Alert archive / Illinois / Tornado Warnings in 1998

Tornado Warning 4, NWS Quad Cities, IA

April 7, 1998Hancock County, Illinois

NWS Quad Cities, IA issued this tornado warning at Apr 7, 1998, 4:35 PM CDT for Hancock County, Illinois. It was in force for 35 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Apr 7, 1998, 4:35 PM CDT (21:35 UTC)
Expired
Apr 7, 1998, 5:10 PM CDT
In force
35 min
Issued by
NWS Quad Cities, IA
Area
Whole counties

County Hancock County, IL

The radar

The Quad Cities radar (KDVN), 143 km from the middle of the area, began a volume at 21:38 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.

What was reported inside it

TimeReportWhereRemark
Apr 7, 4:45 PM CDTThunderstorm WindElvaston, IL

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The watch it was issued in

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

IssuedProductOfficeLasted
Apr 7, 2:00 PM CDTTornado WatchSPC6 hr

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 9.6 hours before the alert went out and 146 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 1998-04-07Temperature 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°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Davenport, at 12:00Z on 1998-04-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 101 square meters per square second.193958Sfc1 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
1589 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
101 m²/s²
0-3 km storm-relative helicity
31 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 072135 RRA
TORMLI
ILC067-072210-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
435 PM CDT TUE APR 7 1998

* TORNADO WARNING FOR
  HANCOCK COUNTY - WEST CENTRAL ILLINOIS

* UNTIL 510 PM CDT
 
* SOME LOCATIONS AFFECTED BY THIS TORNADO
  ELVASTON                                   AROUND 440 PM CDT
  BENTLEY                                    AROUND 440 PM CDT
  CARTHAGE                                   AROUND 450 PM CDT
  FERRIS                                     AROUND 455 PM CDT
  ADRIAN                                     AROUND 505 PM CDT

* AT 434 PM CDT...DOPPLER RADAR AND SPOTTER REPORTS INDICATED A
  TORNADO IN THE VICINITY OF KEOKUK MOVING NORTHEA8ST AT 25 MPH.

GO TO THE BASEMENT AND GET UNDER A WORKBENCH OR STURDY PIECE OF
FURNITURE. IF NO BASEMENT IS AVAILABLE...GO TO A SMALL INTERIOR
ROOM ON THE LOWEST FLOOR!

HENDRICKS

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 7, 4:25 PM CDTSevere Thunderstorm WarningDVNHancock50 min
Apr 7, 4:50 PM CDTTornado WarningDVNMcDonough50 min
Apr 7, 5:01 PM CDTSevere Thunderstorm WarningDVNWarren49 min
Apr 7, 5:31 PM CDTTornado WarningDVNWarren34 min
Apr 7, 6:05 PM CDTTornado WarningDVNWarren35 min
Apr 7, 6:06 PM CDTTornado WarningDVNMercer49 min

Nearby

Tornado Warnings in Illinois, 1998Every tornado warning in 1998Tornadoes in 1998

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.