Los Alamos, New Mexico climate: Normal weather by month, frost dates and records
Los Alamos's normal year runs from 21°F January nights to 83°F July afternoons, with 17.5 inches of precipitation and 42 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 9.9°C, January lows of −6°C, July highs of 28°C, 444 mm of precipitation a year.
- NOAA stationLos Alamos
- Station IDUSC00295084
- Location35.86°N 106.32°W
- Elevation7,424 ft (2,263 m)
- Population (census place)13,471
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Los Alamos.
- Jan 40° 21°
- Feb 45° 24°
- Mar 53° 30°
- Apr 61° 35°
- May 70° 44°
- Jun 81° 54°
- Jul 83° 57°
- Aug 80° 55°
- Sep 74° 49°
- Oct 63° 38°
- Nov 50° 28°
- Dec 40° 21°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like in Los Alamos each month?
July is the warmest month, with normal highs of 83°F; January the coldest, with normal lows of 21°F. The most precipitation falls in August (3.20 in), the least in February (0.72 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 40°F | 21°F | 30.4°F | 0.90 | 9.9 | 6 | <1 | 30 | 10 h |
| February | 45°F | 24°F | 34.1°F | 0.72 | 8.8 | 7 | <1 | 26 | 10 h 50 min |
| March | 53°F | 30°F | 41.5°F | 1.04 | 5.9 | 7 | <1 | 22 | 11 h 50 min |
| April | 61°F | 35°F | 48.2°F | 0.93 | 3.3 | 6 | <1 | 12 | 13 h |
| May | 70°F | 44°F | 57.2°F | 1.17 | 0.1 | 7 | <1 | 2 | 14 h |
| June | 81°F | 54°F | 67.2°F | 1.17 | 0.0 | 7 | 2 | <1 | 14 h 30 min |
| July | 83°F | 57°F | 69.6°F | 2.94 | 0.0 | 13 | 2 | <1 | 14 h 20 min |
| August | 80°F | 55°F | 67.3°F | 3.20 | 0.0 | 15 | <1 | <1 | 13 h 30 min |
| September | 74°F | 49°F | 61.5°F | 2.02 | 0.0 | 9 | <1 | 1 | 12 h 30 min |
| October | 63°F | 38°F | 50.6°F | 1.58 | 1.7 | 7 | <1 | 7 | 11 h 20 min |
| November | 50°F | 28°F | 39.1°F | 0.95 | 4.4 | 5 | <1 | 22 | 10 h 20 min |
| December | 40°F | 21°F | 30.5°F | 0.87 | 8.0 | 6 | <1 | 30 | 9 h 40 min |
| Year (annual) | 62°F | 38°F | 49.8°F | 17.49 | 42.1 | 90 | 5 | 150 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 5°C | −6°C | −0.9°C | 23 mm | 25 cm |
| February | 7°C | −5°C | 1.2°C | 18 mm | 22 cm |
| March | 12°C | −1°C | 5.3°C | 26 mm | 15 cm |
| April | 16°C | 2°C | 9.0°C | 24 mm | 8 cm |
| May | 21°C | 7°C | 14.0°C | 30 mm | 0 cm |
| June | 27°C | 12°C | 19.6°C | 30 mm | 0 cm |
| July | 28°C | 14°C | 20.9°C | 75 mm | 0 cm |
| August | 26°C | 13°C | 19.6°C | 81 mm | 0 cm |
| September | 23°C | 10°C | 16.4°C | 51 mm | 0 cm |
| October | 17°C | 4°C | 10.3°C | 40 mm | 4 cm |
| November | 10°C | −2°C | 3.9°C | 24 mm | 11 cm |
| December | 5°C | −6°C | −0.8°C | 22 mm | 20 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00295084; annual normals. Wet days: 0.01 inch or more; 90°F days and freezing nights: NOAA's day counts. Daylight: sunrise to sunset on the 15th, computed from the latitude.
When is the best weather to visit Los Alamos?
Normal highs sit between 65°F and 85°F in May, June, July, August and September. Of those, May has the fewest days with rain (7).
That is a measurement, not a recommendation: it counts the months whose normal afternoon high sits between 65°F and 85°F, where a light layer is enough by day.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00295084.
When is the last frost in Los Alamos?
In Los Alamos, the last spring frost (32°F) comes after May 2 in half of years and after May 17 in one year in ten; the first autumn frost comes before October 12 in half of years and before October 1 in one year in ten.
Frost-free in half of yearsFrost in 1 to 9 years out of 10Frost most years
- Last spring frost, half of years after
- May 21 year in 10 after May 17; 9 in 10 after April 19
- First autumn frost, half of years before
- October 121 year in 10 before October 1; 9 in 10 before October 25
NOAA puts the median frost-free season at 162 days, and the season without a hard freeze (28°F) at 182 days.
A hard freeze (28°F) comes after April 20 in half of springs and before October 23 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Los Alamos in zone 7b in ZIP code 87547, the nearest ZIP area.
Frost dates for every NOAA station in New Mexico · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00295084; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026. A 10% date means one year in ten has a frost after it in spring or before it in autumn.
How hot and how cold does it get in Los Alamos?
In a normal year in Los Alamos, 5 days a year reach 90°F, 150 nights fall to 32°F or colder and 90 days bring measurable precipitation.
