Alert archive / Texas / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 712, NWS Norman, OK

September 1, 2020Archer County, Clay County, Texas

NWS Norman, OK issued this severe thunderstorm warning at Sep 1, 2020, 2:45 PM CDT for Archer County, Clay County, Texas. It was in force for 45 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: Sep 1, 2020, 2:45 PM CDT (19:45 UTC)
Expired: Sep 1, 2020, 3:30 PM CDT
In force: 45 min
Issued by: NWS Norman, OK
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Archer County, TX, Clay County, TX

The radar

The Altus AFB radar (KFDR), 88 km from the middle of the area, began a volume at 19:49 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

Fort Worth, TX (KFWD), launched 12:00Z, 7.8 hours before the alert went out and 145 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: 1346 J/kg
Mixed-layer CIN: -56 J/kg
Mixed-layer LCL: 919 m above ground
0-6 km bulk shear: 26 kt
0-1 km storm-relative helicity: 170 m²/s²
0-3 km storm-relative helicity: 159 m²/s²
Significant tornado parameter: 0.8
Supercell composite: 7.9

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 Sep 1, 12:06 PM CDT, 2 hours 39 minutes earlier.

Area forecast discussion, Sep 1, 12:06 PM CDT, 2 hours 39 minutes before

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Hazardous weather outlook, Sep 1, 11:35 AM CDT, 3 hours 10 minutes before

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In the hours before

Local storm report, Sep 1, 9:58 AM CDT, 4 hours 47 minutes before

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Local storm report, Sep 1, 11:07 AM CDT, 3 hours 38 minutes before

