Monthly outlook for Ontario, WI: average high 64°, average low 49.9°. That is 4.5° above the climate normal for October. Precipitation is expected on 3 days (about 1.8 inches), against a normal of 5 days and 1.4 inches. The warmest day looks like 12 October (83.3°), the coolest 26 October (34.6°).
64°/49.9°
Average high / low
+4.5°
Above normal
3 / 5
Wet days / normal
1.8 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
12 October – 21 October
64.5°
57°
+4.2°
22 October – 31 October
63.2°
53.3°
+5.5°
1 November – 10 November
at normal
47.9°
—
October records over 66 years
87.3°3 October 2025All-time high
21.6°30 October 1988All-time low
Climate normals and records are computed from the nearest reference point — Norwalk (8 mi).
Tue, 1373° / 58°0
73 °
Ontario, Tuesday, 13 October
Overcast. High 73°, low 58°.
Pressure29.85 inHg
Wind10.6 mph NW
Humidity65%
Visibility6.2 mi
Dew point53°
Wed, 1465° / 51°0
65 °
Ontario, Wednesday, 14 October
Overcast. High 65°, low 51°.
Pressure30.15 inHg
Wind7.3 mph N
Humidity57%
Visibility6.2 mi
Dew point47°
Thu, 1560° / 52°0.03
60 °
Ontario, Thursday, 15 October
Light rain. High 60°, low 52°.
Pressure30.15 inHg
Wind4.5 mph E
Humidity71%
Visibility6.2 mi
Dew point49°
Fri, 1655° / 46°0
55 °
Ontario, Friday, 16 October
Clear. High 55°, low 46°.
Pressure30.45 inHg
Wind16.2 mph N
Humidity49%
Visibility6.2 mi
Dew point32°
Sat, 1760° / 39°0
60 °
Ontario, Saturday, 17 October
Clear. High 60°, low 39°.
Pressure30.36 inHg
Wind13.1 mph SW
Humidity37%
Visibility—
Dew point30°
Sun, 1860° / 42°0
60 °
Ontario, Sunday, 18 October
Clear. High 60°, low 42°.
Pressure30.09 inHg
Wind19.8 mph SW
Humidity41%
Visibility—
Dew point33°
Mon, 1962° / 49°0
62 °
Ontario, Monday, 19 October
Overcast. High 62°, low 49°.
Pressure30.09 inHg
Wind11.6 mph SW
Humidity54%
Visibility—
Dew point43°
Tue, 2061° / 47°0
61 °
Ontario, Tuesday, 20 October
Partly cloudy. High 61°, low 47°.
Pressure30.21 inHg
Wind7.6 mph SE
Humidity67%
Visibility—
Dew point48°
Wed, 2166° / 53°0
66 °
Ontario, Wednesday, 21 October
Overcast. High 66°, low 53°.
Pressure30.27 inHg
Wind13.7 mph SE
Humidity68%
Visibility—
Dew point53°
Thu, 2267° / 58°0.61
67 °
Ontario, Thursday, 22 October
Rain. High 67°, low 58°.
Pressure30.21 inHg
Wind13.9 mph S
Humidity78%
Visibility—
Dew point59°
Fri, 2372° / 64°0.81
72 °
Ontario, Friday, 23 October
Heavy rain. High 72°, low 64°.
Pressure30.18 inHg
Wind7.5 mph SE
Humidity79%
Visibility—
Dew point64°
Sat, 2465° / 59°0.37
65 °
Ontario, Saturday, 24 October
Rain. High 65°, low 59°.
Pressure29.77 inHg
Wind18.3 mph S
Humidity94%
Visibility—
Dew point60°
Sun, 2558° / 42°0
58 °
Ontario, Sunday, 25 October
Overcast. High 58°, low 42°.
Pressure29.94 inHg
Wind18.3 mph W
Humidity81%
Visibility—
Dew point43°
Mon, 2658° / 35°0
58 °
Ontario, Monday, 26 October
Overcast. High 58°, low 35°.
Pressure30.12 inHg
Wind13.4 mph W
Humidity46%
Visibility—
Dew point32°
Tue, 2758° / 40°0
58 °
Ontario, Tuesday, 27 October
Overcast. High 58°, low 40°.
Pressure29.88 inHg
Wind19.9 mph NW
Humidity49%
Visibility—
Dew point38°
From day 17 onward the outlook is built from 60-year climate statistics
Wed, 2852° / 39°0.08
52 °
Ontario, Wednesday, 28 October
Climate normal for this date — 60-year average.
