Average Weather in Los Alamos New Mexico, United States
In Los Alamos, the summers are warm and partly cloudy and the winters are chilly, dry, and mostly clear. Over the course of the year, the temperature typically varies from 23°F to 82°F and is rarely below 12°F or above 89°F.
The warm season lasts for 3.6 months, from May 27 to September 15, with an average daily high temperature above 73°F. The hottest day of the year is July 4, with an average high of 82°F and low of 60°F.
The cold season lasts for 3.1 months, from November 20 to February 23, with an average daily high temperature below 48°F. The coldest day of the year is December 30, with an average low of 23°F and high of 39°F.
Average High and Low Temperature
The figure below shows you a compact characterization of the entire year of hourly average temperatures. The horizontal axis is the day of the year, the vertical axis is the hour of the day, and the color is the average temperature for that hour and day.
Average Hourly Temperature
In Los Alamos, 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 in Los Alamos begins around August 30 and lasts for 2.3 months, ending around November 10. On September 29, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 79% of the time, and overcast or mostly cloudy 21% of the time.
The cloudier part of the year begins around November 10 and lasts for 9.6 months, ending around August 30. On February 15, the cloudiest day of the year, the sky is overcast or mostly cloudy 40% of the time, and clear, mostly clear, or partly cloudy 60% of the time.
Cloud Cover Categories
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. The chance of wet days in Los Alamos varies throughout the year.
The wetter season lasts 2.1 months, from July 6 to September 8, with a greater than 22% chance of a given day being a wet day. The chance of a wet day peaks at 35% on July 31.
The drier season lasts 9.9 months, from September 8 to July 6. The smallest chance of a wet day is 8% on January 28.
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 in Los Alamos changes throughout the year.
Rain alone is the most common for 10 months, from February 2 to December 14. The highest chance of a day with rain alone is 35% on July 31.
Snow alone is the most common for 4.3 weeks, from December 16 to January 15. The highest chance of a day with snow alone is 4% on January 6.
Mixed snow and rain is the most common for 2.9 weeks, from January 15 to February 2 and from December 14 to December 16. The highest chance of a day with mixed snow and rain is 4% on March 3.
Daily Chance of Precipitation
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 experiences some seasonal variation in monthly rainfall.
The rainy period of the year lasts for 7.7 months, from April 2 to November 23, with a sliding 31-day rainfall of at least 0.5 inches. The most rain falls during the 31 days centered around August 2, with an average total accumulation of 1.6 inches.
The rainless period of the year lasts for 4.3 months, from November 23 to April 2. The least rain falls around January 16, with an average total accumulation of 0.2 inches.
Average Monthly Rainfall
We report snowfall in liquid-equivalent terms. The actual depth of new snowfall is typically between 5 and 10 times the liquid-equivalent amount, assuming the ground is frozen. Colder, drier snow tends to be on the higher end of that range and warmer, wetter snow on the lower end.
As with rainfall, we consider the snowfall accumulated over a sliding 31-day period centered around each day of the year. Los Alamos experiences some seasonal variation in monthly liquid-equivalent snowfall.
The snowy period of the year lasts for 4.2 months, from November 15 to March 22, with a sliding 31-day liquid-equivalent snowfall of at least 0.1 inches. The most snow falls during the 31 days centered around December 26, with an average total liquid-equivalent accumulation of 0.3 inches.
The snowless period of the year lasts for 7.8 months, from March 22 to November 15. The least snow falls around July 23, with an average total liquid-equivalent accumulation of 0.0 inches.
Average Liquid-Equivalent Monthly Snowfall
The length of the day in Los Alamos varies significantly over the course of the year. In 2017, the shortest day is December 21, with 9 hours, 43 minutes of daylight; the longest day is June 20, with 14 hours, 36 minutes of daylight.
Hours of Daylight and Twilight
The earliest sunrise is at 5:48 AM on June 12, and the latest sunrise is 1 hour, 43 minutes later at 7:30 AM on November 4. The earliest sunset is at 4:51 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 in Los Alamos during 2017, starting in the spring on March 12, lasting 7.8 months, and ending in the fall on November 5.
