Alert archive / Michigan / Mesoscale Discussions in 2017

Mesoscale Discussion 1007

June 13, 20179 counties in Michigan

The Storm Prediction Center issued this mesoscale discussion at Jun 13, 2017, 12:58 AM EDT for 9 counties in Michigan. It was in force for 92 min.

The area

The outline as issued.

The facts

Issued
Jun 13, 2017, 12:58 AM EDT (04:58 UTC)
Expired
Jun 13, 2017, 2:30 AM EDT
In force
92 min
Issued by
the Storm Prediction Center

Counties Alcona County, MI, Alpena County, MI, Crawford County, MI, Gladwin County, MI, Iosco County, MI, Montmorency County, MI, Ogemaw County, MI, Oscoda County, MI, Roscommon County, MI

The radar

The NCL Michigan radar (KAPX), 72 km from the middle of the area, began a volume at 05:01 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 00:00Z, 5.0 hours before the alert went out and 140 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 00:00Z on 2017-06-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 577 joules per kilogram.LCLLFCEL10008507005003002001001 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 00:00Z on 2017-06-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 24 square meters per square second.193958Sfc1 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
577 J/kg
Mixed-layer CIN
-128 J/kg
Mixed-layer LCL
961 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
24 m²/s²
0-3 km storm-relative helicity
43 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.6

Open this sounding in Storm Lab

The text

As transmitted.

617 
ACUS11 KWNS 130459
SWOMCD
SPC MCD 130458 
MIZ000-130630-

Mesoscale Discussion 1007
NWS Storm Prediction Center Norman OK
1158 PM CDT Mon Jun 12 2017

Areas affected...Northeast Lower Michigan

Concerning...Severe Thunderstorm Watch 321...

Valid 130458Z - 130630Z

The severe weather threat for Severe Thunderstorm Watch 321
continues.

SUMMARY...The severe-weather threat continues across northeast Lower
Michigan as a band of storms advances to the east at 40 kt.  The
severe-weather threat has ended across the northwest part of WW 321
as storms have moved into northeast Lower Michigan, while farther
south a more stable environment precluded storms in central parts of
Lower Michigan.

DISCUSSION...At 0445Z, mosaic radar imagery indicated a short band
of storms advancing east across northeast Lower Michigan at 40 kt,
with this activity expected to move east of the Lake Huron shore
around 06Z.  These storms will move along an instability gradient
posing a continued threat for strong/damaging wind gusts.

..Peters.. 06/13/2017

...Please see www.spc.noaa.gov for graphic product...

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

LAT...LON   43958458 44598491 44968454 45168410 45138322 44548318
            44278323 44078363 43958458

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 12, 9:09 PM EDTSevere Thunderstorm WatchSPCAlcona, Antrim, Arenac, Bay, Benzie, Charlevoix and 34 more5 hr
Jun 12, 10:30 PM EDTMesoscale DiscussionSPCAlcona, Arenac, Bay, Benzie, Clare, Clinton and 29 more90 min

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.