Climate and Average Weather Year Round at Los Alamos County Airport New Mexico, United States

At Los Alamos County Airport, the summers are warm and partly cloudy and the winters are snowy, very cold, and mostly clear. Over the course of the year, the temperature typically varies from 24°F to 83°F and is rarely below 13°F or above 90°F.

Based on the tourism score, the best time of year to visit Los Alamos County Airport for warm-weather activities is from early June to early September.

The warm season lasts for 3.6 months, from May 27 to September 15, with an average daily high temperature above 74°F. The hottest month of the year at Los Alamos County Airport is July, with an average high of 82°F and low of 61°F.

The cold season lasts for 3.1 months, from November 21 to February 23, with an average daily high temperature below 49°F. The coldest month of the year at Los Alamos County Airport is January, with an average low of 25°F and high of 41°F.

At Los Alamos County Airport, the average percentage of the sky covered by clouds experiences mild seasonal variation over the course of the year.

The clearer part of the year at Los Alamos County Airport begins around August 31 and lasts for 2.3 months, ending around November 10.

The clearest month of the year at Los Alamos County Airport is June, during which on average the sky is clear, mostly clear, or partly cloudy 77% of the time.

The cloudier part of the year begins around November 10 and lasts for 9.7 months, ending around August 31.

The cloudiest month of the year at Los Alamos County Airport is February, during which on average the sky is overcast or mostly cloudy 39% of the time.

A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. The chance of wet days at Los Alamos County Airport varies throughout the year.

The wetter season lasts 2.1 months, from July 5 to September 9, with a greater than 21% chance of a given day being a wet day. The month with the most wet days at Los Alamos County Airport is August, with an average of 9.1 days with at least 0.04 inches of precipitation.

The drier season lasts 9.9 months, from September 9 to July 5. The month with the fewest wet days at Los Alamos County Airport is January, with an average of 2.7 days with at least 0.04 inches of precipitation.

Among wet days, we distinguish between those that experience rain alone, snow alone, or a mixture of the two. Based on this categorization, the most common form of precipitation at Los Alamos County Airport changes throughout the year.

Rain alone is the most common for 11 months, from January 27 to December 23. The month with the most days of rain alone at Los Alamos County Airport is August, with an average of 9.1 days.

Snow alone is the most common for 2.6 weeks, from December 29 to January 16. The month with the most days of snow alone at Los Alamos County Airport is January, with an average of 1.0 days.

Mixed snow and rain is the most common for 2.4 weeks, from January 16 to January 27 and from December 23 to December 29. The month with the most days of mixed snow and rain at Los Alamos County Airport is December, with an average of 1.1 days.

Rainfall

To show variation within the months and not just the monthly totals, we show the rainfall accumulated over a sliding 31-day period centered around each day of the year. Los Alamos County Airport experiences some seasonal variation in monthly rainfall.

The rainy period of the year lasts for 8.2 months, from March 21 to November 27, with a sliding 31-day rainfall of at least 0.5 inches. The month with the most rain at Los Alamos County Airport is August, with an average rainfall of 1.5 inches.

The rainless period of the year lasts for 3.8 months, from November 27 to March 21. The month with the least rain at Los Alamos County Airport is January, with an average rainfall of 0.3 inches.

Snowfall

As with rainfall, we consider the snowfall accumulated over a sliding 31-day period centered around each day of the year. Los Alamos County Airport experiences some seasonal variation in monthly snowfall.

The snowy period of the year lasts for 3.8 months, from November 21 to March 14, with a sliding 31-day snowfall of at least 1.0 inches. The month with the most snow at Los Alamos County Airport is December, with an average snowfall of 2.0 inches.

The snowless period of the year lasts for 8.2 months, from March 14 to November 21. The least snow falls around July 20, with an average total accumulation of 0.0 inches.

The length of the day at Los Alamos County Airport varies significantly over the course of the year. In 2026, the shortest day is December 21, with 9 hours, 43 minutes of daylight; the longest day is June 21, with 14 hours, 36 minutes of daylight.

The earliest sunrise is at 5:48 AM on June 13, and the latest sunrise is 1 hour, 39 minutes later at 7:26 AM on October 31. The earliest sunset is at 4:50 PM on December 5, and the latest sunset is 3 hours, 35 minutes later at 8:25 PM on June 28.

Daylight saving time (DST) is observed at Los Alamos County Airport during 2026, starting in the spring on March 8, lasting 7.8 months, and ending in the fall on November 1.

The figure below presents a compact representation of key lunar data for 2026. The horizontal axis is the day, the vertical axis is the hour of the day, and the colored areas indicate when the moon is above the horizon. The vertical gray bars (new Moons) and blue bars (full Moons) indicate key Moon phases.

We base the humidity comfort level on the dew point, as it determines whether perspiration will evaporate from the skin, thereby cooling the body. Lower dew points feel drier and higher dew points feel more humid. Unlike temperature, which typically varies significantly between night and day, dew point tends to change more slowly, so while the temperature may drop at night, a muggy day is typically followed by a muggy night.

