Alert archive / Illinois / Severe Thunderstorm Warnings in 2008

Severe Thunderstorm Warning 29, NWS Chicago, IL

May 26, 2008DeKalb County, LaSalle County, Lee County, Illinois

NWS Chicago, IL issued this severe thunderstorm warning at May 26, 2008, 1:16 AM CDT for DeKalb County, LaSalle County, Lee County, Illinois. It was in force for 59 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
May 26, 2008, 1:16 AM CDT (06:16 UTC)
Expired
May 26, 2008, 2:15 AM CDT
In force
59 min
Issued by
NWS Chicago, IL
Area
Storm-based polygon

Counties DeKalb County, IL, LaSalle County, IL, Lee County, IL

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
May 25, 7:54 PM CDTTornado WatchSPC6 hr

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 6.3 hours before the alert went out and 126 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 00:00Z on 2008-05-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1867 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, Davenport, at 00:00Z on 2008-05-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 148 square meters per square second.19395878Sfc1 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
1867 J/kg
Mixed-layer CIN
-68 J/kg
Mixed-layer LCL
1008 m above ground
0-6 km bulk shear
47 kt
0-1 km storm-relative helicity
148 m²/s²
0-3 km storm-relative helicity
204 m²/s²
Significant tornado parameter
1.2
Supercell composite
6.1

Open this sounding in Storm Lab

The office that day

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

IssuedProductOfficeCountiesLasted
May 25, 11:02 PM CDTAreal Flood AdvisoryLOTOgle, Winnebago14 days
May 25, 11:40 PM CDTAreal Flood AdvisoryLOTBoone, Lake, McHenry, Winnebago14 days
May 25, 11:42 PM CDTSpecial Marine WarningLOT77 min
May 26, 1:01 AM CDTAreal Flood AdvisoryLOTBoone, DeKalb, Lake, Lee, McHenry14 days
May 26, 1:37 AM CDTSevere Thunderstorm WarningLOTDuPage, Kane, Kendall, Will38 min
May 26, 2:01 AM CDTAreal Flood AdvisoryLOTCook, DeKalb, DuPage, Kane, Kendall, LaSalle and 2 more18 days

Nearby

Severe Thunderstorm Warnings in Illinois, 2008Every severe thunderstorm 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.