Alert archive / Wisconsin / Mesoscale Discussions in 2021

Mesoscale Discussion 738

May 25, 2021Gogebic County, Iron County, Ontonagon County, Michigan; Winona County, Minnesota; 20 counties in Wisconsin

The Storm Prediction Center issued this mesoscale discussion at May 25, 2021, 5:17 PM CDT for Gogebic County, Iron County, Ontonagon County, Michigan; Winona County, Minnesota; 20 counties in Wisconsin. It was in force for 118 min.

The area

The outline as issued.

The facts

Issued: May 25, 2021, 5:17 PM CDT (22:17 UTC)
Expired: May 25, 2021, 7:15 PM CDT
In force: 118 min
Issued by: the Storm Prediction Center
Concerning: Severe thunderstorm watch 203

All 24 counties

Gogebic County, MI, Iron County, MI, Ontonagon County, MI, Winona County, MN, Buffalo County, WI, Chippewa County, WI, Clark County, WI, Eau Claire County, WI, Forest County, WI, Iron County, WI, Jackson County, WI, Juneau County, WI, La Crosse County, WI, Langlade County, WI, Lincoln County, WI, Marathon County, WI, Monroe County, WI, Oneida County, WI, Portage County, WI, Price County, WI, Taylor County, WI, Trempealeau County, WI, Vilas County, WI, Wood County, WI

The radar

The La Crosse radar (KARX), 166 km from the middle of the area, began a volume at 22:18 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, 10.3 hours before the alert went out and 197 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.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 96 J/kg
Mixed-layer CIN: -140 J/kg
Mixed-layer LCL: 1118 m above ground
0-6 km bulk shear: 37 kt
0-1 km storm-relative helicity: 125 m²/s²
0-3 km storm-relative helicity: 155 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

Open this sounding in Storm Lab

The text

As transmitted.

177 
ACUS11 KWNS 252217
SWOMCD
SPC MCD 252217 
MIZ000-WIZ000-MNZ000-260015-

Mesoscale Discussion 0738
NWS Storm Prediction Center Norman OK
0517 PM CDT Tue May 25 2021

Areas affected...Portions of central/northern Wisconsin and western
Upper Peninsula of Michigan

Concerning...Severe Thunderstorm Watch 203...

Valid 252217Z - 260015Z

The severe weather threat for Severe Thunderstorm Watch 203
continues.

SUMMARY...A linear segment has developed in west-central Wisconsin.
This activity will pose an increased damaging wind threat as it
moves into central Wisconsin. More isolated, discrete storms in
portions of the Northwoods will have a greater hail threat.

DISCUSSION...Storms have recently begun to cluster in parts of
west-central Wisconsin. Estimated 60 mph wind gusts have been
reported near Arcadia, WI in the last 15-20 minutes. As this
activity moves east into the Central Sands region, temperatures in
the low 80s F and dewpoints in the mid 60s F will support an
increased risk for damaging wind gusts given the linear storm mode.
Farther north, buoyancy is slightly more limited and storm coverage
has been more isolated. However, a more robust storm moving from
Taylor County into Lincoln County has shown a MESH values of 1-1.5
inches. These more discrete storms will pose a greater large hail
risk. Deep-layer shear will continue to support storm organization
as storms move east.

..Wendt.. 05/25/2021

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...MQT...GRB...DLH...ARX...MPX...

LAT...LON   44269193 44949154 45629100 46719042 46988954 47038894
            46498842 45388869 44348928 43879016 43779116 43989189
            44269193

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 25, 2:15 PM CDT	Mesoscale Discussion	SPC	Gogebic	2 hr
May 25, 2:53 PM CDT	Severe Thunderstorm Watch	SPC	Baraga, Delta, Dickinson, Gogebic, Houghton, Iron and 2 more	8 hr

Nearby

Mesoscale Discussions in Wisconsin, 2021 Mesoscale Discussions in Michigan, 2021 Mesoscale Discussions in Minnesota, 2021 Every 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.