Rocklin, CA climate
Rocklin has mild winters and hot summers. A typical July afternoon reaches 96°, a January night drops to 38°, and snow is almost unheard of.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Rocklin feels like
Winter
Spring
Summer
Fall
Rocklin 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 | 56° | 38° | 4.9" | 0 | 10 | 0 | 44° – 52° |
| February | 61° | 41° | 4.4" | 0 | 10 | 0 | 47° – 56° |
| March | 66° | 44° | 3.5" | 0 | 8 | 0 | 49° – 60° |
| April | 72° | 46° | 2.0" | 0 | 5 | 0 | 54° – 63° |
| May | 81° | 52° | 1.0" | 0 | 3 | 0 | 58° – 74° |
| June | 90° | 57° | 0.3" | 0 | 1 | 0 | 68° – 79° |
| July | 96° | 61° | 0.0" | 0 | 0 | 0 | 74° – 83° |
| August | 95° | 60° | 0.0" | 0 | 1 | 0 | 74° – 82° |
| September | 90° | 57° | 0.2" | 0 | 1 | 0 | 70° – 77° |
| October | 79° | 50° | 1.1" | 0 | 2 | 0 | 61° – 70° |
| November | 65° | 43° | 2.6" | 0 | 5 | 0 | 46° – 59° |
| December | 56° | 38° | 4.1" | 0 | 10 | 0 | 43° – 51° |
| Year | 75° | 49° | 24.0" | 0.0" | 55 | 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 Rocklin
Rocklin gets 24 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 286 frost-free days a year
In half of years the last 32° night comes by February 25 and the first one by December 5. That leaves about 286 frost-free days for gardens, longer than 94% of U.S. towns.
Heating and cooling a home in Rocklin
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Rocklin, 66% of that work is heating and 34% is cooling.
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.
Rocklin and its neighbors
Rocklin borders 4 towns with climate data. January nights across them vary by 0.6°. Loomis has the coldest January nights (38°) and Lincoln the hottest July afternoons (96°). Rocklin’s January low is 38° and its July high 96°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How Rocklin 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 Rocklin averaged 1.0° warmer than the 1900s. The biggest change is in September (+1.7°). The shift is smaller than in 69% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Rocklin’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 58° to 74°. September is the most reliable, staying within 7°.
Common questions about Rocklin’s climate
What is the coldest month in Rocklin?
January, with a typical high of 56° and a low of 38°.
What is the hottest month in Rocklin?
July, with a typical high of 96° and a low of 61°. About 63 days a year reach 90°.
How much snow does Rocklin get?
Almost none. A normal year brings 0.0 inches.
When is the first frost in Rocklin?
In half of years the first 32° night comes by December 5, and the last spring frost by February 25.
What is the rainiest month in Rocklin?
January, with 4.9 inches of rain and melted snow. The year totals 24 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Rocklin itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Represa, CA (9 mi, snow) and Auburn, CA (11 mi, frost, heat and degree days). Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.