Rio Vista, CA climate
Rio Vista has mild winters and warm summers, with very little rain. A typical July afternoon reaches 91°, a January night drops to 39°, and snow is almost unheard of.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Rio Vista feels like
Winter
Spring
Summer
Fall
Rio Vista 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° | 39° | 3.5" | 0 | 11 | 0 | 43° – 52° |
| February | 62° | 42° | 3.1" | 0 | 9 | 0 | 49° – 58° |
| March | 67° | 45° | 2.5" | 0 | 8 | 0 | 50° – 62° |
| April | 72° | 48° | 1.2" | 0 | 4 | 0 | 55° – 64° |
| May | 80° | 53° | 0.6" | 0 | 3 | 0 | 60° – 73° |
| June | 87° | 57° | 0.2" | 0 | 1 | 0 | 68° – 75° |
| July | 91° | 59° | 0.0" | 0 | 0 | 0 | 72° – 79° |
| August | 91° | 59° | 0.0" | 0 | 0 | 0 | 72° – 79° |
| September | 88° | 57° | 0.1" | 0 | 0 | 0 | 69° – 76° |
| October | 79° | 52° | 0.8" | 0 | 1 | 0 | 62° – 71° |
| November | 66° | 44° | 1.7" | 0 | 5 | 0 | 49° – 59° |
| December | 56° | 39° | 3.3" | 0 | 9 | 0 | 44° – 53° |
| Year | 75° | 50° | 16.9" | 0.0" | 50 | 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 Rio Vista
Rio Vista gets 17 inches of rain and melted snow a year. January is the wettest month and July the driest. Rain or snow falls on about 50 days a year.
A year-round growing season
Heating and cooling a home in Rio Vista
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Rio Vista, 62% of that work is heating and 38% 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 Rio Vista 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 Rio Vista averaged 1.5° warmer than the 1900s. The biggest change is in January (+2.2°). The shift is larger than in 71% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Rio Vista’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 60° to 73°. June is the most reliable, staying within 7°.
Common questions about Rio Vista’s climate
What is the coldest month in Rio Vista?
December, with a typical high of 56° and a low of 39°.
What is the hottest month in Rio Vista?
July, with a typical high of 91° and a low of 59°. About 64 days a year reach 90°.
How much snow does Rio Vista get?
Almost none. A normal year brings 0.0 inches.
When is the first frost in Rio Vista?
Frost is uncommon. Only 81% of years see a night at 32° or below.
What is the rainiest month in Rio Vista?
January, with 3.5 inches of rain and melted snow. The year totals 17 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Rio Vista itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Antioch Pumping Plt #3, CA (14 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.