Current weather conditions and 15 day weather forecast for O'Fallon, Missouri, USA including weather daily high/low temperature, warnings, chance of precipitation, pressure, humidity/wind chill, rain risk, wind speed, cloud, pressure, and UV index.
| 17 December 2025 Wednesday -0.6 ° C / 30.9°F ![]() Clear |
Feels Like : -4.7 ° C / 23.6°F Humidity : % 89 Pressure : 1016 mb Wind Speed : 12.6 kmph / 7.8 miles from W ![]() Visibility : 16 km Precipitation (rainfall) : 0 mm Cloud (%) : 0 |
| Date | Weather forecast | Low temperature | High temperature | Avg. temperature | Humidity | Chance of rain | UV Index | Sun Position | Moon Position | |
|---|---|---|---|---|---|---|---|---|---|---|
| 17 December 2025 Wednesday | Sunny |
1.4 ° C (34.5°F) |
14.3 ° C (57.7°F) |
7.1 ° C (44.8°F) |
% 73 | 0% | 0.4 | Sunrise:07:15 AM Sunset: 04:42 PM |
Moonrise:05:19 AM Moonset: 02:40 PM Moon Phase ( Waning Crescent ) |
|
| 18 December 2025 Thursday | Overcast |
1.7 ° C (35.1°F) |
10.3 ° C (50.5°F) |
7.5 ° C (45.5°F) |
% 84 | 0% | 0.1 | Sunrise:07:16 AM Sunset: 04:43 PM |
Moonrise:06:19 AM Moonset: 03:21 PM Moon Phase ( Waning Crescent ) |
|
| 19 December 2025 Friday | Partly Cloudy |
-3.5 ° C (25.7°F) |
2.6 ° C (36.7°F) |
-0.7 ° C (30.8°F) |
% 60 | 0% | 0.4 | Sunrise:07:17 AM Sunset: 04:43 PM |
Moonrise:07:16 AM Moonset: 04:09 PM Moon Phase ( New Moon ) |
|
| 20 December 2025 Saturday | Sunny |
2.1 ° C (35.8°F) |
11.4 ° C (52.5°F) |
5.7 ° C (42.2°F) |
% 55 | 0% | 0.4 | Sunrise:07:17 AM Sunset: 04:44 PM |
Moonrise:08:08 AM Moonset: 05:05 PM Moon Phase ( New Moon ) |
|
| 21 December 2025 Sunday | Sunny |
0 ° C (32.1°F) |
6.3 ° C (43.3°F) |
1.9 ° C (35.5°F) |
% 60 | 0% | 0 | Sunrise:07:18 AM Sunset: 04:44 PM |
Moonrise:08:53 AM Moonset: 06:06 PM Moon Phase ( Waxing Crescent ) |
|
| 22 December 2025 Monday | Partly Cloudy |
0.2 ° C (32.3°F) |
4.9 ° C (40.8°F) |
2.4 ° C (36.4°F) |
% 42 | 0% | 2 | Sunrise:07:18 AM Sunset: 04:45 PM |
Moonrise:09:31 AM Moonset: 07:10 PM Moon Phase ( Waxing Crescent ) |
|
| 23 December 2025 Tuesday | Overcast |
5 ° C (41°F) |
16.8 ° C (62.2°F) |
11.6 ° C (52.9°F) |
% 83 | 0% | 3 | Sunrise:07:19 AM Sunset: 04:45 PM |
Moonrise:10:02 AM Moonset: 08:16 PM Moon Phase ( Waxing Crescent ) |
|
| 24 December 2025 Wednesday | Partly Cloudy |
14.6 ° C (58.4°F) |
21.7 ° C (71°F) |
17.7 ° C (63.8°F) |
% 82 | 0% | 5 | Sunrise:07:19 AM Sunset: 04:46 PM |
Moonrise:10:29 AM Moonset: 09:21 PM Moon Phase ( Waxing Crescent ) |
|
| 25 December 2025 Thursday | Patchy rain nearby |
12.9 ° C (55.2°F) |
20.1 ° C (68.2°F) |
16.8 ° C (62.2°F) |
% 77 | 0% | 4 | Sunrise:07:19 AM Sunset: 04:46 PM |
Moonrise:10:54 AM Moonset: 10:26 PM Moon Phase ( Waxing Crescent ) |
|
| 26 December 2025 Friday | Partly Cloudy |
7 ° C (44.5°F) |
10.4 ° C (50.7°F) |
8.7 ° C (47.6°F) |
% 49 | 0% | 3 | Sunrise:07:20 AM Sunset: 04:47 PM |
Moonrise:11:18 AM Moonset: 11:33 PM Moon Phase ( Waxing Crescent ) |
|
| 27 December 2025 Saturday | Patchy rain nearby |
3 ° C (37.4°F) |
6 ° C (42.8°F) |
5.4 ° C (41.8°F) |
% 79 | 89% | 2 | Sunrise:07:20 AM Sunset: 04:48 PM |
Moonrise:11:41 AM Moonset: No moonset Moon Phase ( First Quarter ) |
|
| 28 December 2025 Sunday | Overcast |
3.4 ° C (38.1°F) |
7.4 ° C (45.2°F) |
4.9 ° C (40.9°F) |
% 77 | 0% | 1 | Sunrise:07:20 AM Sunset: 04:48 PM |
Moonrise:12:06 PM Moonset: 12:41 AM Moon Phase ( Waxing Gibbous ) |
|
| 29 December 2025 Monday | Patchy rain nearby |
6 ° C (42.8°F) |
14.9 ° C (58.8°F) |
10.3 ° C (50.5°F) |
% 92 | 88% | 3 | Sunrise:07:21 AM Sunset: 04:49 PM |
Moonrise:12:35 PM Moonset: 01:53 AM Moon Phase ( Waxing Gibbous ) |
|
| 30 December 2025 Tuesday | Patchy rain nearby |
8.3 ° C (46.9°F) |
9.6 ° C (49.4°F) |
9 ° C (48.3°F) |
% 85 | 85% | 2 | Sunrise:07:21 AM Sunset: 04:50 PM |
Moonrise:01:10 PM Moonset: 03:09 AM Moon Phase ( Waxing Gibbous ) |
|