Observed 5:44 AM CDT at KSUS
O'Fallon, MO weather
Foggy and 43°6°, 9°5° warmer than a typical Oct 23.
Today: low 49°9° (likely 46°8° to 51°11°), high 76°24° (likely 73°23° to 76°24°).
Now 43°6°
Fog
- Wind
- Calm
- Up to 5 mph8 km/h through 6 PM
- Dew point
- 42°6°
- Comfortable · up to 51°11° by 9 AM
- Humidity
- 97%
- Air 43°6°, dew point 42°6° · fog or dew likely
- UV index
- 0Low
- Moderate 11 AM–4 PM · peak 4
- Air quality
- 84Moderate
- Main pollutant: PM2.5 (fine particles)
- Pressure
- 30.24 inHg1024 hPa
- Rising slowly · +0.02 inHg+0.6 hPa in 3 h
Next 2 hours
No precipitation expected in the next 2 hours.
From forecast models
Next 48 hours
This morningUp to 66°19° by 11 AM · Clear
This afternoonUp to 76°24° by 4 PM · Clear
TonightDown to 51°11° by 5 AM · Partly cloudy
Tomorrow morningUp to 66°19° by 11 AM · Mostly cloudy
Tomorrow afternoonUp to 75°24° by 3 PM · Partly cloudy
Tomorrow nightDown to 50°10° by 5 AM · Partly cloudy
| Hour | Conditions | Temperature | Feels like | Precipitation | Wind | Humidity | Cloud cover | UV index |
|---|---|---|---|---|---|---|---|---|
| Fri 6a | Clear | 48°9° (likely 47°8° to 51°11°) | 48°9° | 0% | 2 mph3 km/h from SE, gusts 5 mph8 km/h | 93% | 13% | 0 |
| Fri 7a | Sunny | 47°8° (likely 46°8° to 51°11°) | 47°8° | 0% | 2 mph3 km/h from SE, gusts 6 mph10 km/h | 100% | 13% | 0 |
| Fri 8a | Sunny | 50°10° (likely 47°8° to 53°12°) | 50°10° | 0% | 2 mph3 km/h from SE, gusts 7 mph11 km/h | 93% | 12% | 0 |
| Fri 9a | Sunny | 54°12° (likely 53°12° to 58°14°) | 54°12° | 0% | 2 mph3 km/h from SE, gusts 6 mph10 km/h | 90% | 6% | 1 |
| Fri 10a | Sunny | 62°17° (likely 60°16° to 64°18°) | 62°17° | 0% | 2 mph3 km/h from SE, gusts 9 mph14 km/h | 72% | 0% | 1 |
| Fri 11a | Sunny | 66°19° (likely 65°18° to 68°20°) | 66°19° | 0% | 3 mph5 km/h from SE, gusts 10 mph17 km/h | 63% | 0% | 3 |
| Fri 12p | Sunny | 70°21° (likely 68°20° to 72°22°) | 70°21° | 0% | 5 mph8 km/h from SE, gusts 10 mph16 km/h | 55% | 0% | 4 |
| Fri 1p | Sunny | 74°23° (likely 70°21° to 74°23°) | 74°23° | 0% | 5 mph8 km/h from SE, gusts 11 mph17 km/h | 46% | 0% | 4 |
| Fri 2p | Sunny | 75°24° (likely 72°22° to 76°24°) | 75°24° | 0% | 5 mph8 km/h from SE, gusts 9 mph14 km/h | 45% | 0% | 4 |
| Fri 3p | Sunny | 75°24° (likely 73°23° to 76°24°) | 75°24° | 0% | 5 mph8 km/h from SE, gusts 8 mph12 km/h | 45% | 0% | 3 |
| Fri 4p | Sunny | 76°24° (likely 73°23° to 76°24°) | 76°24° | 0% | 5 mph8 km/h from SE, gusts 8 mph13 km/h | 43% | 0% | 2 |
| Fri 5p | Sunny | 74°23° (likely 71°22° to 74°23°) | 74°23° | 0% | 3 mph5 km/h from SE, gusts 10 mph16 km/h | 46% | 0% | 1 |
| Fri 6p | Clear | 71°22° (likely 67°19° to 71°22°) | 71°22° | 0% | 3 mph5 km/h from SE, gusts 11 mph18 km/h | 51% | 0% | 0 |
| Fri 7p | Clear | 67°19° (likely 63°17° to 67°19°) | 67°19° | 0% | 2 mph3 km/h from SE, gusts 10 mph16 km/h | 59% | 0% | 0 |
