Alert archive / Michigan / Mesoscale Discussions in 2012
Mesoscale Discussion 678
The Storm Prediction Center issued this mesoscale discussion at May 3, 2012, 4:33 PM EDT for 21 counties in Michigan. It was in force for 57 min.
The area
The outline as issued.
The facts
- Issued
- May 3, 2012, 4:33 PM EDT (20:33 UTC)
- Expired
- May 3, 2012, 5:30 PM EDT
- In force
- 57 min
- Issued by
- the Storm Prediction Center
All 21 counties
Allegan County, MI, Barry County, MI, Bay County, MI, Calhoun County, MI, Cass County, MI, Clinton County, MI, Eaton County, MI, Genesee County, MI, Gratiot County, MI, Huron County, MI, Ingham County, MI, Ionia County, MI, Kalamazoo County, MI, Kent County, MI, Lapeer County, MI, Livingston County, MI, Saginaw County, MI, Sanilac County, MI, Shiawassee County, MI, Tuscola County, MI, Van Buren County, MI
The radar
The Grand Rapids radar (KGRR), 52 km from the middle of the area, began a volume at 20:33 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
Detroit, MI (KDTX), launched 12:00Z, 8.6 hours before the alert went out and 122 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
- 1476 J/kg
- Mixed-layer CIN
- -58 J/kg
- Mixed-layer LCL
- 948 m above ground
- 0-6 km bulk shear
- 29 kt
- 0-1 km storm-relative helicity
- 212 m²/s²
- 0-3 km storm-relative helicity
- 233 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 3.3
The text
As transmitted, in the capitals the NWS used until 2016.
401 ACUS11 KWNS 032033 SWOMCD SPC MCD 032033 MIZ000-INZ000-032130- MESOSCALE DISCUSSION 0678 NWS STORM PREDICTION CENTER NORMAN OK 0333 PM CDT THU MAY 03 2012 AREAS AFFECTED...CNTRL/SRN LOWER MI CONCERNING...SEVERE THUNDERSTORM WATCH 231... VALID 032033Z - 032130Z THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 231 CONTINUES. SUMMARY...THUNDERSTORMS WILL GRADUALLY SAG INTO NORTHERN PORTIONS OF WW231 OVER THE NEXT FEW HOURS...WHILE NEW DEVELOPMENT IS POSSIBLE ACROSS SW LOWER MI AS WELL. DISCUSSION...STRONG/SEVERE THUNDERSTORMS HAVE EXPANDED ALONG A CORRIDOR FROM CNTRL LAKE HURON...SWWD ACROSS CNTRL LOWER MI INTO SERN WI. THIS ACTIVITY IS GRADUALLY DEVELOPING A COLD POOL WHICH SHOULD ENCOURAGE A SEWD SHIFT TO MORE CONCENTRATED CONVECTION. IN SUPPORT OF THIS IDEA A WELL DEFINED BOW-TYPE STRUCTURE HAS EVOLVED OVER CNTRL LAKE MI AND IS RACING EWD AT 40-45KT. OUTFLOW FROM THIS BAND OF STORMS SHOULD SERVE TO AID ADDITIONAL CONVECTION AS IT APPROACHES MUSKEGON/OTTAWA COUNTIES. IN ADDITION...VIS IMAGERY CLEARLY DEPICTS A LAKE INFLUENCED CONFLUENCE ZONE FROM VAN BUREN COUNTY...NEWD INTO KENT COUNTY. THUNDERSTORMS SHOULD EVOLVE ALONG THIS ZONE OVER THE NEXT FEW HOURS THEN PROGRESS DOWNSTREAM WITH AN ATTENDANT HAIL/WIND THREAT. ..DARROW.. 05/03/2012 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...DTX...IWX...GRR... LAT...LON 42838650 44218251 43058252 41678650 42838650
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 3, 12:51 AM EDT | Mesoscale Discussion | SPC | Manistee, Mason, Oceana | 54 min |
| 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, 6:57 PM EDT | Mesoscale Discussion | SPC | Allegan, Barry, Berrien, Branch, Calhoun, Cass and 28 more | 63 min |
Nearby
Mesoscale 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.