7-Day Forecast 41.35°N 88.85°W (Text-Only)
NWS Forecast for: Ottawa IL
Issued by: National Weather Service Chicago, IL
Last Update: 3:46 am CDT Aug 19, 2026




Today: A 20 percent chance of showers after 4pm. Patchy fog before 9am. Otherwise, mostly cloudy, with a high near 80. Calm wind becoming north around 5 mph in the afternoon.

Tonight: Mostly cloudy, then gradually becoming mostly clear, with a low around 62. Northeast wind around 5 mph.

Thursday: Sunny, with a high near 80. North wind around 5 mph becoming calm.

Thursday Night: Mostly clear, with a low around 62. Calm wind.

Friday: A 30 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 80. Light south wind becoming southwest 5 to 10 mph in the morning. Winds could gust as high as 15 mph.

Friday Night: A 20 percent chance of showers and thunderstorms before 1am. Partly cloudy, with a low around 65.

Saturday: A 20 percent chance of showers and thunderstorms. Sunny, with a high near 80.

Saturday Night: Mostly clear, with a low around 62.

Sunday: Mostly sunny, with a high near 77.

Sunday Night: Partly cloudy, with a low around 60.

Monday: Mostly sunny, with a high near 78.

Monday Night: Partly cloudy, with a low around 62.

Tuesday: Mostly sunny, with a high near 81.



Ottawa IL
 41.35°N 88.85°W

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