Monthly outlook for Boulder Hill, IL: average high 58.3°, average low 41.5°. That is 0.8° above the climate normal for October. Precipitation is expected on 3 days (about 0.4 inches), against a normal of 5 days and 1.5 inches. The warmest day looks like 21 October (70.4°), the coolest 28 October (27.1°).
58.3°/41.5°
Average high / low
+0.8°
Above normal
3 / 5
Wet days / normal
0.4 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
20 October – 29 October
59.6°
57.9°
+0.9°
30 October – 8 November
56.1°
53.8°
+1.3°
9 November – 18 November
at normal
48.2°
—
October records over 66 years
87.6°3 October 2025All-time high
21.9°24 October 1981All-time low
Wed, 2170° / 44°0
70 °
Boulder Hill, Wednesday, 21 October
Clear. High 70°, low 44°.
Pressure30.27 inHg
Wind2.7 mph SW
Humidity53%
Visibility6.2 mi
Dew point47°
Thu, 2269° / 50°0
69 °
Boulder Hill, Thursday, 22 October
Clear. High 69°, low 50°.
Pressure30.30 inHg
Wind4.5 mph NE
Humidity65%
Visibility6.2 mi
Dew point55°
Fri, 2362° / 45°0
62 °
Boulder Hill, Friday, 23 October
Mostly clear. High 62°, low 45°.
Pressure30.39 inHg
Wind5.3 mph SE
Humidity71%
Visibility6.2 mi
Dew point49°
Sat, 2463° / 44°0
63 °
Boulder Hill, Saturday, 24 October
Overcast. High 63°, low 44°.
Pressure30.39 inHg
Wind7.2 mph S
Humidity56%
Visibility—
Dew point44°
Sun, 2567° / 47°0.02
67 °
Boulder Hill, Sunday, 25 October
Light rain. High 67°, low 47°.
Pressure30.39 inHg
Wind6.6 mph W
Humidity60%
Visibility—
Dew point48°
Mon, 2659° / 49°0
59 °
Boulder Hill, Monday, 26 October
Overcast. High 59°, low 49°.
Pressure30.30 inHg
Wind9.1 mph NE
Humidity38%
Visibility—
Dew point32°
Tue, 2750° / 33°0.27
50 °
Boulder Hill, Tuesday, 27 October
Rain. High 50°, low 33°.
Pressure30.27 inHg
Wind15.6 mph NW
Humidity58%
Visibility—
Dew point31°
Wed, 2840° / 27°0
40 °
Boulder Hill, Wednesday, 28 October
Clear. High 40°, low 27°.
Pressure30.47 inHg
Wind11.4 mph NW
Humidity40%
Visibility—
Dew point15°
Thu, 2948° / 28°0
48 °
Boulder Hill, Thursday, 29 October
Partly cloudy. High 48°, low 28°.
Pressure30.24 inHg
Wind11.4 mph W
Humidity36%
Visibility—
Dew point19°
Fri, 3054° / 33°0
54 °
Boulder Hill, Friday, 30 October
Clear. High 54°, low 33°.
Pressure30.12 inHg
Wind11.3 mph SW
Humidity41%
Visibility—
Dew point26°
Sat, 3160° / 41°0
60 °
Boulder Hill, Saturday, 31 October
Overcast. High 60°, low 41°.
Pressure30.15 inHg
Wind9.4 mph S
Humidity40%
Visibility—
Dew point32°
Sun, 0158° / 47°0.04
58 °
Boulder Hill, Sunday, 1 November
Light rain. High 58°, low 47°.
Pressure30.12 inHg
Wind11.5 mph S
Humidity41%
Visibility—
Dew point33°
Mon, 0255° / 50°0.08
55 °
Boulder Hill, Monday, 2 November
Light rain. High 55°, low 50°.
Pressure29.91 inHg
Wind9.8 mph NW
Humidity92%
Visibility—
Dew point50°
Tue, 0356° / 44°0
56 °
Boulder Hill, Tuesday, 3 November
Partly cloudy. High 56°, low 44°.
Pressure29.97 inHg
Wind14.4 mph NW
Humidity61%
Visibility—
Dew point40°
Wed, 0454° / 38°0
54 °
Boulder Hill, Wednesday, 4 November
Partly cloudy. High 54°, low 38°.
Pressure30.12 inHg
Wind6.6 mph N
Humidity49%
Visibility—
Dew point33°
From day 17 onward the outlook is built from 60-year climate statistics
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)
Wed, 1848° / 35°0.13
48 °
Boulder Hill, Wednesday, 18 November
Climate normal for this date — 60-year average.
Average high48°
Average low35°
Average precipitation0.13 in
Chance of precipitation28%
Record high68° (1999)
Record low11° (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.