As of 17:14 CDT

Weather in O'Fallon, MO

74°Current weather

O'Fallon, Wednesday, 14 October, 17:14

Light rain. Feels like 75°. High 76°, low 69°.

Pressure30.03 inHg
Wind3.4 mph NW
Humidity84%
Visibility6.2 mi
Dew point69°

Monthly outlook for O'Fallon, MO: average high 68.1°, average low 51.7°. That is 2.1° above the climate normal for October. Precipitation is expected on 5 days (about 0.9 inches), against a normal of 4 days and 1.7 inches. The warmest day looks like 23 October (84.1°), the coolest 26 October (40.7°).

68.1°/51.7°
Average high / low
+2.1°
Above normal
5 / 4
Wet days / normal
0.9 in
Precipitation this month

Ten-day blocks vs climate normal

PeriodForecast highNormalDifference
14 October – 23 October71.1°65.8°+3°
24 October – 2 November63°61.7°+0.8°
3 November – 12 Novemberat normal56.7°—

October records over 66 years

91.9°10 October 1963All-time high
28.8°24 October 1981All-time low
Thu, 1579° / 63°0.59Rain
79 °Rain

O'Fallon, Thursday, 15 October

Rain. High 79°, low 63°.

Pressure29.97 inHg
Wind8.2 mph S
Humidity94%
Visibility3.1 mi
Dew point72°
Fri, 1661° / 51°0.06Light rain
61 °Light rain

O'Fallon, Friday, 16 October

Light rain. High 61°, low 51°.

Pressure30.24 inHg
Wind17.7 mph NW
Humidity51%
Visibility6.2 mi
Dew point38°
Sat, 1757° / 43°0Clear
57 °Clear

O'Fallon, Saturday, 17 October

Clear. High 57°, low 43°.

Pressure30.56 inHg
Wind3.8 mph N
Humidity55%
Visibility6.2 mi
Dew point38°
Sun, 1861° / 43°0Clear
61 °Clear

O'Fallon, Sunday, 18 October

Clear. High 61°, low 43°.

Pressure30.50 inHg
Wind4.9 mph SE
Humidity49%
Visibility6.2 mi
Dew point38°
Mon, 1964° / 43°0Overcast
64 °Overcast

O'Fallon, Monday, 19 October

Overcast. High 64°, low 43°.

Pressure30.39 inHg
Wind4.2 mph SE
Humidity46%
Visibility—
Dew point39°
Tue, 2073° / 47°0Overcast
73 °Overcast

O'Fallon, Tuesday, 20 October

Overcast. High 73°, low 47°.

Pressure30.27 inHg
Wind5 mph SE
Humidity49%
Visibility—
Dew point47°
Wed, 2179° / 56°0Clear
79 °Clear

O'Fallon, Wednesday, 21 October

Clear. High 79°, low 56°.

Pressure30.18 inHg
Wind9.2 mph S
Humidity44%
Visibility—
Dew point51°
Thu, 2277° / 67°0.04Light rain
77 °Light rain

O'Fallon, Thursday, 22 October

Light rain. High 77°, low 67°.

Pressure30.06 inHg
Wind14.2 mph SW
Humidity52%
Visibility—
Dew point57°
Fri, 2384° / 64°0.01Light rain
84 °Light rain

O'Fallon, Friday, 23 October

Light rain. High 84°, low 64°.

Pressure30.03 inHg
Wind8 mph S
Humidity53%
Visibility—
Dew point60°
Sat, 2476° / 57°0Overcast
76 °Overcast

O'Fallon, Saturday, 24 October

Overcast. High 76°, low 57°.

Pressure30.00 inHg
Wind16.3 mph SW
Humidity63%
Visibility—
Dew point60°
Sun, 2562° / 46°0Overcast
62 °Overcast

O'Fallon, Sunday, 25 October

Overcast. High 62°, low 46°.

Pressure30.39 inHg
Wind11.5 mph NW
Humidity30%
Visibility—
Dew point27°
Mon, 2661° / 41°0Partly cloudy
61 °Partly cloudy

O'Fallon, Monday, 26 October

Partly cloudy. High 61°, low 41°.

Pressure30.42 inHg
Wind6.6 mph NW
Humidity26%
Visibility—
Dew point22°
Tue, 2760° / 44°0Overcast
60 °Overcast

O'Fallon, Tuesday, 27 October

Overcast. High 60°, low 44°.

Pressure30.24 inHg
Wind6.2 mph S
Humidity27%
Visibility—
Dew point24°
Wed, 2853° / 48°0.15Light rain
53 °Light rain

O'Fallon, Wednesday, 28 October

Light rain. High 53°, low 48°.

Pressure30.09 inHg
Wind7.2 mph S
Humidity57%
Visibility—
Dew point38°
Thu, 2966° / 45°0Overcast
66 °Overcast

O'Fallon, Thursday, 29 October

Overcast. High 66°, low 45°.

Pressure30.06 inHg
Wind7 mph W
Humidity54%
Visibility—
Dew point45°
From day 17 onward the outlook is built from 60-year climate statistics
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)
Mon, 0958° / 43°0.11Climate normal
58 °Climate normal

O'Fallon, Monday, 9 November

Climate normal for this date — 60-year average.

Average high58°
Average low43°
Average precipitation0.11 in
Chance of precipitation28%
Record high78° (2022)
Record low10° (1991)
Tue, 1056° / 41°0.12Climate normal
56 °Climate normal

O'Fallon, Tuesday, 10 November

Climate normal for this date — 60-year average.

Average high56°
Average low41°
Average precipitation0.12 in
Chance of precipitation27%
Record high75° (2012)
Record low19° (2018)
Wed, 1154° / 38°0.09Climate normal
54 °Climate normal

O'Fallon, Wednesday, 11 November

Climate normal for this date — 60-year average.

Average high54°
Average low38°
Average precipitation0.09 in
Chance of precipitation28%
Record high76° (1964)
Record low21° (2019)
Thu, 1252° / 37°0.09Climate normal
52 °Climate normal

O'Fallon, Thursday, 12 November

Climate normal for this date — 60-year average.

Average high52°
Average low37°
Average precipitation0.09 in
Chance of precipitation22%
Record high72° (2010)
Record low11° (2019)

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.