Average Weather at Ralph M Calhoun Memorial Airport Alaska, United States
At Ralph M Calhoun Memorial Airport, the summers are comfortable and mostly cloudy and the winters are long, frigid, snowy, and partly cloudy. Over the course of the year, the temperature typically varies from -16°F to 72°F and is rarely below -46°F or above 82°F.
The warm season lasts for 3.7 months, from May 14 to September 5, with an average daily high temperature above 57°F. The hottest day of the year is June 29, with an average high of 72°F and low of 50°F.
The cold season lasts for 3.9 months, from November 8 to March 5, with an average daily high temperature below 15°F. The coldest day of the year is January 18, with an average low of -16°F and high of -0°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
At Ralph M Calhoun Memorial 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 Ralph M Calhoun Memorial Airport begins around January 10 and lasts for 6.4 months, ending around July 21. On May 16, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 46% of the time, and overcast or mostly cloudy 54% of the time.
The cloudier part of the year begins around July 21 and lasts for 5.6 months, ending around January 10. On December 8, the cloudiest day of the year, the sky is overcast or mostly cloudy 69% of the time, and clear, mostly clear, or partly cloudy 31% 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 Ralph M Calhoun Memorial Airport varies throughout the year.
The wetter season lasts 4.0 months, from May 28 to September 29, with a greater than 19% chance of a given day being a wet day. The chance of a wet day peaks at 33% on August 3.
The drier season lasts 8.0 months, from September 29 to May 28. The smallest chance of a wet day is 5% on April 7.
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 Ralph M Calhoun Memorial Airport changes throughout the year.
Snow alone is the most common for 6.0 months, from October 12 to April 13. The highest chance of a day with snow alone is 12% on January 3.
Rain alone is the most common for 6.0 months, from April 13 to October 12. The highest chance of a day with rain alone is 33% on August 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. Ralph M Calhoun Memorial Airport experiences significant seasonal variation in monthly rainfall.
The rainy period of the year lasts for 5.2 months, from May 5 to October 11, with a sliding 31-day rainfall of at least 0.5 inches. The most rain falls during the 31 days centered around August 10, with an average total accumulation of 2.3 inches.
The rainless period of the year lasts for 6.8 months, from October 11 to May 5. The least rain falls around December 14, with an average total accumulation of 0.0 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. Ralph M Calhoun Memorial Airport experiences some seasonal variation in monthly liquid-equivalent snowfall.
The snowy period of the year lasts for 7.1 months, from September 19 to April 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 30, with an average total liquid-equivalent accumulation of 0.6 inches.
The snowless period of the year lasts for 4.9 months, from April 22 to September 19. The least snow falls around July 13, with an average total liquid-equivalent accumulation of 0.0 inches.
Average Liquid-Equivalent Monthly Snowfall
The length of the day at Ralph M Calhoun Memorial Airport varies extremely over the course of the year. In 2017, the shortest day is December 21, with 3 hours, 27 minutes of daylight; the longest day is June 21, with 22 hours, 18 minutes of daylight.
Hours of Daylight and Twilight
The earliest sunrise is at 3:01 AM on June 20, and the latest sunrise is 8 hours, 22 minutes later at 11:23 AM on December 24. The earliest sunset is at 2:49 PM on December 18, and the latest sunset is 10 hours, 30 minutes later at 1:19 AM on June 20.
Daylight saving time (DST) is observed at Ralph M Calhoun Memorial Airport 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 at Ralph M Calhoun Memorial 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
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 Ralph M Calhoun Memorial Airport experiences mild seasonal variation over the course of the year.
The windier part of the year lasts for 5.2 months, from November 3 to April 8, with average wind speeds of more than 3.8 miles per hour. The windiest day of the year is January 9, with an average hourly wind speed of 5.2 miles per hour.
The calmer time of year lasts for 6.8 months, from April 8 to November 3. The calmest day of the year is July 8, with an average hourly wind speed of 2.6 miles per hour.
Average Wind Speed
The predominant average hourly wind direction at Ralph M Calhoun Memorial Airport varies throughout the year.
The wind is most often from the west for 2.8 months, from June 1 to August 25, with a peak percentage of 45% on July 6. The wind is most often from the east for 9.2 months, from August 25 to June 1, with a peak percentage of 72% 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 3.0 months, from April 28 to July 28, with an average daily incident shortwave energy per square meter above 4.6 kWh. The brightest day of the year is June 22, with an average of 5.7 kWh.
The darker period of the year lasts for 4.5 months, from October 11 to February 26, with an average daily incident shortwave energy per square meter below 1.2 kWh. The darkest day of the year is December 22, with an average of 0.0 kWh.
Average Daily Incident Shortwave Solar Energy
For the purposes of this report, the geographical coordinates of Ralph M Calhoun Memorial Airport are 65.174 deg latitude, -152.109 deg longitude, and 220 ft elevation.
The topography within 2 miles of Ralph M Calhoun Memorial Airport contains only modest variations in elevation, with a maximum elevation change of 292 feet and an average elevation above sea level of 243 feet. Within 10 miles contains only modest variations in elevation (1,982 feet). Within 50 miles contains large variations in elevation (5,341 feet).
The area within 2 miles of Ralph M Calhoun Memorial Airport is covered by trees (44%), sparse vegetation (20%), and water (18%), within 10 miles by trees (82%), and within 50 miles by trees (52%) and shrubs (39%).
This report illustrates the typical weather at Ralph M Calhoun Memorial 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
Ralph M Calhoun Memorial 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.
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.