Alert archive / Wisconsin / Mesoscale Discussions in 2017

Mesoscale Discussion 748

May 17, 2017Allamakee County, Clayton County, Iowa; Houston County, Winona County, Minnesota; 30 counties in Wisconsin

The Storm Prediction Center issued this mesoscale discussion at May 17, 2017, 12:23 PM CDT for Allamakee County, Clayton County, Iowa; Houston County, Winona County, Minnesota; 30 counties in Wisconsin. It was in force for 97 min.

The area

The outline as issued.

The facts

Issued
May 17, 2017, 12:23 PM CDT (17:23 UTC)
Expired
May 17, 2017, 2:00 PM CDT
In force
97 min
Issued by
the Storm Prediction Center
Chance of a watch
60%
All 34 counties

Allamakee County, IA, Clayton County, IA, Houston County, MN, Winona County, MN, Adams County, WI, Clark County, WI, Columbia County, WI, Crawford County, WI, Dane County, WI, Dodge County, WI, Eau Claire County, WI, Fond du Lac County, WI, Grant County, WI, Green County, WI, Green Lake County, WI, Iowa County, WI, Jackson County, WI, Jefferson County, WI, Juneau County, WI, La Crosse County, WI, Lafayette County, WI, Marathon County, WI, Marquette County, WI, Monroe County, WI, Portage County, WI, Richland County, WI, Sauk County, WI, Taylor County, WI, Trempealeau County, WI, Vernon County, WI, Waupaca County, WI, Waushara County, WI, Winnebago County, WI, Wood County, WI

The radar

The La Crosse radar (KARX), 84 km from the middle of the area, began a volume at 17:22 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Green Bay/Straub, WI (KGRB), launched 12:00Z, 5.4 hours before the alert went out and 175 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-pSkew-T log-p diagram, Green Bay/Straub, WI at 12:00Z on 2017-05-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Green Bay/Straub, WI at 12:00Z on 2017-05-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 8 square meters per square second.1939587897Sfc1 km3 km6 km9 kmRMLM
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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1435 m above ground
0-6 km bulk shear
70 kt
0-1 km storm-relative helicity
8 m²/s²
0-3 km storm-relative helicity
81 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 16, 7:31 PM CDTMesoscale DiscussionSPCAdair, Adams, Audubon, Benton, Black Hawk, Boone and 59 more59 min
May 16, 8:46 PM CDTSevere Thunderstorm WatchSPCAllamakee, Black Hawk, Boone, Bremer, Butler, Cerro Gordo and 29 more5 hr
May 16, 9:43 PM CDTMesoscale DiscussionSPCAdair, Adams, Audubon, Calhoun, Carroll, Cass and 16 more62 min
May 16, 11:48 PM CDTMesoscale DiscussionSPCAdair, Allamakee, Black Hawk, Boone, Bremer, Butler and 28 more117 min
May 17, 11:39 AM CDTMesoscale DiscussionSPCAdair, Adams, Appanoose, Audubon, Boone, Carroll and 28 more66 min
May 17, 12:08 PM CDTTornado WatchSPCAdair, Adams, Appanoose, Audubon, Black Hawk, Boone and 64 more7 hr
May 17, 2:25 PM CDTMesoscale DiscussionSPCAdair, Adams, Audubon, Boone, Calhoun, Carroll and 32 more65 min
May 17, 2:38 PM CDTMesoscale DiscussionSPCAllamakee, Benton, Black Hawk, Bremer, Buchanan, Butler and 15 more97 min
May 17, 3:13 PM CDTTornado WatchSPCAllamakee, Chickasaw, Clayton, Fayette, Floyd, Howard and 2 more9 hr
May 17, 3:24 PM CDTMesoscale DiscussionSPCBenton, Buchanan, Cedar, Clinton, Davis, Delaware and 17 more66 min
May 17, 3:44 PM CDTTornado WatchSPCBenton, Buchanan, Cedar, Clinton, Delaware, Des Moines and 15 more9 hr
May 17, 6:05 PM CDTMesoscale DiscussionSPCAllamakee, Benton, Black Hawk, Bremer, Buchanan, Cedar and 18 more55 min
May 16, 9:14 PM CDTMesoscale DiscussionSPCWabasha61 min
May 17, 2:53 PM CDTTornado WatchSPCBlue Earth, Brown, Cottonwood, Dakota, Faribault, Freeborn and 16 more6 hr
May 16, 9:47 PM CDTSevere Thunderstorm WatchSPCAdams, Buffalo, Clark, Jackson, Juneau, La Crosse and 14 more5 hr
May 17, 6:31 PM CDTMesoscale DiscussionSPCAdams, Chippewa, Clark, Columbia, Dodge, Eau Claire and 17 more89 min

Nearby

Mesoscale Discussions in Wisconsin, 2017Mesoscale Discussions in Iowa, 2017Mesoscale Discussions in Minnesota, 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.