Alert archive / Nebraska / Mesoscale Discussions in 2018
Mesoscale Discussion 621
The Storm Prediction Center issued this mesoscale discussion at Jun 1, 2018, 9:32 PM CDT for 38 counties in Nebraska. It was in force for 118 min.
The area
The outline as issued.
The facts
- Issued
- Jun 1, 2018, 9:32 PM CDT (02:32 UTC)
- Expired
- Jun 1, 2018, 11:30 PM CDT
- In force
- 118 min
- Issued by
- the Storm Prediction Center
All 38 counties
Adams County, NE, Antelope County, NE, Boone County, NE, Buffalo County, NE, Butler County, NE, Clay County, NE, Colfax County, NE, Dodge County, NE, Fillmore County, NE, Franklin County, NE, Gage County, NE, Garfield County, NE, Greeley County, NE, Hall County, NE, Hamilton County, NE, Howard County, NE, Jefferson County, NE, Kearney County, NE, Knox County, NE, Lancaster County, NE, Madison County, NE, Merrick County, NE, Nance County, NE, Nuckolls County, NE, Phelps County, NE, Pierce County, NE, Platte County, NE, Polk County, NE, Saline County, NE, Saunders County, NE, Seward County, NE, Sherman County, NE, Stanton County, NE, Thayer County, NE, Valley County, NE, Webster County, NE, Wheeler County, NE, York County, NE
The radar
The Grand Island radar (KUEX), 98 km from the middle of the area, began a volume at 02:32 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
Omaha, NE (KOAX), launched 00:00Z, 2.5 hours before the alert went out and 169 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
- 839 J/kg
- Mixed-layer CIN
- -325 J/kg
- Mixed-layer LCL
- 2411 m above ground
- 0-6 km bulk shear
- 42 kt
- 0-1 km storm-relative helicity
- 62 m²/s²
- 0-3 km storm-relative helicity
- 207 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
229
ACUS11 KWNS 020232
SWOMCD
SPC MCD 020232
NEZ000-SDZ000-020430-
Mesoscale Discussion 0621
NWS Storm Prediction Center Norman OK
0932 PM CDT Fri Jun 01 2018
Areas affected...Eastern and Southern Nebraska
Concerning...Tornado Watch 147...
Valid 020232Z - 020430Z
The severe weather threat for Tornado Watch 147 continues.
SUMMARY...Damaging wind gusts and large hail will be likely with
storms moving across east-central Nebraska late this evening. The
severe threat is expected to continue past the 11 pm CDT expiration.
For this reason, a new weather watch will be needed around 03Z for
parts of the central Plains to replace tornado watch 147.
DISCUSSION...The latest surface analysis shows a cold front in
central Nebraska with a corridor of low-level moisture extending
northward from Kansas into southeast Nebraska. A linear MCS with
severe thunderstorms, is ongoing along the northern edge of the
moist corridor along an enhanced zone of low-level convergence. This
MCS is forecast to move southeastward along a gradient of
instability into southeast Nebraska over the next few hours. MLCAPE
values in the 3000 to 4000 J/kg range along with moderate deep-layer
shear will be favorable to continue a severe threat through late
evening into the overnight period. The more intense parts of the
line could produce wind damage and isolated large hail. Due to the
continued severe threat, a new watch is planned to be issued around
03Z to replace the ongoing tornado watch.
..Broyles/Thompson.. 06/02/2018
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...FSD...OAX...GID...LBF...
LAT...LON 42799794 41869906 41199967 40889981 40449978 40119891
40019771 40209637 41719662 42799794SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 1, 7:08 PM CDT | Mesoscale Discussion | SPC | Adams, Boyd, Buffalo, Clay, Garfield, Greeley and 12 more | 2 hr |
| Jun 1, 10:05 PM CDT | Severe Thunderstorm Watch | SPC | Adams, Boone, Buffalo, Burt, Butler, Cass and 45 more | 5 hr |
| Jun 2, 12:50 AM CDT | Mesoscale Discussion | SPC | Gage, Johnson, Nemaha, Otoe, Pawnee, Richardson | 55 min |
Nearby
Mesoscale Discussions in Nebraska, 2018Every mesoscale discussion in 2018
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.