Alert archive / Nebraska / Mesoscale Discussions in 2021
Mesoscale Discussion 2031
The Storm Prediction Center issued this mesoscale discussion at Dec 15, 2021, 4:05 PM CST for 5 counties in Nebraska; Todd County, South Dakota. It was in force for 3 hr.
The area
The outline as issued.
The facts
- Issued
- Dec 15, 2021, 4:05 PM CST (22:05 UTC)
- Expired
- Dec 15, 2021, 7:00 PM CST
- In force
- 3 hr
- Issued by
- the Storm Prediction Center
- Concerning
- Blizzard
Counties Brown County, NE, Cherry County, NE, Hooker County, NE, Keya Paha County, NE, Thomas County, NE, Todd County, SD
The radar
The North Platte radar (KLNX), 53 km from the middle of the area, began a volume at 22:07 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 12:00Z, 10.1 hours before the alert went out and 145 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
- 2654 m above ground
- 0-6 km bulk shear
- 53 kt
- 0-1 km storm-relative helicity
- 127 m²/s²
- 0-3 km storm-relative helicity
- 111 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
202
ACUS11 KWNS 152206
SWOMCD
SPC MCD 152205
NEZ000-SDZ000-160100-
Mesoscale Discussion 2031
NWS Storm Prediction Center Norman OK
0405 PM CST Wed Dec 15 2021
Areas affected...Northern Nebraska
Concerning...Blizzard
Valid 152205Z - 160100Z
SUMMARY...Persistent, strong northwesterly winds behind a cold front
may continue to support areas of blizzard conditions across parts of
northern Nebraska. While snow accumulations may be modest, areas of
reduced visibility down to one-quarter mile is probable.
DISCUSSION...Surface observations from northern NE have shown
periods of heavy snow and reduced visibility down to one-quarter
mile over the past 30-60 minutes. While these conditions have been
somewhat localized, strong frontogenesis is occurring within the
925-700 mb layer along a southeastward-surging cold front that will
continue to support areas of moderate snowfall across the region for
at least the next couple of hours. Additionally, modest instability
over the region (250-500 J/kg MUCAPE per recent mesoanalyses) should
support pockets of heavier snowfall. More importantly, strong
northwesterly winds behind the cold front will persist into the
early evening hours with gusts up to 45-55 mph. Given these
temperature/wind combinations, blowing snow model probabilities
suggests areas of blizzard conditions will continue to be probable -
especially over areas with ongoing snowfall.
..Moore.. 12/15/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...LBF...UNR...
LAT...LON 42260142 42960125 43280065 43349998 42899970 42559973
42110011 41560061 41620103 41920133 42260142SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 15, 12:28 PM CST | Mesoscale Discussion | SPC | Adams, Boone, Burt, Butler, Cass, Cedar and 36 more | 2 hr |
| Dec 15, 1:23 PM CST | Tornado Watch | SPC | Adams, Boone, Burt, Butler, Cass, Cedar and 37 more | 7 hr |
| Dec 15, 2:30 PM CST | Mesoscale Discussion | SPC | Boone, Burt, Butler, Cass, Colfax, Cuming and 28 more | 90 min |
| Dec 15, 3:55 PM CST | Mesoscale Discussion | SPC | Burt, Cass, Cedar, Dakota, Dixon, Douglas and 9 more | 95 min |
Nearby
Mesoscale Discussions in Nebraska, 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.