Alta Sierra, CA climate
Alta Sierra has mild winters and warm summers. A typical July afternoon reaches 85°, a January night drops to 29°, and about 6 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Alta Sierra feels like
Winter
Spring
Summer
Fall
Alta Sierra weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 50° | 29° | 4.8" | 1.3" | 9 | 0 | 35° – 46° |
| February | 50° | 29° | 4.6" | 1.6" | 9 | 0 | 33° – 47° |
| March | 54° | 31° | 3.5" | 1.6" | 8 | 0 | 35° – 49° |
| April | 58° | 34° | 1.9" | 0.4" | 6 | 0 | 41° – 50° |
| May | 67° | 41° | 0.9" | 0 | 4 | 0 | 46° – 61° |
| June | 77° | 49° | 0.2" | 0 | 1 | 0 | 56° – 68° |
| July | 85° | 56° | 0.1" | 0 | 1 | 0 | 66° – 74° |
| August | 85° | 55° | 0.2" | 0 | 1 | 0 | 66° – 73° |
| September | 79° | 49° | 0.2" | 0 | 1 | 0 | 59° – 68° |
| October | 68° | 41° | 0.8" | 0 | 3 | 0 | 50° – 60° |
| November | 57° | 34° | 2.0" | 0.1" | 6 | 0 | 38° – 50° |
| December | 49° | 28° | 4.4" | 1.2" | 8 | 0 | 36° – 43° |
| Year | 65° | 40° | 23.5" | 6.2" | 55 | 1 |
“Wet days” have at least 0.01" of rain or melted snow. “Snow on ground” counts days with 1" or more. The 30-year range is the coldest and warmest that month’s average temperature got between 1991 and 2020.
Rain and snow in Alta Sierra
Alta Sierra gets 23 inches of rain and melted snow a year. January is the wettest month and July the driest. Rain or snow falls on about 55 days a year.
About 155 frost-free days a year
In half of years the last 32° night comes by May 11 and the first one by October 17. That leaves about 155 frost-free days for gardens, shorter than 76% of U.S. towns.
Heating and cooling a home in Alta Sierra
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Alta Sierra, 90% of that work is heating and 10% is cooling, so the furnace matters far more than the air conditioner.
Degree days measure how far each day’s average temperature falls below or rises above 65°, added up over a year. Source: NOAA station normals.
How Alta Sierra compares
Compared with every U.S. town and city on TownTapestry, each counted once.
Warmer than it used to be
The last 30 years in Alta Sierra averaged 1.9° warmer than the 1900s. The biggest change is in June (+2.5°). The shift is larger than in 90% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Alta Sierra’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. May swings the most: between 1991 and 2020 its average temperature ranged from 46° to 61°. August is the most reliable, staying within 7°.
Common questions about Alta Sierra’s climate
What is the coldest month in Alta Sierra?
December, with a typical high of 49° and a low of 28°.
What is the hottest month in Alta Sierra?
August, with a typical high of 85° and a low of 55°. About 50 days a year reach 90°.
How much snow does Alta Sierra get?
About 6 inches in a normal winter, most of it in February.
When is the first frost in Alta Sierra?
In half of years the first 32° night comes by October 17, and the last spring frost by May 11.
What is the rainiest month in Alta Sierra?
January, with 4.8 inches of rain and melted snow. The year totals 23 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Alta Sierra itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Glennville, CA (9 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.