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Flood Warning issued September 27 at 8:09PM CDT until September 28 at 7:00PM CDT by NWS Chicago IL

7.0
42.4629°N, 87.9314°W·US-IL
Started 2h ago
NWS flood alerts data as of
Event Details
Typeflood
Severity7.0
Statusactive
Location42.4629°N, 87.9314°W (IL)
Started2026-09-28T01:09:00+00:00
Last Updated2026-09-28T03:30:15.663+00:00
Sourcenoaa_ahps
Source URLapi.weather.gov
Confidence1.00
Impact Zones
Modeled Inundation
Where the National Water Model's latest analysis puts water inside the warning area. Experimental; the warning polygon is the official boundary.
NWS polygon
Severe Impact Zone
Active flood warning area. Significant property damage possible.
NWS polygon

Zone estimates are based on scientific models and may differ from actual local conditions.

Impact Analysis

This event's zone is the NWS warning polygon. Population and structure estimates are not computed inside NWS polygons yet, so none are shown.

Historical Comparison
2023 COOK County, ILLINOIS Flash Flood76% match

Flash Flood in ILLINOIS, 48km from current event, $500M in recorded damage

COOK County, ILLINOISDamage: $500.0M
2009 KENOSHA County, WISCONSIN Flash Flood74% match

Flash Flood in WISCONSIN, 18km from current event, $12M in recorded damage

KENOSHA County, WISCONSINDamage: $12.3M
2025 MILWAUKEE County, WISCONSIN Flash Flood74% match

Flash Flood in WISCONSIN, 43km from current event, $60M in recorded damage

MILWAUKEE County, WISCONSINDamage: $60.0MFatalities: 1

Historical comparison based on peril type, geography, and severity. Past events do not predict future outcomes.

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Related
Lake County, IL disaster historyAll US hazard profilesScoring methodology

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Zone estimates are based on scientific models and may differ from actual local conditions.