Alert archive / Indiana / Mesoscale Discussions in 2017

Mesoscale Discussion 233

March 1, 201734 counties in Indiana; 9 counties in Michigan; 15 counties in Ohio

The Storm Prediction Center issued this mesoscale discussion at Mar 1, 2017, 1:44 AM EST for 34 counties in Indiana; 9 counties in Michigan; 15 counties in Ohio. It was in force for 61 min.

The area

The outline as issued.

The facts

Issued
Mar 1, 2017, 1:44 AM EST (06:44 UTC)
Expired
Mar 1, 2017, 2:45 AM EST
In force
61 min
Issued by
the Storm Prediction Center
All 58 counties

Adams County, IN, Allen County, IN, Blackford County, IN, Boone County, IN, Carroll County, IN, Cass County, IN, Clinton County, IN, DeKalb County, IN, Delaware County, IN, Elkhart County, IN, Fountain County, IN, Fulton County, IN, Grant County, IN, Hamilton County, IN, Howard County, IN, Huntington County, IN, Jay County, IN, Kosciusko County, IN, LaGrange County, IN, Madison County, IN, Marshall County, IN, Miami County, IN, Montgomery County, IN, Noble County, IN, Pulaski County, IN, Randolph County, IN, Steuben County, IN, Tippecanoe County, IN, Tipton County, IN, Wabash County, IN, Warren County, IN, Wells County, IN, White County, IN, Whitley County, IN, Branch County, MI, Calhoun County, MI, Hillsdale County, MI, Jackson County, MI, Kalamazoo County, MI, Lenawee County, MI, Monroe County, MI, Saint Joseph County, MI, Washtenaw County, MI, Allen County, OH, Auglaize County, OH, Darke County, OH, Defiance County, OH, Fulton County, OH, Hancock County, OH, Henry County, OH, Lucas County, OH, Mercer County, OH, Paulding County, OH, Putnam County, OH, Shelby County, OH, Van Wert County, OH, Williams County, OH, Wood County, OH

The radar

The Northern Indiana radar (KIWX), 61 km from the middle of the area, began a volume at 06:46 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

Cncnati-Daytn, OH (KILN), launched 00:00Z, 6.7 hours before the alert went out and 232 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, Cncnati-Daytn, OH at 00:00Z on 2017-03-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 126 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, Cncnati-Daytn, OH at 00:00Z on 2017-03-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 416 square meters per square second.1939587897117Sfc1 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
126 J/kg
Mixed-layer CIN
-51 J/kg
Mixed-layer LCL
490 m above ground
0-6 km bulk shear
54 kt
0-1 km storm-relative helicity
416 m²/s²
0-3 km storm-relative helicity
441 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.7

Open this sounding in Storm Lab

The text

As transmitted.

979 
ACUS11 KWNS 010644
SWOMCD
SPC MCD 010644 
OHZ000-MIZ000-INZ000-ILZ000-010745-

Mesoscale Discussion 0233
NWS Storm Prediction Center Norman OK
1244 AM CST Wed Mar 01 2017

Areas affected...Portions of southern Lower
Michigan...northeastern/central Indiana...and northwestern Ohio

Concerning...Severe Thunderstorm Watch 45...49...

Valid 010644Z - 010745Z

The severe weather threat for Severe Thunderstorm Watch 45, 49
continues.

SUMMARY...A squall line will continue advancing east across the
discussion area early this morning. An attendant threat for damaging
winds will persist as these storms track east.

DISCUSSION...With broader large-scale ascent (e.g., coupled upper
jet structure) spreading across the Great Lakes region, rejuvenation
of an ongoing squall line over southern Lower Michigan/northern
Indiana has occurred. Despite some surface-based convective
inhibition/weak low-level stability, the upscale organization of the
line, combined with 1-km flow around 50 kts, will maintain a threat
for occasional damaging wind gusts, especially in any bowing
segments. Additionally, considering the magnitude of the low-level
shear, a brief tornado remains possible.

..Picca.. 03/01/2017

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

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

LAT...LON   40258766 41328639 42358556 42268374 41588313 40328399
            39948523 39898723 40048781 40258766

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Feb 28, 7:00 PM ESTMesoscale DiscussionSPCAdams, Allen, Cass, DeKalb, Elkhart, Fulton and 14 more90 min
Feb 28, 7:37 PM ESTSevere Thunderstorm WatchSPCAllen, DeKalb, Elkhart, Fulton, Kosciusko, LaGrange and 8 more8 hr
Feb 28, 8:46 PM ESTMesoscale DiscussionSPCBrown, Crawford, Daviess, Dubois, Gibson, Greene and 14 more119 min
Feb 28, 9:29 PM ESTTornado WatchSPCBartholomew, Brown, Clark, Clay, Crawford, Daviess and 34 more12 hr
Feb 28, 9:41 PM ESTMesoscale DiscussionSPCAllen, DeKalb, Elkhart, Fulton, Kosciusko, LaGrange and 9 more94 min
Feb 28, 10:51 PM ESTTornado WatchSPCBenton, Jasper, Lake, Newton, Porter6 hr
Feb 28, 11:03 PM ESTMesoscale DiscussionSPCAdams, Allen, Bartholomew, Blackford, Boone, Carroll and 48 more117 min
Feb 28, 11:09 PM ESTMesoscale DiscussionSPCCrawford, Daviess, Dubois, Gibson, Knox, Lawrence and 6 more66 min
Feb 28, 11:29 PM ESTTornado WatchSPCAdams, Allen, Blackford, Boone, Carroll, Cass and 41 more8 hr
Mar 1, 12:52 AM ESTMesoscale DiscussionSPCBenton, Elkhart, Fulton, Jasper, LaPorte, Marshall and 7 more53 min
Mar 1, 2:32 AM ESTMesoscale DiscussionSPCClark, Crawford, Dearborn, Dubois, Floyd, Harrison and 11 more88 min
Mar 1, 4:03 AM ESTTornado WatchSPCGibson, Pike, Posey, Spencer, Vanderburgh, Warrick5 hr
Mar 1, 5:19 AM ESTMesoscale DiscussionSPCHarrison, Perry, Posey, Spencer, Vanderburgh, Warrick56 min
Mar 1, 5:57 AM ESTTornado WatchSPCClark, Crawford, Dearborn, Dubois, Floyd, Franklin and 9 more5 hr
Mar 1, 2:19 AM ESTMesoscale DiscussionSPCAshland, Ashtabula, Belmont, Carroll, Columbiana, Coshocton and 22 more86 min
Mar 1, 3:24 AM ESTSevere Thunderstorm WatchSPCAshland, Ashtabula, Crawford, Cuyahoga, Erie, Geauga and 22 more4 hr
Mar 1, 6:28 AM ESTMesoscale DiscussionSPCAdams, Gallia, Lawrence, Scioto2 hr
Mar 1, 6:48 AM ESTSevere Thunderstorm WatchSPCAthens, Gallia, Jackson, Lawrence, Meigs, Morgan and 3 more5 hr
Mar 1, 8:28 AM ESTMesoscale DiscussionSPCGallia, Lawrence92 min
Mar 1, 3:56 PM ESTMesoscale DiscussionSPCAthens, Belmont, Carroll, Columbiana, Coshocton, Fairfield and 26 more2 hr

Nearby

Mesoscale Discussions in Indiana, 2017Mesoscale Discussions in Ohio, 2017Mesoscale 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.