTO EARLY THURSDAY.

.SYNOPSIS...
A COLD FRONT WILL MOVE INTO NORTH GEORGIA FROM THE NORTHWEST BY
THURSDAY MORNING. A SERIES OF WAVES WILL MOVE ACROSS THE STATE IN
SOUTHWESTERLY FLOW ALOFT.

.PRIMARY HAZARD...
THE PRIMARY HAZARDS FROM THE THUNDERSTORMS THIS EVENING AND TONIGHT
WILL BE LIGHTNING AND DAMAGING WINDS. THERE ALSO COULD BE ISOLATED
TORNADOES.

.DISCUSSION...
A TORNADO WATCH HAS BEEN ISSUED FOR MUCH OF ALABAMA VALID UNTIL
MIDNIGHT. THESE STORMS WILL BE MOVING INTO GEORGIA THIS EVENING. A
WATCH COULD BE ISSUED FOR PORTIONS OF GEORGIA AS EARLY AS 8 PM TO 9
PM. THE STORMS WILL BE MOVING THROUGH NORTH AND CENTRAL GEORGIA AT
MORE THAN 50 MPH. THIS COULD LEAD TO STRONG DAMAGING WINDS.

.FOR SPOTTERS...
SPOTTER GROUPS AND EMERGENCY MANAGEMENT PERSONNEL SHOULD MONITOR
LOCAL WEATHER CONDITIONS AND BE READY FOR POSSIBLE ACTIVATION THIS
EVENING.

.DAY TWO THROUGH DAY SEVEN...THURSDAY THROUGH TUESDAY.
THUNDERSTORMS ARE EXPECTED ACROSS CENTRAL GEORGIA THURSDAY
MORNING...OTHERWISE NO HAZARDOUS WEATHER EXPECTED THROUGH TUESDAY.

NO HAZARDOUS WEATHER EXPECTED AT THIS TIME.
FOR THE GRAPHICAL HAZARDOUS WEATHER OUTLOOK AND OTHER WEATHER
INFORMATION...PLEASE VISIT OUR WEBSITE AT WWW.SRH.NOAA.GOV/FFC.

GAZ021-022-032-033-060300-

SIGNIFICANT WEATHER ALERT
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
914 PM EST WED MAR 5 2003

...SIGNIFICANT WEATHER ALERT FOR FREQUENT LIGHTNING AND HEAVY
RAINFALL IN CHEROKEE...COBB...FORSYTH...AND NORTH FULTON COUNTIES.

THE NATIONAL WEATHER SERVICE DOPPLER RADAR DETECTED AN AREA OF STRONG
THUNDERSTORMS OVER CHEROKEE...COBB...FORSYTH...AND NORTH FULTON
COUNTIES. THE PRIMARY THREAT FROM THESE THUNDERSTORMS WILL BE
TORRENTIAL RAINFALL AND FREQUENT LIGHTNING. RAINFALL AMOUNTS OF 1 TO
2 INCHES CAN BE EXPECTED DURING THE NEXT HOUR. MOTORISTS OF THIS
AREA SHOULD SLOW DOWN OR AVOID TRAVEL DURING THE NEXT HOUR...AND
MONITOR NOAA WEATHER RADIO OR OTHER MEDIA OUTLETS FOR POSSIBLE
WARNINGS.

THIS ACTIVITY SHOULD GRADUALLY WEAKEN ACROSS THE AREA THROUGH 10
PM EST.

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.

JCD

GAZ023-034-060330-

SIGNIFICANT WEATHER ALERT
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
930 PM EST WED MAR 5 2003

...SIGNIFICANT WEATHER ALERT FOR HEAVY RAINFALL AND FREQUENT
CLOUD-TO-GROUND LIGHTNING IN GWINNETT AND HALL COUNTIES.

THE NATIONAL WEATHER SERVICE DOPPLER RADAR DETECTED AN AREA OF STRONG
THUNDERSTORMS OVER GWINNETT AND HALL COUNTIES. THE PRIMARY THREAT
FROM THESE THUNDERSTORMS WILL BE TORRENTIAL RAINFALL WITH FREQUENT
CLOUD-TO-GROUND LIGHTNING. RAINFALL AMOUNTS OF 1 TO 2 INCHES CAN BE
EXPECTED DURING THE NEXT HOUR. MOTORISTS OF THIS AREA SHOULD SLOW
DOWN OR AVOID TRAVEL DURING THE NEXT HOUR...AND MONITOR NOAA WEATHER
RADIO OR OTHER MEDIA OUTLETS FOR POSSIBLE WARNINGS.

THIS ACTIVITY SHOULD END ACROSS THE AREA BY 1030 PM EST.

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.

JCD

GAZ052-060330-

SIGNIFICANT WEATHER ALERT
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
941 PM EST WED MAR 5 2003

...SIGNIFICANT WEATHER ALERT FOR 45 MPH WINDS IN HEARD COUNTY.

THE NATIONAL WEATHER SERVICE DOPPLER RADAR DETECTED A LINE OF STRONG
THUNDERSTORMS ENTERING WESTERN HEARD COUNTY. THE PRIMARY THREAT FROM
THESE THUNDERSTORMS WILL BE WIND GUSTS TO 45 MPH...WHICH MAY CAUSE
SOME SMALL TREE LIMBS TO BE BLOWN DOWN. RESIDENTS OF THIS AREA
SHOULD STAY INSIDE AND AWAY FROM WINDOWS...AND MONITOR NOAA WEATHER
RADIO OR OTHER MEDIA OUTLETS FOR POSSIBLE WARNINGS.

THIS ACTIVITY SHOULD END ACROSS THE AREA BY 1030 PM EST.

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.

JCD