Tropical Moisture Brings Slight Risk of Excessive Rainfall to the Southwest; Strong to Locally Severe Storms on the Plains
Heavy rain and flash flooding are possible across portions of the Southwest through Friday, where Flood Watches are in effect. Strong to locally severe thunderstorms are possible today across portions of the Plains. A tropical wave is causing heavy rainfall in Puerto Rico and the Virgin Islands, which may cause urban and small stream flooding and landslides today. Read More >
| NWS Forecast for: Northerly Island to Calumet Harbor IL (LMZ742) Issued by: National Weather Service Chicago, IL Last Update: 949 AM CDT Thu Sep 18 2025 | |
| Rest Of Today: Southeast winds 5 to 10 kt becoming northeast 10 to 15 kt in the afternoon. Mostly sunny. Waves around 1 ft. Tonight: Northeast winds 5 to 10 kt. Mostly clear. Waves 1 to 2 ft. Friday: East winds 10 to 15 kt. Mostly sunny in the morning, then becoming partly cloudy. Waves 1 to 3 ft. Friday Night: East winds 10 to 15 kt becoming southeast 15 to 20 kt overnight. Slight chance of showers and thunderstorms. Waves 2 to 4 ft building to 3 to 5 ft. | |
| Zone Forecast: Northerly Island to Calumet Harbor IL (LMZ742) | |
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