St. Helena (CA) Weather and Climate: A Comprehensive Guide
St. Helena experiences great temperature shifts.
The city's weather can transition from very warm days
to mild weather.
It receives a moderate amount of precipitation.
Let’s explore the climate details in depth to provide you with a complete overview.
Average maximum day and minimum night temperature
The climate in St. Helena is known for significant temperature differences throughout the year, making the weather dynamic. On average, daytime temperatures range from a very warm 32°C in July to a moderate 14°C in January.
Nighttime temperatures can drop, with average lows reaching 4°C in January. Check out our detailed temperature page for more information.Temperature ranges by month
Precipitation and rainy days
Generally, St. Helena receives mid-range precipitation levels, with 800 mm annually. The seasons in St. Helena, bring significant changes in precipitation. The wettest month, December, receives heavy rainfall, with an average of 175 mm of precipitation. This rainfall is distributed across 14 rainy days. In contrast, the driest month, August, experiences much less rainfall, totaling 0 mm over 0 rainy days. These distinct seasonal differences provide diverse experiences throughout the year. For more details, please visit our St. Helena Precipitation page.The mean monthly precipitation over the year, including rain, hail and snow
The average number of days each month with precipitation
Sunshine over the year
In St. Helena, summer days are longer and more sunny, with daily sunshine hours peaking at 10.3 hours in May. As the darker season arrives, the brightness of the sun becomes less. December sees a soft sun for only 5.3 hours per average day. Visit our detailed sunshine hours page for more information.Monthly hours of sunshine
Daily hours of sunshine
Daily percentage of sunshine
overcast and heavy rain overcast and heavy rain overcast and rainForecast for St. Helena (CA)
2 m/s
2 m/s
3 m/s
The best time of year to visit St. Helena in the United States of America
During the months of April, May and October you are most likely to experience good weather with pleasant average temperatures that fall between 20°C and 26°C.Other facts from our historical weather data:
Most rainfall (rainy season) is seen in February and December.
Yes, the months of June, July, August and September are very dry.
July has an average maximum temperature of 32°C and is the warmest month of the year.
The coldest month is December with an average maximum temperature of 14°C.
December tops the wettest month list with 175 mm of rainfall.
August is the driest month with 0 mm of precipitation.
May is the sunniest month with an average of 310 hours of sunshine.
No idea where to travel to this year? We have a tool that recommends destinations based on your ideal conditions. Find out where to go with our weather planner.
