Today | Weather | Monday, October 12, 2026

Weather in St. Peters, Missouri

08:08 PM
Now
Night
81° F
Feels Like 79°
Precipitation 0 %
Wind 8 mph
Humidity 52 %
Today
Sunny Weather
Day 95°
Night 66°
Precipitation 0 %
Wind 11 mph
UV Index (0 - 11+) 4

St. Peters Weather Forecast Updated

Weather Forecast History
Last Year's Weather on This Day (October 12, 2025)
Cloudy Weather

Day

81°

Night

61°

Wind

7 mph

UV Index

40

Precipitation

0 %

Air Quality in St. Peters

NOW
40 AQI
Good air quality Dominant pollutant: O3

Pollutant Concentrations:

PM2.5 4.08 µg/m³
PM10 6.44 µg/m³
O3 0.044 ppm
NO2 0.6 ppb
SO2 0.1 ppb
CO 0.09 ppm
NH3 0.76 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)
PM2.5 – 4.08 µg/m³
PM10 – 6.44 µg/m³
O3 – 85.5 µg/m³
NO2 – 1.06 µg/m³
SO2 – 0.3 µg/m³
CO – 100.06 µg/m³
NH3 – 0.76 µg/m³
NO – 0 µg/m³