O'Fallon, MO Weather Forecast
St. Charles County, Missouri
Live radar, warnings and storm tracking for O'Fallon, with free alerts the moment it counts.
The next few hours
Taller, warmer bars mean heavier rain. Dotted means no reading for that hour.
Hour by hour
Sunrise and sunset
Next five days, scored 0 to 100The first day or two use the HRRR and NBM cloud layers. Later days only have total cloud, so treat them as a rough guide.
Know when sunset at this place will be worth a photo
We score every sunrise and sunset here from the cloud, haze and smoke forecast, and let you know when one is likely to light up. Sunrise the evening before, sunset a few hours ahead.
Seven-day outlook
Free alerts for O'Fallon
Every NWS warning, pushed to your phone, inbox or webhook the moment it is issued.
O'Fallon, MO at a glance
O'Fallon is home to about 94,074 people in St. Charles County, across 31 square miles. It ranks 7th by population of 211 places in Missouri with a forecast here. The nearest neighbour with its own forecast is Dardenne Prairie, 3 miles away.
- County
- St. Charles County
- Population
- 94,074 2023 est.
- Land area
- 31 sq mi
- People per sq mi
- 3,082
- Forecast point
- 38.7847°N, 90.7207°W
How well can the network see O'Fallon?
The nearest Doppler radar is KLSX (St. Louis, MO), to the SSE. Its lowest scan passes about 310 ft above O'Fallon. That is about as close as US radar coverage gets: low-level rotation and gust fronts over O'Fallon show up clearly. O'Fallon is closer to its radar than 98% of US cities.
The closest weather station is KSUS (St Louis/Spirit of St Louis Arpt). Representative on most days, though a thunderstorm can hit one and miss the other.
Forecasts near O'Fallon
- Dardenne Prairie, MO3 mi
- Lake St. Louis, MO4 mi
- Cottleville, MO4 mi
- St. Paul, MO5 mi
- St. Peters, MO6 mi
- Weldon Spring, MO6 mi
- Wentzville, MO8 mi
- St. Charles, MO11 mi
Elsewhere in Missouri
Kansas CitySt. LouisSpringfieldColumbiaIndependenceLee's SummitAll Missouri forecasts →