Alert archive / Illinois / Flash Flood Warnings in 1997

Flash Flood Warning 15, NWS Chicago, IL

June 15, 1997Boone County, McHenry County, Illinois

NWS Chicago, IL issued this flash flood warning at Jun 15, 1997, 11:56 PM CDT for Boone County, McHenry County, Illinois. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Jun 15, 1997, 11:56 PM CDT (04:56 UTC)
Expired
Jun 16, 1997, 3:00 AM CDT
In force
3 hr
Issued by
NWS Chicago, IL
Area
Whole counties

Counties Boone County, IL, McHenry County, IL

The radar

The Milwaukee radar (KMKX), 72 km from the middle of the area, began a volume at 04:58 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

Davenport, (KDVN), launched 00:00Z, 4.9 hours before the alert went out and 173 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 1997-06-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 654 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, Davenport, at 00:00Z on 1997-06-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 34 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
654 J/kg
Mixed-layer CIN
-18 J/kg
Mixed-layer LCL
1426 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
34 m²/s²
0-3 km storm-relative helicity
145 m²/s²
Significant tornado parameter
0.1
Supercell composite
0.7

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 15, 9:50 PM CDTSevere Thunderstorm WarningLOTBoone, McHenry55 min
Jun 15, 9:50 PM CDTSevere Thunderstorm WarningLOTWinnebago55 min
Jun 15, 10:18 PM CDTSevere Thunderstorm WarningLOTLake27 min
Jun 15, 11:36 PM CDTFlash Flood WarningLOTWinnebago3 hr

Nearby

Flash Flood Warnings in Illinois, 1997Every flash flood warning in 1997

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.