Climate Insights for Alta Sierra

The climate in Alta Sierra is temperate. The average annual temperature is 13°C and approximately 1733mm of precipitation falls per year. January is the wettest month, receiving around 378mm of rainfall. Alta Sierra is in the Northern Hemisphere. Summer begins at the end of June and lasts through September. The summer months are: July, August, June. The coldest months are December, February, January, when temperatures can drop to 1°C. Alta Sierra experiences heavy snowfall, typically from January through December.

Temperatures in Alta Sierra vary considerably across the year, with a 31°C difference between the coldest and warmest months. The warmest month is July, when average highs reach 32°C and the mean temperature sits around 24°C. December is the coolest month, with minimum temperatures around 1°C and an average of 5°C. On average, daily temperatures fluctuate by about 13°C between overnight lows and afternoon highs. The sharpest temperature change occurs between May and June, with a 6°C shift in average temperatures.

Alta Sierra is a fairly wet location, receiving approximately 1733mm of precipitation annually, which averages out to around 144mm per month. The wettest month is January, averaging 378mm of rainfall. March and February also tend to see above-average precipitation. The driest month is July, with just 1mm. That's 377mm less than January, the wettest month. Rainfall is heavily concentrated in certain months, creating a distinct wet and dry season. Visitors should plan around these patterns, as the difference between peak and low months is dramatic. Alta Sierra receives heavy snowfall, accumulating around 343cm annually from January through December. The snowiest month is January, with approximately 97cm. Winter travel should account for significant snow cover.

Alta Sierra is relatively calm, with an average annual wind speed of 2km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is February, averaging 3km/h, though still comfortable for most outdoor activities. The calmest conditions occur in August, with average winds dropping to 2km/h, making it an ideal period for wind-sensitive activities. There is moderate seasonal variation in wind speed, with a 1km/h gap between the calmest and windiest months.

It is currently spring in Alta Sierra, which began on March 20, 2026. Alta Sierra is in the Northern Hemisphere, where spring begins in March, summer in June, autumn in September, and winter in December. The warmest period peaks in July at around 32°C, while the coldest stretch bottoms out in December near 1°C. Summer is next, beginning on June 21, 2026 — 4 days from now.

The best time to visit Alta Sierra is during June, July, August and September, when the weather is most comfortable for travellers. During these months, average temperatures hover around 22°C with modest rainfall averaging 11mm per month. By contrast, December can be quite cold with temperatures dropping to 1°C. With minimal rainfall expected, you can pack light and plan outdoor activities with confidence.

The table below shows monthly climate averages for Alta Sierra based on historical weather data. Min and max temperatures represent typical overnight lows and afternoon highs for each month, shown in degrees Celsius (°C). Precipitation is measured in millimetres (mm) and indicates the average total rainfall per month. Snow is measured in centimetres (cm) and reflects average monthly snowfall accumulation. Wind speed is the average sustained speed in kilometres per hour (km/h). All values are based on averages from over 10 years of historical weather data. The current month is highlighted for quick reference.