Average Weather at Harriet Alexander Field Airport Colorado, United States
At Harriet Alexander Field Airport, the summers are warm, the winters are freezing and windy, and it is dry and partly cloudy year round. Over the course of the year, the temperature typically varies from 18°F to 80°F and is rarely below 6°F or above 87°F.
Based on the tourism score, the best time of year to visit Harriet Alexander Field Airport for warm-weather activities is from late June to late August.
The warm season lasts for 3.5 months, from June 2 to September 17, with an average daily high temperature above 72°F. The hottest day of the year is July 8, with an average high of 80°F and low of 55°F.
The cold season lasts for 3.4 months, from November 21 to March 1, with an average daily high temperature below 46°F. The coldest day of the year is December 30, with an average low of 18°F and high of 37°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
frigid 15°F freezing 32°F very cold 45°F cold 55°F cool 65°F comfortable 75°F warm 85°F hot 95°F sweltering
At Harriet Alexander Field 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 Harriet Alexander Field Airport begins around August 30 and lasts for 2.1 months, ending around November 1. On September 29, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 77% of the time, and overcast or mostly cloudy 23% of the time.
The cloudier part of the year begins around November 1 and lasts for 9.9 months, ending around August 30. On May 6, the cloudiest day of the year, the sky is overcast or mostly cloudy 43% of the time, and clear, mostly clear, or partly cloudy 57% of the time.
Cloud Cover Categories
0% clear 20% mostly clear 40% partly cloudy 60% mostly cloudy 80% overcast 100%
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. The chance of wet days at Harriet Alexander Field Airport varies throughout the year.
The wetter season lasts 2.1 months, from July 5 to September 10, with a greater than 19% chance of a given day being a wet day. The chance of a wet day peaks at 32% on August 10.
The drier season lasts 9.9 months, from September 10 to July 5. The smallest chance of a wet day is 5% on January 12.
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 Harriet Alexander Field Airport changes throughout the year.
Rain alone is the most common for 11 months, from January 27 to December 21. The highest chance of a day with rain alone is 32% on August 10.
Snow alone is the most common for 1.2 months, from December 21 to January 27. The highest chance of a day with snow alone is 3% on December 30.
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. Harriet Alexander Field Airport experiences some seasonal variation in monthly rainfall.
The rainy period of the year lasts for 6.5 months, from April 3 to October 20, with a sliding 31-day rainfall of at least 0.5 inches. The most rain falls during the 31 days centered around August 1, with an average total accumulation of 1.3 inches.
The rainless period of the year lasts for 5.5 months, from October 20 to April 3. The least rain falls around January 11, with an average total accumulation of 0.1 inches.
Average Monthly Rainfall
The sliding 31-day liquid-equivalent quantity of snowfall at Harriet Alexander Field Airport does not vary significantly over the course of the year, staying within 0.1 inches of 0.1 inches throughout.
Average Liquid-Equivalent Monthly Snowfall
The length of the day at Harriet Alexander Field Airport varies significantly over the course of the year. In 2018, the shortest day is December 21, with 9 hours, 28 minutes of daylight; the longest day is June 21, with 14 hours, 52 minutes of daylight.
Hours of Daylight and Twilight
The earliest sunrise is at 5:39 AM on June 13, and the latest sunrise is 1 hour, 54 minutes later at 7:33 AM on November 3. The earliest sunset is at 4:42 PM on December 6, and the latest sunset is 3 hours, 50 minutes later at 8:32 PM on June 27.
Daylight saving time (DST) is observed at Harriet Alexander Field Airport during 2018, starting in the spring on March 11, lasting 7.8 months, and ending in the fall on November 4.
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 at Harriet Alexander Field 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.
Humidity Comfort Levels
dry 55°F comfortable 60°F humid 65°F muggy 70°F oppressive 75°F miserable
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 Harriet Alexander Field Airport experiences significant seasonal variation over the course of the year.
