Alert archive / Texas / Severe Thunderstorm Warnings in 2015

Severe Thunderstorm Warning 137, NWS Norman, OK

April 17, 2015Knox County, Texas

NWS Norman, OK issued this severe thunderstorm warning at Apr 17, 2015, 11:24 AM CDT for Knox County, Texas. 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 17, 2015, 11:24 AM CDT (16:24 UTC)
Expired: Apr 17, 2015, 12:04 PM CDT
In force: 40 min
Issued by: NWS Norman, OK
Area: Storm-based polygon
Hail: 1.75 in
Wind: 60.0 mph

County Knox County, TX

The radar

The Altus AFB radar (KFDR), 110 km from the middle of the area, began a volume at 16:26 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, 4.4 hours before the alert went out and 244 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: 107 J/kg
Mixed-layer CIN: -344 J/kg
Mixed-layer LCL: 910 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 120 m²/s²
0-3 km storm-relative helicity: 111 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.3

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 17, 10:34 AM CDT, 50 minutes earlier.

Area forecast discussion, Apr 17, 10:34 AM CDT, 50 minutes before

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Hazardous weather outlook, Apr 17, 8:53 AM CDT, 2 hours 31 minutes before

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In the hours before

Special weather statement, Apr 17, 9:53 AM CDT, 1 hour 31 minutes before

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Local storm report, Apr 17, 10:01 AM CDT, 1 hour 23 minutes before

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Special weather statement, Apr 17, 10:08 AM CDT, 1 hour 16 minutes before

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Special weather statement, Apr 17, 10:43 AM CDT, 41 minutes before

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Special weather statement, Apr 17, 10:47 AM CDT, 37 minutes before

