Alert archive / Oklahoma / Severe Thunderstorm Warnings in 1990
Severe Thunderstorm Warning 131, NWS Tulsa, OK
NWS Tulsa, OK issued this severe thunderstorm warning at May 20, 1990, 11:26 PM CDT for Delaware County, Oklahoma. It was in force for 34 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 20, 1990, 11:26 PM CDT (04:26 UTC)
- Expired
- May 21, 1990, 12:00 AM CDT
- In force
- 34 min
- Issued by
- NWS Tulsa, OK
- Area
- Whole counties
County Delaware 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 20, 11:50 PM CDT | Hail 0.75 | Delaware, 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
Springfield, MO (KUMN), launched 00:00Z, 4.4 hours before the alert went out and 105 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
- 2299 J/kg
- Mixed-layer CIN
- -15 J/kg
- Mixed-layer LCL
- 1348 m above ground
- 0-6 km bulk shear
- 30 kt
- 0-1 km storm-relative helicity
- 37 m²/s²
- 0-3 km storm-relative helicity
- 196 m²/s²
- Significant tornado parameter
- 0.7
- Supercell composite
- 7.8
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KTUL 210427 SVRTUL OKC041-210500- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE TULSA OK 1126 PM CDT SUN MAY 20 1990 THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL MIDNIGHT CDT FOR PEOPLE IN THE FOLLOWING COUNTIES ... IN NORTHEAST OKLAHOMA ...EASTERN DELAWARE COUNTY AT 11 25 PM CDT RADAR INDICATED A SEVERE THUNDERSTORM 6 MILES SOUTHEAST OF GROVE MOVING EA ST NORTHEAST AT 20 MPH. SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 60 MPH... LARGE HAIL...DEADLY LIGHTNING AND VERY HEAVY RAIN. FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR HOME OR BUSINESS.
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
Local storm report, May 20, 10:14 PM CDT, 1 hour 12 minutes before
STORM REPORT
NATIONAL WEATHER SERVICE TULSA, OK
1011 PM CDT SUN MAY 20 1990
TIME/CDT COUNTY EVENT
9 35 PM OTTAWA DIME TO NICKEL SIZE HAIL AT QUAPAW.
9 50 PM OTTAWA QUARTER SqIZE HAIL AT TURNPIKE TOLL BOOTH
ON OKLAHOMA-MISSOURI LINE. REPORTED THE HAIL
FALLING IN BOTH STATES.The office that day
Everything else NWS Tulsa, OK issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 20, 9:29 PM CDT | Severe Thunderstorm Warning | TSA | Ottawa | 46 min |
| May 20, 11:32 PM CDT | Severe Thunderstorm Warning | TSA | LeFlore | 58 min |
| May 21, 12:28 AM CDT | Flash Flood Warning | TSA | LeFlore | 3 hr |
| May 21, 12:39 AM CDT | Severe Thunderstorm Warning | TSA | LeFlore | 66 min |
| May 21, 2:27 AM CDT | Severe Thunderstorm Warning | TSA | Cherokee, Muskogee | 48 min |
| May 21, 2:32 AM CDT | Severe Thunderstorm Warning | TSA | Sequoyah | 58 min |
| May 21, 2:36 AM CDT | Severe Thunderstorm Warning | TSA | Adair | 39 min |
| May 21, 3:27 AM CDT | Severe Thunderstorm Warning | TSA | LeFlore, Sequoyah | 63 min |
| May 21, 4:28 AM CDT | Severe Thunderstorm Warning | TSA | LeFlore | 62 min |
| May 21, 5:27 AM CDT | Severe Thunderstorm Warning | TSA | LeFlore | 63 min |
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.