Monte Rio, CA climate
Monte Rio has warm winters and cool summers, with plenty of rain. A typical July afternoon reaches 76°, a January night drops to 41°, and snow is almost unheard of.
NOAA 1991-2020 climate normals Updated once a decade4° warmer than normal today. The forecast high is 78°, and a typical Oct 1 in Monte Rio peaks around 74°.Live forecast: National Weather Service · Normal: NOAA 1991–2020
What a year in Monte Rio feels like
Winter
Spring
Summer
Fall
Monte Rio 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 | 58° | 41° | 9.8" | 0 | 14 | 0 | 46° – 53° |
| February | 60° | 42° | 9.6" | 0 | 13 | 0 | 46° – 56° |
| March | 62° | 42° | 6.7" | 0 | 12 | 0 | 47° – 57° |
| April | 65° | 44° | 3.5" | 0 | 8 | 0 | 49° – 57° |
| May | 69° | 47° | 1.5" | 0 | 5 | 0 | 54° – 61° |
| June | 74° | 49° | 0.4" | 0 | 1 | 0 | 59° – 64° |
| July | 76° | 51° | 0.0" | 0 | 0 | 0 | 61° – 67° |
| August | 77° | 52° | 0.1" | 0 | 0 | 0 | 61° – 68° |
| September | 77° | 50° | 0.2" | 0 | 1 | 0 | 60° – 68° |
| October | 73° | 48° | 2.1" | 0 | 4 | 0 | 57° – 66° |
| November | 64° | 43° | 5.4" | 0 | 9 | 0 | 47° – 57° |
| December | 57° | 40° | 10.4" | 0 | 13 | 0 | 45° – 54° |
| Year | 67° | 46° | 49.6" | 0.0" | 81 | 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 Monte Rio
Monte Rio gets 50 inches of rain and melted snow a year. December is the wettest month and July the driest. Rain or snow falls on about 81 days a year.
A year-round growing season
Heating and cooling a home in Monte Rio
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Monte Rio, 88% of that work is heating and 12% 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 Monte Rio 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 Monte Rio averaged 1.3° warmer than the 1900s. The biggest change is in January (+2.0°). The shift is larger than in 60% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Monte Rio’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. March swings the most: between 1991 and 2020 its average temperature ranged from 47° to 57°. June is the most reliable, staying within 5°.
Common questions about Monte Rio’s climate
What is the coldest month in Monte Rio?
December, with a typical high of 57° and a low of 40°.
What is the hottest month in Monte Rio?
August, with a typical high of 77° and a low of 52°. About 15 days a year reach 90°.
How much snow does Monte Rio get?
Almost none. A normal year brings 0.0 inches.
When is the first frost in Monte Rio?
Frost is uncommon. Only 67% of years see a night at 32° or below.
What is the rainiest month in Monte Rio?
December, with 10.4 inches of rain and melted snow. The year totals 50 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Monte Rio itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Santa Rosa, CA (17 mi, snow) and Occidental, CA (7 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.