Alert archive / Nebraska / Mesoscale Discussions in 2021
Mesoscale Discussion 1067
The Storm Prediction Center issued this mesoscale discussion at Jun 23, 2021, 2:51 PM MDT for 22 counties in Nebraska. It was in force for 114 min.
The area
The outline as issued.
The facts
- Issued
- Jun 23, 2021, 2:51 PM MDT (20:51 UTC)
- Expired
- Jun 23, 2021, 4:45 PM MDT
- In force
- 114 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch possible
- Chance of a watch
- 40%
All 22 counties
Arthur County, NE, Banner County, NE, Blaine County, NE, Box Butte County, NE, Brown County, NE, Cherry County, NE, Cheyenne County, NE, Custer County, NE, Deuel County, NE, Garden County, NE, Grant County, NE, Hooker County, NE, Keith County, NE, Keya Paha County, NE, Lincoln County, NE, Logan County, NE, Loup County, NE, McPherson County, NE, Morrill County, NE, Rock County, NE, Sheridan County, NE, Thomas County, NE
The radar
The North Platte radar (KLNX), 82 km from the middle of the area, began a volume at 20:55 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 watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
N. Platte/Lee Bi, NE (KLBF), launched 12:00Z, 8.9 hours before the alert went out and 109 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
- 211 J/kg
- Mixed-layer CIN
- -469 J/kg
- Mixed-layer LCL
- 2679 m above ground
- 0-6 km bulk shear
- 32 kt
- 0-1 km storm-relative helicity
- 32 m²/s²
- 0-3 km storm-relative helicity
- 100 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.0
The text
As transmitted.
710
ACUS11 KWNS 232051
SWOMCD
SPC MCD 232051
NEZ000-COZ000-232245-
Mesoscale Discussion 1067
NWS Storm Prediction Center Norman OK
0351 PM CDT Wed Jun 23 2021
Areas affected...Portions of the Nebraska Panhandle and
north-central Nebraska.
Concerning...Severe potential...Watch possible
Valid 232051Z - 232245Z
Probability of Watch Issuance...40 percent
SUMMARY...Increasing storm coverage and intensity expected into the
evening.
DISCUSSION...A few towers have started to develop in the well-mixed
air in the Nebraska Panhandle where temperatures are over 100
degrees and inhibition is eroded according to SPC mesoanalysis.
MLCAPE is only around 500 J/kg in this region and thus, storms are
expected to strengthen gradually. However, as this activity moves
eastward and as the upper trough advances east toward the better
instability, storm intensity/coverage is expected to increase. In
addition, shear is relatively weak where early development has
begun, but it is stronger across central and eastern Nebraska. This
should also aid in storm intensity/organization as activity moves
east. Additionally, the low-level jet is expected to strengthen
substantially during the evening hours which should provide
additional forcing for storm development.
At some point during this evening, a severe thunderstorm watch will
likely be needed, especially as storms organize into
supercells/bowing segments. However, the timing of this transition
remains unclear and thus storm trends will be monitored over the
next few hours.
..Bentley/Hart.. 06/23/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...GID...LBF...BOU...CYS...
LAT...LON 42280331 42910169 42949956 42369904 41529924 41060000
41040120 40990238 41050333 41480389 42280331SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 22, 8:51 PM MDT | Mesoscale Discussion | SPC | Butler, Clay, Fillmore, Gage, Hamilton, Jefferson and 6 more | 54 min |
| Jun 23, 3:40 PM MDT | Severe Thunderstorm Watch | SPC | Arthur, Blaine, Boyd, Brown, Cherry, Custer and 16 more | 6 hr |
| Jun 23, 5:13 PM MDT | Mesoscale Discussion | SPC | Antelope, Blaine, Boone, Boyd, Brown, Burt and 25 more | 92 min |
Nearby
Mesoscale Discussions in Nebraska, 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.