Alert archive / Wisconsin / Mesoscale Discussions in 2012

Mesoscale Discussion 1398

July 4, 201217 counties in Michigan; 19 counties in Wisconsin

The Storm Prediction Center issued this mesoscale discussion at Jul 4, 2012, 11:54 PM EDT for 17 counties in Michigan; 19 counties in Wisconsin. It was in force for 96 min.

The area

The outline as issued.

The facts

Issued
Jul 4, 2012, 11:54 PM EDT (03:54 UTC)
Expired
Jul 5, 2012, 1:30 AM EDT
In force
96 min
Issued by
the Storm Prediction Center
Chance of a watch
20%
All 36 counties

Clare County, MI, Gratiot County, MI, Ionia County, MI, Isabella County, MI, Kent County, MI, Lake County, MI, Manistee County, MI, Mason County, MI, Mecosta County, MI, Missaukee County, MI, Montcalm County, MI, Muskegon County, MI, Newaygo County, MI, Oceana County, MI, Osceola County, MI, Ottawa County, MI, Wexford County, MI, Adams County, WI, Calumet County, WI, Columbia County, WI, Dodge County, WI, Fond du Lac County, WI, Green Lake County, WI, Jefferson County, WI, Manitowoc County, WI, Marquette County, WI, Milwaukee County, WI, Ozaukee County, WI, Portage County, WI, Racine County, WI, Sheboygan County, WI, Washington County, WI, Waukesha County, WI, Waupaca County, WI, Waushara County, WI, Winnebago County, WI

The radar

The Green Bay radar (KGRB), 102 km from the middle of the area, began a volume at 03:54 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, 3.9 hours before the alert went out and 100 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 2012-07-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 5454 joules per kilogram.LCLLFCEL10008507005003002001001 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 2012-07-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 78 square meters per square second.193958Sfc1 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
5454 J/kg
Mixed-layer CIN
-37 J/kg
Mixed-layer LCL
1029 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
78 m²/s²
0-3 km storm-relative helicity
112 m²/s²
Significant tornado parameter
2.5
Supercell composite
13.0

Open this sounding in Storm Lab

The text

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

311 
ACUS11 KWNS 050355
SWOMCD
SPC MCD 050354
MIZ000-WIZ000-050530-

MESOSCALE DISCUSSION 1398
NWS STORM PREDICTION CENTER NORMAN OK
1054 PM CDT WED JUL 04 2012

AREAS AFFECTED...CNTRL WI INTO CNTRL LOWER MI

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY

VALID 050354Z - 050530Z

PROBABILITY OF WATCH ISSUANCE...20 PERCENT

SUMMARY...STORMS WILL MOVE SWD ACROSS THE AREA WITH GUSTY WINDS AND
MARGINAL HAIL POSSIBLE.

DISCUSSION...AN OUTFLOW BOUNDARY CONTINUES TO PUSH SWD ACROSS ERN WI
EWD ACROSS LAKE MICHIGAN...WITH CELLS FORMING ALONG AND BEHIND.
ALTHOUGH STRONG INSTABILITY EXISTS AS SEEN ON 00Z GRB
SOUNDING...CONTINUED COOLING IN THE BOUNDARY LAYER AND LIKELY
SHALLOW CONVERGENCE HAS STYMIED GROWTH POTENTIAL OF THESE STORMS.
NONETHELESS...GUSTY WINDS OF 30-40 KT APPEAR LIKELY WITH THE PASSAGE
OF THESE STORMS AND OUTFLOW. A FEW CORES MAY BRIEFLY YIELD
MARGINALLY SEVERE HAIL...BUT WITH WEAK SHEAR PROFILES...THEY ARE NOT
EXPECTED TO BE LONG LIVED.

..JEWELL/CORFIDI.. 07/05/2012

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

ATTN...WFO...DTX...APX...GRR...GRB...MKX...ARX...

LAT...LON   44668948 44338843 44208737 44298644 44628554 43878431
            43258452 42868498 42778547 42638603 42618673 42808794
            43078902 43388954 43738992 44119013 44498991 44668948

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 5, 2:57 AM EDTMesoscale DiscussionSPCBarry, Branch, Calhoun, Clinton, Eaton, Genesee and 19 more63 min
Jul 5, 3:04 AM EDTSevere Thunderstorm WatchSPCBarry, Calhoun, Eaton, Genesee, Ingham, Ionia and 11 more3 hr
Jul 5, 4:12 AM EDTMesoscale DiscussionSPCGenesee, Ingham, Jackson, Lenawee, Livingston, Macomb and 4 more93 min
Jul 5, 3:27 PM EDTMesoscale DiscussionSPCBranch, Hillsdale, Jackson, Lenawee, Monroe, Washtenaw and 1 more93 min
Jul 5, 5:58 PM EDTMesoscale DiscussionSPCBerrien, Branch, Cass, Saint Joseph92 min
Jul 4, 8:31 PM EDTSevere Thunderstorm WatchSPCAshland, Bayfield, Burnett, Douglas, Iron, Price and 2 more5 hr
Jul 4, 9:59 PM EDTTornado WatchSPCBarron, Burnett, Polk, Rusk, Sawyer, Washburn5 hr

Nearby

Mesoscale Discussions in Wisconsin, 2012Mesoscale Discussions in Michigan, 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.