Today | Weather | Wednesday, August 5, 2026

Weather in St. Louis, Missouri

02:04 AM
Now
Night
70° F
Feels Like 70°
Precipitation 0 %
Wind 4 mph
Humidity 79 %
Today
Cloudy Weather
Day 91°
Night 72°
Precipitation 25 %
Wind 5 mph
UV Index (0 - 11+) 9

Warning: High UV Index Today: 9

High risk of harm from unprotected sun exposure. Take precautions: wear a hat, sunglasses, and apply sunscreen regularly if you’ll be outdoors for extended periods.

St. Louis Weather Forecast Updated

Last updated on
Weather Forecast History
Last Year's Weather on This Day (August 5, 2025)
Cloudy Night

Day

88°

Night

66°

Wind

4 mph

Precipitation

3 %

Air Quality in St. Louis

NOW
35 AQI
Good air quality Dominant pollutant: PM2.5

Pollutant Concentrations:

PM2.5 8.33 µg/m³
PM10 8.73 µg/m³
O3 0.034 ppm
NO2 0.6 ppb
SO2 0.4 ppb
CO 0.11 ppm
NH3 0.24 µg/m³
NO 0 µg/m³
PM2.5 – Fine particles <2.5μm
PM10 – Inhalable particles <10μm
O3 – Ozone
NO2 – Nitrogen dioxide
SO2 – Sulfur dioxide
CO – Carbon monoxide
NH3 – Ammonia
NO – Nitric oxide

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

Show raw pollutant concentrations (µg/m³)
PM2.58.33 µg/m³
PM108.73 µg/m³
O366.86 µg/m³
NO21.19 µg/m³
SO21.1 µg/m³
CO126.11 µg/m³
NH30.24 µg/m³
NO0 µg/m³