Alert archive / Iowa / Severe Thunderstorm Watches in 1997

Severe Thunderstorm Watch 145

April 5, 199714 counties in Illinois; 42 counties in Iowa

The Storm Prediction Center issued this severe thunderstorm watch at Apr 5, 1997, 2:30 PM CST for 14 counties in Illinois; 42 counties in Iowa. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Apr 5, 1997, 2:30 PM CST (20:30 UTC)
Expired
Apr 5, 1997, 7:00 PM CST
In force
5 hr
Issued by
the Storm Prediction Center
All 56 counties

Benton County, IA, Black Hawk County, IA, Bremer County, IA, Buchanan County, IA, Butler County, IA, Cedar County, IA, Cerro Gordo County, IA, Chickasaw County, IA, Clayton County, IA, Clinton County, IA, Delaware County, IA, Des Moines County, IA, Dubuque County, IA, Emmet County, IA, Fayette County, IA, Floyd County, IA, Franklin County, IA, Grundy County, IA, Hancock County, IA, Hardin County, IA, Henry County, IA, Howard County, IA, Humboldt County, IA, Iowa County, IA, Jackson County, IA, Johnson County, IA, Jones County, IA, Kossuth County, IA, Linn County, IA, Louisa County, IA, Marshall County, IA, Mitchell County, IA, Muscatine County, IA, Palo Alto County, IA, Poweshiek County, IA, Scott County, IA, Tama County, IA, Washington County, IA, Winnebago County, IA, Winneshiek County, IA, Worth County, IA, Wright County, IA, Bureau County, IL, Carroll County, IL, Henry County, IL, Jo Daviess County, IL, Knox County, IL, LaSalle County, IL, Lee County, IL, Livingston County, IL, Marshall County, IL, Mercer County, IL, Putnam County, IL, Rock Island County, IL, Stark County, IL, Whiteside County, IL

The radar

The Quad Cities radar (KDVN), 128 km from the middle of the area, began a volume at 20:29 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.

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Apr 5, 2:30 PM CSTSevere Thunderstorm WarningILXFulton, Knox30 min
Apr 5, 2:40 PM CSTSevere Thunderstorm WarningDVNBenton, Johnson, Linn45 min
Apr 5, 2:56 PM CSTSevere Thunderstorm WarningDVNRock Island44 min
Apr 5, 2:56 PM CSTSevere Thunderstorm WarningDVNCedar44 min
Apr 5, 3:00 PM CSTSevere Thunderstorm WarningILXStark45 min
Apr 5, 3:04 PM CSTSevere Thunderstorm WarningDMXBlack Hawk16 min
Apr 5, 3:13 PM CSTSevere Thunderstorm WarningARXChickasaw, Floyd32 min
Apr 5, 3:13 PM CSTSevere Thunderstorm WarningARXFayette32 min
Apr 5, 3:17 PM CSTSevere Thunderstorm WarningDVNDelaware, Jones43 min
Apr 5, 3:17 PM CSTSevere Thunderstorm WarningDVNBuchanan43 min
Apr 5, 3:20 PM CSTSevere Thunderstorm WarningDMXBremer15 min
Apr 5, 3:28 PM CSTSevere Thunderstorm WarningDVNHenry, Whiteside47 min
Apr 5, 3:28 PM CSTSevere Thunderstorm WarningDVNClinton47 min
Apr 5, 3:36 PM CSTSevere Thunderstorm WarningILXMarshall39 min
Apr 5, 3:45 PM CSTSevere Thunderstorm WarningLOTLaSalle, Lee, Livingston45 min
Apr 5, 3:48 PM CSTSevere Thunderstorm WarningDVNCarroll, Jo Daviess42 min
Apr 5, 3:53 PM CSTSevere Thunderstorm WarningDVNBureau, Putnam47 min
Apr 5, 4:03 PM CSTSevere Thunderstorm WarningARXWinneshiek32 min
Apr 5, 4:26 PM CSTSevere Thunderstorm WarningLOTDeKalb, Grundy, Kendall, LaSalle34 min
Apr 5, 4:26 PM CSTSevere Thunderstorm WarningLOTFord, Livingston34 min
Apr 5, 4:26 PM CSTSevere Thunderstorm WarningLOTLee34 min

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 8.5 hours before the alert went out and 132 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 1997-04-05Temperature 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 1997-04-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 94 square meters per square second.1939587897Sfc1 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
515 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
94 m²/s²
0-3 km storm-relative helicity
99 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 5, 2:30 PM CSTSevere Thunderstorm WatchSPCBond, Cass, Champaign, Christian, Clark, Clay and 34 more5 hr
Apr 5, 4:15 PM CSTSevere Thunderstorm WatchSPCBoone, Bureau, Carroll, DeKalb, DuPage, Grundy and 13 more4 hr

Nearby

Severe Thunderstorm Watches in Iowa, 1997Severe Thunderstorm Watches in Illinois, 1997Every severe thunderstorm watch in 1997

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.