Alert archive / Illinois / Mesoscale Discussions in 2018

Mesoscale Discussion 697

June 10, 201826 counties in Illinois; 21 counties in Indiana

The Storm Prediction Center issued this mesoscale discussion at Jun 10, 2018, 2:42 PM CDT for 26 counties in Illinois; 21 counties in Indiana. It was in force for 93 min.

The area

The outline as issued.

The facts

Issued
Jun 10, 2018, 2:42 PM CDT (19:42 UTC)
Expired
Jun 10, 2018, 4:15 PM CDT
In force
93 min
Issued by
the Storm Prediction Center
All 47 counties

Champaign County, IL, Christian County, IL, Clark County, IL, Clay County, IL, Coles County, IL, Crawford County, IL, Cumberland County, IL, DeWitt County, IL, Douglas County, IL, Edgar County, IL, Effingham County, IL, Fayette County, IL, Ford County, IL, Jasper County, IL, Lawrence County, IL, Logan County, IL, Macon County, IL, McLean County, IL, Menard County, IL, Montgomery County, IL, Moultrie County, IL, Piatt County, IL, Richland County, IL, Sangamon County, IL, Shelby County, IL, Vermilion County, IL, Benton County, IN, Boone County, IN, Clay County, IN, Daviess County, IN, Fountain County, IN, Greene County, IN, Hendricks County, IN, Knox County, IN, Lawrence County, IN, Martin County, IN, Monroe County, IN, Montgomery County, IN, Morgan County, IN, Owen County, IN, Parke County, IN, Putnam County, IN, Sullivan County, IN, Tippecanoe County, IN, Vermillion County, IN, Vigo County, IN, Warren County, IN

The radar

The Lincoln radar (KILX), 134 km from the middle of the area, began a volume at 19:41 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

Lincoln, IL (KILX), launched 12:00Z, 7.7 hours before the alert went out and 87 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, Lincoln, IL at 12:00Z on 2018-06-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 585 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, Lincoln, IL at 12:00Z on 2018-06-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 362 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
585 J/kg
Mixed-layer CIN
-193 J/kg
Mixed-layer LCL
611 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
362 m²/s²
0-3 km storm-relative helicity
382 m²/s²
Significant tornado parameter
0.0
Supercell composite
6.2

Open this sounding in Storm Lab

The text

As transmitted.

150 
ACUS11 KWNS 101942
SWOMCD
SPC MCD 101942 
INZ000-ILZ000-102115-

Mesoscale Discussion 0697
NWS Storm Prediction Center Norman OK
0242 PM CDT Sun Jun 10 2018

Areas affected...East-Central IL...West-Central IN

Concerning...Severe Thunderstorm Watch 168...

Valid 101942Z - 102115Z

The severe weather threat for Severe Thunderstorm Watch 168
continues.

SUMMARY...Threat for damaging wind gusts and perhaps a tornado or
two continues across east-central IL. Downstream threat across
west-central IN will likely merit the issuance of another watch
soon.

DISCUSSION...MCS moving across central IL has recently exhibited an
increase in forward motion, likely as a result of increased forward
propagation into the warm, moist, and inhibition-free airmass
downstream. New storm development as also occurred ahead of the
line, increasing the probability for continued forward propagation.
Current storm motion is estimated as 310 degrees at 35 kt. Northern
portion of the line appears to be moving a little faster (i.e.
closer to 40 kt). This southeastward progression will likely take
the northern portion of the line to the edge of Severe Thunderstorm
Watch 168 by 20Z. Downstream airmass across west-central/southern IN
remains favorable for continued MCS progression and downstream watch
will likely be needed soon.

One other item of note is the increased southeasterly winds in place
immediately along the warm front draped from near CMI southward into
far southwest IN. Resulting localized enhancement of the low-level
shear may contribute to brief tornado potential.

..Mosier/Grams.. 06/10/2018

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

ATTN...WFO...IND...LOT...ILX...LSX...

LAT...LON   40108999 40648848 40668734 40258643 39168623 38728650
            38608719 38628771 38758858 39118956 40108999

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 9, 7:43 PM CDTSevere Thunderstorm WatchSPCBureau, Carroll, Henry, Jo Daviess, Lee, Ogle and 5 more6 hr
Jun 9, 10:17 PM CDTMesoscale DiscussionSPCBoone, Bureau, Carroll, Henry, Jo Daviess, LaSalle and 8 more118 min
Jun 9, 11:44 PM CDTMesoscale DiscussionSPCBoone, Bureau, Carroll, Henry, Jo Daviess, LaSalle and 8 more2 hr
Jun 10, 10:04 AM CDTMesoscale DiscussionSPCBond, Cass, Champaign, Christian, Clark, Clay and 43 more116 min
Jun 10, 12:17 PM CDTMesoscale DiscussionSPCBond, Brown, Cass, Christian, Clark, Clay and 34 more118 min
Jun 10, 12:46 PM CDTSevere Thunderstorm WatchSPCCass, Champaign, Christian, Clark, Clay, Coles and 29 more7 hr
Jun 10, 2:56 PM CDTSevere Thunderstorm WatchSPCEdwards, Wabash, Wayne, White5 hr
Jun 10, 4:30 PM CDTMesoscale DiscussionSPCAdams, Brown, Calhoun, Greene, Jersey, Macoupin and 3 more90 min
Jun 10, 5:20 PM CDTMesoscale DiscussionSPCEdwards, Lawrence, Wabash, Wayne, White85 min

Nearby

Mesoscale Discussions in Illinois, 2018Mesoscale Discussions in Indiana, 2018Every mesoscale discussion in 2018

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.