San Tan Valley receives its highest rainfall in Aug, while humidity peaks during winter months.
🌧️ Wettest:Aug — 56 mm☀️ Driest:Jun — 5 mm
💧 Humidity peaks at 49% in Jan · annual avg 37%
🌍 Climate Summary
Avg Annual Temp:70.3°F
Avg Annual Rainfall:339 mm
Avg Humidity:37%
Data Period:1981 – 2025
San Tan Valley Climate Overview
San Tan Valley has a warm subtropical climate with warm summers and cold winters.
Temperatures peak in Jul and drop to their lowest in Jan,
while rainfall is highest during summer months.
Humidity remains relatively low throughout the year, especially during winter months, creating cold and dry conditions.
📈 Yearly Trends
The warmest year in San Tan Valley's recorded history was 2025
(avg: 74.3°F),
while the coldest year was 1991
(avg: 67.1°F),
based on annual average temperatures.
📊 Key Climate Trends
🌡️ San Tan Valley's temperature shows a slight warming trend over the past decade
📈 Minimum temperatures show a slight warming trend in recent years
🌧️ Rainfall has increased noticeably in recent years compared to earlier periods
🌡️ Annual Temperature Trend
View Range:
Average annual high/low · Last 10 years · °F
San Tan Valley's temperatures shows a slight warming trend over the past decade.
The highest recorded temperature reached
119°F in Jul 1995,
while the lowest dropped to
16.6°F in Dec 1990.
🌧️ Annual Precipitation
View Range:
Total annual precipitation · Last 10 years · mm/year
Annual rainfall in San Tan Valley shows noticeable variation. Rainfall has increased noticeably in recent years compared to earlier periods.
Based on 45 years of data (1981–2025), Jul is typically the hottest month in San Tan Valley, Arizona, with average high temperatures around 111°F.
What is the coldest month in San Tan Valley?▼
Jan is the coldest month in San Tan Valley, with average low temperatures around 28°F.
What is the rainiest month in San Tan Valley?▼
Aug receives the most rainfall with approximately 56 mm, while Jun is the driest with 5 mm.
What was the highest temperature ever recorded in San Tan Valley?▼
The highest recorded temperature was 119°F in Jul 1995. This is part of the historical record spanning 1981–2025.
What was the lowest temperature ever recorded in San Tan Valley?▼
The lowest recorded temperature was 16.6°F in Dec 1990.
How many years of data does this page cover?▼
This page covers 45 years of climate data from 1981 to 2025. As new data is added to the database the page automatically reflects the updated coverage.
How much sunlight does San Tan Valley get?▼
San Tan Valley receives the most sunlight in Jun with an average solar radiation of 8.28 kWh/m²/day. This solar radiation data, sourced from NASA POWER, is useful for solar energy planning, agriculture, and understanding seasonal sunshine availability in Arizona.
Where does this weather data come from?▼
All climate data is sourced from NASA POWER (Prediction Of Worldwide Energy Resources), based on MERRA-2 satellite and model data. It provides monthly averages for temperature, precipitation, humidity, wind speed, and solar radiation.
📚 Data Source
All weather data is sourced from NASA POWER (Prediction of Worldwide Energy Resources), a NASA project providing solar and meteorological data for renewable energy, building efficiency, and agricultural research.