- Days at 90°F or more
- 5a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 150a normal year
- Days that stay below freezing
- 16high of 32°F or less
- Days with 0.01 inch of precipitation
- 90a normal year
- Days with 1 inch of snow or more
- 13a normal year
The highest temperature in this station's record (since 1918) is 98°F, on July 11, 2020; the lowest is −18°F, on January 13, 1963.
The wettest calendar year on that record is 1952, with 28.40 in; the snowiest season is 1986–87, with 153.2 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00295084; records: ACIS (NOAA Regional Climate Centers), station USC00295084. Records use complete months only; a month missing more than three days is left out.
How sunny is Los Alamos?
Over a year 86% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Los Alamos, 5.5 kWh per square metre a day. June is the sunniest month (90%) and December the cloudiest (81%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 83% | 3.2 |
| February | 82% | 4.1 |
| March | 85% | 5.6 |
| April | 85% | 6.8 |
| May | 87% | 7.7 |
| June | 90% | 8.1 |
| July | 85% | 7.2 |
| August | 86% | 6.6 |
| September | 87% | 5.8 |
| October | 88% | 4.7 |
| November | 86% | 3.5 |
| December | 81% | 2.8 |
Source: NASA POWER solar climatology, 2001-2020 (CERES SYN1deg). Satellite-based, for the 1-degree cell (about 100 km across) around the station, so it describes the area rather than the airport.
How much heating and cooling does Los Alamos need?
A normal year in Los Alamos brings 5,929 heating degree days, 10% more than the median U.S. place (5,373), and 397 cooling degree days, 56% fewer than the median (908). Seven months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 2,451 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,073 | 0 |
| February | 867 | 0 |
| March | 729 | 0 |
| April | 504 | 0 |
| May | 256 | 15 |
| June | 44 | 110 |
| July | 9 | 152 |
| August | 22 | 93 |
| September | 131 | 27 |
| October | 448 | 0 |
| November | 776 | 0 |
| December | 1,071 | 0 |
| Year (annual) | 5,929 | 397 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00295084. A degree day is one degree of a day's mean temperature below 65°F (heating) or above it (cooling); utilities use them to estimate energy use.
Has Los Alamos been warmer than normal lately?
2025 averaged 52.2°F, 2.4°F above the 1991-2020 normal of 49.8°F. 4 of the 4 complete years since 2022 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2022 | 49.9°F | +0.1°F | 18.75 | 29.5 |
| 2023 | 50.4°F | +0.6°F | 12.71 | 37.6 |
| 2024 | 51.6°F | +1.8°F | 17.72 | 52.9 |
| 2025 | 52.2°F | +2.4°F | 16.98 | 14.5 |
Source: observed years: ACIS, station USC00295084. A year counts only with all twelve months complete.
How does Los Alamos's climate compare?
Los Alamos is warmer than 22 of the other 97 places with their own NOAA record in New Mexico, and wetter than 84. Across the 7,247 U.S. stations with normals, its annual mean of 49.8°F is warmer than 39%.
In the Köppen classification computed from these normals, Los Alamos is Dfb: continental, no dry season, warm summer. What the classes mean.
Places with the most similar year elsewhere
Measured month by month on the normal high, low and precipitation, among places of 20,000 or more people in other states:
Source: NOAA NCEI 1991-2020 normals for every station PlainClimate covers. Similarity: the root-mean-square difference of the 36 monthly figures, precipitation weighted so an inch counts like 6°F.
Which places near Los Alamos share this climate record?
White Rock has no NOAA station with 1991-2020 normals of its own, and this station is the nearest full record. A place's own climate can differ from these figures, by several degrees where it sits much higher or lower than the station, nearer the coast, or inside a large city's heat; for the larger places the next nearest records are named with their yearly mean, so the spread around them is visible, and places of 50,000 or more have their own page with NOAA's gridded normals.
- White Rock, NM5,568 people · 7 mi SE
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
What do Los Alamos's other NOAA stations record?
One more NOAA station keeps 1991-2020 normals in or near Los Alamos. This page uses Los Alamos; the other differs by site and elevation:
| Station | From this station | Elevation | Year | Jan low | Jul high | Precip. | Snow | Last frost |
|---|---|---|---|---|---|---|---|---|
| Los Alamos (13 mi W) USW00003062 | 11 mi W | 8,716 ft | 40.3°F | 9°F | 74°F | 25.5 | – | June 10 |
Source: NOAA NCEI 1991-2020 normals for each station. Last frost: the median last spring date of 32°F.
Questions about Los Alamos's climate
What is the coldest month in Los Alamos?
January, with a normal high of 40°F and a normal low of 21°F. The warmest is July (83°F by day, 57°F at night).
Does it snow in Los Alamos?
Yes: 42 inches in a normal year, falling on 19 days with 0.1 inch or more, the most in January (9.9 inches).
What is the rainiest month in Los Alamos?
August, with 3.20 in of precipitation in a normal year; the driest is February with 0.72 in.
What plant hardiness zone is Los Alamos in?
The USDA's 2023 map puts Los Alamos in zone 7b in ZIP code 87547, the nearest ZIP area.
How late can frost come in Los Alamos?
In half of years the last 32°F night comes after May 2; in one year in ten it comes after May 17. Waiting until May 17 leaves about a one-in-ten chance of a later frost.
Nearby and next
- New Mexico climateThe statewide normals and every place in the state
- Cochiti, NM16 miles from this station, 55.9°F a year
- Española, NM17 miles from this station, 52.3°F a year
- Jemez Springs, NM21 miles from this station, 52.1°F a year
- Santa Fe, NM22 miles from this station, 52.0°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made