| Fri 8p | Clear | 62°17° (likely 60°16° to 64°18°) | 62°17° | 0% | 3 mph5 km/h from SE, gusts 10 mph16 km/h | 70% | 6% | 0 |
| Fri 9p | Clear | 60°16° (likely 59°15° to 63°17°) | 60°16° | 0% | 3 mph5 km/h from SE, gusts 10 mph16 km/h | 75% | 17% | 0 |
| Fri 10p | Clear | 59°15° (likely 57°14° to 61°16°) | 59°15° | 0% | 3 mph5 km/h from SE, gusts 10 mph16 km/h | 75% | 32% | 0 |
| Fri 11p | Clear | 58°14° (likely 57°14° to 60°16°) | 58°14° | 0% | 3 mph5 km/h from SE, gusts 12 mph20 km/h | 75% | 37% | 0 |
| Sat 12a | Cloudy | 57°14° (likely 56°13° to 59°15°) | 57°14° | 0% | 3 mph5 km/h from SE, gusts 12 mph19 km/h | 75% | 72% | 0 |
| Sat 1a | Cloudy | 56°13° (likely 55°13° to 58°14°) | 56°13° | 0% | 3 mph5 km/h from SE, gusts 10 mph17 km/h | 74% | 70% | 0 |
| Sat 2a | Cloudy | 54°12° (likely 54°12° to 57°14°) | 54°12° | 0% | 3 mph5 km/h from SE, gusts 9 mph15 km/h | 77% | 68% | 0 |
| Sat 3a | Mostly clear | 54°12° (likely 52°11° to 56°13°) | 54°12° | 0% | 3 mph5 km/h from SE, gusts 8 mph13 km/h | 77% | 64% | 0 |
| Sat 4a | Mostly clear | 52°11° (likely 50°10° to 54°12°) | 52°11° | 0% | 2 mph3 km/h from SE, gusts 7 mph11 km/h | 83% | 62% | 0 |
| Sat 5a | Cloudy | 51°11° (likely 49°9° to 53°12°) | 51°11° | 0% | 2 mph3 km/h from SE, gusts 5 mph9 km/h | 83% | 78% | 0 |
| Sat 6a | Cloudy | 50°10° (likely 48°9° to 52°11°) | 50°10° | 0% | 2 mph3 km/h from SE, gusts 5 mph8 km/h | 86% | 76% | 0 |
| Sat 7a | Cloudy | 49°9° (likely 47°8° to 52°11°) | 49°9° | 0% | 2 mph3 km/h from SE, gusts 6 mph9 km/h | 89% | 73% | 0 |
| Sat 8a | Cloudy | 51°11° (likely 47°8° to 53°12°) | 51°11° | 0% | 2 mph3 km/h from SE, gusts 6 mph9 km/h | 83% | 74% | 0 |
| Sat 9a | Cloudy | 55°13° (likely 53°12° to 58°14°) | 55°13° | 0% | 2 mph3 km/h from SE, gusts 6 mph9 km/h | 83% | 77% | 1 |
| Sat 10a | Cloudy | 62°17° (likely 61°16° to 62°17°) | 62°17° | 0% | 2 mph3 km/h from SE, gusts 10 mph15 km/h | 67% | 77% | 2 |
| Sat 11a | Cloudy | 66°19° (likely 66°19° to 67°19°) | 66°19° | 0% | 3 mph5 km/h from SE, gusts 10 mph16 km/h | 61% | 74% | 3 |
| Sat 12p | Partly sunny | 70°21° (likely 70°21° to 71°22°) | 70°21° | 0% | 3 mph5 km/h from SE, gusts 9 mph15 km/h | 51% | 74% | 4 |
| Sat 1p | Cloudy | 73°23° (likely 73°23° to 74°23°) | 73°23° | 0% | 3 mph5 km/h from SE, gusts 7 mph12 km/h | 44% | 71% | 4 |
| Sat 2p | Cloudy | 74°23° (likely 74°23° to 76°24°) | 74°23° | 0% | 3 mph5 km/h from SE, gusts 7 mph11 km/h | 43% | 67% | 4 |
| Sat 3p | Partly sunny | 75°24° (likely 75°24° to 77°25°) | 75°24° | 0% | 3 mph5 km/h from SE, gusts 7 mph11 km/h | 41% | 50% | 3 |
| Sat 4p | Partly sunny | 75°24° (likely 74°23° to 76°24°) | 75°24° | 0% | 3 mph5 km/h from SE, gusts 8 mph12 km/h | 40% | 45% | 2 |
| Sat 5p | Sunny | 73°23° (likely 72°22° to 75°24°) | 73°23° | 0% | 3 mph5 km/h from SE, gusts 9 mph14 km/h | 44% | 41% | 1 |
| Sat 6p | Mostly clear | 70°21° (likely 68°20° to 70°21°) | 70°21° | 0% | 2 mph3 km/h from SE, gusts 9 mph15 km/h | 49% | 44% | 0 |
