Alert archive / Illinois / Flash Flood Warnings in 2023

Flash Flood Warning 15, NWS Quad Cities, IA

September 27, 2023Bureau County, Illinois

NWS Quad Cities, IA issued this flash flood warning at Sep 27, 2023, 4:05 AM CDT for Bureau 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: Sep 27, 2023, 4:05 AM CDT (09:05 UTC)
Expired: Sep 27, 2023, 10:15 AM CDT
In force: 6 hr
Issued by: NWS Quad Cities, IA
Area: Storm-based polygon
Flood severity: None

County Bureau County, IL

The radar

The Quad Cities radar (KDVN), 91 km from the middle of the area, began a volume at 09:07 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, 9.1 hours before the alert went out and 84 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: 96 J/kg
Mixed-layer CIN: -86 J/kg
Mixed-layer LCL: 1505 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: 9 m²/s²
0-3 km storm-relative helicity: 12 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 Quad Cities, IA wrote its last area forecast discussion before this flash flood warning went out at Sep 27, 2:47 AM CDT, 1 hour 18 minutes earlier.

Area forecast discussion, Sep 27, 2:47 AM CDT, 1 hour 18 minutes before

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Hazardous weather outlook, Sep 27, 3:23 AM CDT, 42 minutes before

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In the hours before

Special weather statement, Sep 27, 3:03 AM CDT, 1 hour 2 minutes before

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Special weather statement, Sep 27, 3:07 AM CDT, 58 minutes before

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The office that day

Everything else NWS Quad Cities, IA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Sep 26, 9:04 PM CDT	Special Weather Statement	DVN	Jackson	41 min
Sep 27, 4:41 AM CDT	Dense Fog Advisory	DVN	Iowa, Jefferson, Johnson, Keokuk, Washington	5 hr
Sep 26, 7:37 PM CDT	Flash Flood Warning	DVN	Jo Daviess	6 hr
Sep 26, 8:26 PM CDT	Special Weather Statement	DVN	Jo Daviess	49 min
Sep 26, 9:29 PM CDT	Special Weather Statement	DVN	Jo Daviess	46 min
Sep 26, 10:15 PM CDT	Flash Flood Warning	DVN	Carroll, Jo Daviess	3 hr
Sep 27, 3:07 AM CDT	Special Weather Statement	DVN	Bureau	68 min

Nearby

Flash Flood Warnings in Illinois, 2023 Every flash flood warning in 2023

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.