Alert archive / Nebraska / Tornado Watches in 2007

Tornado Watch 226

May 4, 200728 counties in Nebraska; 19 counties in South Dakota

The Storm Prediction Center issued this tornado watch at May 4, 2007, 2:24 PM CDT for 28 counties in Nebraska; 19 counties in South Dakota. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued: May 4, 2007, 2:24 PM CDT (19:24 UTC)
Expired: May 4, 2007, 9:26 PM CDT
In force: 7 hr
Issued by: the Storm Prediction Center
Largest hail expected: 2.5 in
Strongest gust expected: 60 kt

All 47 counties

Antelope County, NE, Blaine County, NE, Boone County, NE, Boyd County, NE, Brown County, NE, Buffalo County, NE, Cedar County, NE, Custer County, NE, Dawson County, NE, Dixon County, NE, Garfield County, NE, Greeley County, NE, Holt County, NE, Howard County, NE, Keya Paha County, NE, Knox County, NE, Lincoln County, NE, Logan County, NE, Loup County, NE, Madison County, NE, Pierce County, NE, Rock County, NE, Sherman County, NE, Stanton County, NE, Thomas County, NE, Valley County, NE, Wayne County, NE, Wheeler County, NE, Aurora County, SD, Beadle County, SD, Bon Homme County, SD, Brule County, SD, Charles Mix County, SD, Clay County, SD, Davison County, SD, Douglas County, SD, Gregory County, SD, Hanson County, SD, Hutchinson County, SD, Jerauld County, SD, Kingsbury County, SD, McCook County, SD, Miner County, SD, Sanborn County, SD, Turner County, SD, Union County, SD, Yankton County, SD

The radar

The North Platte radar (KLNX), 159 km from the middle of the area, began a volume at 19:27 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: 20%
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

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

Issued	Product	Office	Counties	Lasted
May 4, 2:26 PM CDT	Severe Thunderstorm Warning	LBF	Custer	34 min
May 4, 2:39 PM CDT	Severe Thunderstorm Warning	LBF	Garfield	51 min
May 4, 3:19 PM CDT	Severe Thunderstorm Warning	LBF	Holt	41 min
May 4, 3:34 PM CDT	Tornado Warning	LBF	Holt	41 min
May 4, 4:06 PM CDT	Tornado Warning	LBF	Holt	24 min
May 4, 4:30 PM CDT	Severe Thunderstorm Warning	LBF	Holt	45 min
May 4, 4:59 PM CDT	Severe Thunderstorm Warning	FSD	Charles Mix	46 min
May 4, 5:16 PM CDT	Severe Thunderstorm Warning	LBF	Boyd, Holt	44 min
May 4, 5:23 PM CDT	Severe Thunderstorm Warning	OAX	Knox	37 min
May 4, 5:27 PM CDT	Severe Thunderstorm Warning	LBF	Boyd, Holt	23 min
May 4, 5:42 PM CDT	Severe Thunderstorm Warning	LBF	Brown, Cherry	48 min
May 4, 5:58 PM CDT	Severe Thunderstorm Warning	LBF	Boyd, Holt	47 min
May 4, 6:00 PM CDT	Severe Thunderstorm Warning	FSD	Bon Homme, Charles Mix	45 min
May 4, 6:15 PM CDT	Severe Thunderstorm Warning	FSD	Hutchinson	45 min
May 4, 6:17 PM CDT	Severe Thunderstorm Warning	FSD	Gregory	43 min
May 4, 6:31 PM CDT	Severe Thunderstorm Warning	LBF	Keya Paha	29 min
May 4, 6:51 PM CDT	Severe Thunderstorm Warning	FSD	Hanson, Hutchinson	39 min
May 4, 7:04 PM CDT	Severe Thunderstorm Warning	LBF	Boyd	22 min
May 4, 7:25 PM CDT	Severe Thunderstorm Warning	FSD	Hanson	35 min
May 4, 7:43 PM CDT	Tornado Warning	FSD	Hanson	32 min
May 4, 7:50 PM CDT	Tornado Warning	FSD	Hanson	25 min
May 4, 8:12 PM CDT	Severe Thunderstorm Warning	FSD	Lake, Miner	33 min
May 4, 8:14 PM CDT	Tornado Warning	FSD	Hanson	31 min
May 4, 9:04 PM CDT	Severe Thunderstorm Warning	FSD	Davison	26 min
May 4, 9:24 PM CDT	Severe Thunderstorm Warning	FSD	Davison, Sanborn	36 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

N. Platte/Lee Bi, NE (KLBF), launched 12:00Z, 7.4 hours before the alert went out and 216 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: 802 m above ground
0-6 km bulk shear: 52 kt
0-1 km storm-relative helicity: 56 m²/s²
0-3 km storm-relative helicity: 87 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
May 3, 7:34 PM CDT	Mesoscale Discussion	SPC	Banner, Cheyenne, Deuel, Kimball, Morrill, Scotts Bluff	26 min
May 3, 7:43 PM CDT	Tornado Watch	SPC	Banner, Box Butte, Cheyenne, Dawes, Deuel, Garden and 5 more	5 hr
May 3, 9:57 PM CDT	Mesoscale Discussion	SPC	Cheyenne, Deuel, Garden, Kimball, Morrill	93 min
May 4, 1:19 PM CDT	Mesoscale Discussion	SPC	Antelope, Boone, Boyd, Buffalo, Burt, Butler and 32 more	86 min
May 4, 5:07 PM CDT	Mesoscale Discussion	SPC	Chase, Dundy, Hayes, Hitchcock	83 min
May 4, 6:20 PM CDT	Mesoscale Discussion	SPC	Antelope, Blaine, Boone, Boyd, Cedar, Custer and 16 more	85 min
May 4, 6:36 PM CDT	Tornado Watch	SPC	Chase, Deuel, Dundy, Frontier, Hayes, Hitchcock and 3 more	7 hr

Nearby

Tornado Watches in Nebraska, 2007 Tornado Watches in South Dakota, 2007 Every tornado watch in 2007

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.