Alert archive / Delaware / Severe Thunderstorm Warnings in 1990

Severe Thunderstorm Warning 53, NWS Wilmington, NC

October 18, 1990Sussex County, Delaware

NWS Wilmington, NC issued this severe thunderstorm warning at Oct 18, 1990, 8:19 PM EDT for Sussex County, Delaware. It was in force for 116 min.

The area

The counties it named.

The facts

Issued
Oct 18, 1990, 8:19 PM EDT (00:19 UTC)
Expired
Oct 18, 1990, 10:15 PM EDT
In force
116 min
Issued by
NWS Wilmington, NC
Area
Whole counties

County Sussex County, DE

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

Wallops Is Stn, VA (KWAL), launched 00:00Z, 0.3 hours before the alert went out and 84 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, Wallops Is Stn, VA at 00:00Z on 1990-10-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 980 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, Wallops Is Stn, VA at 00:00Z on 1990-10-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 261 square meters per square second.1939587897Sfc1 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
980 J/kg
Mixed-layer CIN
-3 J/kg
Mixed-layer LCL
631 m above ground
0-6 km bulk shear
44 kt
0-1 km storm-relative helicity
261 m²/s²
0-3 km storm-relative helicity
249 m²/s²
Significant tornado parameter
1.3
Supercell composite
7.4

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KILG 190019
SVRILG
DEC005-190215-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM AND SPECIAL MARINE WARNING
NATIONAL WEATHER SERVICE WILMINGTON DE
819 PM EDT THU OCT 18 1990
 
THE NATIONAL WEATHER SERVICE IN WILMINGTON HAS ISSUED A
SEVERE THUNDERSTORM AND SPECIAL MARINE WARNING
EFFECTIVE UNTIL 1015 PM EDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS......
 
IN SOUTH DELAWARE
 
   ...SUSSEX COUNTY
 
  AND FOR MARINE INTERESTS FROM
 
   ...FENWICK ISLAND  TO  INDIAN RIVER INLET
 
TORNADO WATCH IN EFFECT FOR DELAWARE UNTIL 9PM EDT THIS EVENING...
 
RARAD SHOWS THUNDERSTORMS WITH DOWNPOURS...NEAR GEORGETOWN SOUTHWEST
TO JUST EAST OF DELMAR DELAWARE...THESE STORMS ARE MOVING EAST THROUGH
SUSSEX COUNTY AND WILL LIKELY PRODUCE HEAVY RAIN WITH SOME STREET AND
HIGHWAY FLOODING...DANGEROUS LIGHTNING...DAMAGING WINDS AND POSSIBLE
HAIL AND MAYBE A TORNADO.
 
A SPECIAL MARINE WARNING IS ISSUED FOR BOATERS ALONG THE ATLANTIC
COAST OF DELAWARE UNTIL THESE STORMS PASS.
 
CKD
 
A TORNADO WATCH IS ALSO IN EFFECT FOR THE WARNED AREA.  REMEMBER
SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE TORNADOES
WITH LITTLE OR NO ADVANCE WARNING.  REMAIN CALM BUT BE ALERT TO
RAPIDLY CHANGING WEATHER CONDITIONS.
 
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 FLOODR ROADS QUICKLY SO
DON'T DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

In the hours before

Special weather statement, Oct 18, 6:57 PM EDT, 1 hour 22 minutes before
SPECIAL WEATHER STATEMENT AND WEATHER RADAR SUMMARY
NATIONAL WEATHER SERVICE WILMINGTON NC
657 PM EDT THU OCT 18 1990

AT 630 THIS THURSDAY EVENING...THUNDERSTORMS WITH VERY HEAVY
PRECIPITATION WERE LINING UP RAPIDLY AND INTENSIFYING FROM THE
SOUTHWEST END OF PAMLICO SOUND THROUGH CAPE LOOKOUT ALONG THE
ATLANTIC GULF STREAM EAST THROUGH SOUTH OF FYINGPAN SHOALS
LIGHT TOWER.  THE STORMS WERE MOVING RAPIDLY EAST AND NORTHEAST
ABOUT 52 MILES AN HOUR.  BOATERS ESPECIALLY SHOULD BE ALERT FOR
STRONG GUSTY WINDS AROUND PAMLICO SOUND...CARTERET COUNTY AND
ADJOINING ATLANTIC COASTAL WATERS FOR THE NEXT HOUR OR SO UNTIL
THESE STORMS PASS.

OTHER SHOWERS AND RAIN PATCHES WERE SCATTERED OVER EASTERN
NORTH CAROLINA.  THUNDERSTORMS EXTENDED FROM THE NORTHEAST PIEDMONT
OF NORTH CAROLINA NEAR DURHAM NORTHEAST INTO VIRGINIA NEAR RICHMOND.
ALL PRECIPITAITON WAS MOVING EAST AROUND 50 MILES AN HOUR.  COVERAGE
CONTINUED TO DECREASE OVER EASTERN NORTH CAROLINA.

Nearby

Severe Thunderstorm Warnings in Delaware, 1990Every 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; the sounding from the Mesonet's radiosonde archive.