Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2023

Severe Thunderstorm Warning 155, NWS Norman, OK

April 20, 2023Logan County, Payne County, Oklahoma

NWS Norman, OK issued this severe thunderstorm warning at Apr 20, 2023, 5:35 AM CDT for Logan County, Payne County, Oklahoma. It was in force for 40 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Apr 20, 2023, 5:35 AM CDT (10:35 UTC)
Expired: Apr 20, 2023, 6:15 AM CDT
In force: 40 min
Issued by: NWS Norman, OK
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Logan County, OK, Payne County, OK

The radar

The Norman radar (KTLX), 74 km from the middle of the area, began a volume at 10:38 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Norman, OK (KOUN), launched 00:00Z, 10.6 hours before the alert went out and 88 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1620 J/kg
Mixed-layer CIN: -30 J/kg
Mixed-layer LCL: 1145 m above ground
0-6 km bulk shear: 62 kt
0-1 km storm-relative helicity: 427 m²/s²
0-3 km storm-relative helicity: 523 m²/s²
Significant tornado parameter: 4.0
Supercell composite: 19.0

Open this sounding in Storm Lab

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.

NWS Norman, OK wrote its last area forecast discussion before this severe thunderstorm warning went out at Apr 20, 2:50 AM CDT, 2 hours 45 minutes earlier.

Area forecast discussion, Apr 20, 2:50 AM CDT, 2 hours 45 minutes before

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Hazardous weather outlook, Apr 20, 3:14 AM CDT, 2 hours 21 minutes before

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In the hours before

Local storm report, Apr 20, 12:06 AM CDT, 5 hours 29 minutes before

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Local storm report, Apr 20, 12:39 AM CDT, 4 hours 56 minutes before

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Local storm report, Apr 20, 4:45 AM CDT, 50 minutes before

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Special weather statement, Apr 20, 4:53 AM CDT, 42 minutes before

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Special weather statement, Apr 20, 5:17 AM CDT, 18 minutes before

