Ottawa, IL 61350 Monthly Weather

LaSalle County3:44 PM CDT41.35°N, 88.84°W
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October 2026

Sun
Mon
Tue
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Sat
164°/59°0.81 inAvg 71°/48°
269°/49°1.32 inAvg 71°/48°
367°/43°Avg 70°/47°
472°/44°Avg 70°/47°
574°/46°Avg 69°/46°
671°/46°Avg 69°/46°
774°/47°Avg 68°/46°
880°/51°Avg 68°/45°
976°/50°Avg 67°/45°
1065°/51°0.06 inAvg 67°/45°
1182°/49°Avg 66°/44°
1280°/50°Avg 66°/44°
1386°/62°Avg 66°/44°
1478°/62°0.05 inAvg 65°/43°
1565°/57°0.02 inAvg 65°/43°
1665°/45°0.80 inAvg 64°/42°
1755°/33°<0.01 inAvg 64°/42°
1856°/33°Avg 63°/42°
1963°/37°Avg 63°/42°
2069°/38°Avg 62°/41°
21 Sunny 74°/46°Avg 62°/41°
22 Sunny 75°/47°Avg 61°/40°
23 Sunny 74°/49°Avg 61°/40°
24 Mostly Sunny 74°/52°Avg 60°/40°
25 Partly Sunny 75°/51°Avg 60°/40°
26 Partly Sunny 70°/48°Avg 59°/39°
27 Slight Chance Rain Showers 60°/42°Avg 59°/39°
28 Partly cloudy 66°/49°Avg 58°/38°
29 Heavy rain 65°/40°Avg 58°/38°
30 Sunny 58°/36°Avg 57°/38°
31Avg 56°/37°
Average high71° (normal 67°)
Average low48° (normal 45°)
Warmest / coldest86° / 33°
Precipitation3.07 in (normal 1.93 in to date)
Record high today87° (1979)
Record low today21° (1925)

Observed: Ottawa 4sw, 6 km away, records since 1890. Normals 1991–2020. Climate data from NOAA's Regional Climate Centers (ACIS); recent days are preliminary. Days ahead: the forecast.

Forecasts, observations and alerts in the United States come from the National Weather Service (NOAA); radar from NOAA's Multi-Radar Multi-Sensor system; satellite imagery from NASA's Global Imagery Browse Services (GIBS) and NOAA's GOES satellites; the map from the U.S. Geological Survey's National Map; air quality from AirNow (EPA and its partners); hurricane information from the National Hurricane Center; climate normals and records from NOAA's Regional Climate Centers (ACIS). Forecasts outside the United States and the UV index: MET Norway (CC BY 4.0); observations outside the U.S.: airport reports via NOAA's Aviation Weather Center. Place names: GeoNames (CC BY 4.0). Data are copied on a schedule and may lag the sources; for warnings that affect your safety, follow your local National Weather Service office and emergency officials. Weather news is drawn from the 4Conservative index and reflects what the press published. Terms of use.