Alert archive / Wisconsin / Mesoscale Discussions in 2017
Mesoscale Discussion 1002
The Storm Prediction Center issued this mesoscale discussion at Jun 12, 2017, 6:38 PM CDT for 30 counties in Wisconsin. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Jun 12, 2017, 6:38 PM CDT (23:38 UTC)
- Expired
- Jun 12, 2017, 8:45 PM CDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
All 30 counties
Brown County, WI, Calumet County, WI, Columbia County, WI, Dane County, WI, Dodge County, WI, Fond du Lac County, WI, Green County, WI, Green Lake County, WI, Iowa County, WI, Jefferson County, WI, Kenosha County, WI, Kewaunee County, WI, Lafayette County, WI, Manitowoc County, WI, Menominee County, WI, Milwaukee County, WI, Oconto County, WI, Outagamie County, WI, Ozaukee County, WI, Portage County, WI, Racine County, WI, Rock County, WI, Shawano County, WI, Sheboygan County, WI, Walworth County, WI, Washington County, WI, Waukesha County, WI, Waupaca County, WI, Waushara County, WI, Winnebago County, WI
The radar
The Milwaukee radar (KMKX), 100 km from the middle of the area, began a volume at 23:41 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, 11.6 hours before the alert went out and 99 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
- 851 J/kg
- Mixed-layer CIN
- -179 J/kg
- Mixed-layer LCL
- 1158 m above ground
- 0-6 km bulk shear
- 26 kt
- 0-1 km storm-relative helicity
- 166 m²/s²
- 0-3 km storm-relative helicity
- 137 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.5
The text
As transmitted.
436
ACUS11 KWNS 122339
SWOMCD
SPC MCD 122338
WIZ000-ILZ000-130145-
Mesoscale Discussion 1002
NWS Storm Prediction Center Norman OK
0638 PM CDT Mon Jun 12 2017
Areas affected...Portions of central...southern and eastern WI
Concerning...Severe Thunderstorm Watch 316...319...
Valid 122338Z - 130145Z
The severe weather threat for Severe Thunderstorm Watch 316, 319
continues.
SUMMARY...Severe threat for damaging winds and hail persists across
WW 319 this evening, while these threats have moved east of WW 316
(allowing this latter watch to be canceled early).
DISCUSSION...Mosaic radar imagery showed an ongoing bow advancing to
the east at 35-40 kt across south-central toward eastern WI, with
the bow currently extending from western Waupaca County to Waushara
and Green Lake Counties at the bow apex to Sauk County. From the
apex of the bow, a surface boundary extended eastward to Sheboygan
County and across the middle portion of Lake Michigan. The
environment downstream from the bow remains moderately unstable with
effective bulk shear of 40-50 kt oriented parallel to the surface
boundary. These factors suggest a continued forward propagation of
the bow with damaging winds being the primary threat along the bow
path. Meanwhile, additional strong to severe storm development
remains possible with northward extent (across the WI counties of
Marathon to Oconto) where sufficient instability and strong bulk
shear favor storm organization with a hail and damaging wind threat.
..Peters.. 06/12/2017
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...GRB...LOT...MKX...DVN...ARX...
LAT...LON 42729057 43139011 43908925 44958975 45078953 45308845
44998777 44688680 43418724 42478698 42489023 42729057SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 11, 8:01 PM CDT | Severe Thunderstorm Watch | SPC | Clark, Door, Florence, Forest, Langlade, Lincoln and 7 more | 6 hr |
| Jun 11, 9:39 PM CDT | Mesoscale Discussion | SPC | Chippewa, Clark, Door, Eau Claire, Florence, Forest and 11 more | 2 hr |
| Jun 11, 11:59 PM CDT | Mesoscale Discussion | SPC | Door, Florence, Forest, Langlade, Marathon, Marinette and 3 more | 91 min |
| Jun 12, 11:28 AM CDT | Mesoscale Discussion | SPC | Crawford, La Crosse, Vernon | 92 min |
| Jun 12, 11:47 AM CDT | Severe Thunderstorm Watch | SPC | Adams, Buffalo, Crawford, Grant, Jackson, Juneau and 5 more | 7 hr |
| Jun 12, 2:22 PM CDT | Mesoscale Discussion | SPC | Buffalo, Crawford, Jackson, La Crosse, Monroe, Trempealeau and 1 more | 113 min |
| Jun 12, 4:37 PM CDT | Severe Thunderstorm Watch | SPC | Brown, Calumet, Columbia, Dane, Dodge, Door and 29 more | 5 hr |
Nearby
Mesoscale Discussions in Wisconsin, 2017Every mesoscale discussion in 2017
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.