Alert archive / Nebraska / Severe Thunderstorm Watches in 2021
Severe Thunderstorm Watch 195
The Storm Prediction Center issued this severe thunderstorm watch at May 22, 2021, 3:55 PM CDT for 4 counties in Kansas; 17 counties in Nebraska. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- May 22, 2021, 3:55 PM CDT (20:55 UTC)
- Expired
- May 22, 2021, 9:12 PM CDT
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
All 21 counties
Cheyenne County, KS, Rawlins County, KS, Sherman County, KS, Thomas County, KS, Arthur County, NE, Chase County, NE, Cheyenne County, NE, Deuel County, NE, Dundy County, NE, Frontier County, NE, Garden County, NE, Grant County, NE, Hayes County, NE, Hitchcock County, NE, Hooker County, NE, Keith County, NE, Kimball County, NE, Lincoln County, NE, McPherson County, NE, Morrill County, NE, Perkins County, NE
The radar
The North Platte radar (KLNX), 136 km from the middle of the area, began a volume at 20:54 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
- 5%
- Ten or more severe wind reports
- 30%
- One or more gusts of 65 knots or more
- 10%
- Ten or more severe hail reports
- 40%
- One or more hailstones of 2 inches or more
- 30%
- Six or more combined severe hail and wind reports
- 70%
Warnings issued inside it
3 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 22, 4:09 PM CDT | Severe Thunderstorm Warning | LBF | Deuel, Garden, Keith | 51 min |
| May 22, 4:13 PM CDT | Severe Thunderstorm Warning | GLD | Rawlins | 32 min |
| May 22, 5:31 PM CDT | Flash Flood Warning | LBF | Frontier | 3 hr |
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, 8.9 hours before the alert went out and 68 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.
- Mixed-layer CAPE
- 308 J/kg
- Mixed-layer CIN
- -258 J/kg
- Mixed-layer LCL
- 550 m above ground
- 0-6 km bulk shear
- 44 kt
- 0-1 km storm-relative helicity
- 246 m²/s²
- 0-3 km storm-relative helicity
- 264 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
131
WWUS20 KWNS 222052
SEL5
SPC WW 222052
KSZ000-NEZ000-230400-
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 195
NWS Storm Prediction Center Norman OK
255 PM MDT Sat May 22 2021
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Northwest Kansas
Southwest Nebraska
* Effective this Saturday afternoon and evening from 255 PM until
1000 PM MDT.
* Primary threats include...
Scattered large hail and isolated very large hail events to 2
inches in diameter possible
Isolated damaging wind gusts to 70 mph possible
A tornado or two possible
SUMMARY...Strong to severe thunderstorms will continue to develop
generally northeastward across the region, especially in vicinity of
a front that extends from northeast Colorado into southwest Nebraska
including areas near/north of Ogallala. Large hail and damaging
winds are possible, and a tornado risk may also exist, especially
near the aforementioned boundary near Ogallala.
The severe thunderstorm watch area is approximately along and 55
statute miles east and west of a line from 90 miles northwest of
North Platte NE to 40 miles east southeast of Goodland KS. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU5).
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 193...WW 194...
AVIATION...A few severe thunderstorms with hail surface and aloft to
2 inches. Extreme turbulence and surface wind gusts to 60 knots. A
few cumulonimbi with maximum tops to 500. Mean storm motion vector
22025.
...GuyerSPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 21, 7:30 PM CDT | Mesoscale Discussion | SPC | Cheyenne, Elbert, Kit Carson, Lincoln, Logan, Morgan and 4 more | 90 min |
| May 22, 11:51 AM CDT | Mesoscale Discussion | SPC | Adams, Arapahoe, Crowley, Denver, Douglas, Elbert and 8 more | 114 min |
| May 22, 1:20 PM CDT | Tornado Watch | SPC | Adams, Arapahoe, Bent, Cheyenne, Crowley, Denver and 17 more | 8 hr |
| May 22, 2:34 PM CDT | Mesoscale Discussion | SPC | Phillips, Sedgwick, Washington | 116 min |
| May 22, 5:51 PM CDT | Mesoscale Discussion | SPC | Bent, Cheyenne, Crowley, Elbert, Kiowa, Kit Carson and 10 more | 114 min |
| May 22, 6:31 PM CDT | Mesoscale Discussion | SPC | Phillips, Sedgwick | 119 min |
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.