Alert archive / Oklahoma / Severe Thunderstorm Watches in 2011

Severe Thunderstorm Watch 869

October 22, 201152 counties in Oklahoma; 42 counties in Texas

The Storm Prediction Center issued this severe thunderstorm watch at Oct 22, 2011, 3:37 PM CDT for 52 counties in Oklahoma; 42 counties in Texas. It was in force for 14 hr.

The area

The outline as issued.

The facts

Issued: Oct 22, 2011, 3:37 PM CDT (20:37 UTC)
Expired: Oct 23, 2011, 6:00 AM CDT
In force: 14 hr
Issued by: the Storm Prediction Center
Largest hail expected: 2 in
Strongest gust expected: 60 kt

All 94 counties

Adair County, OK, Atoka County, OK, Bryan County, OK, Caddo County, OK, Canadian County, OK, Carter County, OK, Cherokee County, OK, Choctaw County, OK, Cleveland County, OK, Coal County, OK, Comanche County, OK, Cotton County, OK, Creek County, OK, Garfield County, OK, Garvin County, OK, Grady County, OK, Grant County, OK, Haskell County, OK, Hughes County, OK, Jefferson County, OK, Johnston County, OK, Kay County, OK, Kingfisher County, OK, Latimer County, OK, LeFlore County, OK, Lincoln County, OK, Logan County, OK, Love County, OK, Marshall County, OK, Mayes County, OK, McClain County, OK, McCurtain County, OK, McIntosh County, OK, Murray County, OK, Muskogee County, OK, Noble County, OK, Okfuskee County, OK, Oklahoma County, OK, Okmulgee County, OK, Osage County, OK, Pawnee County, OK, Payne County, OK, Pittsburg County, OK, Pontotoc County, OK, Pottawatomie County, OK, Pushmataha County, OK, Rogers County, OK, Seminole County, OK, Sequoyah County, OK, Stephens County, OK, Tulsa County, OK, Wagoner County, OK, Anderson County, TX, Bowie County, TX, Camp County, TX, Cass County, TX, Clay County, TX, Collin County, TX, Cooke County, TX, Dallas County, TX, Delta County, TX, Denton County, TX, Ellis County, TX, Fannin County, TX, Franklin County, TX, Freestone County, TX, Grayson County, TX, Gregg County, TX, Harrison County, TX, Henderson County, TX, Hill County, TX, Hopkins County, TX, Hunt County, TX, Jack County, TX, Johnson County, TX, Kaufman County, TX, Lamar County, TX, Leon County, TX, Limestone County, TX, Marion County, TX, Montague County, TX, Morris County, TX, Navarro County, TX, Palo Pinto County, TX, Parker County, TX, Rains County, TX, Red River County, TX, Rockwall County, TX, Tarrant County, TX, Titus County, TX, Upshur County, TX, Van Zandt County, TX, Wise County, TX, Wood County, TX

The radar

The Norman radar (KTLX), 106 km from the middle of the area, began a volume at 20:37 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: 10%
One or more EF2 to EF5 tornadoes: 2%
Ten or more severe wind reports: 40%
One or more gusts of 65 knots or more: 30%
Ten or more severe hail reports: 50%
One or more hailstones of 2 inches or more: 20%
Six or more combined severe hail and wind reports: 80%