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Special weather statement, Sep 1, 2:42 PM CDT, 3 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
Aug 31, 7:00 PM CDT	Special Weather Statement	OUN	McClain	15 min
Aug 31, 7:01 PM CDT	Special Weather Statement	OUN	Canadian	29 min
Aug 31, 7:02 PM CDT	Special Weather Statement	OUN	Noble	28 min
Aug 31, 7:20 PM CDT	Special Weather Statement	OUN	Cleveland	25 min
Aug 31, 7:30 PM CDT	Severe Thunderstorm Warning	OUN	Grady, McClain	30 min
Aug 31, 7:31 PM CDT	Severe Thunderstorm Warning	OUN	McClain	29 min
Aug 31, 7:34 PM CDT	Special Weather Statement	OUN	Noble	26 min
Aug 31, 7:41 PM CDT	Severe Thunderstorm Warning	OUN	Pottawatomie, Seminole	49 min
Aug 31, 7:54 PM CDT	Special Weather Statement	OUN	Kay	21 min
Aug 31, 8:00 PM CDT	Severe Thunderstorm Warning	OUN	Grady, McClain	30 min
Aug 31, 8:04 PM CDT	Special Weather Statement	OUN	Cleveland	26 min
Aug 31, 8:14 PM CDT	Special Weather Statement	OUN	Kay	31 min
Aug 31, 8:17 PM CDT	Special Weather Statement	OUN	Grady	28 min
Aug 31, 8:21 PM CDT	Areal Flood Advisory	OUN	Canadian	3 hr
Aug 31, 8:23 PM CDT	Special Weather Statement	OUN	Garfield	22 min
Aug 31, 8:28 PM CDT	Special Weather Statement	OUN	McClain	32 min
Aug 31, 8:47 PM CDT	Special Weather Statement	OUN	Oklahoma	43 min
Aug 31, 8:57 PM CDT	Special Weather Statement	OUN	Cleveland	18 min
Aug 31, 9:05 PM CDT	Areal Flood Advisory	OUN	Canadian, Oklahoma	3 hr
Aug 31, 9:15 PM CDT	Special Weather Statement	OUN	Pottawatomie	15 min
Aug 31, 9:16 PM CDT	Special Weather Statement	OUN	Tillman	44 min
Aug 31, 9:24 PM CDT	Severe Thunderstorm Warning	OUN	Cleveland, Pottawatomie	51 min
Aug 31, 9:38 PM CDT	Special Weather Statement	OUN	Canadian	37 min
Aug 31, 9:40 PM CDT	Severe Thunderstorm Warning	OUN	Canadian	35 min
Aug 31, 9:58 PM CDT	Special Weather Statement	OUN	Canadian	17 min
Aug 31, 10:13 PM CDT	Severe Thunderstorm Warning	OUN	Canadian	32 min
Aug 31, 10:15 PM CDT	Severe Thunderstorm Warning	OUN	Pottawatomie	30 min
Aug 31, 10:33 PM CDT	Special Weather Statement	OUN	Canadian	27 min
Aug 31, 10:36 PM CDT	Special Weather Statement	OUN	Oklahoma	24 min
Aug 31, 10:42 PM CDT	Flash Flood Warning	OUN	Canadian, Oklahoma	4 hr
Aug 31, 10:45 PM CDT	Special Weather Statement	OUN	Pottawatomie, Seminole	30 min
Aug 31, 10:48 PM CDT	Areal Flood Advisory	OUN	Caddo, Canadian	3 hr
Aug 31, 10:55 PM CDT	Special Weather Statement	OUN	Blaine	35 min
Aug 31, 10:56 PM CDT	Special Weather Statement	OUN	Canadian	34 min
Aug 31, 11:00 PM CDT	Special Weather Statement	OUN	Oklahoma	30 min
Aug 31, 11:09 PM CDT	Severe Thunderstorm Warning	OUN	Hughes, Seminole	30 min
Aug 31, 11:26 PM CDT	Flash Flood Warning	OUN	Canadian	3 hr
Aug 31, 11:35 PM CDT	Special Weather Statement	OUN	Canadian	25 min
Sep 1, 12:06 AM CDT	Areal Flood Advisory	OUN	Cleveland, Oklahoma	3 hr
Sep 1, 12:14 AM CDT	Severe Thunderstorm Warning	OUN	Pontotoc, Seminole	31 min
Sep 1, 12:15 AM CDT	Severe Thunderstorm Warning	OUN	Hughes	30 min
Sep 1, 12:17 AM CDT	Tornado Warning	OUN	Hughes	28 min
Sep 1, 12:32 AM CDT	Special Weather Statement	OUN	Pontotoc	28 min
Sep 1, 12:38 AM CDT	Tornado Warning	OUN	Hughes, Pontotoc, Seminole	37 min
Sep 1, 12:41 AM CDT	Special Weather Statement	OUN	Cleveland	34 min
Sep 1, 12:44 AM CDT	Tornado Warning	OUN	Hughes	31 min
Sep 1, 12:57 AM CDT	Areal Flood Advisory	OUN	Hughes, Pontotoc, Seminole	3 hr
Sep 1, 1:29 AM CDT	Flash Flood Warning	OUN	Hughes	3 hr
Sep 1, 2:21 AM CDT	Areal Flood Warning	OUN	Canadian	9 min
Sep 1, 2:44 AM CDT	Areal Flood Warning	OUN	Canadian, Oklahoma	3 hr
Sep 1, 2:49 AM CDT	Areal Flood Warning	OUN	Canadian	3 hr
Sep 1, 4:11 AM CDT	River Flood Advisory	OUN	Pottawatomie, Seminole	3 hr
Sep 1, 4:17 AM CDT	Areal Flood Warning	OUN	Hughes	3 hr
Sep 1, 5:17 AM CDT	River Flood Advisory	OUN	Canadian, Oklahoma	15 hr
Sep 1, 5:55 AM CDT	Flash Flood Warning	OUN	Hughes, Pontotoc, Pottawatomie, Seminole	3 hr
Sep 1, 6:00 AM CDT	Flash Flood Warning	OUN	Garvin, Grady, McClain	3 hr
Sep 1, 6:48 AM CDT	Areal Flood Advisory	OUN	Atoka, Coal, Garvin, Johnston, Murray, Pontotoc	3 hr
Sep 1, 7:42 AM CDT	Areal Flood Advisory	OUN	Carter, Garvin, Murray	3 hr
Sep 1, 8:07 AM CDT	Flash Flood Warning	OUN	Atoka	3 hr
Sep 1, 8:11 AM CDT	Areal Flood Advisory	OUN	Atoka, Bryan, Johnston, Love, Marshall	3 hr
Sep 1, 8:17 AM CDT	Areal Flood Advisory	OUN	Cleveland, Pottawatomie	3 hr
Sep 1, 8:34 AM CDT	Flash Flood Warning	OUN	Carter, Murray	3 hr
Sep 1, 9:03 AM CDT	Flash Flood Warning	OUN	Love	3 hr
Sep 1, 9:50 AM CDT	Areal Flood Advisory	OUN	Atoka, Coal, Hughes, Johnston, Murray, Pontotoc	3 hr
Sep 1, 11:18 AM CDT	River Flood Warning	OUN	Pottawatomie, Seminole	15 hr
Sep 1, 11:20 AM CDT	River Flood Advisory	OUN	Lincoln, Oklahoma, Pottawatomie	22 hr
Sep 1, 2:59 PM CDT	Special Weather Statement	OUN	Harper	31 min
Sep 1, 4:03 PM CDT	Areal Flood Advisory	OUN	Carter, Garvin, Jefferson, Stephens	3 hr
Sep 1, 4:18 PM CDT	Special Weather Statement	OUN	Harper	27 min
Sep 1, 4:35 PM CDT	Areal Flood Advisory	OUN	Carter, Jefferson, Murray	3 hr
Sep 1, 4:56 PM CDT	Special Weather Statement	OUN	Harper	34 min
Sep 1, 5:14 PM CDT	Severe Thunderstorm Warning	OUN	Ellis, Harper, Woodward	46 min
Sep 1, 5:59 PM CDT	Special Weather Statement	OUN	Woodward	31 min
Sep 1, 6:06 PM CDT	Areal Flood Advisory	OUN	Johnston, Murray, Pontotoc	3 hr
Aug 31, 8:45 PM CDT	Special Weather Statement	OUN	Wilbarger	30 min
Sep 1, 2:30 PM CDT	Areal Flood Advisory	OUN	Archer, Clay	3 hr
Sep 1, 2:42 PM CDT	Special Weather Statement	OUN	Clay	33 min

Nearby

Severe Thunderstorm Warnings in Texas, 2020 Every severe thunderstorm warning in 2020

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.