Alert archive / Illinois / Tornado Warnings in 1997

Tornado Warning 11, NWS Quad Cities, IA

April 30, 1997Jo Daviess County, Illinois

NWS Quad Cities, IA issued this tornado warning at Apr 30, 1997, 4:58 PM CDT for Jo Daviess County, Illinois. It was in force for 32 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
Apr 30, 1997, 4:58 PM CDT (21:58 UTC)
Expired
Apr 30, 1997, 5:30 PM CDT
In force
32 min
Issued by
NWS Quad Cities, IA
Area
Whole counties

County Jo Daviess County, IL

The radar

The Quad Cities radar (KDVN), 89 km from the middle of the area, began a volume at 21:59 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, 10.0 hours before the alert went out and 86 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 1997-04-30Temperature 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 1997-04-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 75 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1366 m above ground
0-6 km bulk shear
54 kt
0-1 km storm-relative helicity
75 m²/s²
0-3 km storm-relative helicity
180 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
TTAA00 KMLI 302200 RRA
TORMLI
ILC085-302230-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
458 PM CDT WED APR 30 1997

* TORNADO WARNING FOR
  JO DAVIESS COUNTY - NORTHWESTERN ILLINOIS

* UNTIL 530 PM CDT
 
* SOME LOCATIONS AFFECTED

  HANOVER
  ELIZABETH
  WOODBINE
  SCHAPVILLE

* AT 458 PM CDT RADAR INDICATED A TORNADO NEAR HANOVER...23 MILES
  SOUTHEAST OF DUBUQUE MOVING NORTHEAST AT 40 MILES AN HOUR.

* THE STORM PWILL BE OVER HANOVER BY 500 PM AND WOODBINE AT 512 PM
  CDT.

IF YOU ARE NEAR THIS DANGEROUS STORM, TAKE COVER IMMEDIATELY IN THE
LOWEST FLOOR AND INNERMOST ROOM OF A BUILDING.

HELGESON

The office that day

Everything else NWS Quad Cities, IA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 30, 1:36 PM CDTSevere Thunderstorm WarningDVNHancock34 min
Apr 30, 1:41 PM CDTTornado WarningDVNHancock34 min
Apr 30, 2:06 PM CDTTornado WarningDVNMcDonough34 min
Apr 30, 2:22 PM CDTTornado WarningDVNWarren48 min
Apr 30, 3:30 PM CDTTornado WarningDVNHenry50 min
Apr 30, 4:46 PM CDTTornado WarningDVNCarroll, Whiteside34 min

Nearby

Tornado Warnings in Illinois, 1997Every tornado warning in 1997Tornadoes 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.