Alert archive / Iowa / Severe Thunderstorm Watches in 2002

Severe Thunderstorm Watch 476

June 26, 20025 counties in Illinois; 30 counties in Iowa; Clark County, Scotland County, Missouri

The Storm Prediction Center issued this severe thunderstorm watch at Jun 26, 2002, 4:30 PM CDT for 5 counties in Illinois; 30 counties in Iowa; Clark County, Scotland County, Missouri. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Jun 26, 2002, 4:30 PM CDT (21:30 UTC)
Expired
Jun 26, 2002, 9:00 PM CDT
In force
5 hr
Issued by
the Storm Prediction Center
All 37 counties

Benton County, IA, Buchanan County, IA, Cedar County, IA, Clayton County, IA, Clinton County, IA, Davis County, IA, Delaware County, IA, Des Moines County, IA, Dubuque County, IA, Henry County, IA, Iowa County, IA, Jackson County, IA, Jasper County, IA, Jefferson County, IA, Johnson County, IA, Jones County, IA, Keokuk County, IA, Lee County, IA, Linn County, IA, Louisa County, IA, Mahaska County, IA, Marion County, IA, Monroe County, IA, Muscatine County, IA, Poweshiek County, IA, Scott County, IA, Tama County, IA, Van Buren County, IA, Wapello County, IA, Washington County, IA, Henderson County, IL, Henry County, IL, Mercer County, IL, Rock Island County, IL, Whiteside County, IL, Clark County, MO, Scotland County, MO

The radar

The Quad Cities radar (KDVN), 112 km from the middle of the area, began a volume at 21:30 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.

Warnings issued inside it

8 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Jun 26, 4:35 PM CDTSevere Thunderstorm WarningDMXPoweshiek, Tama55 min
Jun 26, 5:14 PM CDTSevere Thunderstorm WarningDMXJasper61 min
Jun 26, 5:29 PM CDTSevere Thunderstorm WarningDVNIowa61 min
Jun 26, 5:37 PM CDTSevere Thunderstorm WarningDVNDubuque, Jackson53 min
Jun 26, 5:51 PM CDTSevere Thunderstorm WarningDVNJohnson54 min
Jun 26, 6:50 PM CDTSevere Thunderstorm WarningDVNCedar, Johnson, Muscatine40 min
Jun 26, 7:22 PM CDTSevere Thunderstorm WarningDVNRock Island58 min
Jun 26, 7:31 PM CDTSevere Thunderstorm WarningDVNMercer49 min

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 9.5 hours before the alert went out and 321 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 2002-06-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 945 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, Lincoln, IL at 12:00Z on 2002-06-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -5 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
945 J/kg
Mixed-layer CIN
-78 J/kg
Mixed-layer LCL
1012 m above ground
0-6 km bulk shear
7 kt
0-1 km storm-relative helicity
-5 m²/s²
0-3 km storm-relative helicity
40 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 26, 4:15 PM CDTSevere Thunderstorm WatchSPCAdair, Andrew, Boone, Buchanan, Caldwell, Carroll and 25 more5 hr

Nearby

Severe Thunderstorm Watches in Iowa, 2002Severe Thunderstorm Watches in Illinois, 2002Severe Thunderstorm Watches in Missouri, 2002Every severe thunderstorm watch in 2002

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.