Alert archive / Michigan / Mesoscale Discussions in 2017
Mesoscale Discussion 34
The Storm Prediction Center issued this mesoscale discussion at Jan 11, 2017, 7:32 PM EST for 21 counties in Michigan. It was in force for 6 hr.
The area
The outline as issued.
The facts
- Issued
- Jan 11, 2017, 7:32 PM EST (00:32 UTC)
- Expired
- Jan 12, 2017, 1:30 AM EST
- In force
- 6 hr
- Issued by
- the Storm Prediction Center
All 21 counties
Alcona County, MI, Alpena County, MI, Arenac County, MI, Bay County, MI, Clare County, MI, Crawford County, MI, Gladwin County, MI, Iosco County, MI, Isabella County, MI, Lake County, MI, Mecosta County, MI, Midland County, MI, Missaukee County, MI, Montcalm County, MI, Muskegon County, MI, Newaygo County, MI, Oceana County, MI, Ogemaw County, MI, Osceola County, MI, Oscoda County, MI, Roscommon County, MI
The radar
The NCL Michigan radar (KAPX), 103 km from the middle of the area, began a volume at 00:31 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, 0.5 hours before the alert went out and 171 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 439 m above ground
- 0-6 km bulk shear
- 82 kt
- 0-1 km storm-relative helicity
- 644 m²/s²
- 0-3 km storm-relative helicity
- 707 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.0
The text
As transmitted.
779
ACUS11 KWNS 120033
SWOMCD
SPC MCD 120032
MIZ000-120630-
Mesoscale Discussion 0034
NWS Storm Prediction Center Norman OK
0632 PM CST Wed Jan 11 2017
Areas affected...Portions of northern and central Lower Michigan
Concerning...Winter mixed precipitation
Valid 120032Z - 120630Z
SUMMARY...Rain and snow will continue to transition to freezing rain
and sleet, possibly with snow mixed in at times tonight. Freezing
rain rates will generally be a couple hundredths a hour, for several
hours tonight.
DISCUSSION...Areas of rain and snow have begun to transition to
freezing rain and sleet across the MCD area, most recently noted at
CAD. Low level cold advection behind a surface cold front will
allow temperatures to fall below freezing over the next few hours,
and wet-bulb temperatures near to below freezing have shifted
southward over the last hour per 00z mesoanalysis. RAP forecast
soundings indicate a warm layer between 850-700mb from about 0-2
degrees C with a sub-freezing layer below this about 1000-2000 ft
thick. This will support freezing rain and sleet across a relatively
narrow corridor across portions of northern/central Lower Michigan.
Hi-res guidance suggest this swatch of frozen precip will persist
and shift slightly southward with time through at least 06z. Some
areas may see a brief change to snow toward the end of the event as
stronger midlevel cold advection spreads over the area later
tonight, and before precipitation comes to an end.
..Leitman.. 01/12/2017
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...DTX...APX...GRR...
LAT...LON 44318298 43738371 43458446 43178558 43108631 43238657
43468662 43828668 44828443 44958359 44878326 44618294
44318298SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jan 12, 4:05 AM EST | Mesoscale Discussion | SPC | Barry, Berrien, Branch, Calhoun, Cass, Eaton and 8 more | 6 hr |
Nearby
Mesoscale Discussions in Michigan, 2017Every mesoscale discussion in 2017
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.