| Sat 7p | Partly cloudy | 66°19° (likely 64°18° to 66°19°) | 66°19° | 0% | 2 mph3 km/h from SE, gusts 9 mph14 km/h | 56% | 48% | 0 |
| Sat 8p | Partly cloudy | 61°16° (likely 61°16° to 64°18°) | 61°16° | 0% | 2 mph3 km/h from SE, gusts 9 mph15 km/h | 67% | 59% | 0 |
| Sat 9p | Partly cloudy | 59°15° (likely 59°15° to 62°17°) | 59°15° | 0% | 2 mph3 km/h from SE, gusts 9 mph15 km/h | 72% | 57% | 0 |
| Sat 10p | Cloudy | 58°14° (likely 57°14° to 61°16°) | 58°14° | 0% | 2 mph3 km/h from SE, gusts 9 mph14 km/h | 72% | 60% | 0 |
| Sat 11p | Cloudy | 57°14° (likely 56°13° to 60°16°) | 57°14° | 0% | 2 mph3 km/h from SE, gusts 8 mph13 km/h | 75% | 65% | 0 |
| Sun 12a | Cloudy | 56°13° (likely 54°12° to 59°15°) | 56°13° | 0% | 2 mph3 km/h from S, gusts 7 mph12 km/h | 74% | 70% | 0 |
| Sun 1a | Cloudy | 55°13° (likely 53°12° to 59°15°) | 55°13° | 0% | 2 mph3 km/h from S, gusts 6 mph10 km/h | 77% | 68% | 0 |
| Sun 2a | Partly cloudy | 54°12° (likely 52°11° to 59°15°) | 54°12° | 0% | 2 mph3 km/h from S, gusts 4 mph7 km/h | 77% | 66% | 0 |
| Sun 3a | Partly cloudy | 53°12° (likely 51°11° to 59°15°) | 53°12° | 0% | 1 mph2 km/h from S, gusts 4 mph6 km/h | 80% | 62% | 0 |
| Sun 4a | Mostly clear | 51°11° (likely 50°10° to 58°14°) | 51°11° | 0% | 1 mph2 km/h from S, gusts 3 mph5 km/h | 83% | 45% | 0 |
| Sun 5a | Partly cloudy | 50°10° (likely 48°9° to 57°14°) | 50°10° | 0% | 1 mph2 km/h from S, gusts 3 mph5 km/h | 83% | 42% | 0 |
Days ahead
Today, Oct 23. Sunny. High 76°24°, low 49°9°. Typical 67°19° / 42°6°. Dry. Mostly agree.
Morning
6 AM–noon
Sunny, 50°10°Dry
Afternoon
noon–6 PM
Sunny, 76°24°Dry
Evening
6 PM–midnight
Clear, 62°17°Dry
Overnight
midnight–6 AM
Mostly clear, 51°11°Dry
Official NWS forecast
Today: Sunny, with a high near 76. Southeast wind around 5 mph.
Tonight: Mostly clear, with a low around 49. Southeast wind around 3 mph.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
- High, likely
- 73°23°–76°24°
- Low, likely
- 46°8°–51°11°
- Typical high / low
- 67°19° / 42°6°
- Wind
- 8 mph13 km/h, gusts 18 mph29 km/h
- UV peak
- 5
Tomorrow, Oct 24. Cloudy. High 75°24°, low 49°9°. Typical 66°19° / 42°6°. Dry. Mostly agree.
Morning
6 AM–noon
Cloudy, 51°11°Dry
Afternoon
noon–6 PM
Partly sunny, 75°24°Dry
Evening
6 PM–midnight
Partly cloudy, 61°16°Dry
Overnight
midnight–6 AM
Partly cloudy, 50°10°Dry
Official NWS forecast
Day: Mostly sunny, with a high near 75. Southeast wind around 3 mph.
Night: Partly cloudy, with a low around 49. Southeast wind around 2 mph.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
- High, likely
- 75°24°–77°25°
- Low, likely
- 47°8°–52°11°
- Typical high / low
- 66°19° / 42°6°
- Wind
- 8 mph12 km/h, gusts 17 mph27 km/h
- UV peak
- 4
Sunday, Oct 25. Partly sunny. High 78°26°, low 50°10°. Typical 66°19° / 42°6°. Dry. Forecasts agree.
