San Rafael receives its highest rainfall in Dec, while humidity peaks during winter months.
🌧️ Wettest:Dec — 122 mm☀️ Driest:Jul — 1 mm
💧 Humidity peaks at 84% in Jan · annual avg 77%
🌍 Climate Summary
Avg Annual Temp:60.3°F
Avg Annual Rainfall:619 mm
Avg Humidity:77%
Data Period:1981 – 2025
San Rafael Climate Overview
San Rafael has a warm temperate climate with warm summers and mild winters.
Temperatures peak in Sep and drop to their lowest in Dec,
while rainfall is highest during winter months.
Humidity remains high throughout the year, especially during winter months, creating warm and humid conditions.
📈 Yearly Trends
The warmest year in San Rafael's recorded history was 2014
(avg: 63.5°F),
while the coldest year was 1982
(avg: 57.4°F),
based on annual average temperatures.
📊 Key Climate Trends
🌡️ San Rafael's temperature has remained relatively stable over the past decade
📈 Minimum temperatures show a slight warming trend in recent years
🌧️ Rainfall varies year-to-year without a clear long-term trend
🌡️ Annual Temperature Trend
View Range:
Average annual high/low · Last 10 years · °F
San Rafael's temperatures has remained relatively stable over the past decade.
The highest recorded temperature reached
102.3°F in Sep 2020,
while the lowest dropped to
26.4°F in Feb 1989.
🌧️ Annual Precipitation
View Range:
Total annual precipitation · Last 10 years · mm/year
Annual rainfall in San Rafael shows noticeable variation. Rainfall varies year-to-year without a clear long-term trend.
Based on 45 years of data (1981–2025), Sep is typically the hottest month in San Rafael, California, with average high temperatures around 89.7°F.
What is the coldest month in San Rafael?▼
Dec is the coldest month in San Rafael, with average low temperatures around 35.5°F.
What is the rainiest month in San Rafael?▼
Dec receives the most rainfall with approximately 122 mm, while Jul is the driest with 1 mm.
What was the highest temperature ever recorded in San Rafael?▼
The highest recorded temperature was 102.3°F in Sep 2020. This is part of the historical record spanning 1981–2025.
What was the lowest temperature ever recorded in San Rafael?▼
The lowest recorded temperature was 26.4°F in Feb 1989.
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 Rafael get?▼
San Rafael receives the most sunlight in Jun with an average solar radiation of 7.99 kWh/m²/day. This solar radiation data, sourced from NASA POWER, is useful for solar energy planning, agriculture, and understanding seasonal sunshine availability in California.
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.