Alert archive / Texas / Tornado Watches in 2010

Tornado Watch 188

May 18, 201013 counties in Oklahoma; 20 counties in Texas

The Storm Prediction Center issued this tornado watch at May 18, 2010, 10:49 PM CDT for 13 counties in Oklahoma; 20 counties in Texas. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued: May 18, 2010, 10:49 PM CDT (03:49 UTC)
Expired: May 19, 2010, 3:43 AM CDT
In force: 5 hr
Issued by: the Storm Prediction Center
Largest hail expected: 2 in
Strongest gust expected: 60 kt

All 33 counties

Beaver County, OK, Beckham County, OK, Cimarron County, OK, Custer County, OK, Dewey County, OK, Ellis County, OK, Harper County, OK, Major County, OK, Roger Mills County, OK, Texas County, OK, Washita County, OK, Woods County, OK, Woodward County, OK, Armstrong County, TX, Carson County, TX, Collingsworth County, TX, Dallam County, TX, Deaf Smith County, TX, Donley County, TX, Gray County, TX, Hansford County, TX, Hartley County, TX, Hemphill County, TX, Hutchinson County, TX, Lipscomb County, TX, Moore County, TX, Ochiltree County, TX, Oldham County, TX, Potter County, TX, Randall County, TX, Roberts County, TX, Sherman County, TX, Wheeler County, TX

The radar

The Amarillo radar (KAMA), 107 km from the middle of the area, began a volume at 03:51 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.

What SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes: 40%
One or more EF2 to EF5 tornadoes: 20%
Ten or more severe wind reports: 30%
One or more gusts of 65 knots or more: 30%
Ten or more severe hail reports: 60%
One or more hailstones of 2 inches or more: 30%
Six or more combined severe hail and wind reports: 70%

Warnings issued inside it

20 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

Issued	Product	Office	Counties	Lasted
May 18, 11:39 PM CDT	Tornado Warning	OUN	Ellis, Roger Mills	36 min
May 18, 11:40 PM CDT	Tornado Warning	AMA	Hansford, Ochiltree, Sherman	65 min
May 18, 11:42 PM CDT	Severe Thunderstorm Warning	AMA	Hemphill, Lipscomb	80 min
May 19, 12:14 AM CDT	Severe Thunderstorm Warning	OUN	Ellis, Roger Mills	61 min
May 19, 12:48 AM CDT	Severe Thunderstorm Warning	AMA	Hansford, Hutchinson, Moore, Ochiltree, Sherman	87 min
May 19, 12:49 AM CDT	Tornado Warning	OUN	Ellis, Roger Mills	41 min
May 19, 12:51 AM CDT	Severe Thunderstorm Warning	AMA	Hansford, Lipscomb, Ochiltree, Sherman	54 min
May 19, 1:27 AM CDT	Tornado Warning	OUN	Ellis, Roger Mills	48 min
May 19, 1:34 AM CDT	Severe Thunderstorm Warning	AMA	Hansford, Hutchinson, Ochiltree, Roberts	86 min
May 19, 1:54 AM CDT	Severe Thunderstorm Warning	AMA	Cimarron	66 min
May 19, 2:02 AM CDT	Tornado Warning	AMA	Hansford, Hutchinson, Moore, Sherman	28 min
May 19, 2:07 AM CDT	Tornado Warning	OUN	Custer, Dewey, Ellis, Roger Mills	38 min
May 19, 2:24 AM CDT	Tornado Warning	AMA	Hansford, Hutchinson	36 min
May 19, 2:31 AM CDT	Severe Thunderstorm Warning	AMA	Beaver	59 min
May 19, 2:43 AM CDT	Severe Thunderstorm Warning	OUN	Dewey	62 min
May 19, 2:51 AM CDT	Severe Thunderstorm Warning	AMA	Ochiltree	54 min
May 19, 2:53 AM CDT	Tornado Warning	AMA	Hansford, Hutchinson, Ochiltree, Roberts	37 min
May 19, 3:22 AM CDT	Tornado Warning	AMA	Ochiltree, Roberts	38 min
May 19, 3:30 AM CDT	Severe Thunderstorm Warning	AMA	Lipscomb, Ochiltree	60 min
May 19, 3:39 AM CDT	Severe Thunderstorm Warning	OUN	Blaine, Dewey, Major	66 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Amarillo Airport, TX (KAMA), launched 00:00Z, 3.8 hours before the alert went out and 107 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: 1657 J/kg
Mixed-layer CIN: -21 J/kg
Mixed-layer LCL: 1095 m above ground
0-6 km bulk shear: 67 kt
0-1 km storm-relative helicity: 177 m²/s²
0-3 km storm-relative helicity: 306 m²/s²
Significant tornado parameter: 2.8
Supercell composite: 19.0

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 18, 7:41 PM CDT	Mesoscale Discussion	SPC	Cimarron, Texas	64 min
May 18, 9:27 PM CDT	Mesoscale Discussion	SPC	Beckham, Custer, Dewey, Ellis, Greer, Harmon and 6 more	93 min
May 18, 10:36 PM CDT	Mesoscale Discussion	SPC	Beaver, Beckham, Dewey, Ellis, Harper, Roger Mills and 2 more	54 min
May 19, 1:24 AM CDT	Mesoscale Discussion	SPC	Beaver, Beckham, Cimarron, Custer, Dewey, Ellis and 6 more	66 min
May 19, 3:23 AM CDT	Mesoscale Discussion	SPC	Alfalfa, Blaine, Creek, Custer, Dewey, Ellis and 13 more	67 min
May 19, 3:42 AM CDT	Severe Thunderstorm Watch	SPC	Alfalfa, Beaver, Blaine, Creek, Custer, Dewey and 25 more	6 hr
May 19, 5:32 AM CDT	Mesoscale Discussion	SPC	Alfalfa, Creek, Dewey, Garfield, Grant, Kay and 7 more	58 min
May 19, 1:22 PM CDT	Mesoscale Discussion	SPC	Atoka, Beckham, Blaine, Bryan, Caddo, Canadian and 43 more	113 min
May 19, 2:06 PM CDT	Tornado Watch PDS	SPC	Atoka, Beckham, Blaine, Bryan, Caddo, Canadian and 50 more	8 hr
May 19, 3:20 PM CDT	Mesoscale Discussion	SPC	Atoka, Beckham, Blaine, Bryan, Caddo, Canadian and 43 more	85 min
May 19, 5:30 PM CDT	Mesoscale Discussion	SPC	Atoka, Caddo, Canadian, Cleveland, Coal, Comanche and 31 more	60 min

Nearby

Tornado Watches in Texas, 2010 Tornado Watches in Oklahoma, 2010 Every tornado watch in 2010

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.