Alert archive / Oklahoma / Severe Thunderstorm Warnings in 1991
Severe Thunderstorm Warning 2, NWS Norman, OK
NWS Norman, OK issued this severe thunderstorm warning at Mar 21, 1991, 12:10 PM CST for Johnston County, Oklahoma. It was in force for 50 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
- Mar 21, 1991, 12:10 PM CST (18:10 UTC)
- Expired
- Mar 21, 1991, 1:00 PM CST
- In force
- 50 min
- Issued by
- NWS Norman, OK
- Area
- Whole counties
County Johnston County, OK
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Mar 21, 12:30 PM CST | Hail 0.88 | Johnston, 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
Norman, OK (KOUN), launched 12:00Z, 6.2 hours before the alert went out and 121 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
- 279 J/kg
- Mixed-layer CIN
- -194 J/kg
- Mixed-layer LCL
- 1274 m above ground
- 0-6 km bulk shear
- 58 kt
- 0-1 km storm-relative helicity
- -11 m²/s²
- 0-3 km storm-relative helicity
- -29 m²/s²
- Significant tornado parameter
- -0.0
- Supercell composite
- -0.0
The text
The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.
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, Mar 21, 11:07 AM CST, 1 hour 3 minutes before
OKZ004>021-221845- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE OKLAHOMA CITY OK 1100 AM CST THU MAR 21 1991 ...SEVERE THUNDRERSTORMS POSSIBLE ACROSS CENTRAL AND PORTIONS OF SOUTHWEST OKLAHOMA THIS AFTERNOON... A ABUNDANT FLOW OF MOISTURE COMBINED WITH A DEVELOPING STORM SYSTEM WILL CREATE THE POTENTIAL FOR THE FIRST SEVERE WEATHER OUTBREAK OF THE SPRING ACROSS PORTIONS OF OKLAHOMA THIS AFTERNOON. SEVERE THUNDERSTORM WITH LARGE HAIL...AND POSSIBLY TORNADOES...MAY DEVELOP THIS AFTERNOON...AS A LOW PRESSURE AREA DEVELOPING OVER KANSAS IS EXPECTED TO PUSH A DRY LINE ACROSS PORTIONS OF THE STATE THIS AFTERNOON. PERSONS IN SOUTHWEST AND CENTRAL OKLAHOMA SHOULD LISTEN FOR LATER STATEMENTS ...AND THE OKLAHOMA THUNDERSTORM OUTLOOK TO BE ISSUED AROUND 1245 PM... FOR FURTHER INFORMATION.
The office that day
Everything else NWS Norman, OK issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 21, 11:55 AM CST | Severe Thunderstorm Warning | OUN | Jefferson | 50 min |
| Mar 21, 12:16 PM CST | Severe Thunderstorm Warning | OUN | Carter | 29 min |
| Mar 21, 12:20 PM CST | Severe Thunderstorm Warning | OUN | Stephens | 25 min |
| Mar 21, 12:33 PM CST | Severe Thunderstorm Warning | OUN | Carter | 27 min |
| Mar 21, 12:50 PM CST | Severe Thunderstorm Warning | OUN | Cleveland, Pottawatomie | 40 min |
| Mar 21, 12:51 PM CST | Severe Thunderstorm Warning | OUN | Grady | 44 min |
| Mar 21, 12:52 PM CST | Severe Thunderstorm Warning | OUN | Garvin | 53 min |
| Mar 21, 12:53 PM CST | Severe Thunderstorm Warning | OUN | Jefferson | 52 min |
| Mar 21, 12:57 PM CST | Severe Thunderstorm Warning | OUN | Coal, Johnston, Pontotoc | 48 min |
