Alert archive / Michigan / Mesoscale Discussions in 2012
Mesoscale Discussion 686
The Storm Prediction Center issued this mesoscale discussion at May 3, 2012, 8:36 PM EDT for 24 counties in Michigan. It was in force for 24 min.
The area
The outline as issued.
The facts
- Issued
- May 3, 2012, 8:36 PM EDT (00:36 UTC)
- Expired
- May 3, 2012, 9:00 PM EDT
- In force
- 24 min
- Issued by
- the Storm Prediction Center
All 24 counties
Allegan County, MI, Berrien County, MI, Branch County, MI, Calhoun County, MI, Cass County, MI, Eaton County, MI, Genesee County, MI, Hillsdale County, MI, Ingham County, MI, Jackson County, MI, Kalamazoo County, MI, Lapeer County, MI, Lenawee County, MI, Livingston County, MI, Macomb County, MI, Monroe County, MI, Oakland County, MI, Saint Clair County, MI, Saint Joseph County, MI, Sanilac County, MI, Shiawassee County, MI, Van Buren County, MI, Washtenaw County, MI, Wayne County, MI
The radar
The Detroit radar (KDTX), 48 km from the middle of the area, began a volume at 00:36 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 00:00Z, 0.6 hours before the alert went out and 52 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
- 682 J/kg
- Mixed-layer CIN
- -14 J/kg
- Mixed-layer LCL
- 1887 m above ground
- 0-6 km bulk shear
- 32 kt
- 0-1 km storm-relative helicity
- 113 m²/s²
- 0-3 km storm-relative helicity
- 151 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 3.5
The text
As transmitted, in the capitals the NWS used until 2016.
811
ACUS11 KWNS 040036
SWOMCD
SPC MCD 040036
MIZ000-INZ000-040100-
MESOSCALE DISCUSSION 0686
NWS STORM PREDICTION CENTER NORMAN OK
0736 PM CDT THU MAY 03 2012
AREAS AFFECTED...SRN LOWER MI
CONCERNING...SEVERE THUNDERSTORM WATCH 231...
VALID 040036Z - 040100Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 231
CONTINUES.
SUMMARY...LOCAL TEMPORAL EXTENSION IS BEING CONSIDERED FOR PART OF
SWRN THROUGH SERN LOWER MI WITH AN AREAL EXTENSION FOR THE REST OF
SERN LOWER MI...AS STRONG TO SEVERE STORMS ARE EXPECTED TO PERSIST
THROUGH AT LEAST 03Z.
DISCUSSION...AT 0020Z...REGIONAL RADAR IMAGERY SHOWED THE STRONGEST
STORMS WITHIN WW 231 WERE LOCATED OVER SOUTH CENTRAL AND SWRN LOWER
MI...WHILE AN OUTFLOW BOUNDARY HAD MOVED WELL SOUTH OF THE ACTIVITY
EXTENDING FROM LIVINGSTON TO ST. CLAIR COUNTIES. STRONG STORMS ARE
ALSO MOVING EWD ACROSS THE FAR SRN EXTENT OF LAKE MICHIGAN AND WILL
CONTINUE TO AFFECT SWRN LOWER MI FOR THE NEXT FEW HOURS.
ALTHOUGH THE AIR MASS WILL CONTINUE TO DIURNALLY STABILIZE...
SUFFICIENT INSTABILITY REMAINS AND WHEN COMBINED WITH 30-40 KT OF
BULK SHEAR SUPPORTS A CONTINUED THREAT FOR SEVERE STORMS UNTIL ABOUT
03Z.
..PETERS.. 05/04/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...DTX...IWX...GRR...
LAT...LON 41738351 41708486 41778685 42458631 42588505 43028416
43388334 43678211 43098227 42508257 42038310 41738351Nearby
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.