Alert archive / Georgia / Flash Flood Warnings in 2014

Flash Flood Warning 17, NWS Atlanta, GA

July 11, 2014Forsyth County, Fulton County, Gwinnett County, Georgia

NWS Atlanta, GA issued this flash flood warning at Jul 11, 2014, 6:39 PM EDT for Forsyth County, Fulton County, Gwinnett County, Georgia. It was in force for 6 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jul 11, 2014, 6:39 PM EDT (22:39 UTC)
Expired
Jul 12, 2014, 12:30 AM EDT
In force
6 hr
Issued by
NWS Atlanta, GA
Area
Storm-based polygon
Flood severity
None

Counties Forsyth County, GA, Fulton County, GA, Gwinnett County, GA

The radar

The Atlanta radar (KFFC), 96 km from the middle of the area, began a volume at 22:40 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Peachtre/Fal Fld, GA (KFFC), launched 12:00Z, 10.7 hours before the alert went out and 92 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Peachtre/Fal Fld, GA at 12:00Z on 2014-07-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 710 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Peachtre/Fal Fld, GA at 12:00Z on 2014-07-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -3 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
710 J/kg
Mixed-layer CIN
-46 J/kg
Mixed-layer LCL
877 m above ground
0-6 km bulk shear
11 kt
0-1 km storm-relative helicity
-3 m²/s²
0-3 km storm-relative helicity
34 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

949 
WGUS52 KFFC 112239
FFWFFC
GAC117-121-135-120430-
/O.NEW.KFFC.FF.W.0017.140711T2239Z-140712T0430Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
639 PM EDT FRI JUL 11 2014

THE NATIONAL WEATHER SERVICE IN PEACHTREE CITY HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTHERN FORSYTH COUNTY IN NORTH CENTRAL GEORGIA
  NORTHEASTERN FULTON COUNTY IN NORTH CENTRAL GEORGIA
  NORTHERN GWINNETT COUNTY IN NORTH CENTRAL GEORGIA

* UNTIL 1230 AM EDT

* AT 630 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  POTENTIAL FLASH FLOODING OF CREEKS DUE TO NUMEROUS THUNDERSTORMS   
  WITH VERY HEAVY RAIN FROM ALPHARETTA THROUGH SUWANEE TO DACULA.    
  THE STORMS WERE NEARLY STATIONARY OVER THE WARNED AREA. RADAR      
  ESTIMATES OF 2 TO 3 INCHES OF RAIN HAVE OCCURRED OVER PORTIONS OF  
  THE WARNED AREA. ADDITIONAL RAINFALL OF ANOTHER INCH IS POSSIBLE   
  BEFORE THE STORMS GRADUALLY DISSIPATE BY 800 PM EDT.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO SUGAR   
HILL...REST HAVEN...BUFORD...MILTON AND CUMMING.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...URBAN AREAS...HIGHWAYS...STREETS AND UNDERPASSES
AS WELL AS OTHER DRAINAGE AREAS AND LOW LYING SPOTS.

IF YOU SEE SIGNIFICANT FLOODING CALL THE NATIONAL WEATHER SERVICE
TOLL FREE AT 1 8 6 6 7 6 3 4 4 6 6. YOU CAN ALSO TWEET YOUR REPORT
USING HASHTAG GAWX.

&&

LAT...LON 3421 8398 3419 8399 3419 8405 3416 8406
      3410 8388 3412 8382 3400 8387 3393 8380
      3406 8442 3410 8442 3413 8436 3417 8436
      3419 8433 3419 8426 3424 8425

$$


16
2 follow-up statements
953 
WGUS72 KFFC 120043
FFSFFC

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
843 PM EDT FRI JUL 11 2014

GAC117-121-135-120430-
/O.CON.KFFC.FF.W.0017.000000T0000Z-140712T0430Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
FORSYTH GA-GWINNETT GA-FULTON GA-
843 PM EDT FRI JUL 11 2014

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1230 AM EDT FOR
NORTHEASTERN FULTON...NORTHERN GWINNETT AND SOUTHERN FORSYTH
COUNTIES...

AT 836 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED THE 
HEAVY RAIN EARLIER OVER THE WARNED AREA HAS DISSIPATED AND MOVED 
TOWARD GAINESVILLE AND ATHENS. STORM TOTAL RAINFALL AMOUNTS OF 2 TO 
3 INCHES OCCURRED FROM ALPHARETTA THROUGH SUWANEE TO DACULA. 
SIGNIFICANT RISES ARE OCCURRING ON CREEKS IN THE WARNED AREA AT THIS 
TIME.

THE FLASH FLOOD WARNING WILL CONTINUE UNTIL THEY CREST AND BEGIN TO 
RECEDE LATER THIS EVENING.

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO MILTON AND 
SUWANEE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING. IF FLASH FLOODING IS OBSERVED ACT QUICKLY. MOVE
UP TO HIGHER GROUND TO ESCAPE FLOOD WATERS. DO NOT STAY IN AREAS
SUBJECT TO FLOODING WHEN WATER BEGINS RISING.

