Alert archive / Illinois / Tornado Warnings in 1998

Tornado Warning 127, NWS Lincoln, IL

August 4, 1998Macon County, Illinois

NWS Lincoln, IL issued this tornado warning at Aug 4, 1998, 7:59 PM CDT for Macon County, Illinois. It was in force for 61 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
Aug 4, 1998, 7:59 PM CDT (00:59 UTC)
Expired
Aug 4, 1998, 9:00 PM CDT
In force
61 min
Issued by
NWS Lincoln, IL
Area
Whole counties

County Macon County, IL

The radar

The Lincoln radar (KILX), 45 km from the middle of the area, began a volume at 00:59 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

Lincoln, IL (KILX), launched 00:00Z, 1.0 hours before the alert went out and 45 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 00:00Z on 1998-08-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 421 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 00:00Z on 1998-08-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 44 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
421 J/kg
Mixed-layer CIN
-53 J/kg
Mixed-layer LCL
1463 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
44 m²/s²
0-3 km storm-relative helicity
67 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.5

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KSPI 050101 RRA
TORSPI
ILC115-050200-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE LINCOLN IL
759 PM CDT TUE AUG 4 1998

THE NATIONAL WEATHER SERVICE IN LINCOLN HAS ISSUED A

* TORNADO WARNING FOR...
  MACON COUNTY IN CENTRAL ILLINOIS

* UNTIL 900 PM CDT

* AT 755 PM CDT... LINCOLN DOPPLER RADAR INDICATED A TORNADO 7 MILES
  WEST OF DECATUR...MOVING EAST AT 20 MPH.

* THIS STORM IS EXPECTED TO AFFECT AREAS AROUND...
  DECATUR
  NI4ANTIC
  HARRISTOWN
  MT ZION

TORNADOES ARE ESPECIALLY DANGEROUS AT NIGHT BECAUSE THEY ARE HARD
TO SEE. TAKE COVER IN A BASEMENT OR INTERIOR ROOM ON THE LOWEST
FLOOR.

JA/BK/EG

The office that day

Everything else NWS Lincoln, IL issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 4, 9:20 PM CDTFlash Flood WarningILXClark3 hr

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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.