Alert archive / Michigan / Mesoscale Discussions in 2012
Mesoscale Discussion 1895
The Storm Prediction Center issued this mesoscale discussion at Sep 5, 2012, 4:45 PM EDT for 20 counties in Michigan. It was in force for 90 min.
The area
The outline as issued.
The facts
- Issued
- Sep 5, 2012, 4:45 PM EDT (20:45 UTC)
- Expired
- Sep 5, 2012, 6:15 PM EDT
- In force
- 90 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 40%
Counties Alcona County, MI, Alpena County, MI, Antrim County, MI, Arenac County, MI, Cheboygan County, MI, Chippewa County, MI, Clare County, MI, Crawford County, MI, Gladwin County, MI, Iosco County, MI, Kalkaska County, MI, Missaukee County, MI, Montmorency County, MI, Ogemaw County, MI, Osceola County, MI, Oscoda County, MI, Otsego County, MI, Presque Isle County, MI, Roscommon County, MI, Wexford County, MI
The radar
The NCL Michigan radar (KAPX), 45 km from the middle of the area, began a volume at 20:48 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
Alpena, MI (KAPX), launched 12:00Z, 8.8 hours before the alert went out and 145 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
- 956 J/kg
- Mixed-layer CIN
- -54 J/kg
- Mixed-layer LCL
- 794 m above ground
- 0-6 km bulk shear
- 15 kt
- 0-1 km storm-relative helicity
- 8 m²/s²
- 0-3 km storm-relative helicity
- 37 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
401
ACUS11 KWNS 052045
SWOMCD
SPC MCD 052045
MIZ000-052215-
MESOSCALE DISCUSSION 1895
NWS STORM PREDICTION CENTER NORMAN OK
0345 PM CDT WED SEP 05 2012
AREAS AFFECTED...NRN LOWER MI...ERN UP
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 052045Z - 052215Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...AT LEAST ISOLATED STRONG TO SEVERE STORMS ARE EXPECTED TO
FORM OVER NRN LOWER MI LATER THIS AFTERNOON...BUT COVERAGE MAY BE
TOO LIMITED FOR A WATCH.
DISCUSSION...A WELL DEFINED SHORTWAVE TROUGH CONTINUES TO MOVE
ACROSS UPPER MI...WITH TAIL END EXTENDING SWD ACROSS NRN LAKE
MI...WHICH WILL PASS ACROSS NRN LOWER MI. VISIBLE IMAGERY SHOWS A
SUBSTANTIAL CU FIELD OVER NRN LOWER MI. DEWPOINTS HAVE MIXED INTO
THE UPPER 50S F OVER NWRN LOWER MI...BUT MID 60S F DEWPOINTS AND
CORRESPONDINGLY HIGHER PWAT VALUES AROUND 1.50" EXIST ACROSS THE ERN
HALF OF THE STATE. AS FORCING WITH THE SHORTWAVE INTERACTS WITH THE
UNSTABLE AIR MASS...A FEW STORMS CAPABLE OF HAIL AND WIND MAY
MATERIALIZE.
..JEWELL/CORFIDI.. 09/05/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...DTX...APX...GRR...
LAT...LON 44258296 43978346 43918387 43908481 43978572 44298575
44838533 45398488 46538473 46488393 45598314 44478295
44258296SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 4, 9:30 PM EDT | Mesoscale Discussion | SPC | Gogebic, Ontonagon | 60 min |
| Sep 5, 1:51 PM EDT | Mesoscale Discussion | SPC | Alcona, Alpena, Arenac, Bay, Genesee, Huron and 8 more | 114 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.