Alert archive / Nebraska / Mesoscale Discussions in 2021
Mesoscale Discussion 719
The Storm Prediction Center issued this mesoscale discussion at May 23, 2021, 9:56 PM CDT for 8 counties in Kansas; 13 counties in Nebraska; Tripp County, South Dakota. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- May 23, 2021, 9:56 PM CDT (02:56 UTC)
- Expired
- May 24, 2021, 12:00 AM CDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Concerning
- Severe thunderstorm watch 199
All 22 counties
Cheyenne County, KS, Decatur County, KS, Logan County, KS, Rawlins County, KS, Sheridan County, KS, Sherman County, KS, Thomas County, KS, Wallace County, KS, Blaine County, NE, Brown County, NE, Custer County, NE, Dawson County, NE, Dundy County, NE, Frontier County, NE, Hayes County, NE, Hitchcock County, NE, Keya Paha County, NE, Lincoln County, NE, Logan County, NE, Red Willow County, NE, Thomas County, NE, Tripp County, SD
The radar
The North Platte radar (KLNX), 143 km from the middle of the area, began a volume at 02:55 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.
The nearest sounding before it
N. Platte/Lee Bi, NE (KLBF), launched 00:00Z, 2.9 hours before the alert went out and 54 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
- 930 J/kg
- Mixed-layer CIN
- -36 J/kg
- Mixed-layer LCL
- 1216 m above ground
- 0-6 km bulk shear
- 42 kt
- 0-1 km storm-relative helicity
- 161 m²/s²
- 0-3 km storm-relative helicity
- 229 m²/s²
- Significant tornado parameter
- 0.5
- Supercell composite
- 7.0
The text
As transmitted.
127
ACUS11 KWNS 240257
SWOMCD
SPC MCD 240256
SDZ000-NEZ000-KSZ000-COZ000-240500-
Mesoscale Discussion 0719
NWS Storm Prediction Center Norman OK
0956 PM CDT Sun May 23 2021
Areas affected...Central Nebraska...northwest Kansas
Concerning...Severe Thunderstorm Watch 199...
Valid 240256Z - 240500Z
The severe weather threat for Severe Thunderstorm Watch 199
continues.
SUMMARY...Locally strong wind gusts are possible in portions of
central Nebraska. A relatively greater threat for strong/severe wind
gusts will be in northwest Kansas and far southwest Nebraska where
instability remains slightly higher.
DISCUSSION...The line of thunderstorms has weakened in north-central
Nebraska where more limited buoyancy and increasing inhibition
exist. Strong cold-pool driven gusts will remain possible for
perhaps an hour or two more. Farther south into northwest Kansas,
greater instability is evident on objective mesoanalysis. A
relatively greater threat for strong/severe wind gusts will exist
across this region. Given storm mode, marginally severe hail will be
quite isolated if it occurs. The overall trend, though, will be for
storms to continue to decrease in intensity over the next few hours
as inhibition continues to increase to the east.
..Wendt.. 05/24/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...FSD...GID...LBF...UNR...GLD...PUB...
LAT...LON 39920197 41770085 42970043 43420030 43519964 42789941
40529985 39430029 38980073 38520150 38520193 38700225
39920197SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 23, 7:32 PM CDT | Mesoscale Discussion | SPC | Morton | 118 min |
| May 23, 7:53 PM CDT | Mesoscale Discussion | SPC | Cheyenne, Sherman | 67 min |
| May 23, 8:12 PM CDT | Severe Thunderstorm Watch | SPC | Cheyenne, Decatur, Gove, Graham, Greeley, Logan and 7 more | 5 hr |
| May 24, 1:00 PM CDT | Mesoscale Discussion | SPC | Finney, Gove, Grant, Gray, Greeley, Hamilton and 12 more | 2 hr |
| May 24, 1:29 PM CDT | Tornado Watch | SPC | Cheyenne, Decatur, Finney, Gove, Graham, Grant and 18 more | 9 hr |
| May 24, 3:42 PM CDT | Mesoscale Discussion | SPC | Gove, Logan, Rawlins, Sheridan, Thomas | 63 min |
| May 24, 5:37 PM CDT | Mesoscale Discussion | SPC | Decatur, Finney, Gove, Grant, Hamilton, Kearny and 7 more | 113 min |
| May 24, 6:39 PM CDT | Mesoscale Discussion | SPC | Decatur, Norton | 36 min |
| May 23, 8:22 PM CDT | Mesoscale Discussion | SPC | Campbell, Corson, Dewey, Potter, Stanley, Sully and 1 more | 53 min |
Nearby
Mesoscale Discussions in Nebraska, 2021Mesoscale Discussions in Kansas, 2021Mesoscale Discussions in South Dakota, 2021Every mesoscale discussion 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.