San Mateo, NM climate
San Mateo has chilly winters and warm summers, with very little rain. A typical July afternoon reaches 84°, a January night drops to 15°.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in San Mateo feels like
Winter
Spring
Summer
Fall
San Mateo weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
| Month | High | Low | Rain + melt | 30-yr range |
|---|---|---|---|---|
| January | 42° | 15° | 0.7" | 22° – 35° |
| February | 46° | 19° | 0.5" | 27° – 38° |
| March | 55° | 24° | 0.6" | 36° – 44° |
| April | 62° | 30° | 0.6" | 42° – 51° |
| May | 72° | 39° | 0.5" | 51° – 61° |
| June | 83° | 49° | 0.5" | 62° – 70° |
| July | 84° | 54° | 2.2" | 65° – 73° |
| August | 81° | 52° | 2.4" | 64° – 70° |
| September | 75° | 45° | 1.4" | 56° – 63° |
| October | 65° | 34° | 0.8" | 46° – 54° |
| November | 52° | 23° | 0.7" | 31° – 44° |
| December | 42° | 15° | 0.7" | 22° – 35° |
| Year | 63° | 33° | 11.5" |
“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 San Mateo
San Mateo gets 12 inches of rain and melted snow a year. August is the wettest month and February the driest.
About 129 frost-free days a year
In half of years the last 32° night comes by May 24 and the first one by October 1. That leaves about 129 frost-free days for gardens, shorter than 95% of U.S. towns.
Heating and cooling a home in San Mateo
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In San Mateo, 93% of that work is heating and 7% 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 San Mateo 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 San Mateo averaged 1.4° warmer than the 1900s. The biggest change is in March (+2.5°). The shift is larger than in 62% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at San Mateo’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. November swings the most: between 1991 and 2020 its average temperature ranged from 31° to 44°. August is the most reliable, staying within 6°.
Common questions about San Mateo’s climate
What is the coldest month in San Mateo?
January, with a typical high of 42° and a low of 15°.
What is the hottest month in San Mateo?
July, with a typical high of 84° and a low of 54°. About 31 days a year reach 90°.
When is the first frost in San Mateo?
In half of years the first 32° night comes by October 1, and the last spring frost by May 24.
What is the rainiest month in San Mateo?
August, with 2.4 inches of rain and melted snow. The year totals 12 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for San Mateo itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Grants Milan Municipal Airport, NM (19 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.