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Local storm report, Apr 17, 11:04 AM CDT, 20 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 16, 7:07 PM CDT	Special Weather Statement	OUN	Alfalfa	23 min
Apr 16, 7:25 PM CDT	Special Weather Statement	OUN	Beckham	20 min
Apr 16, 7:32 PM CDT	Severe Thunderstorm Warning	OUN	Beckham, Greer	43 min
Apr 16, 7:33 PM CDT	Special Weather Statement	OUN	Woods	27 min
Apr 16, 7:37 PM CDT	Special Weather Statement	OUN	Harper	23 min
Apr 16, 7:40 PM CDT	Special Weather Statement	OUN	Alfalfa	35 min
Apr 16, 7:42 PM CDT	Severe Thunderstorm Warning	OUN	Beckham, Custer, Ellis, Roger Mills, Woodward	63 min
Apr 16, 7:47 PM CDT	Special Weather Statement	OUN	Woodward	28 min
Apr 16, 8:01 PM CDT	Tornado Warning	OUN	Beckham	29 min
Apr 16, 8:03 PM CDT	Flash Flood Warning	OUN	Woods, Woodward	3 hr
Apr 16, 8:05 PM CDT	Areal Flood Advisory	OUN	Ellis, Roger Mills, Woodward	3 hr
Apr 16, 8:35 PM CDT	Tornado Warning	OUN	Roger Mills	40 min
Apr 16, 8:36 PM CDT	Special Weather Statement	OUN	Alfalfa	24 min
Apr 16, 8:54 PM CDT	Special Weather Statement	OUN	Woods	36 min
Apr 16, 8:58 PM CDT	Severe Thunderstorm Warning	OUN	Alfalfa	47 min
Apr 16, 9:08 PM CDT	Special Weather Statement	OUN	Alfalfa	37 min
Apr 16, 9:11 PM CDT	Tornado Warning	OUN	Beckham, Roger Mills	49 min
Apr 16, 9:20 PM CDT	Areal Flood Advisory	OUN	Roger Mills	3 hr
Apr 16, 9:31 PM CDT	Special Weather Statement	OUN	Woods	29 min
Apr 16, 9:36 PM CDT	Special Weather Statement	OUN	Woods	24 min
Apr 16, 9:54 PM CDT	Special Weather Statement	OUN	Grant	36 min
Apr 16, 9:57 PM CDT	Severe Thunderstorm Warning	OUN	Beckham, Custer, Dewey, Ellis, Roger Mills	48 min
Apr 16, 10:01 PM CDT	Special Weather Statement	OUN	Alfalfa	29 min
Apr 16, 10:27 PM CDT	Special Weather Statement	OUN	Alfalfa	33 min
Apr 16, 10:44 PM CDT	Severe Thunderstorm Warning	OUN	Dewey	25 min
Apr 16, 10:52 PM CDT	Special Weather Statement	OUN	Alfalfa	38 min
Apr 16, 11:09 PM CDT	Special Weather Statement	OUN	Grant	36 min
Apr 16, 11:40 PM CDT	Special Weather Statement	OUN	Garfield	35 min
Apr 16, 11:45 PM CDT	Special Weather Statement	OUN	Major	30 min
Apr 16, 11:47 PM CDT	Special Weather Statement	OUN	Grant	28 min
Apr 17, 12:39 AM CDT	Areal Flood Advisory	OUN	Garfield	3 hr
Apr 17, 12:42 AM CDT	Special Weather Statement	OUN	Dewey	33 min
Apr 17, 1:00 AM CDT	Special Weather Statement	OUN	Ellis	30 min
Apr 17, 1:17 AM CDT	Special Weather Statement	OUN	Roger Mills	28 min
Apr 17, 1:25 AM CDT	Severe Thunderstorm Warning	OUN	Ellis, Roger Mills	50 min
Apr 17, 1:54 AM CDT	Special Weather Statement	OUN	Major	36 min
Apr 17, 2:22 AM CDT	Special Weather Statement	OUN	Dewey	23 min
Apr 17, 2:32 AM CDT	Special Weather Statement	OUN	Garfield	28 min
Apr 17, 2:53 AM CDT	Special Weather Statement	OUN	Dewey, Major	37 min
Apr 17, 3:02 AM CDT	Severe Thunderstorm Warning	OUN	Beckham, Greer, Harmon, Jackson	43 min
Apr 17, 3:33 AM CDT	Severe Thunderstorm Warning	OUN	Beckham, Custer, Greer, Harmon, Kiowa, Roger Mills and 1 more	42 min
Apr 17, 3:55 AM CDT	Special Weather Statement	OUN	Jackson	35 min
Apr 17, 4:13 AM CDT	Severe Thunderstorm Warning	OUN	Beckham, Custer, Dewey, Greer, Kiowa, Roger Mills and 1 more	47 min
Apr 17, 4:20 AM CDT	Areal Flood Advisory	OUN	Beckham, Custer, Dewey, Roger Mills, Washita	3 hr
Apr 17, 4:43 AM CDT	Special Weather Statement	OUN	Jackson	32 min
Apr 17, 5:03 AM CDT	Special Weather Statement	OUN	Washita	27 min
Apr 17, 5:17 AM CDT	Special Weather Statement	OUN	Jackson	28 min
Apr 17, 5:32 AM CDT	River Flood Warning	OUN	Custer, Roger Mills	20 hr
Apr 17, 5:34 AM CDT	Special Weather Statement	OUN	Caddo	26 min
Apr 17, 5:58 AM CDT	Special Weather Statement	OUN	Tillman	32 min
Apr 17, 6:09 AM CDT	Severe Thunderstorm Warning	OUN	Comanche, Kiowa	51 min
Apr 17, 6:59 AM CDT	Special Weather Statement	OUN	Comanche	31 min
Apr 17, 7:14 AM CDT	Special Weather Statement	OUN	Comanche	46 min
Apr 17, 8:36 AM CDT	Special Weather Statement	OUN	Grady	24 min
Apr 17, 8:37 AM CDT	Special Weather Statement	OUN	Harmon, Jackson, Kiowa, Tillman	38 min
Apr 17, 9:40 AM CDT	Special Weather Statement	OUN	Tillman	50 min
Apr 17, 9:53 AM CDT	Special Weather Statement	OUN	Harmon	37 min
Apr 17, 9:56 AM CDT	Severe Thunderstorm Warning	OUN	Jackson	36 min
Apr 17, 10:08 AM CDT	Special Weather Statement	OUN	Kiowa	37 min
Apr 17, 10:43 AM CDT	Special Weather Statement	OUN	Caddo	32 min
Apr 17, 10:47 AM CDT	Special Weather Statement	OUN	Greer, Jackson	28 min
Apr 17, 11:01 AM CDT	Severe Thunderstorm Warning	OUN	Caddo, Canadian, Grady	26 min
Apr 17, 4:50 PM CDT	Special Weather Statement	OUN	Woodward	25 min
Apr 17, 5:55 PM CDT	Special Weather Statement	OUN	Harper	35 min
Apr 17, 6:05 PM CDT	Special Weather Statement	OUN	Blaine	25 min
Apr 17, 9:05 AM CDT	Special Weather Statement	OUN	Foard	25 min
Apr 17, 9:18 AM CDT	Severe Thunderstorm Warning	OUN	Foard, Hardeman	42 min
Apr 17, 11:38 AM CDT	Special Weather Statement	OUN	Foard	52 min
Apr 17, 12:06 PM CDT	Special Weather Statement	OUN	Baylor, Foard, Hardeman, Knox, Wilbarger	24 min
Apr 17, 1:51 PM CDT	Special Weather Statement	OUN	Archer	24 min
Apr 17, 3:00 PM CDT	Special Weather Statement	OUN	Knox	30 min
Apr 17, 3:05 PM CDT	Special Weather Statement	OUN	Knox	25 min

Nearby

Severe Thunderstorm Warnings in Texas, 2015 Every severe thunderstorm warning in 2015

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.