Alert archive / Wisconsin / Mesoscale Discussions in 2021
Mesoscale Discussion 992
The Storm Prediction Center issued this mesoscale discussion at Jun 17, 2021, 10:52 PM CDT for Allamakee County, Howard County, Winneshiek County, Iowa; 6 counties in Minnesota; 19 counties in Wisconsin. It was in force for 83 min.
The area
The outline as issued.
The facts
- Issued
- Jun 17, 2021, 10:52 PM CDT (03:52 UTC)
- Expired
- Jun 18, 2021, 12:15 AM CDT
- In force
- 83 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe thunderstorm watch 278
All 28 counties
Allamakee County, IA, Howard County, IA, Winneshiek County, IA, Fillmore County, MN, Houston County, MN, Mower County, MN, Olmsted County, MN, Wabasha County, MN, Winona County, MN, Adams County, WI, Buffalo County, WI, Columbia County, WI, Crawford County, WI, Dodge County, WI, Fond du Lac County, WI, Green Lake County, WI, Jackson County, WI, Juneau County, WI, La Crosse County, WI, Marquette County, WI, Monroe County, WI, Richland County, WI, Sauk County, WI, Trempealeau County, WI, Vernon County, WI, Waushara County, WI, Winnebago County, WI, Wood County, WI
The radar
The La Crosse radar (KARX), 7 km from the middle of the area, began a volume at 03:56 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
Minneapolis, MN (KMPX), launched 00:00Z, 3.9 hours before the alert went out and 229 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
- 61 J/kg
- Mixed-layer CIN
- -387 J/kg
- Mixed-layer LCL
- 1555 m above ground
- 0-6 km bulk shear
- 55 kt
- 0-1 km storm-relative helicity
- -13 m²/s²
- 0-3 km storm-relative helicity
- 56 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.1
The text
As transmitted.
509
ACUS11 KWNS 180352
SWOMCD
SPC MCD 180352
WIZ000-IAZ000-MNZ000-180515-
Mesoscale Discussion 0992
NWS Storm Prediction Center Norman OK
1052 PM CDT Thu Jun 17 2021
Areas affected...Far Southeast MN...Southern WI...Far Northeast IA
Concerning...Severe Thunderstorm Watch 278...
Valid 180352Z - 180515Z
The severe weather threat for Severe Thunderstorm Watch 278
continues.
SUMMARY...The threat for large to very large hail and damaging wind
gusts continues.
DISCUSSION...Cluster of supercells in far southeast MN has continued
to produce large to very large (i.e. greater than 2" diameter) as it
moves southeastward along the the MN/WI border. Recent MESH is
estimating 3 to 3.5"in the storm moving across southwest Winona
County, which is currently the westernmost cell in the cluster.
Given its location, ample moist low-level inflow will be available
to this storm and it will likely maintain a very strong updraft as
it moves into LSE. Additionally, recent radar trends have begun to
indicate a more southeastward motion of the entire cluster,
suggesting the upscale growth/linear transition is likely underway.
..Mosier.. 06/18/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...GRB...MKX...ARX...MPX...
LAT...LON 43839316 44439224 44579023 44298850 43418846 42959061
43299248 43839316SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 17, 7:02 PM CDT | Mesoscale Discussion | SPC | Allamakee, Howard, Mitchell, Winnebago, Winneshiek, Worth | 88 min |
| Jun 17, 9:01 PM CDT | Mesoscale Discussion | SPC | Allamakee, Howard, Mitchell, Winneshiek | 89 min |
| Jun 17, 10:01 PM CDT | Severe Thunderstorm Watch | SPC | Allamakee, Bremer, Butler, Cerro Gordo, Chickasaw, Clayton and 10 more | 6 hr |
| Jun 18, 1:34 AM CDT | Mesoscale Discussion | SPC | Allamakee | 116 min |
| Jun 17, 7:22 PM CDT | Severe Thunderstorm Watch | SPC | Blue Earth, Brown, Dakota, Faribault, Freeborn, Goodhue and 9 more | 4 hr |
| Jun 18, 5:03 PM CDT | Mesoscale Discussion | SPC | Becker, Beltrami, Cass, Clay, Clearwater, Crow Wing and 9 more | 87 min |
Nearby
Mesoscale Discussions in Wisconsin, 2021Mesoscale Discussions in Minnesota, 2021Mesoscale Discussions in Iowa, 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.