Monthly outlook for Boulder Hill, IL: average high 58.5°, average low 41.2°. That is 0.8° above the climate normal for October. Precipitation is expected on 1 day (about 0.3 inches), against a normal of 5 days and 1.5 inches. The warmest day looks like 22 October (68.7°), the coolest 29 October (28.2°).
58.5°/41.2°
Average high / low
+0.8°
Above normal
1 / 5
Wet days / normal
0.3 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
19 October – 28 October
61.3°
58.2°
+1.7°
29 October – 7 November
53.7°
54.2°
-0.3°
8 November – 17 November
at normal
48.6°
—
October records over 66 years
87.6°3 October 2025All-time high
21.9°24 October 1981All-time low
Tue, 2068° / 43°0
68 °
Boulder Hill, Tuesday, 20 October
Clear. High 68°, low 43°.
Pressure30.39 inHg
Wind3.4 mph SE
Humidity52%
Visibility6.2 mi
Dew point45°
Wed, 2167° / 43°0
67 °
Boulder Hill, Wednesday, 21 October
Clear. High 67°, low 43°.
Pressure30.27 inHg
Wind2.6 mph SW
Humidity55%
Visibility6.2 mi
Dew point48°
Thu, 2269° / 49°0
69 °
Boulder Hill, Thursday, 22 October
Clear. High 69°, low 49°.
Pressure30.33 inHg
Wind3.4 mph NE
Humidity63%
Visibility6.2 mi
Dew point54°
Fri, 2361° / 45°0
61 °
Boulder Hill, Friday, 23 October
Partly cloudy. High 61°, low 45°.
Pressure30.39 inHg
Wind6.2 mph SE
Humidity70%
Visibility6.2 mi
Dew point47°
Sat, 2461° / 44°0
61 °
Boulder Hill, Saturday, 24 October
Overcast. High 61°, low 44°.
Pressure30.45 inHg
Wind7.3 mph SE
Humidity57%
Visibility—
Dew point42°
Sun, 2567° / 47°0
67 °
Boulder Hill, Sunday, 25 October
Overcast. High 67°, low 47°.
Pressure30.30 inHg
Wind10.4 mph W
Humidity57%
Visibility—
Dew point47°
Mon, 2659° / 47°0.01
59 °
Boulder Hill, Monday, 26 October
Light rain. High 59°, low 47°.
Pressure30.33 inHg
Wind10.5 mph N
Humidity38%
Visibility—
Dew point31°
Tue, 2752° / 39°0
52 °
Boulder Hill, Tuesday, 27 October
Overcast. High 52°, low 39°.
Pressure30.33 inHg
Wind13.9 mph N
Humidity43%
Visibility—
Dew point29°
Wed, 2842° / 28°0
42 °
Boulder Hill, Wednesday, 28 October
Clear. High 42°, low 28°.
Pressure30.47 inHg
Wind13.4 mph N
Humidity39%
Visibility—
Dew point17°
Thu, 2948° / 28°0
48 °
Boulder Hill, Thursday, 29 October
Clear. High 48°, low 28°.
Pressure30.42 inHg
Wind8.5 mph W
Humidity30%
Visibility—
Dew point14°
Fri, 3053° / 32°0
53 °
Boulder Hill, Friday, 30 October
Overcast. High 53°, low 32°.
Pressure30.24 inHg
Wind16.4 mph SW
Humidity35%
Visibility—
Dew point22°
Sat, 3160° / 40°0
60 °
Boulder Hill, Saturday, 31 October
Overcast. High 60°, low 40°.
Pressure30.06 inHg
Wind17.8 mph SW
Humidity42%
Visibility—
Dew point33°
Sun, 0159° / 47°0
59 °
Boulder Hill, Sunday, 1 November
Overcast. High 59°, low 47°.
Pressure30.09 inHg
Wind10 mph NE
Humidity55%
Visibility—
Dew point40°
Mon, 0250° / 44°0.32
50 °
Boulder Hill, Monday, 2 November
Rain. High 50°, low 44°.
Pressure30.21 inHg
Wind13.9 mph N
Humidity90%
Visibility—
Dew point42°
Tue, 0353° / 43°0
53 °
Boulder Hill, Tuesday, 3 November
Light rain. High 53°, low 43°.
