Alert archive / Wisconsin / Mesoscale Discussions in 2012
Mesoscale Discussion 671
The Storm Prediction Center issued this mesoscale discussion at May 3, 2012, 12:51 AM EDT for Manistee County, Mason County, Oceana County, Michigan; 26 counties in Wisconsin. It was in force for 54 min.
The area
The outline as issued.
The facts
- Issued
- May 3, 2012, 12:51 AM EDT (04:51 UTC)
- Expired
- May 3, 2012, 1:45 AM EDT
- In force
- 54 min
- Issued by
- the Storm Prediction Center
All 29 counties
Manistee County, MI, Mason County, MI, Oceana County, MI, Adams County, WI, Brown County, WI, Calumet County, WI, Clark County, WI, Columbia County, WI, Dodge County, WI, Fond du Lac County, WI, Green Lake County, WI, Jackson County, WI, Juneau County, WI, Kewaunee County, WI, Manitowoc County, WI, Marathon County, WI, Marquette County, WI, Monroe County, WI, Outagamie County, WI, Ozaukee County, WI, Portage County, WI, Sauk County, WI, Shawano County, WI, Sheboygan County, WI, Washington County, WI, Waupaca County, WI, Waushara County, WI, Winnebago County, WI, Wood County, WI
The radar
The Green Bay radar (KGRB), 70 km from the middle of the area, began a volume at 04:52 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, 4.9 hours before the alert went out and 69 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
- 86 J/kg
- Mixed-layer CIN
- -138 J/kg
- Mixed-layer LCL
- 1790 m above ground
- 0-6 km bulk shear
- 47 kt
- 0-1 km storm-relative helicity
- 30 m²/s²
- 0-3 km storm-relative helicity
- 95 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.1
The text
As transmitted, in the capitals the NWS used until 2016.
384
ACUS11 KWNS 030451
SWOMCD
SPC MCD 030451
MIZ000-WIZ000-030545-
MESOSCALE DISCUSSION 0671
NWS STORM PREDICTION CENTER NORMAN OK
1151 PM CDT WED MAY 02 2012
AREAS AFFECTED...CENTRAL AND EAST CENTRAL WI
CONCERNING...SEVERE THUNDERSTORM WATCH 227...
VALID 030451Z - 030545Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 227
CONTINUES.
SUMMARY...TSTMS LOCATED OVER CENTRAL INTO EAST CENTRAL WI WILL
PERSIST THROUGH THE OVERNIGHT PERIOD...EVENTUALLY AFFECTING MORE OF
CENTRAL AND NRN LAKE MICHIGAN AND PARTS OF NRN LOWER MI. OVERALL
SEVERE WEATHER THREAT SHOULD CONTINUE TO WANE...WITH THE POTENTIAL
FOR A NEW WW TO THE E OF 227 LOW AT THIS TIME.
DISCUSSION...AT 0430Z...REGIONAL RADAR IMAGERY SHOWED THE STRONGEST
STORMS WERE LOCATED OVER ERN JACKSON/SERN CLARK COUNTIES WI...WITH
ADDITIONAL ACTIVITY EXTENDING FROM SAUK COUNTY WI TO THE NW OF
MKE...WHILE STORMS ALSO EXTENDED EWD FROM THE ERN EXTENT OF WW 227
TO MTW AND ACROSS CENTRAL LAKE MICHIGAN TO WEST CENTRAL LOWER MI.
TRENDS WITH THE STRONGER STORMS IN JACKSON/CLARK COUNTIES INDICATED
A TURN TO THE NE FROM THE PREVIOUS E/SEWD MOVEMENT WHICH IS
SUGGESTIVE OF THE STORM BECOMING MORE REMOVED FROM THE INFLUENCE OF
SURFACE BASED PARCELS. MEANWHILE...THE MORE WIDESPREAD ACTIVITY
THAT DEVELOPED DOWNSTREAM TO THE E OF WW 227 APPEARS TO BE ELEVATED
AND LIKELY ROOTED IN THE 850-700 MB LAYER PER THE CAP EVIDENT ON THE
00Z DVN SOUNDING AND MODIFIED 00Z GRB SOUNDING DUE TO NIGHTTIME
SURFACE COOLING.
LOW LEVEL WAA REGIME EXTENDING FROM CENTRAL INTO ERN WI ALONG THE
NOSE OF A 40-45 KT SSWLY LLJ INTO THE SRN HALF OF WI WILL LIKELY
MAINTAIN THE STORM DEVELOPMENT OVERNIGHT. A LOW SEVERE WEATHER
THREAT IS EXPECTED AS ACTIVITY CONTINUES TO MOVE AWAY FROM STRONGER
INSTABILITY. THE GREATEST POTENTIAL FOR AN ISOLATED SEVERE WEATHER
THREAT SHOULD...HOWEVER...BE CONFINED TO THE SWRN-SRN EXTENT OF THIS
TSTM ACTIVITY WHERE THE INFLOW OF HIGHER THETAE AIR MASS/INSTABILITY
WILL BE CLOSER TO THE LLJ. EFFECTIVE BULK SHEAR OF 40-50 KT WOULD
SUPPORT ORGANIZED STORMS WITH THE STRONGER ACTIVITY.
..PETERS.. 05/03/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...APX...GRR...GRB...MKX...ARX...MPX...
LAT...LON 43459062 44569119 44999029 44858835 44638757 44568598
43898595 43318675 43198831 43318983 43459062SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 3, 11:34 AM EDT | Mesoscale Discussion | SPC | Arenac, Bay, Clare, Clinton, Genesee, Gladwin and 28 more | 86 min |
| May 3, 12:41 PM EDT | Severe Thunderstorm Watch | SPC | Alcona, Alpena, Antrim, Arenac, Bay, Benzie and 23 more | 5 hr |
| May 3, 2:35 PM EDT | Severe Thunderstorm Watch | SPC | Allegan, Barry, Berrien, Branch, Calhoun, Cass and 27 more | 8 hr |
| May 3, 2:39 PM EDT | Mesoscale Discussion | SPC | Antrim, Arenac, Bay, Benzie, Clare, Crawford and 18 more | 66 min |
| May 3, 3:53 PM EDT | Mesoscale Discussion | SPC | Berrien | 67 min |
| May 3, 4:33 PM EDT | Mesoscale Discussion | SPC | Allegan, Barry, Bay, Calhoun, Cass, Clinton and 15 more | 57 min |
| May 3, 6:57 PM EDT | Mesoscale Discussion | SPC | Allegan, Barry, Berrien, Branch, Calhoun, Cass and 28 more | 63 min |
| May 2, 8:38 PM EDT | Mesoscale Discussion | SPC | Adams, Buffalo, Jackson, Juneau, La Crosse, Monroe and 4 more | 37 min |
| May 2, 8:47 PM EDT | Severe Thunderstorm Watch | SPC | Adams, Buffalo, Clark, Jackson, Juneau, La Crosse and 3 more | 5 hr |
| May 3, 9:43 AM EDT | Mesoscale Discussion | SPC | Adams, Brown, Buffalo, Calumet, Clark, Columbia and 26 more | 92 min |
| May 3, 2:07 PM EDT | Severe Thunderstorm Watch | SPC | Columbia, Dane, Dodge, Green, Jefferson, Kenosha and 7 more | 6 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.