Alert archive / Nebraska / Tornado Watches in 2013

Tornado Watch 538

October 3, 20135 counties in Iowa; 17 counties in Nebraska

The Storm Prediction Center issued this tornado watch at Oct 3, 2013, 9:13 PM CDT for 5 counties in Iowa; 17 counties in Nebraska. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued: Oct 3, 2013, 9:13 PM CDT (02:13 UTC)
Expired: Oct 4, 2013, 2:20 AM CDT
In force: 5 hr
Issued by: the Storm Prediction Center
Largest hail expected: 3 in
Strongest gust expected: 60 kt

All 22 counties

Fremont County, IA, Mills County, IA, Montgomery County, IA, Page County, IA, Pottawattamie County, IA, Butler County, NE, Cass County, NE, Douglas County, NE, Fillmore County, NE, Gage County, NE, Jefferson County, NE, Johnson County, NE, Lancaster County, NE, Nemaha County, NE, Nuckolls County, NE, Otoe County, NE, Saline County, NE, Sarpy County, NE, Saunders County, NE, Seward County, NE, Thayer County, NE, York County, NE

The radar

The Omaha radar (KOAX), 55 km from the middle of the area, began a volume at 02:13 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: 30%
Ten or more severe wind reports: 30%
One or more gusts of 65 knots or more: 10%
Ten or more severe hail reports: 70%
One or more hailstones of 2 inches or more: 40%
Six or more combined severe hail and wind reports: 95%

Warnings issued inside it

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

Issued	Product	Office	Counties	Lasted
Oct 3, 9:19 PM CDT	Severe Thunderstorm Warning	OAX	Saline	26 min
Oct 3, 9:23 PM CDT	Tornado Warning	GID	Fillmore	37 min
Oct 3, 9:23 PM CDT	Severe Thunderstorm Warning	OAX	Lancaster	52 min
Oct 3, 9:42 PM CDT	Tornado Warning	OAX	Saline	48 min
Oct 3, 9:53 PM CDT	Severe Thunderstorm Warning	OAX	Saline	52 min
Oct 3, 10:06 PM CDT	Tornado Warning	OAX	Lancaster	24 min
Oct 3, 10:15 PM CDT	Severe Thunderstorm Warning	OAX	Lancaster, Otoe	30 min
Oct 3, 10:26 PM CDT	Tornado Warning Tornado observed	OAX	Lancaster, Otoe	34 min
Oct 3, 10:28 PM CDT	Tornado Warning	OAX	Saline	32 min
Oct 3, 10:40 PM CDT	Tornado Warning Tornado observed	OAX	Cass, Otoe	35 min
Oct 3, 10:45 PM CDT	Flash Flood Warning	OAX	Lancaster, Saline, Seward	6 hr
Oct 3, 10:56 PM CDT	Severe Thunderstorm Warning	OAX	Gage, Lancaster, Saline	34 min
Oct 3, 11:08 PM CDT	Tornado Warning	OAX	Cass	37 min
Oct 3, 11:25 PM CDT	Severe Thunderstorm Warning	OAX	Gage, Johnson, Lancaster, Otoe	35 min
Oct 3, 11:30 PM CDT	Severe Thunderstorm Warning	OAX	Mills	30 min
Oct 3, 11:53 PM CDT	Severe Thunderstorm Warning	OAX	Mills, Pottawattamie	22 min
Oct 4, 12:14 AM CDT	Severe Thunderstorm Warning	OAX	Mills, Montgomery, Pottawattamie	46 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

Omaha, NE (KOAX), launched 00:00Z, 2.2 hours before the alert went out and 55 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: 545 J/kg
Mixed-layer CIN: -94 J/kg
Mixed-layer LCL: 1097 m above ground
0-6 km bulk shear: 42 kt
0-1 km storm-relative helicity: 136 m²/s²
0-3 km storm-relative helicity: 349 m²/s²
Significant tornado parameter: 0.4
Supercell composite: 6.8

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Oct 3, 7:32 PM CDT	Mesoscale Discussion	SPC	Adair, Adams, Appanoose, Cass, Clarke, Dallas and 23 more	2 hr
Oct 3, 8:16 PM CDT	Severe Thunderstorm Watch	SPC	Adair, Adams, Appanoose, Audubon, Benton, Black Hawk and 49 more	9 hr
Oct 3, 11:42 PM CDT	Mesoscale Discussion	SPC	Adair, Adams, Appanoose, Audubon, Benton, Boone and 41 more	93 min
Oct 4, 2:06 AM CDT	Mesoscale Discussion	SPC	Adair, Adams, Appanoose, Audubon, Benton, Black Hawk and 70 more	84 min
Oct 4, 4:35 AM CDT	Mesoscale Discussion	SPC	Benton, Cedar, Clinton, Jackson, Jones, Linn	85 min
Oct 4, 9:03 AM CDT	Mesoscale Discussion	SPC	Appanoose, Cedar, Clinton, Davis, Decatur, Des Moines and 15 more	87 min
Oct 4, 1:28 PM CDT	Mesoscale Discussion	SPC	Adair, Adams, Appanoose, Audubon, Boone, Calhoun and 36 more	2 hr
Oct 4, 2:38 PM CDT	Tornado Watch	SPC	Buena Vista, Cherokee, Clay, Dickinson, Fremont, Harrison and 12 more	7 hr
Oct 4, 5:20 PM CDT	Mesoscale Discussion	SPC	Adair, Adams, Audubon, Buena Vista, Carroll, Cass and 20 more	85 min
Oct 4, 6:42 PM CDT	Tornado Watch	SPC	Adair, Adams, Audubon, Boone, Calhoun, Carroll and 29 more	5 hr

Nearby

Tornado Watches in Nebraska, 2013 Tornado Watches in Iowa, 2013 Every tornado watch in 2013

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.