Average Weather at Northway Airport Alaska, United States

At Northway Airport, the summers are long and comfortable, the winters are frigid and snowy, and it is mostly cloudy year round. Over the course of the year, the temperature typically varies from -19°F to 70°F and is rarely below -47°F or above 79°F.

The warm season lasts for 4.1 months, from May 9 to September 12, with an average daily high temperature above 55°F. The hottest day of the year is July 7, with an average high of 70°F and low of 49°F.

The cold season lasts for 3.5 months, from November 10 to February 23, with an average daily high temperature below 12°F. The coldest day of the year is January 14, with an average low of -19°F and high of -3°F.

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

The average hourly temperature, color coded into bands: frigid < 15°F < freezing < 32°F < chilly < 45°F < cold < 55°F < cool < 65°F < comfortable < 75°F < warm < 85°F < hot < 95°F < sweltering. The shaded overlays indicate night and civil twilight.

Clouds

At Northway 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 Northway Airport begins around April 22 and lasts for 4.8 months, ending around September 15. On May 27, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 45% of the time, and overcast or mostly cloudy 55% of the time.

The cloudier part of the year begins around September 15 and lasts for 7.2 months, ending around April 22. On December 6, 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.

Cloud Cover

The percentage of time spent in each cloud cover band, categorized by the percentage of the sky covered by clouds: clear < 20% < mostly clear < 40% < partly cloudy < 60% < mostly cloudy < 80% < overcast.

Precipitation

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

The wetter season lasts 4.9 months, from May 22 to October 18, with a greater than 17% chance of a given day being a wet day. The chance of a wet day peaks at 29% on July 16.

The drier season lasts 7.1 months, from October 18 to May 22. The smallest chance of a wet day is 4% on March 29.

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 Northway Airport changes throughout the year.

Snow alone is the most common for 6.1 months, from October 6 to April 11. The highest chance of a day with snow alone is 12% on October 25.

Rain alone is the most common for 5.8 months, from April 11 to October 6. The highest chance of a day with rain alone is 29% on July 16.

Daily Chance of Precipitation

The percentage of days in which various types of precipitation are observed, excluding trace quantities: rain alone, snow alone, and mixed (both rain and snow fell in the same day).

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. Northway Airport experiences significant seasonal variation in monthly rainfall.

The rainy period of the year lasts for 5.1 months, from May 1 to October 5, with a sliding 31-day rainfall of at least 0.5 inches. The most rain falls during the 31 days centered around July 7, with an average total accumulation of 2.4 inches.

The rainless period of the year lasts for 6.9 months, from October 5 to May 1. The least rain falls around December 17, with an average total accumulation of 0.0 inches.

Average Monthly Rainfall

The average rainfall (solid line) accumulated over the course of a sliding 31-day period centered on the day in question, with 25th to 75th and 10th to 90th percentile bands. The thin dotted line is the corresponding average liquid-equivalent snowfall.

Snowfall

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. Northway Airport experiences some seasonal variation in monthly liquid-equivalent snowfall.

The snowy period of the year lasts for 7.7 months, from September 9 to April 30, with a sliding 31-day liquid-equivalent snowfall of at least 0.1 inches. The most snow falls during the 31 days centered around October 23, with an average total liquid-equivalent accumulation of 0.5 inches.

The snowless period of the year lasts for 4.3 months, from April 30 to September 9. The least snow falls around July 11, with an average total liquid-equivalent accumulation of 0.0 inches.

Average Liquid-Equivalent Monthly Snowfall

The average liquid-equivalent snowfall (solid line) accumulated over the course of a sliding 31-day period centered on the day in question, with 25th to 75th and 10th to 90th percentile bands. The thin dotted line is the corresponding average rainfall.

Sun

The length of the day at Northway Airport varies extremely over the course of the year. In 2017, the shortest day is December 21, with 4 hours, 44 minutes of daylight; the longest day is June 21, with 20 hours, 18 minutes of daylight.

Hours of Daylight and Twilight

The number of hours during which the Sun is visible (black line). From bottom (most yellow) to top (most gray), the color bands indicate: full daylight, twilight (civil, nautical, and astronomical), and full night.

The earliest sunrise is at 3:20 AM on June 19, and the latest sunrise is 6 hours, 45 minutes later at 10:05 AM on December 25. The earliest sunset is at 2:46 PM on December 17, and the latest sunset is 8 hours, 52 minutes later at 11:38 PM on June 21.

Daylight saving time (DST) is observed at Northway 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

The solar day over the course of the year 2017. From bottom to top, the black lines are the previous solar midnight, sunrise, solar noon, sunset, and the next solar midnight. The day, twilights (civil, nautical, and astronomical), and night are indicated by the color bands from yellow to gray. The transitions to and from daylight saving time are indicated by the 'DST' labels.

Humidity

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 Northway 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

The percentage of time spent at various humidity comfort levels, categorized by dew point: dry < 55°F < comfortable < 60°F < humid < 65°F < muggy < 70°F < oppressive < 75°F < miserable.

Wind

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 Northway Airport does not vary significantly over the course of the year, remaining within 0.2 miles per hour of 2.1 miles per hour throughout.

Average Wind Speed

The average of mean hourly wind speeds (dark gray line), with 25th to 75th and 10th to 90th percentile bands.

The predominant average hourly wind direction at Northway Airport varies throughout the year.

The wind is most often from the west for 5.0 months, from April 18 to September 18, with a peak percentage of 64% on July 22. The wind is most often from the south for 5.0 days, from September 18 to September 23, with a peak percentage of 29% on September 22. The wind is most often from the east for 6.8 months, from September 23 to April 18, with a peak percentage of 36% on January 1.

Wind Direction

The percentage of hours in which the mean wind direction is from each of the four cardinal wind directions (north, east, south, and west), excluding hours in which the mean wind speed is less than 1 mph. The lightly tinted areas at the boundaries are the percentage of hours spent in the implied intermediate directions (northeast, southeast, southwest, and northwest).

Solar Energy

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 3.3 months, from April 28 to August 7, with an average daily incident shortwave energy per square meter above 4.7 kWh. The brightest day of the year is June 12, with an average of 5.9 kWh.

The darker period of the year lasts for 4.3 months, from October 15 to February 23, with an average daily incident shortwave energy per square meter below 1.3 kWh. The darkest day of the year is December 22, with an average of 0.1 kWh.

Average Daily Incident Shortwave Solar Energy

The average daily shortwave solar energy reaching the ground per square meter (orange line), with 25th to 75th and 10th to 90th percentile bands.

Topography

For the purposes of this report, the geographical coordinates of Northway Airport are 62.961 deg latitude, -141.929 deg longitude, and 1,703 ft elevation.

The topography within 2 miles of Northway Airport contains only modest variations in elevation, with a maximum elevation change of 125 feet and an average elevation above sea level of 1,716 feet. Within 10 miles contains only modest variations in elevation (1,932 feet). Within 50 miles contains very significant variations in elevation (7,999 feet).

The area within 2 miles of Northway Airport is covered by trees (82%), within 10 miles by trees (63%) and herbaceous vegetation (23%), and within 50 miles by trees (59%) and shrubs (23%).

Data Sources

This report illustrates the typical weather at Northway 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

Northway 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.

There are no other weather stations in our network within 200 kilometers of this location. Consequently, in the case of missing or erroneous measurements from this station, we fall back on NASA's MERRA-2 modern-era reanalysis , adjusted according to typical seasonal and diurnal differences between this station and the wide-area MERRA-2 reconstructed values.

Other Data

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.