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: Calumet Harbor IL to Gary IN (LMZ743) Issued by: National Weather Service Chicago, IL Last Update: 244 PM CDT Thu Sep 18 2025 |  |
| Tonight: Northeast winds 5 to 10 kt becoming east late. Mostly clear. Waves 1 to 2 ft. Friday: Southeast winds 5 to 10 kt becoming northeast 10 to 15 kt in the afternoon. Mostly sunny in the morning, then becoming partly cloudy. Waves 1 to 2 ft. Friday Night: East winds 10 to 15 kt becoming southeast overnight. Slight chance of showers late in the evening, then chance of showers overnight. Waves 1 to 2 ft. Saturday: Southeast winds 10 to 15 kt becoming east in the afternoon. Slight chance of showers in the morning, then chance of showers and slight chance of thunderstorms in the afternoon. Waves 1 to 2 ft. | |
| Zone Forecast: Calumet Harbor IL to Gary IN (LMZ743) | |
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