Alert archive / Indiana / Mesoscale Discussions in 2021

Mesoscale Discussion 1022

June 19, 202136 counties in Indiana; 7 counties in Michigan; 10 counties in Ohio

The Storm Prediction Center issued this mesoscale discussion at Jun 19, 2021, 8:14 PM EDT for 36 counties in Indiana; 7 counties in Michigan; 10 counties in Ohio. It was in force for 91 min.

The area

The outline as issued.

The facts

Issued
Jun 19, 2021, 8:14 PM EDT (00:14 UTC)
Expired
Jun 19, 2021, 9:45 PM EDT
In force
91 min
Issued by
the Storm Prediction Center
Concerning
Severe potential...watch possible
Chance of a watch
40%
All 53 counties

Adams County, IN, Allen County, IN, Blackford County, IN, Carroll County, IN, Cass County, IN, Clinton County, IN, DeKalb County, IN, Delaware County, IN, Elkhart County, IN, Fulton County, IN, Grant County, IN, Hamilton County, IN, Henry County, IN, Howard County, IN, Huntington County, IN, Jay County, IN, Kosciusko County, IN, LaGrange County, IN, Lake County, IN, LaPorte County, IN, Madison County, IN, Marshall County, IN, Miami County, IN, Noble County, IN, Porter County, IN, Pulaski County, IN, Randolph County, IN, Saint Joseph County, IN, Starke County, IN, Steuben County, IN, Tipton County, IN, Wabash County, IN, Wayne County, IN, Wells County, IN, White County, IN, Whitley County, IN, Berrien County, MI, Branch County, MI, Calhoun County, MI, Cass County, MI, Hillsdale County, MI, Kalamazoo County, MI, Saint Joseph County, MI, Allen County, OH, Auglaize County, OH, Darke County, OH, Defiance County, OH, Mercer County, OH, Paulding County, OH, Putnam County, OH, Shelby County, OH, Van Wert County, OH, Williams County, OH

The radar

The Northern Indiana radar (KIWX), 14 km from the middle of the area, began a volume at 00:18 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 watches that followed

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

The nearest sounding before it

Detroit, MI (KDTX), launched 00:00Z, 0.2 hours before the alert went out and 254 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 2021-06-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 36 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 2021-06-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 160 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
36 J/kg
Mixed-layer CIN
-214 J/kg
Mixed-layer LCL
969 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
160 m²/s²
0-3 km storm-relative helicity
264 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

079 
ACUS11 KWNS 200014
SWOMCD
SPC MCD 200014 
MIZ000-OHZ000-INZ000-200145-

Mesoscale Discussion 1022
NWS Storm Prediction Center Norman OK
0714 PM CDT Sat Jun 19 2021

Areas affected...southern Michigan...northeast Indiana...and
northwest Ohio

Concerning...Severe potential...Watch possible 

Valid 200014Z - 200145Z

Probability of Watch Issuance...40 percent

SUMMARY...Recent vigorous storm development along the eastern shore
of Lake Michigan may pose a risk for mainly damaging wind gusts or
severe hail this evening. Storms may continue into the first part of
the overnight across Ohio and Indiana. A weather watch is uncertain.

DISCUSSION...As of 2350 UTC, KIWX radar data showed several
strong/severe storms developing along a modified lake
breeze/stationary front across southern Michigan and northern
Indiana. Visible data shows several areas of agitated cumulus along
the front and ahead of the ongoing storms suggesting additional
development is likely. SPC mesoanalysis indicates these storms are
moving into an environment supportive of severe weather potential
with moderate buoyancy (1500-2000 J/kg of MLCAPE) and sufficient
deep-layer shear (30-40 kts) for organized updrafts. Straight but
elongated hodographs and shear vectors largely parallel to the
stationary front will favor more linear/cluster modes as increasing
storm coverage/interactions develop. Damaging winds appear to be the
greatest threat though the degree of buoyancy and some potential for
initial supercell structures may also support a threat for large
hail. Low confidence in convective evolution exists currently.
However, if a deeper cold pool can develop concurrent with an
increase in the low-level jet, damaging wind potential may increase
downstream across portions of northeast Indiana and northwest Ohio
later tonight. Convective trends will be monitored for a possible
weather watch.

..Lyons/Guyer.. 06/20/2021

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

ATTN...WFO...ILN...DTX...IWX...GRR...IND...LOT...

LAT...LON   42378615 42358513 42238456 41758419 41388411 40838404
            40388412 40018445 39758521 39848586 40318666 40698692
            40968705 41198725 41458739 41748729 41948686 42158649
            42378615

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 19, 8:50 PM EDTSevere Thunderstorm WatchSPCAdams, Allen, Cass, DeKalb, Elkhart, Fulton and 14 more3 hr
Jun 20, 11:57 AM EDTMesoscale DiscussionSPCBenton, Jasper, Lake, Newton, Warren2 hr
Jun 20, 4:25 PM EDTMesoscale DiscussionSPCBenton, Carroll, Cass, Clinton, Elkhart, Fountain and 20 more2 hr
Jun 20, 6:06 PM EDTSevere Thunderstorm WatchSPCAdams, Allen, Blackford, Boone, Carroll, Cass and 38 more7 hr

Nearby

Mesoscale Discussions in Indiana, 2021Mesoscale Discussions in Ohio, 2021Mesoscale Discussions in Michigan, 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.