Los Alamos, NM climate
Los Alamos has chilly, snowy winters and warm summers, with very little rain. A typical July afternoon reaches 85°, a January night drops to 19°, and about 42 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Los Alamos feels like
Winter
Spring
Summer
Fall
Los Alamos 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 | 42° | 19° | 0.8" | 9.9" | 6 | 20 | 26° – 37° |
| February | 47° | 23° | 0.7" | 8.8" | 7 | 14 | 29° – 41° |
| March | 56° | 29° | 0.8" | 5.9" | 7 | 4 | 38° – 47° |
| April | 63° | 34° | 0.8" | 3.3" | 6 | 0 | 44° – 54° |
| May | 73° | 42° | 1.1" | 0.1" | 7 | 0 | 53° – 64° |
| June | 84° | 52° | 1.1" | 0 | 7 | 0 | 63° – 72° |
| July | 85° | 57° | 2.6" | 0 | 13 | 0 | 68° – 75° |
| August | 83° | 55° | 2.7" | 0 | 15 | 0 | 66° – 73° |
| September | 77° | 48° | 1.7" | 0 | 9 | 0 | 57° – 66° |
| October | 65° | 37° | 1.3" | 1.7" | 7 | 1 | 48° – 56° |
| November | 52° | 27° | 0.8" | 4.4" | 5 | 3 | 31° – 46° |
| December | 42° | 19° | 0.9" | 8.0" | 6 | 14 | 26° – 36° |
| Year | 64° | 37° | 15.2" | 42.1" | 90 | 55 |
“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 Los Alamos
Los Alamos gets 15 inches of rain and melted snow a year. August is the wettest month and February the driest. Rain or snow falls on about 90 days a year. Snow covers the ground about 55 days of the year.
About 162 frost-free days a year
In half of years the last 32° night comes by May 2 and the first one by October 12. That leaves about 162 frost-free days for gardens, shorter than 69% of U.S. towns.
Heating and cooling a home in Los Alamos
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Los Alamos, 94% of that work is heating and 6% 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 Los Alamos 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 Los Alamos averaged 1.4° warmer than the 1900s. The biggest change is in March (+2.7°). The shift is larger than in 65% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Los Alamos’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 46°. August is the most reliable, staying within 7°.
Common questions about Los Alamos’s climate
What is the coldest month in Los Alamos?
January, with a typical high of 42° and a low of 19°.
What is the hottest month in Los Alamos?
July, with a typical high of 85° and a low of 57°. About 5 days a year reach 90°.
How much snow does Los Alamos get?
About 42 inches in a normal winter, most of it in January.
When is the first frost in Los Alamos?
In half of years the first 32° night comes by October 12, and the last spring frost by May 2.
What is the rainiest month in Los Alamos?
August, with 2.7 inches of rain and melted snow. The year totals 15 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Los Alamos itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Los Alamos, NM (3 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.