As of 06:53 CDT

Weather in O'Fallon, MO

59°Current weather

O'Fallon, Saturday, 10 October, 06:53

Partly cloudy. Feels like 58°. High 83°, low 57°.

Pressure30.03 inHg
Wind2 mph E
Humidity75%
Visibility6.2 mi
Dew point51°

Monthly outlook for O'Fallon, MO: average high 70.3°, average low 51.2°. That is 2.3° above the climate normal for October. Precipitation is expected on 4 days (about 1.2 inches), against a normal of 4 days and 1.7 inches. The warmest day looks like 13 October (91.7°), the coolest 18 October (32.1°).

70.3°/51.2°
Average high / low
+2.3°
Above normal
4 / 4
Wet days / normal
1.2 in
Precipitation this month

Ten-day blocks vs climate normal

PeriodForecast highNormalDifference
10 October – 19 October73.1°67.1°+3.4°
20 October – 29 October65.5°63.4°+1.1°
30 October – 8 Novemberat normal59.1°—

October records over 66 years

91.9°10 October 1963All-time high
28.8°24 October 1981All-time low
Sun, 1188° / 50°0Clear
88 °Clear

O'Fallon, Sunday, 11 October

Clear. High 88°, low 50°.

Pressure29.97 inHg
Wind3 mph S
Humidity45%
Visibility6.2 mi
Dew point55°
Mon, 1292° / 68°0Clear
92 °Clear

O'Fallon, Monday, 12 October

Clear. High 92°, low 68°.

Pressure29.88 inHg
Wind11.1 mph SW
Humidity38%
Visibility6.2 mi
Dew point59°
Tue, 1392° / 73°0Clear
92 °Clear

O'Fallon, Tuesday, 13 October

Clear. High 92°, low 73°.

Pressure29.88 inHg
Wind8.8 mph W
Humidity47%
Visibility6.2 mi
Dew point65°
Wed, 1477° / 71°0.48Rain
77 °Rain

O'Fallon, Wednesday, 14 October

Rain. High 77°, low 71°.

Pressure30.03 inHg
Wind8.4 mph NE
Humidity83%
Visibility—
Dew point70°
Thu, 1570° / 61°0.34Rain
70 °Rain

O'Fallon, Thursday, 15 October

Rain. High 70°, low 61°.

Pressure30.21 inHg
Wind12.4 mph N
Humidity74%
Visibility—
Dew point58°
Fri, 1671° / 53°0Overcast
71 °Overcast

O'Fallon, Friday, 16 October

Overcast. High 71°, low 53°.

Pressure30.00 inHg
Wind15.3 mph NW
Humidity31%
Visibility—
Dew point37°
Sat, 1749° / 40°0Light rain
49 °Light rain

O'Fallon, Saturday, 17 October

Light rain. High 49°, low 40°.

Pressure30.27 inHg
Wind19.5 mph NW
Humidity51%
Visibility—
Dew point27°
Sun, 1851° / 32°0Clear
51 °Clear

O'Fallon, Sunday, 18 October

Clear. High 51°, low 32°.

Pressure30.50 inHg
Wind13.2 mph NW
Humidity36%
Visibility—
Dew point21°
Mon, 1958° / 36°0Mostly clear
58 °Mostly clear

O'Fallon, Monday, 19 October

Mostly clear. High 58°, low 36°.

Pressure30.39 inHg
Wind7.4 mph S
Humidity37%
Visibility—
Dew point27°
Tue, 2063° / 41°0Overcast
63 °Overcast

O'Fallon, Tuesday, 20 October

Overcast. High 63°, low 41°.

Pressure30.30 inHg
Wind7.6 mph S
Humidity33%
Visibility—
Dew point28°
Wed, 2170° / 43°0Clear
70 °Clear

O'Fallon, Wednesday, 21 October

Clear. High 70°, low 43°.

Pressure30.24 inHg
Wind9.1 mph S
Humidity29%
Visibility—
Dew point31°
Thu, 2273° / 48°0Clear
73 °Clear

O'Fallon, Thursday, 22 October

Clear. High 73°, low 48°.

Pressure30.09 inHg
Wind14.5 mph S
Humidity28%
Visibility—
Dew point34°
Fri, 2361° / 54°0.11Light rain
61 °Light rain

O'Fallon, Friday, 23 October

Light rain. High 61°, low 54°.

Pressure29.97 inHg
Wind14.3 mph S
Humidity80%
Visibility—
Dew point53°
Sat, 2466° / 49°0.24Rain
66 °Rain

O'Fallon, Saturday, 24 October

Rain. High 66°, low 49°.

