Alert archive / Illinois / Mesoscale Discussions in 2016

Mesoscale Discussion 927

June 14, 201613 counties in Illinois

The Storm Prediction Center issued this mesoscale discussion at Jun 14, 2016, 7:18 PM CDT for 13 counties in Illinois. It was in force for 117 min.

The area

The outline as issued.

The facts

Issued
Jun 14, 2016, 7:18 PM CDT (00:18 UTC)
Expired
Jun 14, 2016, 9:15 PM CDT
In force
117 min
Issued by
the Storm Prediction Center
Chance of a watch
20%

Counties Christian County, IL, Clay County, IL, DeWitt County, IL, Effingham County, IL, Fayette County, IL, Logan County, IL, Macon County, IL, Marshall County, IL, Moultrie County, IL, Peoria County, IL, Shelby County, IL, Tazewell County, IL, Woodford County, IL

The radar

The Lincoln radar (KILX), 28 km from the middle of the area, began a volume at 00:19 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

Lincoln, IL (KILX), launched 00:00Z, 0.3 hours before the alert went out and 59 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 00:00Z on 2016-06-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 952 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 00:00Z on 2016-06-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 28 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
952 J/kg
Mixed-layer CIN
-8 J/kg
Mixed-layer LCL
1379 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
28 m²/s²
0-3 km storm-relative helicity
58 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.6

Open this sounding in Storm Lab

The text

As transmitted.

967 
ACUS11 KWNS 150019
SWOMCD
SPC MCD 150018 
ILZ000-150215-

MESOSCALE DISCUSSION 0927
NWS STORM PREDICTION CENTER NORMAN OK
0718 PM CDT TUE JUN 14 2016

AREAS AFFECTED...PORTIONS OF CNTRL IL

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

VALID 150018Z - 150215Z

PROBABILITY OF WATCH ISSUANCE...20 PERCENT

SUMMARY...A RISK FOR STRONG TSTMS WILL AFFECT PORTIONS OF CNTRL IL
INTO THE EVENING HOURS. WHILE CONVECTIVE TRENDS WILL CONTINUE TO BE
MONITORED...WW ISSUANCE IS PRESENTLY UNLIKELY.

DISCUSSION...A QUASI-STATIONARY FRONTAL ZONE ORIENTED NNW-SSE
THROUGH PARTS OF CNTRL IL WILL BE A FOCUS FOR ISOLATED TO SCATTERED
TSTM DEVELOPMENT THROUGH THE EVENING HOURS. CONVECTION GENERATING ON
THE WARM SIDE OF THIS ZONE WILL TEND TO ADVANCE INTO THE MODESTLY
COOLER AIR...AND SOME INCREASE IN THIS CONVECTION MAY OCCUR GIVEN
ASCENT RELATED TO A GLANCING/SUBTLE MID-LEVEL PERTURBATION PER WATER
VAPOR LOOPS. HOWEVER...AIR ON THE COOLER SIDE OF THIS BOUNDARY
FEATURES SFC TEMPERATURES IN THE UPPER 70S AMIDST DEWPOINTS IN THE
LOWER 70S SUPPORTING SUFFICIENT BUOYANCY FOR MAINTAINED CONVECTION
AMIDST BACKED SFC WINDS. MODEST AMBIENT VERTICAL VORTICITY IN
PROXIMITY TO THE FRONTAL ZONE...WITH SUFFICIENT LOW-LEVEL SRH ON ITS
COOLER SIDE...MAY SUPPORT A BRIEF/WEAK TORNADO WITH SUSTAINED
CONVECTION. ISOLATED STRONG TO PERHAPS DMGG WIND GUSTS CANNOT BE
RULED OUT. HOWEVER...GIVEN POOR MID-LEVEL LAPSE RATES/WEAK LOW-LEVEL
FLOW/MODEST DEEP SHEAR SAMPLED BY THE 00Z ILX RAOB...THE SVR RISK IS
PRESENTLY EXPECTED TO BE TOO MARGINAL FOR WW ISSUANCE.

..COHEN/CORFIDI.. 06/15/2016

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...PAH...LOT...ILX...LSX...

LAT...LON   40808990 41128975 41008903 39698864 38758822 38528869
            38908924 39638960 40808990

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 14, 8:36 PM CDTMesoscale DiscussionSPCCarroll, Jo Daviess, Whiteside84 min
Jun 14, 11:27 PM CDTMesoscale DiscussionSPCDeKalb, Kane, Kendall, LaSalle, Lee, Ogle93 min
Jun 15, 12:05 PM CDTMesoscale DiscussionSPCAlexander, Gallatin, Hardin, Johnson, Massac, Pope and 3 more85 min
Jun 15, 12:39 PM CDTSevere Thunderstorm WatchSPCAlexander, Edwards, Franklin, Gallatin, Hamilton, Hardin and 10 more8 hr
Jun 15, 2:23 PM CDTMesoscale DiscussionSPCChampaign, Christian, Clark, Coles, Cumberland, Douglas and 6 more97 min
Jun 15, 3:00 PM CDTSevere Thunderstorm WatchSPCClark, Clay, Coles, Crawford, Cumberland, Douglas and 9 more5 hr
Jun 15, 6:01 PM CDTMesoscale DiscussionSPCWabash59 min

Nearby

Mesoscale Discussions in Illinois, 2016Every mesoscale discussion in 2016

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.