5-day weather forecast St. Louis Sep 13, 2026
33°Weather forecast St. Louis Sunday Sep 13, 2026: overcast, temperature from 23 °C to 33 °C.
Precipitation probability 22%. Wind up to 5 m/s (gusts 7 m/s). Air humidity 37–78%, atmospheric pressure 761–763 mm Hg, UV index up to 7.
Weather Alerts
Air Quality Alert issued September 8 at 1:42AM CDT by NWS St Louis MO
Air Quality Alert
The St. Louis Clean Air Partnership has issued an air quality alert
for the St. Louis metropolitan area from 10 AM this morning to 8 PM
CDT this evening.
An Orange air quality forecast means that maximum ozone
concentrations are expected to reach levels that pose a health risk.
Adverse health effects increase as air quality deteriorates. Ground-
level ozone is an air contaminant which can cause breathing
difficulties for children, older adults, as well as persons with
respiratory problems.
Reducing outdoor physical activity is recommended. If it is a
regularly scheduled work day you are urged to consider
telecommuting, carpooling, or utilizing public transit. Avoid
excessive idling and do not top off when refueling motor vehicles.
The use of gasoline-powered lawn equipment should be reduced or
postponed until late in the day.
For more information visit the St. Louis Clean Air Partnership at
http://cleanair-stlouis.com/
For current Air Quality Index (AQI) values visit
https://www.airnow.gov/
5 days at a glance — tap a day to open it
Sunrise 06:40
Sunset 19:12
Sunset 19:12
Waxing Crescent8% illuminated
Moonrise 09:26 · Moonset 20:16
Moonrise 09:26 · Moonset 20:16
Chart
Table
Sun, Sep 13, 2026
| Time | Weather | Temperature | Rain chance | Cloud cover | Humidity | Pressure | Wind | UV Index |
|---|---|---|---|---|---|---|---|---|
| 00:00 |  Overcast | 24 °C | 17% | 100% | 69% | 761 mm Hg | NNW 341° 1.69 (2) m/s | 0 |
| 01:00 |  Clear | 24 °C | 5% | 3% | 69% | 762 mm Hg | NNE 15° 1.81 (2.72) m/s | 0 |
| 02:00 | Overcast | 24 °C | 15% | 93% | 67% | 761 mm Hg | WNW 284° 1.69 (2.92) m/s | 0 |
| 03:00 | Overcast | 24 °C | 18% | 100% | 70% | 761 mm Hg | W 275° 0.81 (1.03) m/s | 0 |
| 04:00 |  Cloudy | 23 °C | 16% | 73% | 76% | 762 mm Hg | NE 47° 1.61 (2.61) m/s | 0 |
| 05:00 | Overcast | 24 °C | 18% | 100% | 69% | 761 mm Hg | SE 133° 1.11 (1.44) m/s | 0 |
| 06:00 | Overcast | 24 °C | 17% | 100% | 69% | 761 mm Hg | SSE 155° 1.69 (2.72) m/s | 0 |
| 07:00 | Overcast | 23 °C | 22% | 100% | 78% | 763 mm Hg | E 101° 1.39 (2.03) m/s | 0 |
| 08:00 |  Cloudy | 24 °C | 14% | 81% | 70% | 762 mm Hg | SW 233° 2.39 (4.42) m/s | 5 |
| 09:00 | Cloudy | 26 °C | 10% | 70% | 62% | 761 mm Hg | SSW 211° 2 (3.33) m/s | 6 |
| 10:00 | Overcast | 26 °C | 14% | 100% | 61% | 763 mm Hg | ESE 123° 2 (3.31) m/s | 6 |
| 11:00 | Overcast | 30 °C | 10% | 98% | 44% | 761 mm Hg | S 181° 2.89 (3.39) m/s | 7 |
| 12:00 | Cloudy | 32 °C | 5% | 64% | 37% | 761 mm Hg | SSW 206° 2.89 (3.42) m/s | 7 |
| 13:00 | Cloudy | 33 °C | 5% | 67% | 38% | 761 mm Hg | S 187° 3.81 (5.53) m/s | 7 |
| 14:00 | Overcast | 32 °C | 7% | 78% | 39% | 761 mm Hg | SSW 203° 4.19 (6) m/s | 7 |
| 15:00 | Cloudy | 32 °C | 8% | 89% | 40% | 761 mm Hg | SW 220° 4.61 (6.5) m/s | 7 |
| 16:00 | Overcast | 31 °C | 10% | 100% | 42% | 761 mm Hg | WSW 237° 5 (7) m/s | 7 |
| 17:00 | Overcast | 31 °C | 10% | 100% | 44% | 761 mm Hg | SW 226° 4 (6) m/s | 7 |
| 18:00 | Overcast | 31 °C | 11% | 100% | 47% | 761 mm Hg | SW 215° 3 (5) m/s | 7 |
| 19:00 | Overcast | 30 °C | 11% | 100% | 50% | 761 mm Hg | SSW 204° 2 (4.03) m/s | 7 |
| 20:00 | Overcast | 30 °C | 12% | 99% | 53% | 761 mm Hg | SSW 205° 2 (3.81) m/s | 0 |
| 21:00 | Overcast | 29 °C | 13% | 97% | 56% | 761 mm Hg | SSW 207° 1.89 (3.61) m/s | 0 |
| 22:00 | Overcast | 29 °C | 13% | 96% | 59% | 761 mm Hg | SSW 209° 1.89 (3.33) m/s | 0 |
| 23:00 |  Partly cloudy | 28 °C | 11% | 76% | 61% | 761 mm Hg | SSW 199° 1.89 (3.39) m/s | 0 |
Sun, Sep 13, 2026
St. Louis on the map
Data Sources & Methodology
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