Alert archive / Virginia / Flash Flood Warnings in 1998

Flash Flood Warning 39, NWS Baltimore/Washington

February 4, 1998King George County, Virginia

NWS Baltimore/Washington issued this flash flood warning at Feb 4, 1998, 9:22 AM EST for King George County, Virginia. It was in force for 5 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
Feb 4, 1998, 9:22 AM EST (14:22 UTC)
Expired
Feb 4, 1998, 2:05 PM EST
In force
5 hr
Issued by
NWS Baltimore/Washington
Area
Whole counties

County King George County, VA

The radar

The Sterling radar (KLWX), 83 km from the middle of the area, began a volume at 14:24 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

Washington/Dulle, VA (KIAD), launched 12:00Z, 2.4 hours before the alert went out and 78 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, Washington/Dulle, VA at 12:00Z on 1998-02-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Washington/Dulle, VA at 12:00Z on 1998-02-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 370 square meters per square second.193958Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
669 m above ground
0-6 km bulk shear
50 kt
0-1 km storm-relative helicity
370 m²/s²
0-3 km storm-relative helicity
474 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.

000 
TTAA00 KWBC 041423
FFWWBC
DCC001-MDC003-009-017-027-031-033-037-VAC003-013-059-061-099-
107-125-153-157-177-179-510-540-600-610-630-683-041905-

BULLETIN - EAS ACTIVATION REQUESTED
FLOOD WARNING
NATIONAL WEATHER SERVICE BALTIMORE/WASHINGTON DC
922 AM EST WED FEB 4 1998

THE NATIONAL WEATHER SERVICE IN BALTIMORE/WASHINGTON DC HAS ISSUED
A FLOOD WARNING EFFECTIVE UNTIL 205 PM EST FOR PEOPLE IN THE
FOLLOWING LOCATIONS...

IN CENTRAL MARYLAND

   ...MONTGOMERY COUNTY
   ...HOWARD COUNTY
   ...PRINCE GEORGES COUNTY INCLUDING THE DISTRICT OF COLUMBIA

IN EAST CENTRAL MARYLAND

   ...ANNE ARUNDEL COUNTY

IN SOUTHERN MARYLAND

   ...CHARLES COUNTY
   ...ST MARYS COUNTY
   ...CALVERT COUNTY

IN WEST CENTRAL VIRGINIA

   ...NELSON COUNTY
   ...ALBEMARLE COUNTY INCLUDING CHARLOTTESVILLE

IN NORTHWESTERN VIRGINIA

   ...RAPPAHANNOCK COUNTY

IN NORTHERN VIRGINIA

   ...LOUDOUN COUNTY
   ...ARLINGTON COUNTY
   ...FAIRFAX COUNTY INCLUDING FAIRFAX CITY...ALEXANDRIA AND FALLS
      CHURCH
   ...PRINCE WILLIAM COUNTY INCLUDING MANASSAS

IN NORTH CENTRAL VIRGINIA

   ...STAFFORD COUNTY
   ...SPOTSYLVANIA COUNTY INCLUDING FREDERICKSBURG
   ...FAUQUIER COUNTY
   ...KING GEORGE COUNTY

 
HEAVY RAIN WILL CONTINUE MOVING NORTH THROUGH THE AREA INTO THE
AFTERNOON HOURS. MANY SMALL STREAMS AND CREEKS THROUGHOUT THE
REGION ARE ALREADY APPROACHING BANKFULL AND WILL CONTINUE TO RISE
THROUGH EARLY AFTERNOON.

ONLY 1 TO 3 INCHES OF RAINFALL IS NEEDED IN 3 HOURS OR LESS TO
INITIATE FLOODING. THIS AMOUNT OF RAINFALL IS HIGHLY LIKELY
TODAY AND WILL CAUSE MANY CREEKS AND STREAMS TO LEAVE THEIR
BANKS. RIVERS WILL ALSO BE ON THE RISE THROUGH THE
AFTERNOON.

INUNDATION OF MANY ROADWAYS IS LIKELY THROUGH THE AFTERNOON.

IF YOU OBSERVE FLOODING MOVE TO HIGHER GROUND IMMEDIATELY!
DO NOT DRIVE THROUGH FLOODED ROADWAYS. THE WATER MAY BE TOO DEEP
TO CROSS SAFELY.

STAY TUNED TO NOAA WEATHER RADIO AND LOCAL MEDIA OUTLETS FOR
FURTHER UPDATES ON THIS FLOODING SITUATION.

The office that day

Everything else NWS Baltimore/Washington issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Feb 4, 7:52 AM ESTFlash Flood WarningLWXGreene, Madison, Orange4 hr
Feb 4, 7:52 AM ESTFlash Flood WarningLWXCulpeper4 hr
Feb 4, 9:22 AM ESTFlash Flood WarningLWXFairfax, Fauquier, Loudoun, Prince William, Stafford, City of Manassas5 hr
Feb 4, 9:22 AM ESTFlash Flood WarningLWXArlington, City of Alexandria, City of Falls Church5 hr
Feb 4, 9:22 AM ESTFlash Flood WarningLWXCity of Fairfax5 hr
Feb 4, 9:22 AM ESTFlash Flood WarningLWXAlbemarle, City of Charlottesville5 hr
Feb 4, 9:22 AM ESTFlash Flood WarningLWXNelson5 hr
Feb 4, 9:22 AM ESTFlash Flood WarningLWXRappahannock5 hr
Feb 4, 9:22 AM ESTFlash Flood WarningLWXSpotsylvania, City of Fredericksburg5 hr
Feb 4, 11:51 AM ESTFlash Flood WarningLWXCulpeper, Greene, Madison, Orange6 hr
Feb 4, 2:00 PM ESTFlash Flood WarningLWXFauquier, King George, Prince William, Spotsylvania, Stafford, City of Fredericksburg10 hr
Feb 4, 2:00 PM ESTFlash Flood WarningLWXAlbemarle, Nelson, City of Charlottesville10 hr
Feb 4, 2:00 PM ESTFlash Flood WarningLWXCity of Manassas10 hr
Feb 4, 2:00 PM ESTFlash Flood WarningLWXFairfax, City of Fairfax10 hr
Feb 4, 2:00 PM ESTFlash Flood WarningLWXArlington, City of Falls Church10 hr
Feb 4, 2:00 PM ESTFlash Flood WarningLWXRappahannock10 hr
Feb 4, 2:00 PM ESTFlash Flood WarningLWXLoudoun10 hr
Feb 4, 2:00 PM ESTFlash Flood WarningLWXCity of Alexandria10 hr
Feb 4, 5:35 PM ESTFlash Flood WarningLWXCulpeper, Greene, Madison, Orange6 hr

Nearby

Flash Flood Warnings in Virginia, 1998Every flash flood warning in 1998

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.