Alert archive / Michigan / Mesoscale Discussions in 2021

Mesoscale Discussion 1044

June 21, 202114 counties in Indiana; 20 counties in Michigan; 9 counties in Ohio

The Storm Prediction Center issued this mesoscale discussion at Jun 21, 2021, 2:14 AM EDT for 14 counties in Indiana; 20 counties in Michigan; 9 counties in Ohio. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Jun 21, 2021, 2:14 AM EDT (06:14 UTC)
Expired
Jun 21, 2021, 4:15 AM EDT
In force
2 hr
Issued by
the Storm Prediction Center
Concerning
Severe thunderstorm watch 298
All 43 counties

Allen County, IN, DeKalb County, IN, Elkhart County, IN, Fulton County, IN, Kosciusko County, IN, LaGrange County, IN, LaPorte County, IN, Marshall County, IN, Noble County, IN, Pulaski County, IN, Saint Joseph County, IN, Starke County, IN, Steuben County, IN, Whitley County, IN, Allegan County, MI, Barry County, MI, Berrien County, MI, Branch County, MI, Calhoun County, MI, Cass County, MI, Eaton County, MI, Hillsdale County, MI, Ingham County, MI, Jackson County, MI, Kalamazoo County, MI, Lenawee County, MI, Livingston County, MI, Macomb County, MI, Monroe County, MI, Oakland County, MI, Saint Joseph County, MI, Van Buren County, MI, Washtenaw County, MI, Wayne County, MI, Defiance County, OH, Fulton County, OH, Henry County, OH, Lucas County, OH, Ottawa County, OH, Paulding County, OH, Sandusky County, OH, Williams County, OH, Wood County, OH

The radar

The Detroit radar (KDTX), 124 km from the middle of the area, began a volume at 06:18 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, 6.2 hours before the alert went out and 128 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, Detroit, MI at 00:00Z on 2021-06-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 133 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, Detroit, MI at 00:00Z on 2021-06-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 52 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
133 J/kg
Mixed-layer CIN
-112 J/kg
Mixed-layer LCL
1501 m above ground
0-6 km bulk shear
41 kt
0-1 km storm-relative helicity
52 m²/s²
0-3 km storm-relative helicity
102 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted.

865 
ACUS11 KWNS 210615
SWOMCD
SPC MCD 210614 
OHZ000-MIZ000-INZ000-210815-

Mesoscale Discussion 1044
NWS Storm Prediction Center Norman OK
0114 AM CDT Mon Jun 21 2021

Areas affected...Northern Indiana...Southern Lower Michigan...Far
Northwest Ohio

Concerning...Severe Thunderstorm Watch 298...

Valid 210614Z - 210815Z

The severe weather threat for Severe Thunderstorm Watch 298
continues.

SUMMARY...A tornado and wind-damage threat is expected to continue
across parts of northern Indiana and southern Lower Michigan over
the next few hours. The threat should eventually effect northwest
Ohio.

DISCUSSION...The latest radar imagery shows a well-developed QLCS
over northwest Indiana and southwest Lower Michigan. The QLCS is
located in a very moist airmass with surface dewpoints near 70 F.
This is contributing to moderate instability ahead of the QLCS, with
the RAP analyzing MLCAPE in the 1500 to 2500 J/Kg range across
northern Indiana and northwest Ohio. In addition, the WSR-88D VWP in
South Bend, Indiana has 0-6 km shear of 30 to 35 kt with 50 kt of
flow just above the surface. This environment will continue to
support QLCS development. For this reason, the bowing line segments
ongoing in the western part of WW 298 are expected to be maintained
for several more hours. Wind damage will be likely along the leading
edge of the more intense line segments. A tornado or two will also
be possible, associated with any rotating storms embedded in the
line.

..Broyles.. 06/21/2021

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

ATTN...WFO...CLE...DTX...IWX...GRR...

LAT...LON   40898689 40898619 41058613 41008526 40908522 40938432
            41158429 41178336 41238335 41248282 41378282 41458309
            41518260 41658259 41908295 42098304 42328291 42518253
            42678265 42838268 42848364 42798369 42748629 42488635
            42418695 40898689

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 20, 8:14 PM EDTMesoscale DiscussionSPCAdams, Allen, Blackford, Boone, Carroll, Cass and 30 more61 min
Jun 20, 10:40 PM EDTSevere Thunderstorm WatchSPCBenton, Jasper, Lake, Newton, Porter4 hr
Jun 20, 11:51 PM EDTMesoscale DiscussionSPCAdams, Allen, Cass, DeKalb, Elkhart, Fulton and 14 more54 min
Jun 21, 1:00 AM EDTSevere Thunderstorm WatchSPCAllen, DeKalb, Elkhart, Fulton, Kosciusko, LaGrange and 8 more7 hr
Jun 21, 11:59 AM EDTMesoscale DiscussionSPCAshland, Ashtabula, Athens, Belmont, Carroll, Columbiana and 31 more91 min
Jun 21, 12:31 PM EDTSevere Thunderstorm WatchSPCAdams, Ashtabula, Athens, Belmont, Carroll, Columbiana and 33 more7 hr

Nearby

Mesoscale Discussions in Michigan, 2021Mesoscale Discussions in Indiana, 2021Mesoscale Discussions in Ohio, 2021Every mesoscale discussion in 2021

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.