Alert archive / Michigan / Mesoscale Discussions in 2012

Mesoscale Discussion 1209

June 18, 201218 counties in Michigan; Door County, Kewaunee County, Wisconsin

The Storm Prediction Center issued this mesoscale discussion at Jun 18, 2012, 4:50 PM EDT for 18 counties in Michigan; Door County, Kewaunee County, Wisconsin. It was in force for 85 min.

The area

The outline as issued.

The facts

Issued
Jun 18, 2012, 4:50 PM EDT (20:50 UTC)
Expired
Jun 18, 2012, 6:15 PM EDT
In force
85 min
Issued by
the Storm Prediction Center

Counties Antrim County, MI, Benzie County, MI, Charlevoix County, MI, Cheboygan County, MI, Crawford County, MI, Emmet County, MI, Grand Traverse County, MI, Kalkaska County, MI, Lake County, MI, Leelanau County, MI, Manistee County, MI, Mason County, MI, Missaukee County, MI, Montmorency County, MI, Oscoda County, MI, Otsego County, MI, Presque Isle County, MI, Wexford County, MI, Door County, WI, Kewaunee County, WI

The radar

The NCL Michigan radar (KAPX), 39 km from the middle of the area, began a volume at 20:51 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Alpena, MI (KAPX), launched 12:00Z, 8.8 hours before the alert went out and 221 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-pSkew-T log-p diagram, Alpena, MI at 12:00Z on 2012-06-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Alpena, MI at 12:00Z on 2012-06-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 80 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1609 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
80 m²/s²
0-3 km storm-relative helicity
164 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

676 
ACUS11 KWNS 182051
SWOMCD
SPC MCD 182050
MIZ000-WIZ000-182215-

MESOSCALE DISCUSSION 1209
NWS STORM PREDICTION CENTER NORMAN OK
0350 PM CDT MON JUN 18 2012

AREAS AFFECTED...ERN UPPER/NRN LOWER MI

CONCERNING...SEVERE THUNDERSTORM WATCH 406...

VALID 182050Z - 182215Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 406
CONTINUES.

SUMMARY...DOWNSTREAM WW ISSUANCE WILL BE CONSIDERED IN THE NEXT
COUPLE OF HOURS AS MCS OVER NERN WI/ERN UPPER MI IS EXTRAPOLATED TO
REACH NRN LOWER MI BETWEEN 23-00Z.

DISCUSSION...IN THE WAKE OF EARLIER CONVECTIVE DEBRIS...NEARLY
CLOUD-FREE SKIES HAS RESULTED IN STRONG HEATING WITH TEMPERATURES
WARMING GENERALLY THROUGH THE 80S IN LOWER MI. ALTHOUGH BUOYANCY IS
LIKELY NOT AS GREAT AS W OF LK MI GIVEN THE OVERTURNING EARLIER THIS
MORNING...CONTINUED HEATING MAY SUPPORT ONGOING ACTIVITY BEING
SUSTAINED AS IT CROSS THE LK INTO NRN LOWER MI. PRIMARY RISK SHOULD
BE DAMAGING WIND AS STRONG UNIDIRECTIONAL DEEP-LAYER SHEAR MAY YIELD
BOWING LINE SEGMENTS.

..GRAMS.. 06/18/2012

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

ATTN...WFO...APX...GRR...GRB...

LAT...LON   44478762 45198712 46008573 46298443 46158369 45848335
            45488318 45068326 44728364 44498412 44368457 43978585
            43928658 44178734 44478762

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 18, 10:33 AM EDTMesoscale DiscussionSPCBranch, Calhoun, Eaton, Genesee, Hillsdale, Ingham and 13 more2 hr
Jun 18, 12:40 PM EDTMesoscale DiscussionSPCDelta, Menominee2 hr
Jun 18, 1:24 PM EDTSevere Thunderstorm WatchSPCDelta, Dickinson, Iron, Menominee, Schoolcraft8 hr
Jun 18, 1:38 PM EDTMesoscale DiscussionSPCMonroe67 min
Jun 18, 5:46 PM EDTSevere Thunderstorm WatchSPCAlcona, Alpena, Antrim, Arenac, Benzie, Charlevoix and 25 more6 hr
Jun 17, 8:27 PM EDTMesoscale DiscussionSPCPierce, Polk, Saint Croix93 min
Jun 17, 8:57 PM EDTSevere Thunderstorm WatchSPCAdams, Barron, Buffalo, Burnett, Chippewa, Clark and 21 more8 hr
Jun 17, 11:55 PM EDTMesoscale DiscussionSPCBuffalo, La Crosse, Pierce, Trempealeau95 min
Jun 18, 2:28 AM EDTMesoscale DiscussionSPCAdams, Buffalo, Chippewa, Clark, Columbia, Dunn and 22 more62 min
Jun 18, 3:49 PM EDTMesoscale DiscussionSPCBrown, Calumet, Kewaunee, Marinette, Menominee, Oconto and 5 more86 min
Jun 18, 7:00 PM EDTMesoscale DiscussionSPCBrown, Calumet, Door, Green Lake, Kewaunee, Manitowoc and 7 more60 min

Nearby

Mesoscale Discussions in Michigan, 2012Mesoscale Discussions in Wisconsin, 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.