Alert archive / Oklahoma / Severe Thunderstorm Warnings in 1990

Severe Thunderstorm Warning 151, NWS Shreveport, LA

May 21, 1990McCurtain County, Oklahoma

NWS Shreveport, LA issued this severe thunderstorm warning at May 21, 1990, 1:00 AM CDT for McCurtain County, Oklahoma. It was in force for 60 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
May 21, 1990, 1:00 AM CDT (06:00 UTC)
Expired
May 21, 1990, 2:00 AM CDT
In force
60 min
Issued by
NWS Shreveport, LA
Area
Whole counties

County McCurtain County, OK

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

TimeReportWhereRemark
May 21, 1:15 AM CDTHail 1.75Mccurtain, OK

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

Longview/Gregg, TX (KGGG), launched 00:00Z, 6.0 hours before the alert went out and 197 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, Longview/Gregg, TX at 00:00Z on 1990-05-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2312 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, Longview/Gregg, TX at 00:00Z on 1990-05-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 151 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
2312 J/kg
Mixed-layer CIN
-235 J/kg
Mixed-layer LCL
1408 m above ground
0-6 km bulk shear
46 kt
0-1 km storm-relative helicity
151 m²/s²
0-3 km storm-relative helicity
201 m²/s²
Significant tornado parameter
0.0
Supercell composite
3.1

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KSHV 210601
SVRSHV
OKC089-210700-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SHREVEPORT LA
100 AM CDT MON MAY 21 1990
 
THE NATIONAL WEATHER SERVICE IN SHREVEPORT HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  200 AM CDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS..
 
IN SOUTHEAST OKLAHOMA
 
   ...NORTHERN MCCURTAIN COUNTY
 
AT 1255 AM CDT WEATHER SERVICE RADARS IN SHREVEPORT AND LONGVIEW
SHOWED A SEVERE THUNDERSTORM OVER NORTH MCCURTAIN COUNTY FIVE
MILES SOUTH OF SMITHVILLE MOVING TO THE EAST AT 18 MPH. THIS
STORM HAS PRODUCED ONE HALF TO ONE INCH SIZE HAIL AT SMITVILLE
AT 1235 TO 1245 AM CDT.
 
THE STORMS HAVE ALSO PRODUCED VERY HEAVY RAINFALL THAT HAS CAUSED
SOME FLOODING OF STREETS.
 
 
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.

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, May 20, 11:21 PM CDT, 1 hour 39 minutes before
OKZ026-TXZ022-023-027-028-032-033-ARZ009-010-011-016-LAZ001-002-
003-004-005-006-210530-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SHREVEPORT LA
1120 PM CDT SUN MAY 20 1990

...A SEVERE THUNDERSTORM WATCH IN EFFECT UNTIL 400 AM CDT MONDAY
MORNING FOR PARTS OF EAST OKLAHOMA AND A LARGE PART OF CENTRAL AND
SOUTHWEST ARKANSAS...
...A FLASH FLOOD WATCH IN EFFECT TONIGHT FOR SOUTHWEST ARKANSAS...
...SHOWERS AND THUNDERSTORMS HAVE DEVELOPED OVER SOUTHWEST ARKANSAS
AND SOUTHEAST OKLAHOMA...

AT 1115 PM CDT WEATHER SERVICE RADAR IN SHREVEPORT SHOWED A BROKEN
BAND OF SHOWERS AND THUNDERSTORMS OVER SOUTHWEST ARKANSAS AND NORTHEAST
TEXAS THAT EXTENDED FROM NEAR BENTON..SHERIDAN..AND WARREN SOUTHWEST
TO NEAR PRESCOTT..HOPE..AND TEXARKANA TO NEAR NEW BOSTON TEXAS. THE
STRONGER THUNDERSTORMS WITHIN THIS BAND WERE NOTED NEAR TEXARKANA.

AT 1110 PM CDT RADAR SHOWED A BAND OF SHOWERS AND THUNDERSTORMS
OVER SOUTHEAST OKLAHOMA THAT EXTENDED FROM SOUTH OF FORT SMITH
ARKANSAS SOUTHWEST TO NEAR ANTLERS OKLAHOMA.

THE SHOWERS AND THUNDERSTORMS WERE MOVING TO THE EAST AT 30 MPH.

THE STORMS AT 1115 PM WERE APPROACHING MCCURTAIN COUNTY IN
SOUTHEAST OKLAHOMA AND A WARNING MAY BE REQUIRED DURING THE NEXT
HALF HOUR. THESE STORMS WERE PRODUCING VERY HEAVY RAINFALL WHICH
WILL CAUSE FLOODING IN A SHORT PERIOD OF TIME.

The office that day

Everything else NWS Shreveport, LA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 20, 11:27 PM CDTSevere Thunderstorm WarningSHVMcCurtain93 min
May 21, 12:34 AM CDTFlash Flood WarningSHVMcCurtain4 hr

Nearby

Severe Thunderstorm Warnings in Oklahoma, 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.