O'Fallon weather
Loading live data…Drizzle,rain likely tomorrow
NWS, the American and the European model agree on a high near 98° in O'Fallon today. Tomorrow looks light drizzle around 90°, with a 6% chance of rain.
The weather map: all three models at once
NWS, American, European side by side around O'Fallon and nearby towns.Live rain radar →Next 14 hours
consensus of the three models14-day forecast
where the models agree, and where they splitO'Fallon, MO is at its warmest in Jul (average highs near 88°F) and coldest in Jan (lows around 27°F), with roughly 45 in of precipitation across the year. Below, compare what NWS, American, European forecast for O'Fallon right now, and see exactly where they disagree.
We grade every model against the weather that actually happened, so you can see which forecast model is most accurate in United States before you trust any single number.
O'Fallon climate by month
average daytime high and overnight low across a typical yearWhich forecast is most accurate in O'Fallon?
CheckWeather Score — graded against the weather that actually happened
The CheckWeather Score blends temperature, wind and rain accuracy — each measured against ERA5 (the recorded weather) over the last 30 days across 1999 cities. Lower error means a higher score. See which forecast model is most accurate in United States, how we measure forecast accuracy, or which model each weather app uses.
Where the models disagree
temperature and rain, judged separatelyThe models often agree on temperature and still split on rain — and rain is usually what decides whether a plan survives. A wide rain range means the shower is genuinely uncertain, not that the forecast is wrong.