| Mar 21, 1:02 PM CST | Severe Thunderstorm Warning | OUN | Comanche | 43 min |
| Mar 21, 1:06 PM CST | Severe Thunderstorm Warning | OUN | Tillman | 69 min |
| Mar 21, 1:14 PM CST | Severe Thunderstorm Warning | OUN | Carter | 46 min |
| Mar 21, 1:20 PM CST | Severe Thunderstorm Warning | OUN | McClain | 40 min |
| Mar 21, 1:25 PM CST | Severe Thunderstorm Warning | OUN | Hughes, Seminole | 50 min |
| Mar 21, 1:27 PM CST | Severe Thunderstorm Warning | OUN | Cleveland | 48 min |
| Mar 21, 1:48 PM CST | Severe Thunderstorm Warning | OUN | Pontotoc, Pottawatomie, Seminole | 42 min |
| Mar 21, 2:05 PM CST | Severe Thunderstorm Warning | OUN | Comanche, Cotton, Grady | 40 min |
| Mar 21, 2:15 PM CST | Severe Thunderstorm Warning | OUN | Cleveland, McClain | 45 min |
| Mar 21, 2:19 PM CST | Severe Thunderstorm Warning | OUN | Jefferson | 41 min |
| Mar 21, 2:38 PM CST | Severe Thunderstorm Warning | OUN | Jefferson, Stephens | 52 min |
| Mar 21, 2:40 PM CST | Severe Thunderstorm Warning | OUN | Hughes, Pontotoc, Seminole | 50 min |
| Mar 21, 2:52 PM CST | Severe Thunderstorm Warning | OUN | Oklahoma | 38 min |
| Mar 21, 3:02 PM CST | Severe Thunderstorm Warning | OUN | Garvin, Grady, Stephens | 43 min |
| Mar 21, 3:11 PM CST | Severe Thunderstorm Warning | OUN | Carter | 49 min |
| Mar 21, 3:24 PM CST | Severe Thunderstorm Warning | OUN | Jefferson | 36 min |
| Mar 21, 3:32 PM CST | Severe Thunderstorm Warning | OUN | Cleveland, McClain | 43 min |
| Mar 21, 3:40 PM CST | Severe Thunderstorm Warning | OUN | Love | 35 min |
| Mar 21, 3:43 PM CST | Severe Thunderstorm Warning | OUN | Garvin | 47 min |
| Mar 21, 3:48 PM CST | Severe Thunderstorm Warning | OUN | Lincoln | 42 min |
| Mar 21, 3:59 PM CST | Severe Thunderstorm Warning | OUN | Carter, Johnston | 61 min |
| Mar 21, 4:08 PM CST | Severe Thunderstorm Warning | OUN | Pontotoc, Pottawatomie, Seminole | 52 min |
| Mar 21, 4:08 PM CST | Severe Thunderstorm Warning | OUN | McClain | 52 min |
| Mar 21, 4:39 PM CST | Tornado Warning | OUN | Johnston, Marshall | 36 min |
| Mar 21, 4:42 PM CST | Severe Thunderstorm Warning | OUN | Love | 48 min |
| Mar 21, 4:47 PM CST | Tornado Warning | OUN | Hughes, Pontotoc | 28 min |
| Mar 21, 4:55 PM CST | Tornado Warning | OUN | Atoka | 35 min |
| Mar 21, 5:15 PM CST | Severe Thunderstorm Warning | OUN | Carter, Love | 45 min |
| Mar 21, 5:20 PM CST | Tornado Warning | OUN | Carter, Love | 25 min |
| Mar 21, 5:26 PM CST | Tornado Warning | OUN | Atoka | 34 min |
| Mar 21, 5:36 PM CST | Tornado Warning | OUN | Marshall | 39 min |
| Mar 21, 5:52 PM CST | Severe Thunderstorm Warning | OUN | Pushmataha | 68 min |
| Mar 21, 5:58 PM CST | Tornado Warning | OUN | Johnston | 32 min |
Nearby
Severe Thunderstorm Warnings in Oklahoma, 1991Every severe thunderstorm warning in 1991
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.