Alert archive / Nebraska / Severe Thunderstorm Watches in 2017

Severe Thunderstorm Watch 134

April 9, 201718 counties in Nebraska

The Storm Prediction Center issued this severe thunderstorm watch at Apr 9, 2017, 5:44 PM CDT for 18 counties in Nebraska. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued
Apr 9, 2017, 5:44 PM CDT (22:44 UTC)
Expired
Apr 9, 2017, 8:34 PM CDT
In force
3 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
70 kt

Counties Adams County, NE, Buffalo County, NE, Clay County, NE, Dawson County, NE, Fillmore County, NE, Franklin County, NE, Hall County, NE, Hamilton County, NE, Harlan County, NE, Howard County, NE, Kearney County, NE, Merrick County, NE, Nance County, NE, Nuckolls County, NE, Phelps County, NE, Sherman County, NE, Thayer County, NE, Webster County, NE

The radar

The Grand Island radar (KUEX), 65 km from the middle of the area, began a volume at 22:45 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
30%
One or more gusts of 65 knots or more
30%
Ten or more severe hail reports
30%
One or more hailstones of 2 inches or more
30%
Six or more combined severe hail and wind reports
60%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Apr 9, 6:04 PM CDTSevere Thunderstorm WarningGIDBuffalo, Kearney56 min
Apr 9, 6:32 PM CDTSevere Thunderstorm WarningGIDAdams, Franklin, Kearney, Webster58 min
Apr 9, 7:23 PM CDTSevere Thunderstorm WarningGIDAdams, Clay, Nuckolls, Webster39 min
Apr 9, 7:52 PM CDTSevere Thunderstorm WarningGIDFillmore, Thayer42 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, 10.7 hours before the alert went out and 146 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-pSkew-T log-p diagram, N. Platte/Lee Bi, NE at 12:00Z on 2017-04-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, N. Platte/Lee Bi, NE at 12:00Z on 2017-04-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 266 square meters per square second.1939587897117Sfc1 km3 km6 km9 kmRMLM
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
1407 m above ground
0-6 km bulk shear
66 kt
0-1 km storm-relative helicity
266 m²/s²
0-3 km storm-relative helicity
305 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.

IssuedProductOfficeCountiesLasted
Apr 9, 2:20 PM CDTMesoscale DiscussionSPCAdams, Arthur, Blaine, Buffalo, Chase, Custer and 27 more2 hr
Apr 9, 5:35 PM CDTMesoscale DiscussionSPCAdams, Buffalo, Clay, Dawson, Fillmore, Franklin and 8 more25 min

Nearby

Severe Thunderstorm Watches in Nebraska, 2017Every severe thunderstorm watch in 2017

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.