Alert archive / Illinois / Tornado Warnings in 2001

Tornado Warning 7, NWS Chicago, IL

August 25, 2001DuPage County, Illinois

NWS Chicago, IL issued this tornado warning at Aug 25, 2001, 3:15 PM CDT for DuPage County, Illinois. It was in force for 30 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 25, 2001, 3:15 PM CDT (20:15 UTC)
Expired
Aug 25, 2001, 3:45 PM CDT
In force
30 min
Issued by
NWS Chicago, IL
Area
Whole counties

County DuPage County, IL

The radar

The Chicago radar (KLOT), 28 km from the middle of the area, began a volume at 20:16 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 12:00Z, 8.3 hours before the alert went out and 194 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 12:00Z on 2001-08-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1008 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 12:00Z on 2001-08-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 149 square meters per square second.1939Sfc1 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
1008 J/kg
Mixed-layer CIN
-128 J/kg
Mixed-layer LCL
1154 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
149 m²/s²
0-3 km storm-relative helicity
160 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.

670 
WFUS53 KLOT 252015
TORCHI
ILC043-252045-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE CHICAGO IL
315 PM CDT SAT AUG 25 2001

THE NATIONAL WEATHER SERVICE IN CHICAGO HAS ISSUED A

* TORNADO WARNING FOR...
  SOUTHERN DUPAGE COUNTY IN NORTHEAST ILLINOIS

* UNTIL 345 PM CDT

* AT 315 PM CDT...TRAINED WEATHER SPOTTERS REPORTED A TORNADO 3 MILES
  SOUTHWEST OF LISLE...OR ABOUT OVER NAPERVILLE...MOVING NORTHEAST AT
  10 MPH.

* THE TORNADO WILL BE NEAR
  WHEATON AROUND 330 PM CDT
  DOWNERS GROVE AROUND 340 PM CDT
  YORK CENTER AROUND 345 PM CDT

GO TO THE BASEMENT AND SEEK SHELTER UNDER THE STAIRS OR UNDER A HEAVY
PIECE OF FURNITURE

REPORT SEVERE WEATHER TO THE NEAREST LAW ENFORCEMENT AGENCY. THEY
WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE.

NNNN

Nearby

Tornado Warnings in Illinois, 2001Every tornado warning in 2001Tornadoes in 2001

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.