Alert archive / Oklahoma / Severe Thunderstorm Warnings in 1990
Severe Thunderstorm Warning 151, NWS Shreveport, LA
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
| Time | Report | Where | Remark |
|---|---|---|---|
| May 21, 1:15 AM CDT | Hail 1.75 | Mccurtain, 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.
- 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
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.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 20, 11:27 PM CDT | Severe Thunderstorm Warning | SHV | McCurtain | 93 min |
| May 21, 12:34 AM CDT | Flash Flood Warning | SHV | McCurtain | 4 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.