Alert archive / Maryland / Flash Flood Warnings in 1990

Flash Flood Warning 9, NWS Baltimore/Washington

July 15, 1990Washington County, Maryland; Berkeley County, West Virginia

NWS Baltimore/Washington issued this flash flood warning at Jul 15, 1990, 4:49 PM EDT for Washington County, Maryland; Berkeley County, West Virginia. It was in force for 116 min.

The area

The counties it named.

The facts

Issued
Jul 15, 1990, 4:49 PM EDT (20:49 UTC)
Expired
Jul 15, 1990, 6:45 PM EDT
In force
116 min
Issued by
NWS Baltimore/Washington
Area
Whole counties

Counties Washington County, MD, Berkeley County, WV

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

Washington/Dulle, VA (KIAD), launched 12:00Z, 8.8 hours before the alert went out and 79 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 1990-07-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 130 joules per kilogram.LCLLFCEL10008507005003002001001 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 1990-07-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 143 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
130 J/kg
Mixed-layer CIN
-31 J/kg
Mixed-layer LCL
590 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
143 m²/s²
0-3 km storm-relative helicity
149 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KWBC 152049
FFWWBC
MDC043-WVC003-152245-
 
BULLETIN - EBS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE WASHINGTON DC
449 PM EDT SUN JUL 15 1990
 
THE NATIONAL WEATHER SERVICE IN WASHINGTON HAS ISSUED A
FLASH FLOOD WARNING EFFECTIVE UNTIL  645 PM EDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN WEST CENTRAL MARYLAND
 
   ...EASTERN WASHINGTON COUNTY
 
 
IN NORTHEAST WEST VIRGINIA
 
   ...BERKELEY COUNTY
 
AT 445 PM RADAR SHOWED THUNDERSTORMS OVER FREDERICK COUNTY VIRGINIA
MOVING TO THE NORTHEAST TOWARD BERKELEY AND THE EASTERN PORTION OF
WASHINGTON COUNTY. THESE STORMS ARE PRODUCING VERY HEAVY RAINS AND
HAVE PRODUCED STREET AND BASEMENT FLOODING.
 
MOST DEATHS IN FLASH FLOODING OCCUR IN AUTOMOBILES.  DO NOT
ATTEMPT TO CROSS BRIDGES...DIPS...OR LOW SPOTS IF WATER COVERS
THE ROADWAY.  NEVER TRY TO CROSS A FLOWING STREAM...EVEN A
SMALL ONE...ON FOOT.

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 15, 4:06 PM EDTFlash Flood WarningLWXWashington2 hr
Jul 15, 5:44 PM EDTFlash Flood WarningLWXFrederick61 min

Nearby

Flash Flood Warnings in Maryland, 1990Flash Flood Warnings in West Virginia, 1990Every 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.