Alert archive / Wisconsin / Mesoscale Discussions in 2021
Mesoscale Discussion 923
The Storm Prediction Center issued this mesoscale discussion at Jun 11, 2021, 11:34 AM CDT for 9 counties in Minnesota; 34 counties in Wisconsin. It was in force for 116 min.
The area
The outline as issued.
The facts
- Issued
- Jun 11, 2021, 11:34 AM CDT (16:34 UTC)
- Expired
- Jun 11, 2021, 1:30 PM CDT
- In force
- 116 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch unlikely
- Chance of a watch
- 20%
All 43 counties
Dakota County, MN, Dodge County, MN, Fillmore County, MN, Goodhue County, MN, Houston County, MN, Olmsted County, MN, Wabasha County, MN, Washington County, MN, Winona County, MN, Adams County, WI, Barron County, WI, Buffalo County, WI, Burnett County, WI, Chippewa County, WI, Clark County, WI, Dunn County, WI, Eau Claire County, WI, Jackson County, WI, Juneau County, WI, La Crosse County, WI, Langlade County, WI, Lincoln County, WI, Marathon County, WI, Marquette County, WI, Monroe County, WI, Oneida County, WI, Pepin County, WI, Pierce County, WI, Polk County, WI, Portage County, WI, Price County, WI, Richland County, WI, Rusk County, WI, Saint Croix County, WI, Sauk County, WI, Sawyer County, WI, Taylor County, WI, Trempealeau County, WI, Vernon County, WI, Washburn County, WI, Waupaca County, WI, Waushara County, WI, Wood County, WI
The radar
The La Crosse radar (KARX), 90 km from the middle of the area, began a volume at 16:37 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 12:00Z, 4.6 hours before the alert went out and 187 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
- 752 J/kg
- Mixed-layer CIN
- -207 J/kg
- Mixed-layer LCL
- 1602 m above ground
- 0-6 km bulk shear
- 19 kt
- 0-1 km storm-relative helicity
- -28 m²/s²
- 0-3 km storm-relative helicity
- -40 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
264
ACUS11 KWNS 111634
SWOMCD
SPC MCD 111634
WIZ000-IAZ000-MNZ000-111830-
Mesoscale Discussion 0923
NWS Storm Prediction Center Norman OK
1134 AM CDT Fri Jun 11 2021
Areas affected...parts of far southeast Minnesota into central
Wisconsin
Concerning...Severe potential...Watch unlikely
Valid 111634Z - 111830Z
Probability of Watch Issuance...20 percent
SUMMARY...A couple damaging gusts or severe hailstones are possible
with the stronger storms through the afternoon hours. The severe
threat is expected to be too isolated to warrant a WW issuance.
DISCUSSION...Isolated to widely scattered thunderstorm development
has been underway over the past hour or so as diurnal heating has
fostered enough localized lift along multiple diffuse baroclinic
zones. Continued surface heating may promote up to 2000 J/kg MLCAPE
given the presence of upper 60s to near 70F dewpoints, overspread by
6-6.5 C/km mid-level lapse rates. Nonetheless, deep-layer shear is
expected to remain weak given weak upper flow due to the presence of
mid-level ridging. As such, most of the storms are expected to be
relatively short-lived. Any damaging gust/large hail threat that
manifests would be associated with the more isolated, intense
downbursts. Given the isolated, brief nature of the severe threat, a
WW issuance is not expected.
..Squitieri/Grams.. 06/11/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...GRB...MKX...DLH...ARX...MPX...
LAT...LON 44209309 44539314 44769306 45379287 45879256 46189154
46199064 45938914 45338882 44658876 44018893 43518937
43279019 43279113 43529218 43879290 44209309SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 11, 1:58 AM CDT | Severe Thunderstorm Watch | SPC | Clay, Norman, Polk, Wilkin | 5 hr |
| Jun 11, 2:15 AM CDT | Severe Thunderstorm Watch | SPC | Big Stone, Traverse | 5 hr |
| Jun 11, 4:37 AM CDT | Mesoscale Discussion | SPC | Big Stone, Clay, Grant, Kittson, Lac qui Parle, Marshall and 6 more | 83 min |
| Jun 11, 9:35 AM CDT | Mesoscale Discussion | SPC | Blue Earth, Dodge, Faribault, Fillmore, Freeborn, Le Sueur and 8 more | 115 min |
Nearby
Mesoscale Discussions in Wisconsin, 2021Mesoscale Discussions in Minnesota, 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.