The perceived humidity level at Los Alamos County Airport, as measured by the percentage of time in which the humidity comfort level is muggy, oppressive, or miserable, does not vary significantly over the course of the year, remaining a virtually constant 0% throughout.

This section discusses the wide-area hourly average wind vector (speed and direction) at 10 meters above the ground. The wind experienced at any given location is highly dependent on local topography and other factors, and instantaneous wind speed and direction vary more widely than hourly averages.

The average hourly wind speed at Los Alamos County Airport experiences significant seasonal variation over the course of the year.

The windier part of the year lasts for 5.2 months, from January 15 to June 22, with average wind speeds of more than 7.0 miles per hour. The windiest month of the year at Los Alamos County Airport is April, with an average hourly wind speed of 8.7 miles per hour.

The calmer time of year lasts for 6.8 months, from June 22 to January 15. The calmest month of the year at Los Alamos County Airport is August, with an average hourly wind speed of 5.2 miles per hour.

The predominant average hourly wind direction at Los Alamos County Airport varies throughout the year.

The wind is most often from the south for 3.3 weeks, from July 14 to August 6, with a peak percentage of 36% on July 20. The wind is most often from the west for 11 months, from August 6 to July 14, with a peak percentage of 48% on January 1.

To characterize how pleasant the weather is at Los Alamos County Airport throughout the year, we compute two travel scores.

The tourism score favors clear, rainless days with perceived temperatures between 65°F and 80°F. Based on this score, the best time of year to visit Los Alamos County Airport for general outdoor tourist activities is from early June to early September, with a peak score in the last week of June.

The beach/pool score favors clear, rainless days with perceived temperatures between 75°F and 90°F. Based on this score, the best time of year to visit Los Alamos County Airport for hot-weather activities is from late June to late July, with a peak score in the first week of July.

Methodology

For each hour between 8:00 AM and 9:00 PM of each day in the analysis period (1980 to 2016), independent scores are computed for perceived temperature, cloud cover, and total precipitation. Those scores are combined into a single hourly composite score, which is then aggregated into days, averaged over all the years in the analysis period, and smoothed.

Our cloud cover score is 10 for fully clear skies, falling linearly to 9 for mostly clear skies, and to 1 for fully overcast skies.

Our precipitation score, which is based on the three-hour precipitation centered on the hour in question, is 10 for no precipitation, falling linearly to 9 for trace precipitation, and to 0 for 0.04 inches of precipitation or more.

Our tourism temperature score is 0 for perceived temperatures below 50°F, rising linearly to 9 for 65°F, to 10 for 75°F, falling linearly to 9 for 80°F, and to 1 for 90°F or hotter.

Our beach/pool temperature score is 0 for perceived temperatures below 65°F, rising linearly to 9 for 75°F, to 10 for 82°F, falling linearly to 9 for 90°F, and to 1 for 100°F or hotter.

Definitions of the growing season vary throughout the world, but for the purposes of this report, we define it as the longest continuous period of non-freezing temperatures (≥ 32°F) in the year (the calendar year in the Northern Hemisphere, or from July 1 until June 30 in the Southern Hemisphere).

The growing season at Los Alamos County Airport typically lasts for 6.2 months (190 days), from around April 20 to around October 27, rarely starting before April 3 or after May 8, and rarely ending before October 5 or after November 17.

Growing degree days are a measure of yearly heat accumulation used to predict plant and animal development, and defined as the integral of warmth above a base temperature, discarding any excess above a maximum temperature. In this report, we use a base of 50°F and a cap of 86°F.

Based on growing degree days alone, the first spring blooms at Los Alamos County Airport should appear around April 9, only rarely appearing before March 26 or after April 22.

This section discusses the total daily incident shortwave solar energy reaching the surface of the ground over a wide area, taking full account of seasonal variations in the length of the day, the elevation of the Sun above the horizon, and absorption by clouds and other atmospheric constituents. Shortwave radiation includes visible light and ultraviolet radiation.

The average daily incident shortwave solar energy experiences extreme seasonal variation over the course of the year.

The brighter period of the year lasts for 2.7 months, from April 24 to July 14, with an average daily incident shortwave energy per square meter above 7.3 kWh. The brightest month of the year at Los Alamos County Airport is June, with an average of 8.3 kWh.

The darker period of the year lasts for 3.1 months, from November 4 to February 9, with an average daily incident shortwave energy per square meter below 4.1 kWh. The darkest month of the year at Los Alamos County Airport is December, with an average of 3.1 kWh.

For the purposes of this report, the geographical coordinates of Los Alamos County Airport are 35.880 deg latitude, -106.273 deg longitude, and 7,142 ft elevation.

The topography within 2 miles of Los Alamos County Airport contains very significant variations in elevation, with a maximum elevation change of 896 feet and an average elevation above sea level of 7,008 feet. Within 10 miles contains very significant variations in elevation (5,407 feet). Within 50 miles also contains extreme variations in elevation (7,999 feet).

The area within 2 miles of Los Alamos County Airport is covered by shrubs (91%), within 10 miles by shrubs (67%) and trees (32%), and within 50 miles by shrubs (55%) and trees (40%).