Alert archive / Oklahoma / Tornado Watches in 2008

Tornado Watch 180

April 9, 200817 counties in Oklahoma

The Storm Prediction Center issued this tornado watch at Apr 9, 2008, 5:38 PM CDT for 17 counties in Oklahoma. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued: Apr 9, 2008, 5:38 PM CDT (22:38 UTC)
Expired: Apr 9, 2008, 11:00 PM CDT
In force: 5 hr
Issued by: the Storm Prediction Center
Largest hail expected: 2 in
Strongest gust expected: 60 kt

Counties Adair County, OK, Cherokee County, OK, Delaware County, OK, Haskell County, OK, Hughes County, OK, Latimer County, OK, LeFlore County, OK, Mayes County, OK, McIntosh County, OK, Muskogee County, OK, Okfuskee County, OK, Okmulgee County, OK, Rogers County, OK, Seminole County, OK, Sequoyah County, OK, Tulsa County, OK, Wagoner County, OK

The radar

The Tulsa radar (KINX), 72 km from the middle of the area, began a volume at 22:41 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: 50%
One or more gusts of 65 knots or more: 30%
Ten or more severe hail reports: 40%
One or more hailstones of 2 inches or more: 30%
Six or more combined severe hail and wind reports: 80%

Warnings issued inside it

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

Issued	Product	Office	Counties	Lasted
Apr 9, 5:56 PM CDT	Severe Thunderstorm Warning	TSA	McIntosh, Okfuskee, Pittsburg	64 min
Apr 9, 6:09 PM CDT	Flash Flood Warning	OUN	Seminole	3 hr
Apr 9, 6:16 PM CDT	Severe Thunderstorm Warning	OUN	Hughes, Seminole	44 min
Apr 9, 6:17 PM CDT	Severe Thunderstorm Warning	OUN	Hughes	28 min
Apr 9, 6:23 PM CDT	Flash Flood Warning	OUN	Hughes	3 hr
Apr 9, 6:28 PM CDT	Flash Flood Warning	TSA	McIntosh, Okfuskee, Okmulgee	6 hr
Apr 9, 6:31 PM CDT	Severe Thunderstorm Warning	OUN	Pontotoc, Seminole	44 min
Apr 9, 6:43 PM CDT	Tornado Warning	TSA	Haskell, McIntosh, Muskogee, Pittsburg	47 min
Apr 9, 6:51 PM CDT	Flash Flood Warning	TSA	Creek, Muskogee, Okmulgee, Tulsa, Wagoner	6 hr
Apr 9, 6:53 PM CDT	Tornado Warning	OUN	Hughes, Pontotoc	37 min
Apr 9, 7:17 PM CDT	Tornado Warning	TSA	Cherokee, Muskogee, Sequoyah	43 min
Apr 9, 7:30 PM CDT	Tornado Warning	TSA	Haskell, LeFlore, Muskogee, Sequoyah	45 min
Apr 9, 8:03 PM CDT	Severe Thunderstorm Warning	TSA	Adair, Cherokee, Sequoyah	27 min
Apr 9, 8:08 PM CDT	Tornado Warning	TSA	Haskell, Latimer, Pittsburg	67 min
Apr 9, 8:16 PM CDT	Tornado Warning	TSA	LeFlore, Sequoyah	44 min
Apr 9, 8:24 PM CDT	Flash Flood Warning	TSA	Adair, Cherokee, Haskell, Muskogee, Sequoyah, Wagoner	4 hr
Apr 9, 8:29 PM CDT	Tornado Warning	TSA	LeFlore	61 min
Apr 9, 8:53 PM CDT	Tornado Warning	TSA	Haskell, Latimer, LeFlore	67 min
Apr 9, 9:04 PM CDT	Severe Thunderstorm Warning	TSA	Latimer	29 min
Apr 9, 9:35 PM CDT	Flash Flood Warning	TSA	Haskell, Latimer, LeFlore	5 hr
Apr 9, 10:02 PM CDT	Severe Thunderstorm Warning	TSA	LeFlore, Sequoyah	58 min
Apr 9, 10:07 PM CDT	Severe Thunderstorm Warning	TSA	Latimer, LeFlore, Pushmataha	53 min
Apr 9, 10:09 PM CDT	Tornado Warning	TSA	LeFlore, Sequoyah	51 min
Apr 9, 10:22 PM CDT	Tornado Warning	TSA	LeFlore	38 min
Apr 9, 10:38 PM CDT	Flash Flood Warning	TSA	Delaware, Mayes	8 hr
Apr 9, 10:51 PM CDT	Severe Thunderstorm Warning	TSA	LeFlore	44 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, 10.6 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1422 m above ground
0-6 km bulk shear: 57 kt
0-1 km storm-relative helicity: 169 m²/s²
0-3 km storm-relative helicity: 338 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 8, 10:36 PM CDT	Mesoscale Discussion	SPC	McCurtain	84 min
Apr 8, 11:51 PM CDT	Severe Thunderstorm Watch	SPC	McCurtain	5 hr
Apr 9, 3:29 AM CDT	Mesoscale Discussion	SPC	McCurtain	61 min
Apr 9, 9:06 AM CDT	Mesoscale Discussion	SPC	Beckham, Blaine, Caddo, Comanche, Cotton, Custer and 9 more	54 min
Apr 9, 9:35 AM CDT	Severe Thunderstorm Watch	SPC	Beckham, Caddo, Comanche, Cotton, Custer, Grady and 9 more	6 hr
Apr 9, 12:24 PM CDT	Mesoscale Discussion	SPC	Atoka, Beckham, Blaine, Bryan, Caddo, Canadian and 29 more	66 min
Apr 9, 3:07 PM CDT	Mesoscale Discussion	SPC	Blaine, Caddo, Canadian, Cleveland, Comanche, Cotton and 25 more	53 min
Apr 9, 3:33 PM CDT	Mesoscale Discussion	SPC	Atoka, Bryan, Carter, Choctaw, Coal, Johnston and 5 more	27 min
Apr 9, 3:48 PM CDT	Tornado Watch PDS	SPC	Atoka, Bryan, Carter, Choctaw, Coal, Johnston and 6 more	7 hr
Apr 9, 6:12 PM CDT	Mesoscale Discussion	SPC	Jackson	63 min
Apr 9, 6:55 PM CDT	Severe Thunderstorm Watch	SPC	Caddo, Canadian, Cleveland, Comanche, Cotton, Garvin and 15 more	8 hr

Nearby

Tornado Watches in Oklahoma, 2008 Every tornado watch in 2008

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.