Alert archive / Michigan / Mesoscale Discussions in 2012

Mesoscale Discussion 1375

July 3, 201210 counties in Michigan

The Storm Prediction Center issued this mesoscale discussion at Jul 3, 2012, 4:34 PM EDT for 10 counties in Michigan. It was in force for 86 min.

The area

The outline as issued.

The facts

Issued: Jul 3, 2012, 4:34 PM EDT (20:34 UTC)
Expired: Jul 3, 2012, 6:00 PM EDT
In force: 86 min
Issued by: the Storm Prediction Center
Chance of a watch: 20%

Counties Genesee County, MI, Lapeer County, MI, Lenawee County, MI, Livingston County, MI, Macomb County, MI, Monroe County, MI, Oakland County, MI, Saint Clair County, MI, Washtenaw County, MI, Wayne County, MI

The radar

The Detroit radar (KDTX), 20 km from the middle of the area, began a volume at 20:36 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 12:00Z, 8.6 hours before the alert went out and 21 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 745 J/kg
Mixed-layer CIN: -107 J/kg
Mixed-layer LCL: 1309 m above ground
0-6 km bulk shear: 31 kt
0-1 km storm-relative helicity: 119 m²/s²
0-3 km storm-relative helicity: 108 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.4

Open this sounding in Storm Lab

The text

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

800 
ACUS11 KWNS 032034
SWOMCD
SPC MCD 032034 
MIZ000-032200-

MESOSCALE DISCUSSION 1375
NWS STORM PREDICTION CENTER NORMAN OK
0334 PM CDT TUE JUL 03 2012

AREAS AFFECTED...SE LOWER MI

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

VALID 032034Z - 032200Z

PROBABILITY OF WATCH ISSUANCE...20 PERCENT

SUMMARY...A SEVERE THREAT WILL LIKELY PERSIST LATE THIS AFTERNOON
ACROSS SERN LOWER MI. A THREAT FOR LARGE HAIL AND WIND DAMAGE WILL
LIKELY EXIST. THE THREATS ARE EXPECTED TO BE TOO SHORT IN TIME AND
SPACE FOR THE ISSUANCE OF A WATCH.

DISCUSSION...SEVERAL SEVERE STORMS ARE ONGOING ON THE WRN SUBURBS OF
DETROIT LOCATED JUST AHEAD OF A SHORTWAVE TROUGH EVIDENT ON WATER
VAPOR IMAGERY OF THE CNTRL PART OF LOWER MI. THE STORMS ARE LOCATED
ON THE EAST SIDE OF A NORTH TO SOUTH FRONTAL BOUNDARY ON THE ERN
EDGE OF A POCKET OF MODERATE INSTABILITY WITH MESOANALYSIS
ESTIMATING MLCAPE VALUES IN THE 1000 TO 2000 J/KG RANGE. THIS
COMBINED WITH ABOUT 40 KT OF DEEP LAYER SHEAR ON THE DETROIT WSR-88D
VWP SUGGESTS THE ENVIRONMENT WILL SUPPORT SUPERCELLS. IN
ADDITION...THE 12Z SOUNDING FROM DETROIT SHOWS A STEEP LAPSE RATE
FROM JUST ABOVE THE SFC TO THE MID-LEVELS WITH -14C JUST BELOW 500
MB. THIS SHOULD BE FAVORABLE FOR LARGE HAIL AS THE CELLS MOVE SEWD
ACROSS THE DETROIT METRO OVER THE NEXT FEW HOURS. ALSO...THE STORMS
SHOULD BE CAPABLE OF PRODUCING DAMAGING WINDS DUE TO THE
UNIDIRECTIONAL WIND PROFILES EVIDENT ON FORECAST SOUNDINGS.

..BROYLES/THOMPSON.. 07/03/2012

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

ATTN...WFO...DTX...GRR...

LAT...LON   43198271 43138378 42358430 41728419 41748328 42438259
            43198271

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 2, 10:17 PM EDT	Mesoscale Discussion	SPC	Baraga, Dickinson, Gogebic, Houghton, Iron, Keweenaw and 3 more	118 min
Jul 2, 11:13 PM EDT	Severe Thunderstorm Watch	SPC	Baraga, Dickinson, Gogebic, Houghton, Iron, Keweenaw and 3 more	4 hr
Jul 3, 12:17 AM EDT	Mesoscale Discussion	SPC	Alger, Baraga, Delta, Dickinson, Gogebic, Houghton and 6 more	88 min
Jul 3, 3:24 AM EDT	Mesoscale Discussion	SPC	Antrim, Bay, Benzie, Charlevoix, Cheboygan, Chippewa and 24 more	96 min

Nearby

Mesoscale Discussions in Michigan, 2012 Every 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.