Average high52°
Average low39°
Average precipitation0.08 in
Chance of precipitation25%
Record high67° (2016)
Record low26° (1969)
Thu, 2953° / 39°0.07
53 °
Ontario, Thursday, 29 October
Climate normal for this date — 60-year average.
Average high53°
Average low39°
Average precipitation0.07 in
Chance of precipitation27%
Record high78° (2024)
Record low24° (2019)
Fri, 3053° / 40°0.09
53 °
Ontario, Friday, 30 October
Climate normal for this date — 60-year average.
Average high53°
Average low40°
Average precipitation0.09 in
Chance of precipitation35%
Record high76° (2024)
Record low22° (1988)
Sat, 3151° / 39°0.1
51 °
Ontario, Saturday, 31 October
Climate normal for this date — 60-year average.
Average high51°
Average low39°
Average precipitation0.1 in
Chance of precipitation38%
Record high67° (2000)
Record low25° (1996)
Sun, 0150° / 38°0.15
50 °
Ontario, Sunday, 1 November
Climate normal for this date — 60-year average.
Average high50°
Average low38°
Average precipitation0.15 in
Chance of precipitation27%
Record high72° (2000)
Record low22° (2023)
Mon, 0249° / 37°0.07
49 °
Ontario, Monday, 2 November
Climate normal for this date — 60-year average.
Average high49°
Average low37°
Average precipitation0.07 in
Chance of precipitation30%
Record high69° (2022)
Record low15° (1991)
Tue, 0349° / 36°0.06
49 °
Ontario, Tuesday, 3 November
Climate normal for this date — 60-year average.
Average high49°
Average low36°
Average precipitation0.06 in
Chance of precipitation25%
Record high70° (2008)
Record low12° (1991)
Wed, 0448° / 36°0.09
48 °
Ontario, Wednesday, 4 November
Climate normal for this date — 60-year average.
Average high48°
Average low36°
Average precipitation0.09 in
Chance of precipitation27%
Record high71° (2008)
Record low4° (1991)
Thu, 0548° / 36°0.09
48 °
Ontario, Thursday, 5 November
Climate normal for this date — 60-year average.
Average high48°
Average low36°
Average precipitation0.09 in
Chance of precipitation33%
Record high67° (2016)
Record low15° (1991)
Fri, 0648° / 35°0.06
48 °
Ontario, Friday, 6 November
Climate normal for this date — 60-year average.
Average high48°
Average low35°
Average precipitation0.06 in
Chance of precipitation28%
Record high68° (2020)
Record low6° (1991)
Sat, 0747° / 34°0.02
47 °
Ontario, Saturday, 7 November
Climate normal for this date — 60-year average.
Average high47°
Average low34°
Average precipitation0.02 in
Chance of precipitation15%
Record high67° (2020)
Record low-9° (1991)
Sun, 0847° / 34°0.03
47 °
Ontario, Sunday, 8 November
Climate normal for this date — 60-year average.
Average high47°
Average low34°
Average precipitation0.03 in
Chance of precipitation25%
Record high69° (1999)
Record low-4° (1991)
Mon, 0947° / 34°0.09
47 °
Ontario, Monday, 9 November
Climate normal for this date — 60-year average.
Average high47°
Average low34°
Average precipitation0.09 in
Chance of precipitation37%
Record high70° (1999)
Record low16° (2017)
Tue, 1045° / 33°0.12
45 °
Ontario, Tuesday, 10 November
Climate normal for this date — 60-year average.
Average high45°
Average low33°
Average precipitation0.12 in
Chance of precipitation33%
Record high67° (2022)
Record low11° (2017)
About the monthly outlook
How accurate is a 30-day forecast?
The first 16 days come from weather models — reliable for the first 3–5 days and progressively less so after that. Days 17 through 30 for Ontario, WI are built from the climate normal, the 60-year average, so they show typical weather for those dates rather than a specific forecast.
What does "above normal" mean?
We compare the forecast against the climate normal for those exact calendar days, computed from 60 years of observations. The deviation shows how much the coming month differs from a typical one.
Where do the 66-year records come from?
They are real temperature extremes recorded in Ontario, WI since 1960: the highest and lowest reading for each calendar date, with the year it happened.
How often is it updated?
The forecast portion refreshes every hour; the climate portion is based on long-term data and stays stable.