Pressure29.83 inHg
Wind14.5 mph NW
Humidity72%
Visibility—
Dew point54°
Sun, 2560° / 42°0Overcast
60 °Overcast

O'Fallon, Sunday, 25 October

Overcast. High 60°, low 42°.

Pressure29.97 inHg
Wind10.4 mph NW
Humidity38%
Visibility—
Dew point32°
From day 17 onward the outlook is built from 60-year climate statistics
Mon, 2661° / 46°0.13Climate normal
61 °Climate normal

O'Fallon, Monday, 26 October

Climate normal for this date — 60-year average.

Average high61°
Average low46°
Average precipitation0.13 in
Chance of precipitation35%
Record high83° (1963)
Record low30° (1962)
Tue, 2762° / 46°0.09Climate normal
62 °Climate normal

O'Fallon, Tuesday, 27 October

Climate normal for this date — 60-year average.

Average high62°
Average low46°
Average precipitation0.09 in
Chance of precipitation20%
Record high80° (2023)
Record low33° (2001)
Wed, 2861° / 46°0.05Climate normal
61 °Climate normal

O'Fallon, Wednesday, 28 October

Climate normal for this date — 60-year average.

Average high61°
Average low46°
Average precipitation0.05 in
Chance of precipitation23%
Record high78° (1999)
Record low31° (1969)
Thu, 2962° / 46°0.13Climate normal
62 °Climate normal

O'Fallon, Thursday, 29 October

Climate normal for this date — 60-year average.

Average high62°
Average low46°
Average precipitation0.13 in
Chance of precipitation28%
Record high82° (2024)
Record low30° (2017)
Fri, 3063° / 47°0.12Climate normal
63 °Climate normal

O'Fallon, Friday, 30 October

Climate normal for this date — 60-year average.

Average high63°
Average low47°
Average precipitation0.12 in
Chance of precipitation30%
Record high82° (2024)
Record low29° (1980)
Sat, 3162° / 47°0.16Climate normal
62 °Climate normal

O'Fallon, Saturday, 31 October

Climate normal for this date — 60-year average.

Average high62°
Average low47°
Average precipitation0.16 in
Chance of precipitation42%
Record high80° (1968)
Record low29° (1993)
Sun, 0161° / 46°0.19Climate normal
61 °Climate normal

O'Fallon, Sunday, 1 November

Climate normal for this date — 60-year average.

Average high61°
Average low46°
Average precipitation0.19 in
Chance of precipitation28%
Record high80° (2016)
Record low26° (2023)
Mon, 0260° / 44°0.09Climate normal
60 °Climate normal

O'Fallon, Monday, 2 November

Climate normal for this date — 60-year average.

Average high60°
Average low44°
Average precipitation0.09 in
Chance of precipitation35%
Record high80° (2016)
Record low27° (1966)
Tue, 0358° / 43°0.12Climate normal
58 °Climate normal

O'Fallon, Tuesday, 3 November

Climate normal for this date — 60-year average.

Average high58°
Average low43°
Average precipitation0.12 in
Chance of precipitation30%
Record high78° (1987)
Record low19° (1991)
Wed, 0458° / 44°0.15Climate normal
58 °Climate normal

O'Fallon, Wednesday, 4 November

Climate normal for this date — 60-year average.

Average high58°
Average low44°
Average precipitation0.15 in
Chance of precipitation28%
Record high78° (1978)
Record low19° (1991)
Thu, 0557° / 43°0.17Climate normal
57 °Climate normal

O'Fallon, Thursday, 5 November

Climate normal for this date — 60-year average.

Average high57°
Average low43°
Average precipitation0.17 in
Chance of precipitation35%
Record high78° (1978)
Record low24° (1991)
Fri, 0657° / 42°0.09Climate normal
57 °Climate normal

O'Fallon, Friday, 6 November

Climate normal for this date — 60-year average.

Average high57°
Average low42°
Average precipitation0.09 in
Chance of precipitation32%
Record high77° (2023)
Record low28° (1982)
Sat, 0758° / 42°0.07Climate normal
58 °Climate normal

O'Fallon, Saturday, 7 November

Climate normal for this date — 60-year average.

Average high58°
Average low42°
Average precipitation0.07 in
Chance of precipitation13%
Record high74° (1980)
Record low15° (1991)
Sun, 0858° / 42°0.03Climate normal
58 °Climate normal

O'Fallon, Sunday, 8 November

Climate normal for this date — 60-year average.

Average high58°
Average low42°
Average precipitation0.03 in
Chance of precipitation17%
Record high82° (2023)
Record low0° (1991)

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 O'Fallon, MO 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 O'Fallon, MO 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.