Alert archive / Illinois / Flash Flood Warnings in 2008

Flash Flood Warning 34, NWS Chicago, IL

December 20, 2008Kane County, Illinois

NWS Chicago, IL issued this flash flood warning at Dec 20, 2008, 5:16 AM CST for Kane County, Illinois. It was in force for 6 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: Dec 20, 2008, 5:16 AM CST (11:16 UTC)
Expired: Dec 20, 2008, 11:35 AM CST
In force: 6 hr
Issued by: NWS Chicago, IL
Area: Storm-based polygon
Flood severity: None

County Kane County, IL

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 11.3 hours before the alert went out and 175 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: 720 m above ground
0-6 km bulk shear: 81 kt
0-1 km storm-relative helicity: -4 m²/s²
0-3 km storm-relative helicity: -2 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Chicago, IL wrote its last area forecast discussion before this flash flood warning went out at Dec 20, 4:21 AM CST, 55 minutes earlier.

Area forecast discussion, Dec 20, 4:21 AM CST, 55 minutes before

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Hazardous weather outlook, Dec 20, 5:02 AM CST, 14 minutes before

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</head>
<body>
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      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
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        The site you requested is temporarily down for maintenance or an unexpected outage.
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        Please try again in a few minutes.
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The office that day

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

Issued	Product	Office	Counties	Lasted
Dec 20, 3:16 AM CST	Gale Watch	LOT		13 hr
Dec 20, 3:16 AM CST	Gale Warning	LOT		54 hr
Dec 20, 3:16 AM CST	Heavy Freezing Spray Warning	LOT		54 hr
Dec 20, 4:17 AM CST	Wind Chill Advisory	LOT	Boone, DeKalb, DuPage, Ford, Grundy, Iroquois and 10 more	56 hr
Dec 20, 4:17 AM CST	Winter Storm Watch	LOT	Boone, Lake, McHenry, Ogle, Winnebago	7 hr
Dec 20, 10:06 AM CST	Small Craft Advisory	LOT		11 hr
Dec 20, 10:57 AM CST	Winter Weather Advisory	LOT	Boone, DeKalb, DuPage, Grundy, Kane, Kankakee and 7 more	37 hr

Nearby

Flash Flood Warnings in Illinois, 2008 Every flash flood warning in 2008

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.