Alert archive / Illinois / Winter Storm Warnings in 2008

Winter Storm Warning 7, NWS Chicago, IL

December 17, 200812 counties in Illinois; Lake County, Porter County, Indiana

NWS Chicago, IL issued this winter storm warning at Dec 17, 2008, 3:29 PM CST for 12 counties in Illinois; Lake County, Porter County, Indiana. It took effect at Dec 18, 2008, 7:00 PM CST. It was in force for 16 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Dec 17, 2008, 3:29 PM CST (21:29 UTC)
In effect from
Dec 18, 2008, 7:00 PM CST
Expired
Dec 19, 2008, 10:56 AM CST
In force
16 hr
Issued by
NWS Chicago, IL

Counties Boone County, IL, DeKalb County, IL, DuPage County, IL, Grundy County, IL, Kane County, IL, Kendall County, IL, Lake County, IL, LaSalle County, IL, Lee County, IL, McHenry County, IL, Ogle County, IL, Winnebago County, IL, Lake County, IN, Porter County, IN

The radar

The Chicago radar (KLOT), 42 km from the middle of the area, began a volume at 21:29 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

Davenport, (KDVN), launched 12:00Z, 9.5 hours before the alert went out and 172 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, Davenport, at 12:00Z on 2008-12-17Temperature 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, Davenport, at 12:00Z on 2008-12-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -38 square meters per square second.1939587897117136156Sfc1 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
631 m above ground
0-6 km bulk shear
109 kt
0-1 km storm-relative helicity
-38 m²/s²
0-3 km storm-relative helicity
87 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The office that day

Everything else NWS Chicago, IL issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Dec 17, 3:25 AM CSTWinter Storm WatchLOTBoone, DeKalb, DuPage, Ford, Grundy, Iroquois and 10 more12 hr
Dec 17, 2:27 PM CSTGale WatchLOT13 hr
Dec 17, 3:29 PM CSTIce Storm WarningLOTFord, Iroquois, Kankakee, Livingston43 hr
Dec 17, 5:35 PM CSTAreal Flood WarningLOTLee, Ogle4 hr

Nearby

Winter Storm Warnings in Illinois, 2008Winter Storm Warnings in Indiana, 2008Every winter storm warning in 2008

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.