Etna, CA climate
Etna has mild winters and warm summers. A typical July afternoon reaches 90°, a January night drops to 29°, and about 4 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Etna feels like
Winter
Spring
Summer
Fall
Etna 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 | 46° | 29° | 4.4" | 0.4" | 13 | 0 | 32° – 43° |
| February | 50° | 30° | 3.3" | 0 | 11 | 0 | 33° – 46° |
| March | 56° | 32° | 2.7" | 1.1" | 13 | 0 | 37° – 50° |
| April | 62° | 35° | 1.7" | 0.3" | 10 | 0 | 43° – 54° |
| May | 72° | 41° | 1.5" | 0 | 8 | 0 | 49° – 64° |
| June | 81° | 47° | 0.7" | 0 | 4 | 0 | 59° – 72° |
| July | 90° | 54° | 0.4" | 0 | 3 | 0 | 64° – 77° |
| August | 90° | 53° | 0.3" | 0 | 2 | 0 | 67° – 75° |
| September | 83° | 47° | 0.4" | 0 | 2 | 0 | 61° – 70° |
| October | 69° | 39° | 1.5" | 0 | 6 | 0 | 50° – 59° |
| November | 52° | 33° | 2.8" | 1.1" | 11 | 0 | 34° – 48° |
| December | 43° | 28° | 4.4" | 1.5" | 13 | 0 | 33° – 40° |
| Year | 66° | 39° | 23.9" | 4.4" | 96 | 0 |
“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 Etna
Etna gets 24 inches of rain and melted snow a year. December is the wettest month and August the driest. Rain or snow falls on about 96 days a year.
About 135 frost-free days a year
In half of years the last 32° night comes by May 20 and the first one by October 5. That leaves about 135 frost-free days for gardens, shorter than 92% of U.S. towns.
Heating and cooling a home in Etna
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Etna, 92% of that work is heating and 8% 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 Etna 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 Etna averaged 1.5° warmer than the 1900s. The biggest change is in January (+2.7°). The shift is larger than in 72% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Etna’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 49° to 64°. December is the most reliable, staying within 7°.
Common questions about Etna’s climate
What is the coldest month in Etna?
December, with a typical high of 43° and a low of 28°.
What is the hottest month in Etna?
July, with a typical high of 90° and a low of 54°. About 33 days a year reach 90°.
How much snow does Etna get?
About 4 inches in a normal winter, most of it in December.
When is the first frost in Etna?
In half of years the first 32° night comes by October 5, and the last spring frost by May 20.
What is the rainiest month in Etna?
December, with 4.4 inches of rain and melted snow. The year totals 24 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Etna itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Callahan, CA (9 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.