Alert archive / Delaware / Severe Thunderstorm Warnings in 1990

Severe Thunderstorm Warning 18, NWS Wilmington, NC

June 9, 1990New Castle County, Delaware

NWS Wilmington, NC issued this severe thunderstorm warning at Jun 9, 1990, 7:20 PM EDT for New Castle County, Delaware. It was in force for 40 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued: Jun 9, 1990, 7:20 PM EDT (23:20 UTC)
Expired: Jun 9, 1990, 8:00 PM EDT
In force: 40 min
Issued by: NWS Wilmington, NC
Area: Whole counties

County New Castle County, DE

The radar

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

What was reported inside it

Time	Report	Where	Remark
Jun 9, 8:00 PM EDT	Thunderstorm Wind 0	New Castle, DE

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in. Storm Data before 1996 records only tornadoes, thunderstorm wind and hail.

The nearest sounding before it

Atlantic City In, NJ (KACY), launched 12:00Z, 11.3 hours before the alert went out and 99 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: 869 J/kg
Mixed-layer CIN: -122 J/kg
Mixed-layer LCL: 729 m above ground
0-6 km bulk shear: 49 kt
0-1 km storm-relative helicity: 47 m²/s²
0-3 km storm-relative helicity: 57 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.8

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KILG 092321 RRA
SVRILG
DEC003-100000-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE WILMINGTON DE
720 PM EDT SAT JUN 9 1990
 
THE NATIONAL WEATHER SERVICE IN WILMINGTON HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  800 PM EDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS......
 
IN NORTH DELAWARE
 
   ...NEW CASTLE COUNTY
 
AN INTENSIFYING THUNDERSTORM OVER HARFORD COUNTY IN MARYLAND IS MOVING
TO THE EAST AT AROUND 20 MPH. THIS STORM IS EXPECTED TO MOVE INTO NEW
CASTLE COUNTY WITHIN THE HOUR. THE WARNING ALSO INCLUDES THE ADJACENT
WATERWAYS OF NEW CASTLE COUNTY.
 
LISTEN TO YOUR LOCAL RADIO...OR NOAA RADIO FOR FURTHER UPDATES.
 
 
SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 55
MPH...DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN.
FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR
OF YOUR HOME OR BUSINESS.  HEAVY RAINS FLOOD ROADS QUICKLY SO
DON'T DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.
 
THIS IS A DANGEROUS STORM.  IF YOU ARE IN ITS PATH YOU SHOULD
PREPARE FOR DAMAGING WIND IN EXCESS OF 55 MPH...LARGE HAIL...AND
DEADLY LIGHTNING.  PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING BUT STAY AWAY FROM WINDOWS.

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 9, 6:18 PM EDT	Severe Thunderstorm Warning	ILM	Kent	27 min

Nearby

Severe Thunderstorm Warnings in Delaware, 1990 Every severe thunderstorm 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.