Alert archive / Wisconsin / Mesoscale Discussions in 2012

Mesoscale Discussion 887

May 24, 20125 states

The Storm Prediction Center issued this mesoscale discussion at May 24, 2012, 6:33 AM CDT for 5 states. It was in force for 57 min.

The area

The outline as issued.

The facts

Issued
May 24, 2012, 6:33 AM CDT (11:33 UTC)
Expired
May 24, 2012, 7:30 AM CDT
In force
57 min
Issued by
the Storm Prediction Center
All 67 counties

Allamakee County, IA, Black Hawk County, IA, Bremer County, IA, Buchanan County, IA, Chickasaw County, IA, Clayton County, IA, Delaware County, IA, Dubuque County, IA, Fayette County, IA, Floyd County, IA, Howard County, IA, Linn County, IA, Mitchell County, IA, Winneshiek County, IA, Jo Daviess County, IL, Iron County, MI, Fillmore County, MN, Houston County, MN, Mower County, MN, Olmsted County, MN, Wabasha County, MN, Winona County, MN, Adams County, WI, Brown County, WI, Buffalo County, WI, Chippewa County, WI, Clark County, WI, Columbia County, WI, Crawford County, WI, Dane County, WI, Dunn County, WI, Eau Claire County, WI, Florence County, WI, Forest County, WI, Grant County, WI, Green Lake County, WI, Iowa County, WI, Jackson County, WI, Juneau County, WI, La Crosse County, WI, Lafayette County, WI, Langlade County, WI, Lincoln County, WI, Marathon County, WI, Marinette County, WI, Marquette County, WI, Menominee County, WI, Monroe County, WI, Oconto County, WI, Oneida County, WI, Outagamie County, WI, Pepin County, WI, Portage County, WI, Price County, WI, Richland County, WI, Rusk County, WI, Sauk County, WI, Sawyer County, WI, Shawano County, WI, Taylor County, WI, Trempealeau County, WI, Vernon County, WI, Vilas County, WI, Waupaca County, WI, Waushara County, WI, Winnebago County, WI, Wood County, WI

The radar

The La Crosse radar (KARX), 125 km from the middle of the area, began a volume at 11:34 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 00:00Z, 11.6 hours before the alert went out and 150 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 00:00Z on 2012-05-24Temperature 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 00:00Z on 2012-05-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 127 square meters per square second.1939Sfc1 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
2957 m above ground
0-6 km bulk shear
29 kt
0-1 km storm-relative helicity
127 m²/s²
0-3 km storm-relative helicity
157 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

678 
ACUS11 KWNS 241133
SWOMCD
SPC MCD 241133 
MIZ000-WIZ000-ILZ000-IAZ000-MNZ000-241230-

MESOSCALE DISCUSSION 0887
NWS STORM PREDICTION CENTER NORMAN OK
0633 AM CDT THU MAY 24 2012

AREAS AFFECTED...A LARGE PART OF WI...A SMALL PART OF THE UPPER
PENINSULA OF MI...NERN IA...FAR SERN MN...FAR NWRN IL

CONCERNING...OUTLOOK UPGRADE 

VALID 241133Z - 241230Z

SUMMARY...A CATEGORICAL UPGRADE TO MODERATE RISK WILL OCCUR FOR A
LARGE PART OF WI...A SMALL PART OF THE UPPER PENINSULA OF MI...NERN
IA...FAR SERN MN...AND FAR NWRN IL WITH THE UPCOMING ISSUANCE OF THE
1300 UTC DAY 1 CONVECTIVE OUTLOOK.

DISCUSSION...OBSERVATIONAL TRENDS AND LATEST MODEL GUIDANCE INDICATE
THAT WIDESPREAD SVR WINDS WILL BE POSSIBLE IN ASSOCIATION WITH A
SQUALL LINE THAT IS FORECAST TO CROSS PARTS OF THE UPPER MS VALLEY
THIS AFTERNOON INTO TONIGHT. THIS LINE WILL BE IN ASSOCIATION WITH A
STRONG STORM SYSTEM THAT WILL TRAVERSE THE AREA DURING THE DAY 1
CONVECTIVE PERIOD...AND WILL ALSO FEATURE THE THREAT FOR TORNADOES
AND SVR HAIL. THE ANTICIPATED COVERAGE OF SVR WINDS WILL WARRANT THE
INCLUSION OF A MODERATE RISK IN THE UPCOMING 1300 UTC CONVECTIVE
OUTLOOK...WHICH WILL PROVIDE ADDITIONAL METEOROLOGICAL DETAILS
REGARDING THIS SCENARIO.

..COHEN/CORFIDI.. 05/24/2012

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...MQT...GRB...MKX...DVN...DLH...ARX...MPX...DMX...

LAT...LON   46478868 45648775 44398793 43508876 42249026 42039197
            43259303 45159224 46269057 46478868

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 24, 3:30 PM CDTSevere Thunderstorm WatchSPCJo Daviess, Mercer, Rock Island4 hr
May 23, 8:56 PM CDTMesoscale DiscussionSPCAudubon, Buena Vista, Calhoun, Carroll, Cass, Cherokee and 23 more94 min
May 24, 1:34 PM CDTMesoscale DiscussionSPCAllamakee, Black Hawk, Bremer, Butler, Cerro Gordo, Chickasaw and 10 more116 min
May 24, 3:06 PM CDTMesoscale DiscussionSPCAllamakee, Appanoose, Benton, Black Hawk, Bremer, Buchanan and 38 more114 min
May 24, 5:42 PM CDTMesoscale DiscussionSPCAllamakee, Appanoose, Benton, Black Hawk, Buchanan, Cedar and 24 more2 hr
May 24, 2:22 PM CDTTornado WatchSPCBaraga, Gogebic, Houghton, Iron, Ontonagon5 hr
May 24, 5:41 PM CDTMesoscale DiscussionSPCBaraga, Gogebic, Houghton, Iron2 hr

Nearby

Mesoscale Discussions in Wisconsin, 2012Mesoscale Discussions in Iowa, 2012Mesoscale Discussions in Minnesota, 2012Every mesoscale discussion in 2012

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.