Alert archive / Nebraska / Severe Thunderstorm Watches in 2021

Severe Thunderstorm Watch 292

June 19, 20214 states

The Storm Prediction Center issued this severe thunderstorm watch at Jun 19, 2021, 11:59 PM CDT for 4 states. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued
Jun 19, 2021, 11:59 PM CDT (04:59 UTC)
Expired
Jun 20, 2021, 4:21 AM CDT
In force
4 hr
Issued by
the Storm Prediction Center
Largest hail expected
1.5 in
Strongest gust expected
60 kt
All 33 counties

Adams County, IA, Audubon County, IA, Cass County, IA, Fremont County, IA, Harrison County, IA, Mills County, IA, Montgomery County, IA, Page County, IA, Pottawattamie County, IA, Shelby County, IA, Taylor County, IA, Brown County, KS, Doniphan County, KS, Marshall County, KS, Nemaha County, KS, Andrew County, MO, Atchison County, MO, Gentry County, MO, Holt County, MO, Nodaway County, MO, Worth County, MO, Cass County, NE, Douglas County, NE, Gage County, NE, Johnson County, NE, Lancaster County, NE, Nemaha County, NE, Otoe County, NE, Pawnee County, NE, Richardson County, NE, Sarpy County, NE, Saunders County, NE, Washington County, NE

The radar

The Omaha radar (KOAX), 65 km from the middle of the area, began a volume at 05:00 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
50%
One or more gusts of 65 knots or more
20%
Ten or more severe hail reports
30%
One or more hailstones of 2 inches or more
10%
Six or more combined severe hail and wind reports
80%

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, 5.0 hours before the alert went out and 65 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, Omaha, 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, Omaha, NE at 00:00Z on 2021-06-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 23 square meters per square second.19395878Sfc1 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
2439 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
23 m²/s²
0-3 km storm-relative helicity
69 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

076 
WWUS20 KWNS 200457
SEL2  
SPC WW 200457
IAZ000-KSZ000-MOZ000-NEZ000-201000-

URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 292
NWS Storm Prediction Center Norman OK
1155 PM CDT Sat Jun 19 2021

The NWS Storm Prediction Center has issued a

* Severe Thunderstorm Watch for portions of 
  Southwest Iowa
  Northeast Kansas
  Northwest Missouri
  Southeast Nebraska

* Effective this Saturday night and Sunday morning from 1155 PM
  until 500 AM CDT.

* Primary threats include...
  Scattered damaging wind gusts to 70 mph possible
  Isolated large hail events to 1.5 inches in diameter possible
  A tornado or two possible

SUMMARY...A well-organized cluster of storms will continue
east-northeastward across the region overnight with the continued
potential for damaging winds and some severe hail.

The severe thunderstorm watch area is approximately along and 70
statute miles north and south of a line from 10 miles north
northwest of Beatrice NE to 55 miles east northeast of Shenandoah
IA. For a complete depiction of the watch see the associated watch
outline update (WOUS64 KWNS WOU2).

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 289...WW 291...

AVIATION...A few severe thunderstorms with hail surface and aloft to
1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A
few cumulonimbi with maximum tops to 600. Mean storm motion vector
24040.

...Guyer

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 19, 11:09 PM CDTMesoscale DiscussionSPCAdair, Adams, Audubon, Cass, Fremont, Guthrie and 10 more96 min
Jun 20, 3:37 AM CDTMesoscale DiscussionSPCAdair, Adams, Appanoose, Audubon, Cass, Clarke and 12 more113 min
Jun 20, 10:57 AM CDTMesoscale DiscussionSPCDes Moines, Henry, Lee, Louisa, Scott2 hr
Jun 20, 1:10 PM CDTMesoscale DiscussionSPCBoone, Butler, Calhoun, Cerro Gordo, Emmet, Floyd and 17 more95 min
Jun 20, 1:42 PM CDTSevere Thunderstorm WatchSPCAllamakee, Black Hawk, Bremer, Butler, Calhoun, Cerro Gordo and 23 more7 hr
Jun 20, 2:02 PM CDTMesoscale DiscussionSPCAdair, Adams, Appanoose, Boone, Cass, Clarke and 22 more118 min
Jun 20, 4:01 PM CDTSevere Thunderstorm WatchSPCAppanoose, Benton, Boone, Buchanan, Cedar, Clarke and 35 more7 hr
Jun 20, 5:22 PM CDTMesoscale DiscussionSPCAllamakee, Black Hawk, Bremer, Buchanan, Butler, Chickasaw and 9 more113 min
Jun 20, 6:56 PM CDTMesoscale DiscussionSPCAppanoose, Clarke, Davis, Decatur, Des Moines, Henry and 15 more2 hr
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, 9:43 PM CDTSevere Thunderstorm WatchSPCBarton, Clay, Cloud, Ellsworth, Jewell, Lincoln and 10 more4 hr
Jun 19, 9:49 PM CDTMesoscale DiscussionSPCAudrain, Chariton, Lincoln, Macon, Monroe, Montgomery and 7 more56 min

Nearby

Severe Thunderstorm Watches in Nebraska, 2021Severe Thunderstorm Watches in Iowa, 2021Severe Thunderstorm Watches in Missouri, 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.