Morning
6 AM–noon
Cloudy, 51°11°Dry
Afternoon
noon–6 PM
Cloudy, 77°25°Dry
Evening
6 PM–midnight
Cloudy, 63°17°Dry
Overnight
midnight–6 AM
Cloudy, 56°13°Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Mostly sunny, with a high near 78. South wind around 1 mph.
Night: Mostly cloudy, with a low around 50.
Forecasts agreeIndependent forecasts are close; the range is narrow.
- High, likely
- 76°24°–79°26°
- Low, likely
- 46°8°–54°12°
- Typical high / low
- 66°19° / 42°6°
- Wind
- 6 mph10 km/h
- UV peak
- 4
Monday, Oct 26. Cloudy. High 76°24°, low 51°11°. Typical 65°18° / 41°5°. Dry. Forecasts agree.
Morning
6 AM–noon
Cloudy, 57°14°Dry
Afternoon
noon–6 PM
Cloudy, 76°25°Dry
Evening
6 PM–midnight
Cloudy, 63°17°Dry
Overnight
midnight–6 AM
Cloudy, 54°12°Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Partly sunny, with a high near 76.
Night: Mostly cloudy, with a low around 51.
Forecasts agreeIndependent forecasts are close; the range is narrow.
- High, likely
- 75°24°–77°25°
- Low, likely
- 51°11°–57°14°
- Typical high / low
- 65°18° / 41°5°
- Wind
- 8 mph12 km/h, gusts 14 mph22 km/h
- UV peak
- 4
Tuesday, Oct 27. Cloudy. High 74°23°, low 50°10°. Typical 65°18° / 41°5°. Dry. Forecasts agree.
Morning
6 AM–noon
Cloudy, 56°13°Dry
Afternoon
noon–6 PM
Cloudy, 73°23°Dry
Evening
6 PM–midnight
Cloudy, 62°17°Dry
Overnight
midnight–6 AM
Cloudy, 55°13°Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Partly sunny, with a high near 74.
Night: Mostly cloudy, with a low around 50.
Forecasts agreeIndependent forecasts are close; the range is narrow.
- High, likely
- 72°22°–74°23°
- Low, likely
- 50°10°–57°14°
- Typical high / low
- 65°18° / 41°5°
- Wind
- 8 mph14 km/h, gusts 20 mph32 km/h
- UV peak
- 3
Wednesday, Oct 28. Partly sunny. High 76°24°, low 51°11°. Typical 64°18° / 41°5°. Dry. Mostly agree.
Morning
6 AM–noon
Sunny, 56°13°Dry
Afternoon
noon–6 PM
Sunny, 77°25°Dry
Evening
6 PM–midnight
Clear, 64°18°Dry
Overnight
midnight–6 AM
Cloudy, 57°14°Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Mostly sunny, with a high near 76.
Night: Mostly clear, with a low around 51.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
- High, likely
- 75°24°–78°26°
- Low, likely
- 51°11°–57°14°
- Typical high / low
- 64°18° / 41°5°
- Wind
- 11 mph18 km/h, gusts 24 mph39 km/h
- UV peak
- 4
Thursday, Oct 29. Partly sunny. High 75°24°, low 49°9°. Typical 64°18° / 40°4°. Dry. Forecasts differ.
Morning
6 AM–noon
Cloudy, 57°14°Dry
Afternoon
noon–6 PM
Cloudy, 72°22°Dry
Evening
6 PM–midnight
Cloudy, 63°17°Dry
Overnight
midnight–6 AM
Mostly clear, 55°13°Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Mostly sunny, with a high near 75.
Night: Partly cloudy, with a low around 49.
Forecasts differIndependent forecasts disagree; expect changes and plan for the range.
- High, likely
- 69°21°–77°25°
- Low, likely
- 49°9°–59°15°
- Typical high / low
- 64°18° / 40°4°
- Wind
- 14 mph23 km/h, gusts 30 mph49 km/h
- UV peak
- 4
Friday, Oct 30. Drizzle. High 68°20°, low 52°11°. Typical 64°18° / 40°4°. Rain 0.1 in2.5 mm, 10% chance. Forecasts differ.
Morning
6 AM–noon
Sunny, 55°13°Dry
Afternoon
noon–6 PM
Sunny, 64°18°Dry
Evening
6 PM–midnight
Drizzle, 57°14°Dry
Overnight
midnight–6 AM
Rain, 52°11°20% chance · 0.03 in0.7 mm
Hours this far out come from computer models only.
