Alert archive / Illinois / Tornado Warnings in 2000

Tornado Warning 21, NWS Chicago, IL

September 11, 2000Ogle County, Illinois

NWS Chicago, IL issued this tornado warning at Sep 11, 2000, 8:25 PM CDT for Ogle County, Illinois. It was in force for 10 min. 3 reports 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
Sep 11, 2000, 8:25 PM CDT (01:25 UTC)
Expired
Sep 11, 2000, 8:35 PM CDT
In force
10 min
Issued by
NWS Chicago, IL
Area
Whole counties

County Ogle County, IL

The radar

The Chicago radar (KLOT), 113 km from the middle of the area, began a volume at 01:27 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
Sep 11, 8:40 PM CDTHail 0.75Rochelle, IL
Sep 11, 8:45 PM CDTThunderstorm Wind 58 EOregon, IL
Sep 11, 8:45 PM CDTThunderstorm Wind 60 EByron, 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
Sep 11, 7:00 PM CDTSevere Thunderstorm WatchSPC4 hr

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 1.4 hours before the alert went out and 108 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 00:00Z on 2000-09-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1371 joules per kilogram.LCLLFCEL10008507005003002001001 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 00:00Z on 2000-09-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 57 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
1371 J/kg
Mixed-layer CIN
-112 J/kg
Mixed-layer LCL
2176 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
57 m²/s²
0-3 km storm-relative helicity
156 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 
WFUS53 KLOT 120126
TORCHI

ILC141-120135-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE CHICAGO IL
825 PM CDT MON SEP 11 2000

THE NATIONAL WEATHER SERVICE IN CHICAGO HAS ISSUED A

* TORNADO WARNING FOR...
  OGLE COUNTY IN NORTH CENTRAL ILLINOIS

* UNTIL 835 PM CDT

* AT 825 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM WITH STRONG ROTATION 2 MILES NORTHEAST OF LEAF
  RIVER...OR ABOUT 7U MILES NORTHEAST OF MOUNT MORRIS...MOVING EAST AT
  50 MPH. THIS STORM COULD PRODUCE A TORNADO AT ANY TIME.

$$
WILSON

NNNN

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 11, 8:07 PM CDTSevere Thunderstorm WarningLOTOgle, Winnebago38 min
Sep 11, 8:07 PM CDTSevere Thunderstorm WarningLOTLee38 min
Sep 11, 8:57 PM CDTSevere Thunderstorm WarningLOTBoone, DeKalb, Lee, Ogle48 min
Sep 11, 8:57 PM CDTSevere Thunderstorm WarningLOTKane, McHenry48 min
Sep 11, 9:28 PM CDTSevere Thunderstorm WarningLOTCook, DuPage, Lake47 min
Sep 11, 9:58 PM CDTSevere Thunderstorm WarningLOTGrundy, Kendall, LaSalle, Will62 min
Sep 11, 10:50 PM CDTSevere Thunderstorm WarningLOTFord, Iroquois, Kankakee, Livingston55 min
Sep 11, 11:44 PM CDTSevere Thunderstorm WarningLOTFord, Iroquois, Kankakee, Livingston61 min

Nearby

Tornado Warnings in Illinois, 2000Every tornado warning in 2000Tornadoes in 2000

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.