Alert archive / Wisconsin / Mesoscale Discussions in 2021
Mesoscale Discussion 1445
The Storm Prediction Center issued this mesoscale discussion at Aug 8, 2021, 3:53 PM CDT for 28 counties in Wisconsin. It was in force for 97 min.
The area
The outline as issued.
The facts
- Issued
- Aug 8, 2021, 3:53 PM CDT (20:53 UTC)
- Expired
- Aug 8, 2021, 5:30 PM CDT
- In force
- 97 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe thunderstorm watch 416
All 28 counties
Adams County, WI, Brown County, WI, Calumet County, WI, Clark County, WI, Columbia County, WI, Dodge County, WI, Fond du Lac County, WI, Green Lake County, WI, Juneau County, WI, Kewaunee County, WI, Langlade County, WI, Lincoln County, WI, Manitowoc County, WI, Marathon County, WI, Marquette County, WI, Menominee County, WI, Oconto County, WI, Outagamie County, WI, Ozaukee County, WI, Portage County, WI, Shawano County, WI, Sheboygan County, WI, Taylor County, WI, Washington County, WI, Waupaca County, WI, Waushara County, WI, Winnebago County, WI, Wood County, WI
The radar
The Green Bay radar (KGRB), 91 km from the middle of the area, began a volume at 20:53 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
Green Bay/Straub, WI (KGRB), launched 12:00Z, 8.9 hours before the alert went out and 92 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
- 445 J/kg
- Mixed-layer CIN
- -23 J/kg
- Mixed-layer LCL
- 568 m above ground
- 0-6 km bulk shear
- 18 kt
- 0-1 km storm-relative helicity
- 108 m²/s²
- 0-3 km storm-relative helicity
- 44 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
535
ACUS11 KWNS 082053
SWOMCD
SPC MCD 082053
WIZ000-MIZ000-082230-
Mesoscale Discussion 1445
NWS Storm Prediction Center Norman OK
0353 PM CDT Sun Aug 08 2021
Areas affected...central and eastern Wisconsin
Concerning...Severe Thunderstorm Watch 416...
Valid 082053Z - 082230Z
The severe weather threat for Severe Thunderstorm Watch 416
continues.
SUMMARY...The threat for isolated severe hail, damaging winds, and a
brief tornado continues across watch 416.
DISCUSSION...Temperatures across eastern and central Wisconsin have
warmed into the mid 80s with dewpoints in the low to mid 70s. This
is yielding MLCAPE around 2000 J/kg. Effective shear has weakened
across the area as mid-level winds have weakened to around 30 knots
out of the south on area VWPs. This may be partially responsible for
the seemingly unorganized nature of the convection thus far.
However, some clustering has occurred in Adams and Marquette
counties with occasional weak rotation. Relatively weak winds in the
lowest 2km should limit the tornado threat, but backed surface winds
downstream of this activity could support a brief tornado.
..Bentley/Thompson.. 08/08/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...MQT...GRB...MKX...ARX...
LAT...LON 43148952 43839013 44619081 45099089 45488968 45048721
44708715 43058788 43148952SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 8, 12:57 PM CDT | Mesoscale Discussion | SPC | Adams, Brown, Calumet, Columbia, Crawford, Dodge and 22 more | 93 min |
| Aug 8, 1:59 PM CDT | Severe Thunderstorm Watch | SPC | Adams, Brown, Calumet, Clark, Columbia, Dodge and 20 more | 6 hr |
Nearby
Mesoscale Discussions in Wisconsin, 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.