Alert archive / Illinois / Mesoscale Discussions in 2012

Mesoscale Discussion 1193

June 16, 201240 counties in Illinois; 11 counties in Missouri

The Storm Prediction Center issued this mesoscale discussion at Jun 16, 2012, 7:58 PM CDT for 40 counties in Illinois; 11 counties in Missouri. It was in force for 92 min.

The area

The outline as issued.

The facts

Issued
Jun 16, 2012, 7:58 PM CDT (00:58 UTC)
Expired
Jun 16, 2012, 9:30 PM CDT
In force
92 min
Issued by
the Storm Prediction Center
All 51 counties

Bond County, IL, Calhoun County, IL, Champaign County, IL, Christian County, IL, Clinton County, IL, Coles County, IL, DeWitt County, IL, Douglas County, IL, Effingham County, IL, Fayette County, IL, Ford County, IL, Greene County, IL, Grundy County, IL, Iroquois County, IL, Jersey County, IL, Kankakee County, IL, Kendall County, IL, LaSalle County, IL, Livingston County, IL, Logan County, IL, Macon County, IL, Macoupin County, IL, Madison County, IL, Marshall County, IL, Mason County, IL, McLean County, IL, Menard County, IL, Monroe County, IL, Montgomery County, IL, Morgan County, IL, Moultrie County, IL, Piatt County, IL, Putnam County, IL, Saint Clair County, IL, Sangamon County, IL, Scott County, IL, Shelby County, IL, Tazewell County, IL, Will County, IL, Woodford County, IL, City of Saint Louis, MO, Crawford County, MO, Franklin County, MO, Gasconade County, MO, Jefferson County, MO, Lincoln County, MO, Osage County, MO, Saint Charles County, MO, Saint Louis County, MO, Warren County, MO, Washington County, MO

The radar

The Lincoln radar (KILX), 62 km from the middle of the area, began a volume at 01:02 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 00:00Z, 1.0 hours before the alert went out and 114 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 2012-06-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1606 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 2012-06-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 84 square meters per square second.1939Sfc1 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
1606 J/kg
Mixed-layer CIN
-17 J/kg
Mixed-layer LCL
1612 m above ground
0-6 km bulk shear
29 kt
0-1 km storm-relative helicity
84 m²/s²
0-3 km storm-relative helicity
93 m²/s²
Significant tornado parameter
0.1
Supercell composite
2.7

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

826 
ACUS11 KWNS 170059
SWOMCD
SPC MCD 170058
INZ000-ILZ000-MOZ000-170230-

MESOSCALE DISCUSSION 1193
NWS STORM PREDICTION CENTER NORMAN OK
0758 PM CDT SAT JUN 16 2012

AREAS AFFECTED...NRN AND CNTRL IL INTO E CNTRL MO

CONCERNING...SEVERE THUNDERSTORM WATCH 401...402...

VALID 170058Z - 170230Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH
401...402...CONTINUES.

SUMMARY...IT IS NOT CERTAIN THAT ANOTHER WW WILL BE NEEDED
SOUTH/EAST OF WWS 401 AND 402...BUT TRENDS WILL CONTINUE TO BE
MONITORED FOR THE POSSIBILITY OF A CONTINUING/INCREASING SEVERE
THREAT THAT MAY REQUIRE ONE.

DISCUSSION...AS A SURFACE CYCLONE DEEPENS OVER NORTHWEST
ONTARIO...MODEST SOUTHERLY 850 MB JET STRENGTHENING IS FORECAST
AHEAD OF A TRAILING SURFACE FRONT...WITH 30+ KTS BECOMING MORE
PROMINENT AS LEAST AS FAR SOUTH AS NORTHERN ILLINOIS.  VARIABILITY
EXISTS AMONG THE MODEL GUIDANCE CONCERNING THE STRENGTH OF THE LOWER
FLOW FIELDS FARTHER SOUTH...INTO THE MIDDLE MISSISSIPPI VALLEY.  AND
THIS WILL IMPACT THE EXTENT OF THE CONTINUING SEVERE RISK THIS
EVENING...AS THE BOUNDARY LAYER AHEAD OF THE STILL EVOLVING
MESOSCALE CONVECTIVE SYSTEM SLOWLY BEGINS TO STABILIZE WITH
RADIATIONAL SURFACE COOLING.  BUT CLOUD TOPS HAVE BEEN COOLING WITH
CONSOLIDATING STORMS OVER CENTRAL MISSOURI...WHICH COULD BEGIN
IMPACTING THE ST. LOUIS METROPOLITAN AREA DURING THE 02-04Z TIME
FRAME.

..KERR.. 06/17/2012

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

ATTN...WFO...LOT...ILX...LSX...DVN...SGF...

LAT...LON   38529206 38829174 39079099 40079013 40508989 40938951
            41668915 41808786 41648751 40648775 39468819 38838869
            38039027 37699162 38529206

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 16, 8:23 PM CDTSevere Thunderstorm WatchSPCBond, Calhoun, Cass, Champaign, Christian, Clark and 38 more3 hr
Jun 16, 10:30 PM CDTMesoscale DiscussionSPCBond, Champaign, Christian, Clark, Clay, Clinton and 26 more90 min
Jun 17, 5:34 PM CDTMesoscale DiscussionSPCCalhoun, Jersey86 min
Jun 16, 11:03 PM CDTMesoscale DiscussionSPCBenton, Camden, Dallas, Dent, Henry, Hickory and 7 more87 min
Jun 17, 2:54 AM CDTMesoscale DiscussionSPCBarton, Cedar, Dade, Polk, Vernon3 hr

Nearby

Mesoscale Discussions in Illinois, 2012Mesoscale Discussions in Missouri, 2012Every mesoscale discussion in 2012

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.