Alert archive / Illinois / Tornado Warnings in 1998

Tornado Warning 8, NWS Quad Cities, IA

April 7, 1998Warren County, Illinois

NWS Quad Cities, IA issued this tornado warning at Apr 7, 1998, 6:05 PM CDT for Warren 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, 6:05 PM CDT (23:05 UTC)
Expired: Apr 7, 1998, 6:40 PM CDT
In force: 35 min
Issued by: NWS Quad Cities, IA
Area: Whole counties

County Warren County, IL

The radar

The Quad Cities radar (KDVN), 85 km from the middle of the area, began a volume at 23:05 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

Time	Report	Where	Remark
Apr 7, 6:13 PM CDT	Tornado F0	Gerlaw, 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.

Issued	Product	Office	Lasted
Apr 7, 2:00 PM CDT	Tornado Watch	SPC	6 hr

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 11.1 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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 072305 RRA
TORMLI
ILC187-072340-

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

* TORNADO WARNING FOR
  WARREN COUNTY - WEST CENTRAL ILLINOIS

* UNTIL 640 PM CDT
 
* SOME LOCATIONS AFFECTED BY THIS TORNADO
  UTAH                                       AROUND 605 PM CDT
  ALEXIS                                     AROUND 610 PM CDT
  SHANGHAI CITY                              AROUND 615 PM CDT

* AT 602 PM CDT...DOPPLER RADAR AND SPOTTER REPORTS INDICATED A
  TORNADO 10 MILES WEST OF GALESBURG OR 4 MILES WEST OF UTAH MOVING
  NORTHEAST AT 25 MPH.

IF YOU ARE IN A CAR...GO INTO A NEARBY STURDY BUILDING! AS A LAST
RESORT LIE FLAT IXN A DITCH AND COVER YOUR HEAD.

HENDRICKS

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 7, 4:25 PM CDT	Severe Thunderstorm Warning	DVN	Hancock	50 min
Apr 7, 4:35 PM CDT	Tornado Warning	DVN	Hancock	35 min
Apr 7, 4:50 PM CDT	Tornado Warning	DVN	McDonough	50 min
Apr 7, 5:01 PM CDT	Severe Thunderstorm Warning	DVN	Warren	49 min
Apr 7, 5:31 PM CDT	Tornado Warning	DVN	Warren	34 min
Apr 7, 6:06 PM CDT	Tornado Warning	DVN	Mercer	49 min

Nearby

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