Penn Valley, CA climate
Penn Valley has mild winters and hot summers. A typical July afternoon reaches 93°, a January night drops to 38°, and snow is almost unheard of.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Penn Valley feels like
Winter
Spring
Summer
Fall
Penn Valley 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 | 55° | 38° | 7.2" | 0 | 12 | 0 | 42° – 53° |
| February | 58° | 40° | 7.3" | 0 | 11 | 0 | 42° – 55° |
| March | 61° | 42° | 6.3" | 0 | 11 | 0 | 44° – 59° |
| April | 67° | 44° | 3.3" | 0 | 7 | 0 | 49° – 60° |
| May | 76° | 51° | 1.9" | 0 | 5 | 0 | 54° – 71° |
| June | 85° | 57° | 0.5" | 0 | 2 | 0 | 66° – 76° |
| July | 93° | 63° | 0.0" | 0 | 0 | 0 | 74° – 82° |
| August | 91° | 62° | 0.1" | 0 | 0 | 0 | 74° – 81° |
| September | 86° | 59° | 0.4" | 0 | 1 | 0 | 68° – 77° |
| October | 75° | 51° | 2.1" | 0 | 4 | 0 | 59° – 70° |
| November | 62° | 43° | 4.4" | 0 | 8 | 0 | 45° – 59° |
| December | 54° | 38° | 7.7" | 0 | 12 | 0 | 43° – 50° |
| Year | 72° | 49° | 41.2" | 0.0" | 74 | 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 Penn Valley
Penn Valley gets 41 inches of rain and melted snow a year. December is the wettest month and July the driest. Rain or snow falls on about 74 days a year.
About 233 frost-free days a year
In half of years the last 32° night comes by April 3 and the first one by November 24. That leaves about 233 frost-free days for gardens, longer than 87% of U.S. towns.
Heating and cooling a home in Penn Valley
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Penn Valley, 72% of that work is heating and 28% 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.
How Penn Valley 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 Penn Valley averaged 0.8° warmer than the 1900s. The biggest change is in September (+1.8°). The shift is smaller than in 86% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Penn Valley’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 54° to 71°. August is the most reliable, staying within 7°.
Common questions about Penn Valley’s climate
What is the coldest month in Penn Valley?
January, with a typical high of 55° and a low of 38°.
What is the hottest month in Penn Valley?
July, with a typical high of 93° and a low of 63°. About 66 days a year reach 90°.
How much snow does Penn Valley get?
Almost none. A normal year brings 0.0 inches.
When is the first frost in Penn Valley?
In half of years the first 32° night comes by November 24, and the last spring frost by April 3.
What is the rainiest month in Penn Valley?
December, with 7.7 inches of rain and melted snow. The year totals 41 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Penn Valley itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Harry L Englebright Dam, CA (5 mi, snow) and Colfax, CA (15 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.