Alert archive / Nebraska / Severe Thunderstorm Watches in 2021

Severe Thunderstorm Watch 291

June 19, 202116 counties in Kansas; 18 counties in Nebraska

The Storm Prediction Center issued this severe thunderstorm watch at Jun 19, 2021, 9:43 PM CDT for 16 counties in Kansas; 18 counties in Nebraska. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued
Jun 19, 2021, 9:43 PM CDT (02:43 UTC)
Expired
Jun 20, 2021, 1:34 AM CDT
In force
4 hr
Issued by
the Storm Prediction Center
Largest hail expected
1.5 in
Strongest gust expected
70 kt
All 34 counties

Barton County, KS, Clay County, KS, Cloud County, KS, Ellsworth County, KS, Jewell County, KS, Lincoln County, KS, Mitchell County, KS, Ness County, KS, Osborne County, KS, Ottawa County, KS, Republic County, KS, Rush County, KS, Russell County, KS, Saline County, KS, Smith County, KS, Washington County, KS, Adams County, NE, Buffalo County, NE, Butler County, NE, Clay County, NE, Fillmore County, NE, Franklin County, NE, Hall County, NE, Hamilton County, NE, Jefferson County, NE, Kearney County, NE, Merrick County, NE, Nuckolls County, NE, Polk County, NE, Saline County, NE, Seward County, NE, Thayer County, NE, Webster County, NE, York County, NE

The radar

The Grand Island radar (KUEX), 36 km from the middle of the area, began a volume at 02:46 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
20%
One or more EF2 to EF5 tornadoes
2%
Ten or more severe wind reports
70%
One or more gusts of 65 knots or more
40%
Ten or more severe hail reports
40%
One or more hailstones of 2 inches or more
10%
Six or more combined severe hail and wind reports
90%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Jun 19, 10:03 PM CDTSevere Thunderstorm WarningGIDJewell, Phillips, Smith42 min
Jun 19, 10:09 PM CDTSevere Thunderstorm WarningGIDMitchell, Osborne, Rooks51 min
Jun 19, 10:13 PM CDTSevere Thunderstorm WarningICTRussell62 min
Jun 19, 10:45 PM CDTSevere Thunderstorm WarningGIDJewell, Smith45 min
Jun 19, 11:14 PM CDTSevere Thunderstorm WarningTOPCloud, Republic61 min
Jun 19, 11:28 PM CDTSevere Thunderstorm WarningGIDAdams, Clay, Fillmore, Nuckolls, Thayer, Webster47 min
Jun 20, 12:01 AM CDTSevere Thunderstorm WarningOAXJefferson, Saline, Seward44 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 00:00Z, 2.7 hours before the alert went out and 212 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 00:00Z on 2021-06-20Temperature 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 00:00Z on 2021-06-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 113 square meters per square second.193958Sfc1 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
2727 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
113 m²/s²
0-3 km storm-relative helicity
207 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

910 
WWUS20 KWNS 200241
SEL1  
SPC WW 200241
KSZ000-NEZ000-200900-

URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 291
NWS Storm Prediction Center Norman OK
940 PM CDT Sat Jun 19 2021

The NWS Storm Prediction Center has issued a

* Severe Thunderstorm Watch for portions of 
  North-Central Kansas
  South-Central/Southeast Nebraska

* Effective this Saturday night and Sunday morning from 940 PM
  until 400 AM CDT.

* Primary threats include...
  Scattered damaging winds likely with isolated significant gusts
    to 80 mph possible
  Scattered large hail events to 1.5 inches in diameter possible
  A tornado or two possible

SUMMARY...A well-organized and intense cluster of storms will
continue eastward across northern Kansas and southern Nebraska late
this evening into the overnight. Damaging winds, with wind gusts
potentially in excess of 75 mph, can be expected. Isolated large
hail is possible as well, and a brief tornado could occur with
circulations embedded within the convective line.

The severe thunderstorm watch area is approximately along and 90
statute miles north and south of a line from 65 miles northwest of
Russell KS to 55 miles northeast of Concordia KS. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU1).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A Severe Thunderstorm Watch means conditions are
favorable for severe thunderstorms in and close to the watch area.
Persons in these areas should be on the lookout for threatening
weather conditions and listen for later statements and possible
warnings. Severe thunderstorms can and occasionally do produce
tornadoes.

&&

OTHER WATCH INFORMATION...CONTINUE...WW 287...WW 286...WW
288...WW 289...WW 290...

AVIATION...A few severe thunderstorms with hail surface and aloft to
1.5 inches. Extreme turbulence and surface wind gusts to 70 knots. A
few cumulonimbi with maximum tops to 600. Mean storm motion vector
26035.

...Guyer

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 19, 7:22 PM CDTMesoscale DiscussionSPCCheyenne, Decatur, Logan, Rawlins, Sherman, Thomas and 1 more113 min
Jun 19, 9:00 PM CDTMesoscale DiscussionSPCCloud, Decatur, Graham, Jewell, Mitchell, Norton and 7 more60 min
Jun 19, 11:09 PM CDTMesoscale DiscussionSPCBrown, Clay, Cloud, Jewell, Marshall, Mitchell and 7 more96 min
Jun 19, 11:59 PM CDTSevere Thunderstorm WatchSPCBrown, Doniphan, Marshall, Nemaha4 hr
Jun 20, 2:02 PM CDTMesoscale DiscussionSPCAtchison, Brown, Doniphan, Douglas, Jackson, Jefferson and 3 more118 min
Jun 20, 4:01 PM CDTSevere Thunderstorm WatchSPCAtchison, Doniphan, Johnson, Leavenworth, Wyandotte7 hr
Jun 20, 6:56 PM CDTMesoscale DiscussionSPCAtchison, Leavenworth, Wyandotte2 hr

Nearby

Severe Thunderstorm Watches in Nebraska, 2021Severe Thunderstorm Watches in Kansas, 2021Every severe thunderstorm watch in 2021

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.