The National Weather Service writes about seven days ahead; this day is our model forecast only.
Forecasts differIndependent forecasts disagree; expect changes and plan for the range.
- High, likely
- 63°17°–72°22°
- Low, likely
- 43°6°–57°14°
- Typical high / low
- 64°18° / 40°4°
- Wind
- 14 mph23 km/h, gusts 36 mph58 km/h
Saturday, Oct 31. Cloudy. High 66°19°, low 52°11°. Typical 63°17° / 40°4°. Rain 0.17 in4.3 mm, 30% chance. Mostly agree.
Morning
6 AM–noon
Rain, 54°12°30% chance · 0.04 in1.1 mm
Afternoon
noon–6 PM
Drizzle, 66°19°30% chance · 0.01 in0.3 mm
Evening
6 PM–midnight
Cloudy, 61°16°30% chance
Overnight
midnight–6 AM
Cloudy, 55°13°30% chance
Hours this far out come from computer models only.
The National Weather Service writes about seven days ahead; this day is our model forecast only.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
- High, likely
- 62°17°–68°20°
- Low, likely
- 45°7°–58°14°
- Typical high / low
- 63°17° / 40°4°
- Wind
- 13 mph20 km/h, gusts 31 mph50 km/h
Sunday, Nov 1. Cloudy. High 65°18°, low 54°12°. Typical 63°17° / 39°4°. Rain 0.16 in4.1 mm, 30% chance. Forecasts differ.
Morning
6 AM–noon
Cloudy, 55°13°30% chance · 0.02 in0.6 mm
Afternoon
noon–6 PM
Cloudy, 64°18°30% chance · 0.01 in0.3 mm
Evening
6 PM–midnight
Cloudy, 56°13°20% chance
Hours this far out come from computer models only.
The National Weather Service writes about seven days ahead; this day is our model forecast only.
Forecasts differIndependent forecasts disagree; expect changes and plan for the range.
- High, likely
- 54°12°–73°23°
- Low, likely
- 45°7°–59°15°
- Typical high / low
- 63°17° / 39°4°
- Wind
- 15 mph24 km/h, gusts 25 mph40 km/h
- UV peak
- 2
The outlook
Today
Dry, high 76°, low 49°.
Tomorrow
Dry, high 75°, low 49°.
Sunday
Dry, high 78°, low 50°, warming up.
Rest of week
Mostly dry, highs 65–76°.
Want the meteorologists’ reasoning? Read the NWS forecast discussion (LSX) (opens in a new tab)
What changed since yesterday
No meaningful changes from yesterday’s forecast.
Radar
For your home
What this week’s weather means for heating, cooling, pipes and fresh air.
Heating this week
About 85% less heating than a typical week.
Heating degree days, base 65°F
Heat-pump hours, next 7 days
- h below 47°F
- 1
- h below 17°F
- 0
- h below 5°F
- 0
47, 17 and 5°F are the test points heat pumps are rated at.
Comfort
Dry air outside (dew point 42°F).
Open the windows?
Today, 10:00 AM–9:00 PM
Good stretch to open the windows.
Is this typical?
Oct 23, today vs a typical year
Today’s expected high is 9°5° warmer than typical.
- Normal high / low
- 67°19° / 42°6°
- Forecast high / low
- 76°24° / 49°9°
- Record high
- 84°29° in 2010
- Record low
- 28°−2° in 2006
Last 7 days vs normal
On average 1° colder than normal (daily mean temperature).
- −9°−5°SatOct 17
- −5°−3°SunOct 18
- −2°−1°MonOct 19
- +1°TueOct 20
- +3°+2°WedOct 21
- +5°+3°ThuOct 22
- —FriOct 23
O'Fallon weather by month: normals, records, snow and freeze dates
Sun & moon
Sun
Sunrise 7:20 AM, sunset 6:13 PM.
- Daylight
- 10 h 53 min
- Losing 2 min 21 s a day; shortest Dec 21, 1 h 26 min less
- Golden hour
- 5:36–6:30 PM
- Morning 7:03–7:57 AM
- Blue hour
- 6:30–6:40 PM
- Morning 6:53–7:03 AM; first light 6:53 AM
Stars tonight? Unknown
Cloud forecast not available for tonight.
Moon
Waxing gibbous
91% lit · growing
- Today
- sets 4:29 AM · rises 4:44 PM
- Full moon
- Oct 25
- New moon
- Nov 9
