Alert archive / Illinois / Mesoscale Discussions in 2006

Mesoscale Discussion 2012

September 22, 200630 counties in Illinois; Lake County, Newton County, Indiana

The Storm Prediction Center issued this mesoscale discussion at Sep 22, 2006, 5:37 PM CDT for 30 counties in Illinois; Lake County, Newton County, Indiana. It was in force for 113 min.

The area

The outline as issued.

The facts

Issued
Sep 22, 2006, 5:37 PM CDT (22:37 UTC)
Expired
Sep 22, 2006, 7:30 PM CDT
In force
113 min
Issued by
the Storm Prediction Center
All 32 counties

Boone County, IL, Bureau County, IL, Cook County, IL, DeKalb County, IL, DuPage County, IL, Ford County, IL, Fulton County, IL, Grundy County, IL, Henry County, IL, Iroquois County, IL, Kane County, IL, Kankakee County, IL, Kendall County, IL, Knox County, IL, Lake County, IL, LaSalle County, IL, Lee County, IL, Livingston County, IL, Marshall County, IL, McHenry County, IL, McLean County, IL, Ogle County, IL, Peoria County, IL, Putnam County, IL, Stark County, IL, Tazewell County, IL, Whiteside County, IL, Will County, IL, Winnebago County, IL, Woodford County, IL, Lake County, IN, Newton County, IN

The radar

The Chicago radar (KLOT), 44 km from the middle of the area, began a volume at 22:40 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, 10.6 hours before the alert went out and 138 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 2006-09-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2006-09-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 571 square meters per square second.1939587897Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
831 m above ground
0-6 km bulk shear
52 kt
0-1 km storm-relative helicity
571 m²/s²
0-3 km storm-relative helicity
612 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.

000 
ACUS11 KWNS 222237
SWOMCD
SPC MCD 222237 
INZ000-ILZ000-WIZ000-230030-

MESOSCALE DISCUSSION 2012
NWS STORM PREDICTION CENTER NORMAN OK
0537 PM CDT FRI SEP 22 2006

AREAS AFFECTED...NRN IL...NWRN IND AND SWRN MI

CONCERNING...TORNADO WATCH 791...

VALID 222237Z - 230030Z

CLUSTER OF SUPERCELLS WILL CONTINUE TO MOVE EWD ACROSS NRN IL...WITH
THE MOST ORGANIZED TORNADO THREAT ANTICIPATED OVER THE CHI METRO
AREA THROUGH 00Z. ELEVATED SVR HAIL THREAT MAY DEVELOP NEWD INTO
SWRN MI AND NWRN IND OVER THE NEXT SEVERAL HRS...BUT A NEW WW IS NOT
ANTICIPATED FOR THOSE AREAS ATTM. 

SURFACE ANALYSIS AND RADAR IMAGERY FROM CHICAGO INDICATES A E-W
ORIENTED BOUNDARY EXTENDING FROM NEAR ORD EWD TO JUST NORTH OF ARR.
THREE SEPARATE SUPERCELLS WILL MOVE ALONG AND JUST NORTH OF THIS
BOUNDARY. RECENT LOT VWP DATA SHOWED A STRONGLY CURVED LOW LEVEL
HODOGRAPH WITH O-1 KM SRH AROUND 350 M2/S2. THREAT FOR
TORNADOES...POSSIBLY SIGNIFICANT...WILL OCCUR WITH THESE SUPERCELLS
AS THEY MOVE EWD ALONG AND INTERACT WITH THE AFOREMENTIONED
BOUNDARY. FARTHER SOUTH MORE DISORGANIZED BROKEN LINE OF SUPERCELLS
SHOULD CONTINUE TO MOVE EWD AROUND 30 KTS IN THE PONTIAC AND
BLOOMINGTON AREAS. IN ADDITION TO ISOLATED TORNADO POTENTIAL IN THIS
AREA...STRONG MID LEVEL WINDS /STRAIGHT LINE HODOGRAPH/ WILL FAVOR
ISOLATED LEFT MOVING SUPERCELLS WITH THE THREAT FOR LARGE HAIL.
STRENGTHENING SWLY LOW LEVEL JET WILL AID IN INCREASING ELEVATED
INSTABILITY INTO NWRN IND AND SWRN MI OVER THE NEXT FEW HRS. THIS
MAY SUPPORT A MARGINAL ELEVATED SVR HAIL THREAT WITH ANY DEVELOPING
TSTMS OVER THE AREA AND/OR NRN IL SVR STORMS THAT MOVE INTO THE AREA
IN THE NEXT SEVERAL HRS.

..CROSBIE.. 09/22/2006

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

ATTN...WFO...IND...LOT...ILX...MKX...DVN...

42508756 42528922 41859015 40219068 40268979 40278832
40298738 41028738 42448724

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 22, 12:49 PM CDTMesoscale DiscussionSPCAdams, Alexander, Bond, Brown, Calhoun, Cass and 38 more2 hr
Sep 22, 1:16 PM CDTTornado WatchSPCAdams, Alexander, Bond, Brown, Calhoun, Cass and 42 more8 hr
Sep 22, 2:20 PM CDTMesoscale DiscussionSPCBoone, Bureau, Carroll, Cook, DeKalb, DuPage and 30 more2 hr
Sep 22, 2:55 PM CDTMesoscale DiscussionSPCGallatin, Hamilton, Hardin, Johnson, Massac, Pope and 2 more2 hr
Sep 22, 3:00 PM CDTMesoscale DiscussionSPCAdams, Alexander, Bond, Brown, Calhoun, Cass and 45 more90 min
Sep 22, 3:32 PM CDTTornado WatchSPCBoone, Bureau, Carroll, Cook, DeKalb, DuPage and 33 more6 hr
Sep 22, 3:37 PM CDTTornado WatchSPCEdwards, Gallatin, Hamilton, Hardin, Massac, Pope and 4 more8 hr
Sep 22, 5:08 PM CDTMesoscale DiscussionSPCAlexander, Bond, Brown, Calhoun, Cass, Christian and 44 more2 hr
Sep 22, 3:34 PM CDTMesoscale DiscussionSPCBartholomew, Boone, Brown, Clark, Clinton, Crawford and 35 more116 min

Nearby

Mesoscale Discussions in Illinois, 2006Mesoscale Discussions in Indiana, 2006Every mesoscale discussion in 2006

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.