Alert archive / Illinois / Mesoscale Discussions in 2007
Mesoscale Discussion 404
The Storm Prediction Center issued this mesoscale discussion at Mar 31, 2007, 9:17 PM CDT for 4 states. It was in force for 58 min.
The area
The outline as issued.
The facts
- Issued
- Mar 31, 2007, 9:17 PM CDT (02:17 UTC)
- Expired
- Mar 31, 2007, 10:15 PM CDT
- In force
- 58 min
- Issued by
- the Storm Prediction Center
All 59 counties
Bond County, IL, Boone County, IL, Champaign County, IL, Christian County, IL, Clinton County, IL, Coles County, IL, Cook County, IL, Cumberland County, IL, DeKalb County, IL, DeWitt County, IL, Douglas County, IL, DuPage County, IL, Effingham County, IL, Fayette County, IL, Ford County, IL, Grundy County, IL, Iroquois County, IL, Kane County, IL, Kankakee County, IL, Kendall County, IL, Lake County, IL, LaSalle County, IL, Lee County, IL, Livingston County, IL, Logan County, IL, Macon County, IL, Macoupin County, IL, Madison County, IL, Marion County, IL, Marshall County, IL, McHenry County, IL, McLean County, IL, Montgomery County, IL, Moultrie County, IL, Ogle County, IL, Piatt County, IL, Putnam County, IL, Shelby County, IL, Vermilion County, IL, Will County, IL, Winnebago County, IL, Woodford County, IL, Benton County, IN, Jasper County, IN, Lake County, IN, Newton County, IN, Porter County, IN, Warren County, IN, Berrien County, MI, Dane County, WI, Dodge County, WI, Jefferson County, WI, Kenosha County, WI, Milwaukee County, WI, Racine County, WI, Rock County, WI, Walworth County, WI, Washington County, WI, Waukesha County, WI
The radar
The Lincoln radar (KILX), 63 km from the middle of the area, began a volume at 02:18 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, 2.3 hours before the alert went out and 58 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.
- Mixed-layer CAPE
- 389 J/kg
- Mixed-layer CIN
- -2 J/kg
- Mixed-layer LCL
- 844 m above ground
- 0-6 km bulk shear
- 41 kt
- 0-1 km storm-relative helicity
- 158 m²/s²
- 0-3 km storm-relative helicity
- 177 m²/s²
- Significant tornado parameter
- 0.2
- Supercell composite
- 1.6
The text
As transmitted, in the capitals the NWS used until 2016.
000 ACUS11 KWNS 010217 SWOMCD SPC MCD 010217 MIZ000-INZ000-ILZ000-WIZ000-MOZ000-010315- MESOSCALE DISCUSSION 0404 NWS STORM PREDICTION CENTER NORMAN OK 0917 PM CDT SAT MAR 31 2007 AREAS AFFECTED...SERN WI...IL...NWRN IND CONCERNING...TORNADO WATCH 102...103... VALID 010217Z - 010315Z THE SEVERE WEATHER THREAT FOR TORNADO WATCH 102...103...CONTINUES. WELL ORGANIZED SQUALL LINE WITH EMBEDDED DAMAGING SEVERE WIND GUSTS IS RACING NEWD AT ROUGHLY 40-50 KT ACROSS CNTRL IL. GIVEN THE CURRENT SPEED/MOVEMENT...IT APPEARS LEADING EDGE OF STRONGEST ACTIVITY WILL APPROACH SWRN GREATER CHICAGO METRO AREA BY 03Z. UNTIL NARROW WEDGE OF STEEPER LOW LEVEL LAPSE RATES/BUOYANCY ACROSS NERN IL/NWRN IND IS OVERTURNED...UPDRAFT INTENSITY WILL REMAIN WELL ORGANIZED AND POTENTIALLY SEVERE. UPSTREAM...SECONDARY SQUALL LINE IS EVOLVING ALONG WIND SHIFT ACROSS WCNTRL IL FROM SANGAMON COUNTY...SWWD TO ST. CLAIR COUNTY. THIS ACTIVITY MAY CONTINUE TO EVOLVE AND APPROACH SEVERE LEVELS...HOWEVER EARLIER CONVECTION HAS STABILIZED AIRMASS AHEAD OF THIS CONVECTION AND THUS SEVERE WIND THREAT SHOULD BE SOMEWHAT LESS. ..DARROW.. 04/01/2007 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...IWX...IND...LOT...ILX...MKX...LSX...DVN... 38699028 40538921 42028972 43478945 43478799 41878665 40388713 38688880 38378966
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 31, 7:10 PM CDT | Mesoscale Discussion | SPC | Alexander, Hardin, Johnson, Massac, Pope, Pulaski and 3 more | 65 min |
| Mar 31, 7:25 PM CDT | Mesoscale Discussion | SPC | Boone, Bureau, Carroll, Cass, Champaign, Christian and 37 more | 65 min |
| Mar 31, 8:33 PM CDT | Tornado Watch | SPC | Cook, DuPage, Iroquois, Kankakee, Lake, Vermilion and 1 more | 3 hr |
Nearby
Mesoscale Discussions in Illinois, 2007Mesoscale Discussions in Wisconsin, 2007Mesoscale Discussions in Indiana, 2007Every mesoscale discussion in 2007
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.