Pressure30.12 inHg
Wind8.8 mph N
Humidity73%
Visibility—
Dew point42°
From day 17 onward the outlook is built from 60-year climate statistics
Wed, 0453° / 40°0.09
53 °
Boulder Hill, Wednesday, 4 November
Climate normal for this date — 60-year average.
Average high53°
Average low40°
Average precipitation0.09 in
Chance of precipitation23%
Record high71° (2015)
Record low16° (1991)
Thu, 0553° / 39°0.11
53 °
Boulder Hill, Thursday, 5 November
Climate normal for this date — 60-year average.
Average high53°
Average low39°
Average precipitation0.11 in
Chance of precipitation28%
Record high75° (1978)
Record low18° (1991)
Fri, 0653° / 37°0.07
53 °
Boulder Hill, Friday, 6 November
Climate normal for this date — 60-year average.
Average high53°
Average low37°
Average precipitation0.07 in
Chance of precipitation27%
Record high72° (1975)
Record low23° (1991)
Sat, 0752° / 37°0.05
52 °
Boulder Hill, Saturday, 7 November
Climate normal for this date — 60-year average.
Average high52°
Average low37°
Average precipitation0.05 in
Chance of precipitation20%
Record high69° (2020)
Record low16° (1991)
Sun, 0851° / 37°0.06
51 °
Boulder Hill, Sunday, 8 November
Climate normal for this date — 60-year average.
Average high51°
Average low37°
Average precipitation0.06 in
Chance of precipitation20%
Record high74° (2020)
Record low12° (1991)
Mon, 0952° / 38°0.11
52 °
Boulder Hill, Monday, 9 November
Climate normal for this date — 60-year average.
Average high52°
Average low38°
Average precipitation0.11 in
Chance of precipitation33%
Record high73° (1999)
Record low16° (1991)
Tue, 1050° / 37°0.12
50 °
Boulder Hill, Tuesday, 10 November
Climate normal for this date — 60-year average.
Average high50°
Average low37°
Average precipitation0.12 in
Chance of precipitation38%
Record high72° (2020)
Record low17° (2017)
Wed, 1148° / 34°0.06
48 °
Boulder Hill, Wednesday, 11 November
Climate normal for this date — 60-year average.
Average high48°
Average low34°
Average precipitation0.06 in
Chance of precipitation27%
Record high71° (1964)
Record low16° (2019)
Thu, 1247° / 33°0.06
47 °
Boulder Hill, Thursday, 12 November
Climate normal for this date — 60-year average.
Average high47°
Average low33°
Average precipitation0.06 in
Chance of precipitation23%
Record high67° (1964)
Record low6° (2019)
Fri, 1347° / 33°0.05
47 °
Boulder Hill, Friday, 13 November
Climate normal for this date — 60-year average.
Average high47°
Average low33°
Average precipitation0.05 in
Chance of precipitation20%
Record high70° (1999)
Record low2° (2019)
Sat, 1448° / 33°0.07
48 °
Boulder Hill, Saturday, 14 November
Climate normal for this date — 60-year average.
Average high48°
Average low33°
Average precipitation0.07 in
Chance of precipitation32%
Record high70° (1971)
Record low13° (1986)
Sun, 1547° / 34°0.09
47 °
Boulder Hill, Sunday, 15 November
Climate normal for this date — 60-year average.
Average high47°
Average low34°
Average precipitation0.09 in
Chance of precipitation27%
Record high69° (2025)
Record low18° (1982)
Mon, 1647° / 33°0.05
47 °
Boulder Hill, Monday, 16 November
Climate normal for this date — 60-year average.
Average high47°
Average low33°
Average precipitation0.05 in
Chance of precipitation15%
Record high64° (1971)
Record low20° (1997)
Tue, 1748° / 34°0.1
48 °
Boulder Hill, Tuesday, 17 November
Climate normal for this date — 60-year average.
Average high48°
Average low34°
Average precipitation0.1 in
Chance of precipitation27%
Record high71° (2016)
Record low15° (2014)
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 Boulder Hill, IL 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 Boulder Hill, IL 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.