Alert archive / Virginia / Flash Flood Warnings in 1990

Flash Flood Warning 2, NWS Blacksburg, VA

March 17, 1990Henry County, Virginia

NWS Blacksburg, VA issued this flash flood warning at Mar 17, 1990, 1:31 PM EST for Henry County, Virginia. It was in force for 119 min.

The area

The counties it named.

The facts

Issued: Mar 17, 1990, 1:31 PM EST (18:31 UTC)
Expired: Mar 17, 1990, 3:30 PM EST
In force: 119 min
Issued by: NWS Blacksburg, VA
Area: Whole counties

County Henry County, VA

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

The nearest sounding before it

Greensboro/Hi Pt, NC (KGSO), launched 12:00Z, 6.5 hours before the alert went out and 68 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: 98 J/kg
Mixed-layer CIN: -30 J/kg
Mixed-layer LCL: 674 m above ground
0-6 km bulk shear: 54 kt
0-1 km storm-relative helicity: 259 m²/s²
0-3 km storm-relative helicity: 308 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.3

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KROA 171833 RRA
FFWROA
VAC690-089-172030-
 
BULLETIN
SMALL STREAM AND URBAN FLOOD WARNING
NATIONAL WEATHER SERVICE ROANOKE VA
131 PM EST SAT MAR 17 1990
 
THE NATIONAL WEATHER SERVICE IN ROANOKE HAS ISSUED A
SMALL STREAM AND URBAN FLOOD WARNING EFFECTIVE UNTIL  330 PM EST
FOR PEOPLE IN THE FOLLOWING COUNTIES...
 
IN SOUTH CENTRAL VIRGINIA
          ...CITY MARTINSVILLE...HENRY
 
SOME CREEKS AND SMALL STREAMS REMAIN OUT OF THIER BANKS IN HENRY
COUNTY AS OF 120 PM...SO THE SMALL STREAM AND URBAN FLOOD WARNING IN
EFFECT HAS BEEN EXTENDED TO 330 PM. THE RAIN HAS LET UP IN HENRY
COUNTY AT THE PRESENT TIME...BUT RADAR SHOWS ANOTHER BATCH OF RAIN
JUST BEGINNING TO MOVE INTO THE WESTERN SECTIONS OF HENRY COUNTY AT
120 PM. INDICATIONS ARE THAT THIS RAIN WILL LAST ONLY ABOUT AN
HOUR...AND WILL TEND TO KEEP THE FLOODED CREEKS AND STREAMS OUT OF
THIER BANKS ANOTHER HOUR OR TWO.
 
DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY.  THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO
CROSS SAFELY. LISTEN TO NOAA WEATHER RADIO OR YOUR LOCAL NEWS MEDIA
FOR FURTHER UPDATES.
JACKSON

The office that day

Everything else NWS Blacksburg, VA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Mar 17, 11:28 AM EST	Flash Flood Warning	RNK	Henry	2 hr

Nearby

Flash Flood Warnings in Virginia, 1990 Every flash flood warning in 1990

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.