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The office that day

Everything else NWS Norman, OK issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 19, 7:03 PM CDT	Tornado Warning	OUN	Cleveland, Oklahoma	42 min
Apr 19, 7:05 PM CDT	Severe Thunderstorm Warning	OUN	Comanche, Cotton, Tillman	40 min
Apr 19, 7:15 PM CDT	Tornado Warning	OUN	Cleveland, Grady, McClain	45 min
Apr 19, 7:20 PM CDT	Severe Thunderstorm Warning	OUN	Lincoln, Logan, Oklahoma	40 min
Apr 19, 7:27 PM CDT	Severe Thunderstorm Warning Destructive damage threat	OUN	Cleveland, Grady, McClain	48 min
Apr 19, 7:32 PM CDT	Severe Thunderstorm Warning	OUN	Noble	43 min
Apr 19, 7:34 PM CDT	Tornado Warning	OUN	Cleveland, McClain	26 min
Apr 19, 7:43 PM CDT	Severe Thunderstorm Warning	OUN	Lincoln, Oklahoma	47 min
Apr 19, 7:45 PM CDT	Severe Thunderstorm Warning	OUN	Cotton, Jefferson, Stephens	45 min
Apr 19, 7:46 PM CDT	Severe Thunderstorm Warning	OUN	Cotton, Jefferson, Stephens	44 min
Apr 19, 7:46 PM CDT	Severe Thunderstorm Warning	OUN	Comanche, Cotton, Grady, Stephens	44 min
Apr 19, 7:50 PM CDT	Severe Thunderstorm Warning	OUN	Canadian, Cleveland, Oklahoma	40 min
Apr 19, 7:56 PM CDT	Tornado Warning Tornado observedConsiderable damage threat	OUN	Cleveland, McClain	18 min
Apr 19, 7:59 PM CDT	Tornado Warning Tornado observedConsiderable damage threat	OUN	Cleveland, McClain	16 min
Apr 19, 8:01 PM CDT	Tornado Warning	OUN	Cleveland, McClain	44 min
Apr 19, 8:05 PM CDT	Severe Thunderstorm Warning	OUN	Logan, Noble, Payne	40 min
Apr 19, 8:15 PM CDT	Severe Thunderstorm Warning Considerable damage threat	OUN	Cleveland, McClain	45 min
Apr 19, 8:19 PM CDT	Areal Flood Advisory	OUN	Cleveland, Oklahoma	3 hr
Apr 19, 8:24 PM CDT	Severe Thunderstorm Warning	OUN	Canadian, Cleveland, Oklahoma	51 min
Apr 19, 8:25 PM CDT	Severe Thunderstorm Warning Considerable damage threat	OUN	Comanche, Grady, Stephens	50 min
Apr 19, 8:36 PM CDT	Severe Thunderstorm Warning	OUN	Cotton, Stephens	39 min
Apr 19, 8:39 PM CDT	Tornado Warning	OUN	Cleveland, Pottawatomie	51 min
Apr 19, 8:44 PM CDT	Severe Thunderstorm Warning Considerable damage threat	OUN	Cleveland, Pottawatomie	46 min
Apr 19, 8:46 PM CDT	Wind Advisory	OUN	Alfalfa, Blaine, Canadian, Dewey, Ellis, Garfield and 13 more	10 hr
Apr 19, 8:47 PM CDT	Severe Thunderstorm Warning	OUN	Cleveland, Oklahoma	43 min
Apr 19, 8:55 PM CDT	Tornado Warning Tornado observedConsiderable damage threat	OUN	Cleveland, Pottawatomie	35 min
Apr 19, 9:09 PM CDT	Tornado Warning	OUN	Cleveland, Pottawatomie	36 min
Apr 19, 9:12 PM CDT	Tornado Warning	OUN	Pottawatomie	48 min
Apr 19, 9:18 PM CDT	Tornado Warning	OUN	Cleveland, Pottawatomie	27 min
Apr 19, 9:24 PM CDT	Tornado Warning	OUN	Pottawatomie	51 min
Apr 19, 9:31 PM CDT	Tornado Warning	OUN	Cleveland, Pottawatomie	29 min
Apr 19, 9:43 PM CDT	Tornado Warning	OUN	Pottawatomie	32 min
Apr 19, 9:59 PM CDT	Areal Flood Advisory	OUN	Pottawatomie	3 hr
Apr 19, 10:02 PM CDT	Tornado Warning Tornado observedConsiderable damage threat	OUN	Lincoln, Pottawatomie	13 min
Apr 19, 10:12 PM CDT	Tornado Warning Tornado observedConsiderable damage threat	OUN	Lincoln, Pottawatomie	14 min
Apr 19, 10:13 PM CDT	Severe Thunderstorm Warning Considerable damage threat	OUN	Lincoln, Pottawatomie, Seminole	47 min
Apr 19, 10:28 PM CDT	Severe Thunderstorm Warning	OUN	Lincoln, Pottawatomie	32 min
Apr 19, 10:37 PM CDT	Tornado Warning	OUN	Lincoln, Pottawatomie	16 min
Apr 19, 10:56 PM CDT	Severe Thunderstorm Warning Considerable damage threat	OUN	Lincoln, Pottawatomie	34 min
Apr 19, 11:19 PM CDT	Areal Flood Advisory	OUN	Lincoln, Pottawatomie	3 hr
Apr 20, 4:53 AM CDT	Special Weather Statement	OUN	Logan	37 min
Apr 20, 5:17 AM CDT	Special Weather Statement	OUN	Logan	28 min
Apr 20, 6:10 AM CDT	Special Weather Statement	OUN	Logan	35 min
Apr 20, 6:20 AM CDT	Special Weather Statement	OUN	Payne	25 min
Apr 20, 6:39 AM CDT	Special Weather Statement	OUN	Lincoln	36 min
Apr 20, 7:05 AM CDT	Special Weather Statement	OUN	McClain	25 min
Apr 20, 7:37 AM CDT	Special Weather Statement	OUN	Garvin	38 min
Apr 20, 2:11 PM CDT	Special Weather Statement	OUN	Bryan	34 min
Apr 20, 7:00 AM CDT	Special Weather Statement	OUN	Baylor	30 min

Nearby

Severe Thunderstorm Warnings in Oklahoma, 2023 Every severe thunderstorm warning in 2023

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; radar from the NEXRAD Level II archive.