Alert archive / Illinois / Severe Thunderstorm Watches in 2005

Severe Thunderstorm Watch 666

July 23, 20059 counties in Illinois; Jasper County, Lake County, Porter County, Indiana

The Storm Prediction Center issued this severe thunderstorm watch at Jul 23, 2005, 4:25 PM CDT for 9 counties in Illinois; Jasper County, Lake County, Porter County, Indiana. It was in force for 69 min.

The area

The outline as issued.

The facts

Issued
Jul 23, 2005, 4:25 PM CDT (21:25 UTC)
Expired
Jul 23, 2005, 5:34 PM CDT
In force
69 min
Issued by
the Storm Prediction Center

Counties Cook County, IL, DuPage County, IL, Grundy County, IL, Kane County, IL, Kankakee County, IL, Kendall County, IL, Lake County, IL, McHenry County, IL, Will County, IL, Jasper County, IN, Lake County, IN, Porter County, IN

The radar

The Chicago radar (KLOT), 33 km from the middle of the area, began a volume at 21:28 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.

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 9.4 hours before the alert went out and 213 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 2005-07-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 76 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 12:00Z on 2005-07-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 190 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
76 J/kg
Mixed-layer CIN
-350 J/kg
Mixed-layer LCL
1286 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
190 m²/s²
0-3 km storm-relative helicity
240 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.0

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 23, 3:10 PM CDTMesoscale DiscussionSPCBoone, DeKalb, DuPage, Kane, Lake, McHenry and 3 more95 min
Jul 23, 4:49 PM CDTMesoscale DiscussionSPCBoone, Cook, DeKalb, DuPage, Grundy, Kane and 6 more86 min

Nearby

Severe Thunderstorm Watches in Illinois, 2005Severe Thunderstorm Watches in Indiana, 2005Every severe thunderstorm watch in 2005

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.