Warnings issued inside it

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

Issued	Product	Office	Counties	Lasted
Oct 22, 4:31 PM CDT	Severe Thunderstorm Warning	OUN	Grant, Kay	59 min
Oct 22, 5:22 PM CDT	Severe Thunderstorm Warning	OUN	Lincoln	53 min
Oct 22, 5:28 PM CDT	Severe Thunderstorm Warning	TSA	Creek, Okfuskee	62 min
Oct 22, 5:29 PM CDT	Severe Thunderstorm Warning	OUN	Garfield, Grant, Kay, Noble	76 min
Oct 22, 5:31 PM CDT	Severe Thunderstorm Warning	TSA	Osage, Pawnee	59 min
Oct 22, 5:58 PM CDT	Severe Thunderstorm Warning	OUN	Canadian, Kingfisher	77 min
Oct 22, 6:09 PM CDT	Severe Thunderstorm Warning	TSA	Okfuskee	66 min
Oct 22, 6:11 PM CDT	Severe Thunderstorm Warning	OUN	Garvin, McClain, Pontotoc, Pottawatomie, Seminole	79 min
Oct 22, 6:27 PM CDT	Tornado Warning	TSA	Okfuskee	33 min
Oct 22, 6:32 PM CDT	Severe Thunderstorm Warning	TSA	Creek, Osage, Pawnee, Rogers, Tulsa	58 min
Oct 22, 6:34 PM CDT	Severe Thunderstorm Warning	OUN	Noble, Payne	71 min
Oct 22, 6:40 PM CDT	Severe Thunderstorm Warning	TSA	Creek, Okmulgee, Osage, Pawnee, Rogers, Tulsa and 1 more	65 min
Oct 22, 6:43 PM CDT	Severe Thunderstorm Warning	OUN	Hughes, Seminole	62 min
Oct 22, 6:46 PM CDT	Tornado Warning	TSA	Okfuskee	29 min
Oct 22, 6:59 PM CDT	Severe Thunderstorm Warning	OUN	Canadian, Cleveland, Grady, McClain, Oklahoma	76 min
Oct 22, 7:10 PM CDT	Severe Thunderstorm Warning	OUN	Lincoln	80 min
Oct 22, 7:10 PM CDT	Tornado Warning	TSA	Okfuskee	20 min
Oct 22, 7:14 PM CDT	Severe Thunderstorm Warning	TSA	McIntosh, Okfuskee, Okmulgee	61 min
Oct 22, 7:24 PM CDT	Severe Thunderstorm Warning	TSA	Creek, Okfuskee	36 min
Oct 22, 7:26 PM CDT	Severe Thunderstorm Warning	TSA	Cherokee, Mayes, Muskogee, Rogers, Tulsa, Wagoner	53 min
Oct 22, 7:31 PM CDT	Severe Thunderstorm Warning	OUN	Cleveland	74 min
Oct 22, 7:32 PM CDT	Severe Thunderstorm Warning	OUN	Logan, Oklahoma	48 min
Oct 22, 7:34 PM CDT	Severe Thunderstorm Warning	OUN	Coal, Hughes, Pontotoc, Seminole	86 min
Oct 22, 7:43 PM CDT	Severe Thunderstorm Warning	OUN	Cleveland, Grady, McClain	77 min
Oct 22, 8:02 PM CDT	Severe Thunderstorm Warning	OUN	Hughes, Pottawatomie, Seminole	58 min
Oct 22, 8:11 PM CDT	Severe Thunderstorm Warning	TSA	McIntosh, Okfuskee, Pittsburg	64 min
Oct 22, 8:39 PM CDT	Severe Thunderstorm Warning	OUN	Carter, Garvin, Grady, Murray, Stephens	81 min
Oct 22, 8:55 PM CDT	Severe Thunderstorm Warning	TSA	McIntosh, Pittsburg	65 min
Oct 22, 8:58 PM CDT	Severe Thunderstorm Warning	OUN	Atoka, Coal, Hughes, Pontotoc	77 min
Oct 22, 9:45 PM CDT	Severe Thunderstorm Warning	TSA	LeFlore	60 min
Oct 22, 9:55 PM CDT	Severe Thunderstorm Warning	OUN	Carter, Garvin, Jefferson, Love, Murray, Stephens	65 min
Oct 22, 9:59 PM CDT	Severe Thunderstorm Warning	OUN	Atoka, Bryan, Coal, Johnston, Marshall	76 min
Oct 22, 10:09 PM CDT	Tornado Warning	OUN	Carter, Jefferson, Stephens	38 min
Oct 22, 10:56 PM CDT	Severe Thunderstorm Warning	OUN	Jefferson	49 min
Oct 22, 11:14 PM CDT	Severe Thunderstorm Warning	FWD	Grayson	61 min
Oct 22, 11:16 PM CDT	Severe Thunderstorm Warning	FWD	Cooke, Montague	59 min
Oct 22, 11:30 PM CDT	Severe Thunderstorm Warning	OUN	Clay	60 min
Oct 23, 12:12 AM CDT	Severe Thunderstorm Warning	SHV	McCurtain	63 min
Oct 23, 12:24 AM CDT	Severe Thunderstorm Warning	FWD	Delta, Fannin, Hopkins, Hunt, Lamar, Rains	66 min
Oct 23, 12:24 AM CDT	Severe Thunderstorm Warning	SHV	Franklin, Red River, Titus	51 min
Oct 23, 12:29 AM CDT	Severe Thunderstorm Warning	FWD	Collin, Denton, Grayson	46 min
Oct 23, 12:33 AM CDT	Severe Thunderstorm Warning	SHV	McCurtain	23 min
Oct 23, 12:53 AM CDT	Severe Thunderstorm Warning	FWD	Cooke, Montague, Wise	37 min
Oct 23, 12:59 AM CDT	Severe Thunderstorm Warning	SHV	Bowie, Camp, Cass, Franklin, Harrison, Marion and 4 more	61 min
Oct 23, 1:11 AM CDT	Severe Thunderstorm Warning	FWD	Collin, Dallas, Denton, Rockwall	49 min
Oct 23, 1:20 AM CDT	Severe Thunderstorm Warning	FWD	Denton, Wise	40 min
Oct 23, 1:42 AM CDT	Severe Thunderstorm Warning	FWD	Tarrant	48 min
Oct 23, 1:52 AM CDT	Severe Thunderstorm Warning	FWD	Kaufman	38 min
Oct 23, 1:58 AM CDT	Severe Thunderstorm Warning	FWD	Dallas, Rockwall	47 min
Oct 23, 2:14 AM CDT	Severe Thunderstorm Warning	FWD	Ellis, Kaufman	46 min
Oct 23, 2:58 AM CDT	Severe Thunderstorm Warning	FWD	Henderson, Navarro	47 min
Oct 23, 3:00 AM CDT	Severe Thunderstorm Warning	FWD	Ellis, Kaufman	45 min
Oct 23, 3:18 AM CDT	Severe Thunderstorm Warning	FWD	Anderson, Henderson	42 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

Norman, OK (KOUN), launched 12:00Z, 8.6 hours before the alert went out and 100 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: 138 J/kg
Mixed-layer CIN: -205 J/kg
Mixed-layer LCL: 1045 m above ground
0-6 km bulk shear: 19 kt
0-1 km storm-relative helicity: 92 m²/s²
0-3 km storm-relative helicity: 121 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.6

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Oct 22, 1:49 PM CDT	Mesoscale Discussion	SPC	Atoka, Bryan, Canadian, Carter, Choctaw, Cleveland and 21 more	116 min

Nearby

Severe Thunderstorm Watches in Oklahoma, 2011 Severe Thunderstorm Watches in Texas, 2011 Every severe thunderstorm watch in 2011

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.