Alert archive / Nebraska / Mesoscale Discussions in 2021
Mesoscale Discussion 1018
The Storm Prediction Center issued this mesoscale discussion at Jun 19, 2021, 4:00 PM MDT for 6 counties in Colorado; 12 counties in Kansas; 16 counties in Nebraska. It was in force for 90 min.
The area
The outline as issued.
The facts
- Issued
- Jun 19, 2021, 4:00 PM MDT (22:00 UTC)
- Expired
- Jun 19, 2021, 5:30 PM MDT
- In force
- 90 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe thunderstorm watch 286
All 34 counties
Kit Carson County, CO, Logan County, CO, Phillips County, CO, Sedgwick County, CO, Washington County, CO, Yuma County, CO, Cheyenne County, KS, Decatur County, KS, Graham County, KS, Logan County, KS, Norton County, KS, Phillips County, KS, Rawlins County, KS, Rooks County, KS, Sheridan County, KS, Sherman County, KS, Thomas County, KS, Wallace County, KS, Chase County, NE, Cheyenne County, NE, Dawson County, NE, Deuel County, NE, Dundy County, NE, Frontier County, NE, Furnas County, NE, Gosper County, NE, Harlan County, NE, Hayes County, NE, Hitchcock County, NE, Keith County, NE, Lincoln County, NE, Perkins County, NE, Phelps County, NE, Red Willow County, NE
The radar
The Goodland radar (KGLD), 92 km from the middle of the area, began a volume at 22:00 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.
The watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Denver, CO (KDNR), launched 12:00Z, 10.0 hours before the alert went out and 134 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 2627 m above ground
- 0-6 km bulk shear
- 16 kt
- 0-1 km storm-relative helicity
- -23 m²/s²
- 0-3 km storm-relative helicity
- 44 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
929
ACUS11 KWNS 192200
SWOMCD
SPC MCD 192200
KSZ000-NEZ000-COZ000-192330-
Mesoscale Discussion 1018
NWS Storm Prediction Center Norman OK
0500 PM CDT Sat Jun 19 2021
Areas affected...Northeastern Colorado...Southwestern Nebraska...and
Northwestern Kansas
Concerning...Severe Thunderstorm Watch 286...
Valid 192200Z - 192330Z
The severe weather threat for Severe Thunderstorm Watch 286
continues.
SUMMARY...An organized wind threat is developing this
afternoon/evening across northeastern Colorado, southwestern
Nebraska, and northwestern Kansas. A Severe Thunderstorm Watch will
be needed downstream of WW286.
DISCUSSION...Thunderstorms across the eastern Nebraska Panhandle and
northeastern Colorado are rapidly growing upscale and surging
east-southeastward/eastward. Given the favorable environment
downstream, characterized by steep lapse rates, over 2000 J/kg of
MUCAPE, and 30-40 knots of effective bulk shear, continued upscale
growth and organization is expected. In addition, the southerly
low-level jet is expected to increase this evening across central
Kansas, providing additional support for convective maintenance and
organization. All factors are supportive of the development of a
severe-wind-producing MCS, including potential for significant
severe winds, over the next several hours.
..Jirak/Guyer.. 06/19/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...GID...LBF...DDC...GLD...BOU...CYS...
LAT...LON 39910363 40420368 40820348 41340294 41680270 41440154
41100057 40969964 40529908 39839885 39389923 38999999
38850164 38900310 39120374 39910363SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 19, 12:46 PM MDT | Mesoscale Discussion | SPC | Adams, Arapahoe, Cheyenne, Elbert, Kiowa, Kit Carson and 8 more | 89 min |
| Jun 19, 1:44 PM MDT | Severe Thunderstorm Watch | SPC | Adams, Arapahoe, Baca, Bent, Cheyenne, Crowley and 17 more | 7 hr |
| Jun 19, 3:24 PM MDT | Mesoscale Discussion | SPC | Logan, Morgan, Phillips, Sedgwick, Washington, Yuma | 2 hr |
| Jun 19, 4:48 PM MDT | Severe Thunderstorm Watch | SPC | Cheyenne, Decatur, Ellis, Gove, Graham, Greeley and 15 more | 6 hr |
| Jun 18, 8:27 PM MDT | Mesoscale Discussion | SPC | Cass, Gage, Johnson, Lancaster, Nemaha, Otoe and 2 more | 2 hr |
| Jun 18, 9:08 PM MDT | Severe Thunderstorm Watch | SPC | Johnson, Nemaha, Pawnee, Richardson | 8 hr |
| Jun 19, 3:58 PM MDT | Mesoscale Discussion | SPC | Dawes | 92 min |
Nearby
Mesoscale Discussions in Nebraska, 2021Mesoscale Discussions in Kansas, 2021Mesoscale Discussions in Colorado, 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.