Alert archive / North Carolina / Flash Flood Warnings in 2003

Flash Flood Warning 43, NWS Raleigh, NC

July 29, 2003Forsyth County, North Carolina

NWS Raleigh, NC issued this flash flood warning at Jul 29, 2003, 6:45 PM EDT for Forsyth County, North Carolina. It was in force for 2 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Jul 29, 2003, 6:45 PM EDT (22:45 UTC)
Expired: Jul 29, 2003, 8:45 PM EDT
In force: 2 hr
Issued by: NWS Raleigh, NC
Area: Whole counties

County Forsyth County, NC

The radar

The Roanoke radar (KFCX), 99 km from the middle of the area, began a volume at 22:45 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

Greensboro/Hi Pt, NC (KGSO), launched 12:00Z, 10.8 hours before the alert went out and 32 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 681 J/kg
Mixed-layer CIN: -58 J/kg
Mixed-layer LCL: 1045 m above ground
0-6 km bulk shear: 32 kt
0-1 km storm-relative helicity: -3 m²/s²
0-3 km storm-relative helicity: 54 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 0.4

Open this sounding in Storm Lab

The text

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

000 
WGUS52 KRAH 292247
FFWRAH
NCC067-300045-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE RALEIGH NC
645 PM EDT TUE JUL 29 2003

THE NATIONAL WEATHER SERVICE IN RALEIGH HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  FORSYTH COUNTY IN CENTRAL NORTH CAROLINA

* UNTIL 845 PM EDT

* AT 645 PM EDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
THUNDERSTORMS WITH VERY HEAVY RAIN OVER FORSYTH COUNTY AND MOVING 
INTO FORSYTH COUNTY FROM THE SOUTH.

* SLOW MOVING THUNDERSTORMS WILL PRODUCE FLOODING AROUND...
  WINSTON-SALEM
  RURAL HALL
  PFAFFTOWN
  CLEMMONS
  BELEWS CREEK

MOST FLOOD DEATHS OCCUR IN AUTOMOBILES. NEVER DRIVE YOUR VEHICLE INTO
AREAS WHERE THE WATER COVERS THE ROADWAY. THE WATER IS USUALLY DEEPER
THAN IT APPEARS. JUST ONE FOOT OF FLOWING WATER IS POWERFUL ENOUGH TO
SWEEP MOST VEHICLES OFF THE ROAD. VEHICLES CAUGHT IN RISING WATER
SHOULD BE ABANDONED.

SMALL CREEKS AND STREAMS WILL RAPIDLY FLOOD...POSSIBLY WASHING OUT
ROADS AND FLOODING NEARBY LOW AREAS. THOSE LIVING IN FLOOD PRONE
AREAS OR NEARBY FLOODING CREEKS AND STREAM SHOULD MOVE TO HIGHER
GROUND IMMEDIATELY.
&&
THIS FLASH FLOOD WARNING REPLACES A SMALL STREAM AND URBAN FLOOD 
ADVISORY ISSUED EARLIER FOR FORSYTH COUNTY.
$$

RFG

1 follow-up statement

000 
WGUS72 KRAH 292308
FFSRAH
NCC067-300030-

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE RALEIGH NC
703 PM EDT TUE JUL 29 2003

...A FLASH FLOOD WARNING CONTINUES IN EFFECT FOR FORSYTH COUNTY...

LOCATIONS THREATENED WITH FLASH FLOODING 
INCLUDE...WINSTON-SALEM...RURAL HALL...PFAFFTOWN...LEWISVILLE... 
CLEMMONS...BELEWS CREEK.

VERY HEAVY RAINFALL FROM THUNDERSTORMS CONTINUES ESPECIALLY OVER 
SOUTHERN AND WESTERN PORTIONS OF FORSYTH COUNTY.  RAINFALL RATES OF 
2 TO 4 INCHES AN HOUR ARE POSSIBLE WITH THESE STORMS. 

CREEKS LIKELY TO BE FLOODED INCLUDE ELLISON...BLACKS...DOUBLE...AND 
BLANKET CREEKS AND MUDDY AND SALEM CREEKS...ALL IN THE SOUTHWEST 
PORTION OF FORSYTH COUNTY.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE EXPERIENCING FLOODING OR LIVE IN A FLOOD PRONE AREA MOVE
TO HIGHER GROUND IMMEDIATELY.

MOST FLOOD DEATHS OCCUR IN AUTOMOBILES. NEVER DRIVE YOUR VEHICLE INTO
AREAS WHERE THE WATER COVERS THE ROADWAY. THE WATER IS USUALLY DEEPER
THAN IT APPEARS. VEHICLES CAUGHT IN RISING WATER SHOULD BE ABANDONED.

SMALL CREEKS AND STREAMS WILL RAPIDLY FLOOD...POSSIBLY WASHING OUT
ROADS AND FLOODING NEARBY LOW AREAS. THOSE LIVING IN FLOOD PRONE
AREAS OR NEARBY FLOODING CREEKS AND STREAM SHOULD MOVE TO HIGHER
GROUND IMMEDIATELY.

$$
RFG

The office that day

Everything else NWS Raleigh, NC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 29, 3:33 PM EDT	Flash Flood Warning	RAH	Wake	87 min
Jul 29, 7:11 PM EDT	Severe Thunderstorm Warning	RAH	Stanly	34 min
Jul 29, 7:27 PM EDT	Flash Flood Warning	RAH	Davidson	2 hr
Jul 29, 7:48 PM EDT	Severe Thunderstorm Warning	RAH	Stanly	37 min

Nearby

Flash Flood Warnings in North Carolina, 2003 Every flash flood warning in 2003

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.