Alert archive / Illinois / Mesoscale Discussions in 2012

Mesoscale Discussion 433

April 3, 201235 counties in Illinois; 5 counties in Indiana; 7 counties in Missouri

The Storm Prediction Center issued this mesoscale discussion at Apr 3, 2012, 2:17 PM CDT for 35 counties in Illinois; 5 counties in Indiana; 7 counties in Missouri. It was in force for 88 min.

The area

The outline as issued.

The facts

Issued
Apr 3, 2012, 2:17 PM CDT (19:17 UTC)
Expired
Apr 3, 2012, 3:45 PM CDT
In force
88 min
Issued by
the Storm Prediction Center
All 47 counties

Adams County, IL, Brown County, IL, Cass County, IL, Champaign County, IL, DeWitt County, IL, Douglas County, IL, Edgar County, IL, Ford County, IL, Fulton County, IL, Grundy County, IL, Hancock County, IL, Iroquois County, IL, Kankakee County, IL, Knox County, IL, LaSalle County, IL, Livingston County, IL, Logan County, IL, Macon County, IL, Marshall County, IL, Mason County, IL, McDonough County, IL, McLean County, IL, Menard County, IL, Morgan County, IL, Peoria County, IL, Piatt County, IL, Pike County, IL, Putnam County, IL, Schuyler County, IL, Scott County, IL, Stark County, IL, Tazewell County, IL, Vermilion County, IL, Warren County, IL, Woodford County, IL, Benton County, IN, Fountain County, IN, Newton County, IN, Vermillion County, IN, Warren County, IN, Audrain County, MO, Callaway County, MO, Lincoln County, MO, Marion County, MO, Montgomery County, MO, Pike County, MO, Ralls County, MO

The radar

The Lincoln radar (KILX), 26 km from the middle of the area, began a volume at 19:17 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 12:00Z, 7.3 hours before the alert went out and 88 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 2012-04-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 624 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 2012-04-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -115 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
624 J/kg
Mixed-layer CIN
-245 J/kg
Mixed-layer LCL
1530 m above ground
0-6 km bulk shear
6 kt
0-1 km storm-relative helicity
-115 m²/s²
0-3 km storm-relative helicity
-68 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

346 
ACUS11 KWNS 031918
SWOMCD
SPC MCD 031917
INZ000-ILZ000-MOZ000-032045-

MESOSCALE DISCUSSION 0433
NWS STORM PREDICTION CENTER NORMAN OK
0217 PM CDT TUE APR 03 2012

AREAS AFFECTED...NERN MO...CNTRL IL...FAR WRN IND

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 031917Z - 032045Z

LARGE HAIL AND DAMAGING WIND GUSTS WILL BE POSSIBLE WITH STORMS
FORMING THIS AFTERNOON/EVENING OVER NERN MO...CNTRL IL AND FAR WRN
IND. TRENDS WILL CONTINUE TO BE MONITORED FOR POSSIBLE WW.

SURFACE ANALYSIS AT 18-19Z PLACED AN AREA OF LOW PRESSURE OVER NRN
PORTIONS OF CNTRL IL...WITH A COLD FRONT EXTENDING SWWD INTO CNTRL
MO AND A WARM FRONT LOCATED SEWD INTO ERN IL AND SRN IND. WARM
SECTOR AIRMASS BETWEEN THESE TWO FRONTS IS CHARACTERIZED BY
TEMPERATURES IN THE 80S AND DEWPOINTS FROM THE MID/UPR 50S TO LOW
60S. RUC OBJECTIVE ANALYSIS GUIDANCE ALSO SHOWS THE PRESENCE OF
STEEP 700-500 MB LAPSE RATES /FROM 7 TO 8 C PER KM/...WHICH WILL AID
IN MLCAPE VALUES NEAR 1500 J/KG WITH A FEW MORE HRS OF SURFACE
HEATING. UPSTREAM FROM THE REGION...A MIDLEVEL VORTICITY LOBE IS
MOVING NEWD ACROSS CNTRL MO. LARGE-SCALE ASCENT ASSOCIATED WITH THIS
FEATURE COMBINED WITH CONVERGENCE AND DESTABILIZATION ALONG BOTH THE
COLD AND WARM FRONTAL BOUNDARIES SHOULD AID IN SCATTERED
THUNDERSTORM DEVELOPMENT BY 20-22Z. AREA VWP/S AND RUC SOUNDINGS
INDICATE VERTICAL SHEAR PROFILES WILL BE MARGINALLY SUPPORTIVE FOR
ORGANIZED MULTICELL CLUSTERS AND LINE SEGMENTS. HOWEVER...THE
MODERATE CAPE/STEEP LAPSE RATE ENVIRONMENT WILL SUPPORT A THREAT FOR
LARGE HAIL AND DAMAGING WIND GUSTS.

..GARNER.. 04/03/2012

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

ATTN...WFO...IWX...IND...LOT...ILX...LSX...DVN...

LAT...LON   41388997 41368766 40318690 39558738 39828965 38739148
            38829239 40409134 41388997

Nearby

Mesoscale Discussions in Illinois, 2012Mesoscale Discussions in Missouri, 2012Mesoscale Discussions in Indiana, 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.