Sunrise & Sunset with Twilight and Daylight Saving Time
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 in Los Alamos, 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.
Humidity Comfort Levels
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 in Los Alamos experiences mild seasonal variation over the course of the year.
The windier part of the year lasts for 5.3 months, from January 13 to June 22, with average wind speeds of more than 3.8 miles per hour. The windiest day of the year is April 11, with an average hourly wind speed of 4.8 miles per hour.
The calmer time of year lasts for 6.7 months, from June 22 to January 13. The calmest day of the year is August 3, with an average hourly wind speed of 2.8 miles per hour.
Average Wind Speed
The predominant average hourly wind direction in Los Alamos varies throughout the year.
The wind is most often from the south for 3.1 weeks, from July 14 to August 5, with a peak percentage of 36% on July 20. The wind is most often from the west for 11 months, from August 5 to July 14, with a peak percentage of 48% on January 1.
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 15, with an average daily incident shortwave energy per square meter above 7.3 kWh. The brightest day of the year is June 10, with an average of 8.4 kWh.
The darker period of the year lasts for 3.2 months, from November 4 to February 10, with an average daily incident shortwave energy per square meter below 4.1 kWh. The darkest day of the year is December 23, with an average of 3.0 kWh.
Average Daily Incident Shortwave Solar Energy
For the purposes of this report, the geographical coordinates of Los Alamos are 35.888 deg latitude, -106.307 deg longitude, and 7,303 ft elevation.
The topography within 2 miles of Los Alamos contains very significant variations in elevation, with a maximum elevation change of 1,424 feet and an average elevation above sea level of 7,300 feet. Within 10 miles contains very significant variations in elevation (6,178 feet). Within 50 miles also contains extreme variations in elevation (8,045 feet).
The area within 2 miles of Los Alamos is covered by shrubs (89%), within 10 miles by shrubs (57%) and trees (41%), and within 50 miles by shrubs (56%) and trees (39%).
This report illustrates the typical weather in Los Alamos, based on a statistical analysis of historical hourly weather reports and model reconstructions from January 1, 1980 to December 31, 2016.
Temperature and Dew Point
There is only a single weather station, Los Alamos County Airport, in our network suitable to be used as a proxy for the historical temperature and dew point records of Los Alamos.
At a distance of 2 kilometers from Los Alamos, closer than our threshold of 150 kilometers, this station is deemed sufficiently nearby to be relied upon as our primary source for temperature and dew point records.
The station records are corrected for the elevation difference between the station and Los Alamos according to the International Standard Atmosphere , and by the relative change present in the MERRA-2 satellite-era reanalysis between the two locations.
Please note that the station records themselves may additionally have been back-filled using other nearby stations or the MERRA-2 reanalysis.
All data relating to the Sun's position (e.g., sunrise and sunset) are computed using astronomical formulas from the book, Astronomical Tables of the Sun, Moon and Planets , by Jean Meeus.
All other weather data, including cloud cover, precipitation, wind speed and direction, and solar flux, come from NASA's MERRA-2 Modern-Era Retrospective Analysis . This reanalysis combines a variety of wide-area measurements in a state-of-the-art global meteorological model to reconstruct the hourly history of weather throughout the world on a 50-kilometer grid.
Land Use data comes from the Global Land Cover SHARE database , published by the Food and Agriculture Organization of the United Nations.
Elevation data comes from the Shuttle Radar Topography Mission (SRTM) , published by NASA's Jet Propulsion Laboratory.
Names, locations, and time zones of places and some airports come from the GeoNames Geographical Database .
Time zones for aiports and weather stations are provided by AskGeo.com .
Maps are © Esri, with data from National Geographic, Esri, DeLorme, NAVTEQ, UNEP-WCMC, USGS, NASA, ESA, METI, NRCAN, GEBCO, NOAA, and iPC.