Home / Local Weather & Traffic / Illinois / O Fallon / Current Weather

Current Weather in O Fallon, IL

Updated: Sun Sep 27th 2026 8:30 AM CDT

Cloudy

62^°F 16^°C

Feels Like 57^°F / 14^°C

O Fallon, IL weather condition is Cloudy and 62°F.

Today's Weather in O Fallon,IL

The current weather in O Fallon IL as of 8:30 AM CDT on Sun Sep 27th 2026, has a sky condition of Cloudy with the visibility of 6 mile(s) and the UV index at 0.2. It is 62 degrees fahrenheit but feels like 57 degrees with a forecasted high of 79 and low of 61. The barometric pressure is 30.07 - measured by inches of mercury - and is steady since its last observation. The humidity is 52 percent that's falling since the last report, with a dew point of 44 degrees fahrenheit which is falling. Wind direction is from the East at 4.7 miles per hour, gusting at 7.4 miles per hour. Sunrise was at 6:51 AM and Sunset is at 6:49 PM. The moon phase is a Waning Gibbous moon rising at 7:05 PM with 96% illumination. Thank you for listening to the weather report from LocalConditions.com!

Listen to this weather report - press Read

Barometer 30.07 inHg. rising
Humidity 52% falling
Heat Index 61°F
Wind from E. 4.7 mph
Wind Gust 7.4 miles per hour
Wind Chill 61°F
UV Index 0.2

Dew Point 44°F falling
Visibility 6 mi.
Sunrise 6:51 AM
Sunset 6:49 PM
Moonrise 7:05 PM
Moonset 7:52 AM
Moon Phase Waning Gibbous Moon 96%

Ask About Weather

Test our Weather Chatbot. It provides up to 10 days of forecast information! You can ask questions like "Will it rain tomorrow?" or "What's the fishing conditions like for the morning", or "What is the barometric pressure tonight".

Radar Alerts Next 48 Hours Traffic

Hourly Forecast - Next 8 hours

5 Day Forecast

Overcast

Overcast with a high of 79°F and a low of 61°F. 7% possible chance of rain predicted. Winds will be light at 8mph at times. Humidity levels are comfortable, sitting around 42%.

Temperature	Humidity	Rainfall	Snow	Wind
Hi 79° \| Lo 61°	42%	7%	0%	7.4 mph

Sunny

Sunny with a high of 81°F and a low of 58°F. 2% possible chance of rain predicted. Winds will be light at 8mph at times. Humidity levels are comfortable, sitting around 40%.

Temperature	Humidity	Rainfall	Snow	Wind
Hi 81° \| Lo 58°	40%	2%	0%	7.4 mph

Overcast

Overcast with a high of 89°F and a low of 62°F. 6% possible chance of rain predicted. Winds will be moderate, blowing around 11mph. Humidity levels are comfortable, sitting around 37%.

Temperature	Humidity	Rainfall	Snow	Wind
Hi 89° \| Lo 62°	37%	6%	0%	10.7 mph

Overcast

Overcast with a high of 83°F and a low of 63°F. Probable rainfall forecasted, having an 82% chance with an estimated 0.36in. Winds will be light at 8mph at times. The humidity will be on the higher side, reaching around 72%.

Temperature	Humidity	Rainfall	Snow	Wind
Hi 83° \| Lo 63°	72%	82% \| est. 0.36in	0%	7.6 mph

Overcast

Overcast with a high of 83°F and a low of 68°F. Probable rainfall forecasted, having a 72% chance with an estimated 0.13in. Winds will be moderate, blowing around 15mph. The humidity will be on the higher side, reaching around 70%.

Temperature	Humidity	Rainfall	Snow	Wind
Hi 83° \| Lo 68°	70%	72% \| est. 0.13in	0%	14.8 mph

Yesterday 5-Day 10-Day

Weather Radar Map

Live O Fallon, IL weather with granular precipitation, radar, barometric pressure, temperatures and wind speeds for today thru Thursday, as you toggle through each map layer. Use the slider to move forward and back in time to view how current data and forecasts will affect the region; you can press or click on the map to show metrics available for each tab. The related timestamp is located above the Play button which will animate the weather forecast.

Hourly Temperature

The current temperature today is 62^°F. The morning temperature of 61°^F is lowest at 7am with the daytime high of 79°^F at 3pm and a low around 69°^F at 9pm is expected.

Hourly Barometric Pressure

The highest pressure today is 30.08^inHg at 10am and lowest being 29.97^inHg at 4pm.

Hourly Wind Speeds

The fastest wind is reported to be 7.4^mph at 7pm, while the slowest is 3.1^mph around 6am; expect wind gusts peaking 15.9^mph at 5pm.

More Weather Charts

Current National Weather

Strong Nor'easter Hits Mid-Atlantic and Northeast - 09-27 to 09-29

Updated Sun Sep 27th 2026, 2:59am PDT

We're keeping a close eye on a strong Nor'easter affecting the Mid-Atlantic and Northeast through Monday night, bringing serious coastal flooding, rip currents, strong winds, and heavy rain. Meanwhile, parts of the Southwest, Great Basin, and Central/Southern Rockies face heavy rain risks on Monday. Also, the Upper Midwest may experience heavy rain on Monday as well. Let's break down what's happening over the next few days.

Mid-Atlantic and Northeast

A powerful Nor'easter is currently moving off the coast, affecting areas from New Jersey to Maine. Expect coastal flooding, especially during high tide Sunday morning, with strong wind gusts of 40-50 mph possibly causing power outages and tree damage. Heavy rain may lead to localized flooding from Northern New Jersey to Southern New England through Monday. This is due to the storm's track and the placement of cold air.

Southwest and Rockies

Look out on Monday as tropical moisture flows into the Southwest, bringing heavy rain and thunderstorms in the Great Basin and Central/Southern Rockies. The rain risk extends into the Southern High Plains on Tuesday. This is due to the influx of tropical moisture.

Upper Midwest

On Monday, a system in the Northern Plains will cause thunderstorms and heavy rain in the Upper Midwest. Localized flash flooding is possible, especially in urban areas and near small streams. This is expected as warm, moist air interacts with a passing low-pressure system.

This weather report is valid for ZIP code 62269, accurately covering the area of O Fallon, IL.