Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2023

Severe Thunderstorm Warning 539, NWS Norman, OK

July 7, 20239 counties in Oklahoma

NWS Norman, OK issued this severe thunderstorm warning at Jul 7, 2023, 8:54 PM CDT for 9 counties in Oklahoma. It was in force for 51 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: Jul 7, 2023, 8:54 PM CDT (01:54 UTC)
Expired: Jul 7, 2023, 9:45 PM CDT
In force: 51 min
Issued by: NWS Norman, OK
Area: Storm-based polygon
Damage threat: Considerable
Hail: 0.75 in
Wind: 70.0 mph

Counties Beckham County, OK, Custer County, OK, Dewey County, OK, Ellis County, OK, Kiowa County, OK, Major County, OK, Roger Mills County, OK, Washita County, OK, Woodward County, OK

The radar

The Vance AFB radar (KVNX), 147 km from the middle of the area, began a volume at 01:57 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Jul 7, 6:54 PM CDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Norman, OK (KOUN), launched 00:00Z, 1.9 hours before the alert went out and 174 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: 1301 J/kg
Mixed-layer CIN: -119 J/kg
Mixed-layer LCL: 953 m above ground
0-6 km bulk shear: 29 kt
0-1 km storm-relative helicity: 18 m²/s²
0-3 km storm-relative helicity: 55 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.6

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 Jul 7, 5:57 PM CDT, 2 hours 57 minutes earlier.

Area forecast discussion, Jul 7, 5:57 PM CDT, 2 hours 57 minutes before

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Hazardous weather outlook, Jul 7, 1:50 PM CDT, 7 hours 4 minutes before

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In the hours before

Special weather statement, Jul 7, 3:02 PM CDT, 5 hours 52 minutes before

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Special weather statement, Jul 7, 6:45 PM CDT, 2 hours 9 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
Jul 7, 7:33 PM CDT	Severe Thunderstorm Warning Considerable damage threat	OUN	Beckham, Ellis, Greer, Roger Mills	42 min
Jul 7, 7:41 PM CDT	Severe Thunderstorm Warning Destructive damage threat	OUN	Ellis	49 min
Jul 7, 8:13 PM CDT	Severe Thunderstorm Warning	OUN	Beckham, Custer, Dewey, Ellis, Roger Mills, Washita and 1 more	47 min
Jul 7, 8:18 PM CDT	Severe Thunderstorm Warning Considerable damage threat	OUN	Beckham, Greer, Harmon, Jackson, Washita	42 min
Jul 7, 8:43 PM CDT	Areal Flood Advisory	OUN	Ellis, Harper	3 hr
Jul 7, 8:54 PM CDT	Severe Thunderstorm Warning Destructive damage threat	OUN	Greer, Harmon, Jackson	51 min
Jul 7, 8:57 PM CDT	Areal Flood Advisory	OUN	Beckham, Custer, Dewey, Ellis, Roger Mills, Washita and 1 more	3 hr
Jul 7, 9:25 PM CDT	Severe Thunderstorm Warning Considerable damage threat	OUN	Blaine, Caddo, Canadian, Custer, Dewey, Kingfisher and 2 more	65 min
Jul 7, 9:28 PM CDT	Severe Thunderstorm Warning	OUN	Comanche, Jackson, Kiowa, Tillman	47 min
Jul 7, 9:39 PM CDT	Flash Flood Warning	OUN	Beckham, Custer, Roger Mills, Washita	3 hr
Jul 7, 10:06 PM CDT	Severe Thunderstorm Warning Considerable damage threat	OUN	Comanche, Cotton, Tillman	39 min
Jul 7, 10:18 PM CDT	Severe Thunderstorm Warning	OUN	Caddo, Comanche, Grady, Kiowa, Washita	42 min
Jul 7, 10:23 PM CDT	Special Weather Statement	OUN	Blaine, Canadian, Kingfisher	52 min
Jul 7, 10:31 PM CDT	Special Weather Statement	OUN	Alfalfa, Garfield, Grant, Major	59 min
Jul 7, 10:35 PM CDT	Areal Flood Advisory	OUN	Blaine, Dewey, Kingfisher	3 hr
Jul 7, 10:42 PM CDT	Special Weather Statement	OUN	Cotton	48 min
Jul 7, 10:56 PM CDT	Special Weather Statement	OUN	Caddo, Grady, McClain	49 min
Jul 7, 11:08 PM CDT	Special Weather Statement	OUN	Cleveland, Garvin, Grady, McClain, Oklahoma	52 min
Jul 7, 11:35 PM CDT	Special Weather Statement	OUN	Jefferson, Stephens	25 min
Jul 7, 11:55 PM CDT	Special Weather Statement	OUN	Alfalfa, Garfield	65 min
Jul 7, 11:58 PM CDT	Special Weather Statement	OUN	Cleveland, Garvin, McClain, Pottawatomie	47 min
Jul 8, 12:13 AM CDT	Severe Thunderstorm Warning	OUN	Pottawatomie, Seminole	26 min
Jul 8, 12:20 AM CDT	Special Weather Statement	OUN	Carter, Murray	25 min
Jul 8, 12:52 AM CDT	Special Weather Statement	OUN	Carter, Garvin, Murray	38 min
Jul 8, 4:39 AM CDT	Areal Flood Advisory	OUN	Caddo, Comanche	3 hr
Jul 8, 8:55 AM CDT	River Flood Warning	OUN	Woodward	36 hr
Jul 8, 8:59 AM CDT	River Flood Advisory	OUN	Custer, Washita	23 hr
Jul 8, 12:59 PM CDT	Flood Watch	OUN	Blaine, Caddo, Canadian, Custer, Dewey, Ellis and 8 more	19 hr
Jul 8, 3:29 PM CDT	Special Weather Statement	OUN	Bryan	46 min
Jul 8, 3:31 PM CDT	Areal Flood Advisory	OUN	Bryan	3 hr
Jul 8, 3:43 PM CDT	Flash Flood Warning	OUN	Bryan	3 hr
Jul 8, 4:03 PM CDT	Severe Thunderstorm Warning	OUN	Bryan	27 min
Jul 8, 6:39 PM CDT	Areal Flood Warning	OUN	Bryan	3 hr
Jul 7, 9:11 PM CDT	Special Weather Statement	OUN	Hardeman	34 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.