The windier part of the year lasts for 8.0 months, from October 13 to June 15, with average wind speeds of more than 8.1 miles per hour. The windiest day of the year is April 4, with an average hourly wind speed of 10.6 miles per hour.
The calmer time of year lasts for 4.0 months, from June 15 to October 13. The calmest day of the year is August 12, with an average hourly wind speed of 5.6 miles per hour.
Average Wind Speed
The predominant average hourly wind direction at Harriet Alexander Field Airport is from the west throughout the year.
Best Time of Year to Visit
To characterize how pleasant the weather is at Harriet Alexander Field 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 Harriet Alexander Field Airport for general outdoor tourist activities is from late June to late August, with a peak score in the second week of July.
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 Harriet Alexander Field Airport for hot-weather activities is from late June to early August, with a peak score in the second week of July.
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 Harriet Alexander Field Airport typically lasts for 5.1 months (156 days), from around May 6 to around October 8, rarely starting before April 20 or after May 22, and rarely ending before September 18 or after October 29.
Time Spent in Various Temperature Bands and the Growing Season
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 Harriet Alexander Field Airport should appear around April 30, only rarely appearing before April 17 or after May 14.
Growing Degree Days
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 2.5 months, from May 9 to July 25, with an average daily incident shortwave energy per square meter above 7.1 kWh. The brightest day of the year is June 14, with an average of 8.2 kWh.
The darker period of the year lasts for 3.2 months, from November 2 to February 10, with an average daily incident shortwave energy per square meter below 3.8 kWh. The darkest day of the year is December 22, with an average of 2.8 kWh.
Average Daily Incident Shortwave Solar Energy
For the purposes of this report, the geographical coordinates of Harriet Alexander Field Airport are 38.536 deg latitude, -106.051 deg longitude, and 7,352 ft elevation.
The topography within 2 miles of Harriet Alexander Field Airport contains significant variations in elevation, with a maximum elevation change of 663 feet and an average elevation above sea level of 7,341 feet. Within 10 miles contains significant variations in elevation (5,581 feet). Within 50 miles also contains extreme variations in elevation (9,203 feet).
The area within 2 miles of Harriet Alexander Field Airport is covered by cropland (41%), grassland (30%), and shrubs (29%), within 10 miles by trees (56%) and shrubs (35%), and within 50 miles by trees (42%) and shrubs (36%).
This report illustrates the typical weather at Harriet Alexander Field Airport, 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
Harriet Alexander Field Airport has a weather station that reported reliably enough during the analysis period that we have included it in our network. When available, historical temperature and dew point measurements are taken directly from this weather station. These records are obtained from NOAA's Integrated Surface Hourly data set, falling back on ICAO METAR records as required.
In the case of missing or erroneous measurements from this station, we fall back on records from nearby stations, adjusted according to typical seasonal and diurnal intra-station differences. For a given day of the year and hour of the day, the fallback station is selected to minimize the prediction error over the years for which there are measurements for both stations.
The stations on which we may fall back include but are not limited to Cottonwood Pass; Salida Mountain, Monarch Pass; Saguache Municipal Airport; Wilkerson Pass; Lake County Airport; Gunnison County Airport; Copper Mountain, Red Cliff Pass; and Aspen–Pitkin County Airport.
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.
The information on this site is provided as is, without any assurances as to its accuracy or suitability for any purpose. Weather data is prone to errors, outages, and other defects. We assume no responsibility for any decisions made on the basis of the content presented on this site.
We draw particular cautious attention to our reliance on the MERRA-2 model-based reconstructions for a number of important data series. While having the tremendous advantages of temporal and spatial completeness, these reconstructions: (1) are based on computer models that may have model-based errors, (2) are coarsely sampled on a 50 km grid and are therefore unable to reconstruct the local variations of many microclimates, and (3) have particular difficulty with the weather in some coastal areas, especially small islands.
We further caution that our travel scores are only as good as the data that underpin them, that weather conditions at any given location and time are unpredictable and variable, and that the definition of the scores reflects a particular set of preferences that may not agree with those of any particular reader.