5-day weather forecast St. Louis 20-08-2026

Weather forecast St. Louis Thursday, August 20 20.08.2026: sunny, temperature from 20 °C to 30 °C.

Precipitation probability 29%. Wind up to 4.69 m/s (gusts 9.5 m/s). Air humidity 44–90%, atmospheric pressure 761–763 mm Hg, UV index up to 7.9.

Sunrise 06:19
Sunset 19:48
First Quarter58% illuminated
Moonrise 15:08 · Moonset Does not set today
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Table

Forecast from 20 °C to 30 °C and precipitation

Temperature & Precipitation
Time00:0001:0002:0003:0004:0005:0006:0007:0008:0009:0010:0011:0012:0013:0014:0015:0016:0017:0018:0019:0020:0021:0022:0023:00
Temperature (°C)212121212020202021232527282930302929282625242322
Precipitation (mm/hr)000000000000000000000000

Cloud cover and precipitation probability

Cloud cover & Rain chance
Time00:0001:0002:0003:0004:0005:0006:0007:0008:0009:0010:0011:0012:0013:0014:0015:0016:0017:0018:0019:0020:0021:0022:0023:00
Cloud cover (%)0990004254000000510000000
Rain chance (%)13291313131313129643321111234677

Wind speed and direction

Wind & Wind gust
Time00:0001:0002:0003:0004:0005:0006:0007:0008:0009:0010:0011:0012:0013:0014:0015:0016:0017:0018:0019:0020:0021:0022:0023:00
Wind (m/s)2.52.312.191.891.311.692.112.312.392.392.1933.894.114.694.694.54.313.893.312.612.892.892.69
Wind gust (m/s)5.335.194.614.222.812.393.424.394.033.613.033.814.694.645.034.839.58.314.224.224.926.0365.5
Wind direction (°)ENE 58°NE 56°ENE 62°E 80°E 85°NE 45°NE 43°NE 37°NE 39°NE 35°NE 43°NE 35°NE 37°NE 42°NE 45°NE 48°NE 53°ENE 58°ENE 60°ENE 61°ENE 58°ENE 63°ENE 61°ENE 61°

Air humidity

Humidity
Time00:0001:0002:0003:0004:0005:0006:0007:0008:0009:0010:0011:0012:0013:0014:0015:0016:0017:0018:0019:0020:0021:0022:0023:00
Humidity (%)899089898990908779716460575046444446515866727474

Atmospheric pressure

Pressure
Time00:0001:0002:0003:0004:0005:0006:0007:0008:0009:0010:0011:0012:0013:0014:0015:0016:0017:0018:0019:0020:0021:0022:0023:00
Pressure (mm Hg)761761761761761761761762762762763763762762762762762762762762762762763763

Ultraviolet index

UV Index
Time00:0001:0002:0003:0004:0005:0006:0007:0008:0009:0010:0011:0012:0013:0014:0015:0016:0017:0018:0019:0020:0021:0022:0023:00
UV Index00000000.20.723.85.87.47.97.45.83.81.90.80.20000

Air quality & pollen

Air quality
Time00:0001:0002:0003:0004:0005:0006:0007:0008:0009:0010:0011:0012:0013:0014:0015:0016:0017:0018:0019:0020:0021:0022:0023:00
PM2.5 (µg/m³)5.83.82.41.92.43.54.14.73.74.45.66.15.95.24.74.34.144.14.75.45.65.55.3
PM10 (µg/m³)6.13.92.522.53.74.44.93.94.75.96.46.15.54.94.54.24.14.24.85.55.75.55.4
Ozone (O₃) (µg/m³)58575348444241455774891011121191221211171101008977645551
NO₂ (µg/m³)20.114.312.813.113.31312.711.8107.75.74.23.12.31.91.82.33.65.57.610.313.315.315.7
SO₂ (µg/m³)2.21.61.31.21.1111.21.92.83.53.63.43.232.82.62.42.32.11.91.71.61.5
CO (µg/m³)159164155140132139153163166166164160154149145143146157172190211233250258

St. Louis on the map

Data Sources & Methodology

Our weather forecasts are powered by a professional weather data provider that aggregates data from national weather services, satellite observations, radar networks, and over 80,000 weather stations worldwide. Forecast data is updated multiple times daily. We convert raw data into clear summaries — wind speed in m/s, pressure in mmHg — so you can plan your day with confidence.