IF YOU SEE SIGNIFICANT FLOODING CALL THE NATIONAL WEATHER SERVICE
TOLL FREE AT 1 8 6 6 7 6 3 4 4 6 6. YOU CAN ALSO TWEET YOUR REPORT
USING HASHTAG GAWX.

&&

LAT...LON 3421 8398 3419 8399 3419 8405 3416 8406
      3410 8388 3412 8382 3400 8387 3393 8380
      3406 8442 3410 8442 3413 8436 3417 8436
      3419 8433 3419 8426 3424 8425

$$


16
937 
WGUS72 KFFC 120237
FFSFFC

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
1037 PM EDT FRI JUL 11 2014

GAC117-121-135-120430-
/O.CON.KFFC.FF.W.0017.000000T0000Z-140712T0430Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
FORSYTH GA-GWINNETT GA-FULTON GA-
1037 PM EDT FRI JUL 11 2014

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1230 AM EDT FOR
NORTHEASTERN FULTON...NORTHERN GWINNETT AND SOUTHERN FORSYTH
COUNTIES...

AT 1025 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
THUNDERSTORMS WITH HEAVY RAIN HAVE RETURNED TO THE EASTERN PORTION 
OF THE WARNED AREA IN GWINNETT COUNTY. THE STORMS WERE MOVING WEST
AT 5 TO 10 MPH AND MAY COVER A LARGE PORTION OF THE WARNED AREA
WITH RAIN AGAIN. RAINFALL AMOUNTS UP TO AN INCH WILL BE POSSIBLE IN
ADDITION TO THE 2 TO 3 INCHES WHICH OCCURRED EARLIER THIS EVENING.

MOST OF THE SMALL CREEKS IN THE WARNED AREA WERE BEGINNING TO 
RECEDE. HOWEVER...THE GROUND IS SATURATED AND THE ADDITIONAL RAIN 
MAY CAUSE SOME FLOODING PROBLEMS. ALSO THE CHATTAHOOCHEE RIVER HAS 
RISEN TO NEAR BANKFULL IN THE NORCROSS AREA WHICH MAY BACK UP SOME 
DRAINAGE TRIBUTARIES. THE FLASH FLOOD WARNING WILL CONTINUE.

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO MOUNTAIN 
PARK...SUGAR HILL...BUFORD...MILTON...ALPHARETTA AND CUMMING.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING. IF FLASH FLOODING IS OBSERVED ACT QUICKLY. MOVE
UP TO HIGHER GROUND TO ESCAPE FLOOD WATERS. DO NOT STAY IN AREAS
SUBJECT TO FLOODING WHEN WATER BEGINS RISING.

IF YOU SEE SIGNIFICANT FLOODING CALL THE NATIONAL WEATHER SERVICE
TOLL FREE AT 1 8 6 6 7 6 3 4 4 6 6. YOU CAN ALSO TWEET YOUR REPORT
USING HASHTAG GAWX.

&&

LAT...LON 3421 8398 3419 8399 3419 8405 3416 8406
      3410 8388 3412 8382 3400 8387 3393 8380
      3406 8442 3410 8442 3413 8436 3417 8436
      3419 8433 3419 8426 3424 8425

$$


16

The office that day

Everything else NWS Atlanta, GA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 10, 9:06 PM EDTSpecial Weather StatementFFCFloyd39 min
Jul 10, 9:57 PM EDTSpecial Weather StatementFFCFloyd63 min
Jul 10, 10:15 PM EDTFlash Flood WarningFFCFloyd6 hr
Jul 10, 10:33 PM EDTSpecial Weather StatementFFCHeard42 min
Jul 10, 11:04 PM EDTSpecial Weather StatementFFCWhite41 min
Jul 11, 12:00 AM EDTSpecial Weather StatementFFCLumpkin30 min
Jul 11, 2:47 PM EDTSpecial Weather StatementFFCClayton, Fayette28 min
Jul 11, 2:52 PM EDTSpecial Weather StatementFFCMeriwether, Troup38 min
Jul 11, 3:25 PM EDTSpecial Weather StatementFFCFayette, Spalding35 min
Jul 11, 3:28 PM EDTSpecial Weather StatementFFCCarroll, Douglas32 min
Jul 11, 4:05 PM EDTSpecial Weather StatementFFCDouglas25 min
Jul 11, 4:30 PM EDTSpecial Weather StatementFFCCobb, Douglas, Fulton, Paulding30 min
Jul 11, 4:51 PM EDTSpecial Weather StatementFFCCherokee24 min
Jul 11, 5:02 PM EDTSpecial Weather StatementFFCCobb, Douglas, Fulton, Paulding28 min
Jul 11, 5:32 PM EDTSpecial Weather StatementFFCCobb28 min
Jul 11, 6:01 PM EDTSpecial Weather StatementFFCCherokee29 min
Jul 11, 6:23 PM EDTSpecial Weather StatementFFCLaurens, Treutlen, Wheeler37 min
Jul 11, 7:30 PM EDTSpecial Weather StatementFFCBarrow30 min

Nearby

Flash Flood Warnings in Georgia, 2014Every flash flood warning in 2014

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.