Climate and Average Weather Year Round in Prudhoe Bay Alaska, United States

In Prudhoe Bay, the summers are cold; the winters are long, frigid, snowy, and windy; and it is overcast year round. Over the course of the year, the temperature typically varies from -21°F to 54°F and is rarely below -40°F or above 67°F.

Based on the tourism score, the best time of year to visit Prudhoe Bay for warm-weather activities is from early July to early August.

The warm season lasts for 3.0 months, from June 8 to September 8, with an average daily high temperature above 41°F. The hottest month of the year in Prudhoe Bay is July, with an average high of 53°F and low of 40°F.

The cold season lasts for 4.6 months, from November 18 to April 6, with an average daily high temperature below 4°F. The coldest month of the year in Prudhoe Bay is February, with an average low of -20°F and high of -8°F.

In Prudhoe Bay, the average percentage of the sky covered by clouds experiences significant seasonal variation over the course of the year.

The clearer part of the year in Prudhoe Bay begins around April 30 and lasts for 5.5 months, ending around October 16.

The clearest month of the year in Prudhoe Bay is June, during which on average the sky is clear, mostly clear, or partly cloudy 33% of the time.

The cloudier part of the year begins around October 16 and lasts for 6.5 months, ending around April 30.

The cloudiest month of the year in Prudhoe Bay is January, during which on average the sky is overcast or mostly cloudy 89% 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 in Prudhoe Bay varies throughout the year.

The wetter season lasts 3.1 months, from June 22 to September 26, with a greater than 12% chance of a given day being a wet day. The month with the most wet days in Prudhoe Bay is August, with an average of 6.5 days with at least 0.04 inches of precipitation.

The drier season lasts 8.9 months, from September 26 to June 22. The month with the fewest wet days in Prudhoe Bay is March, with an average of 0.7 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 in Prudhoe Bay changes throughout the year.

Snow alone is the most common for 7.9 months, from September 25 to May 23. The month with the most days of snow alone in Prudhoe Bay is October, with an average of 1.3 days.

Rain alone is the most common for 4.1 months, from May 23 to September 25. The month with the most days of rain alone in Prudhoe Bay is August, with an average of 6.3 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. Prudhoe Bay experiences some seasonal variation in monthly rainfall.

The rainy period of the year lasts for 3.1 months, from June 12 to September 17, with a sliding 31-day rainfall of at least 0.5 inches. The month with the most rain in Prudhoe Bay is August, with an average rainfall of 1.2 inches.

The rainless period of the year lasts for 8.9 months, from September 17 to June 12. The month with the least rain in Prudhoe Bay is March, with an average rainfall of 0.0 inches.

Snowfall

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

The snowy period of the year lasts for 9.2 months, from September 2 to June 10, with a sliding 31-day snowfall of at least 1.0 inches. The month with the most snow in Prudhoe Bay is October, with an average snowfall of 1.9 inches.

The snowless period of the year lasts for 2.8 months, from June 10 to September 2. The least snow falls around July 13, with an average total accumulation of 0.0 inches.

Due to its extreme latitude, Prudhoe Bay experiences polar day (also known as the midnight Sun) during the summer and polar night during the winter. These are periods of time in which the sun is continuously above or below the horizon for more than one day. The precise start and end dates of polar day and night vary from year to year and depend on the precise location and elevation of the observer, and the local topography.

In the summer in Prudhoe Bay during 2024, the Sun is continuously above the horizon for 2.4 months, rising at 2:13 AM on May 14, and not setting again until 1:38 AM on July 28.

In the winter in Prudhoe Bay during 2024, the Sun is continuously below the horizon for 1.9 months, setting at 1:12 PM on November 22, and not rising again until 12:45 PM on January 18.

Daylight saving time (DST) is observed in Prudhoe Bay during 2024, starting in the spring on March 10, lasting 7.8 months, and ending in the fall on November 3.

The figure below presents a compact representation of key lunar data for 2024. 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 in Prudhoe Bay, 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 in Prudhoe Bay experiences significant seasonal variation over the course of the year.

The windier part of the year lasts for 7.9 months, from September 16 to May 13, with average wind speeds of more than 11.1 miles per hour. The windiest month of the year in Prudhoe Bay is January, with an average hourly wind speed of 12.6 miles per hour.

The calmer time of year lasts for 4.1 months, from May 13 to September 16. The calmest month of the year in Prudhoe Bay is July, with an average hourly wind speed of 9.5 miles per hour.

The predominant average hourly wind direction in Prudhoe Bay is from the east throughout the year.

Prudhoe Bay is located near a large body of water (e.g., ocean, sea, or large lake). This section reports on the wide-area average surface temperature of that water.

The average water temperature experiences some seasonal variation over the course of the year.

The time of year with warmer water lasts for 1.7 months, from July 21 to September 10, with an average temperature above 34°F. The month of the year in Prudhoe Bay with the warmest water is August, with an average temperature of 36°F.

The time of year with cooler water lasts for 7.5 months, from October 21 to June 7, with an average temperature below 30°F. The month of the year in Prudhoe Bay with the coolest water is February, with an average temperature of 29°F.

To characterize how pleasant the weather is in Prudhoe Bay 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 Prudhoe Bay for general outdoor tourist activities is from early July to early August, with a peak score in the last 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 Prudhoe Bay for hot-weather activities is from mid to late 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 in Prudhoe Bay typically lasts for 1.7 months (51 days), from around June 27 to around August 17, rarely starting before June 6, or ending after September 7.

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.

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 5 to July 20, with an average daily incident shortwave energy per square meter above 4.7 kWh. The brightest month of the year in Prudhoe Bay is June, with an average of 5.8 kWh.

The darker period of the year lasts for 5.5 months, from September 27 to March 11, with an average daily incident shortwave energy per square meter below 1.2 kWh. The darkest month of the year in Prudhoe Bay is December, with an average of 0.0 kWh.

For the purposes of this report, the geographical coordinates of Prudhoe Bay are 70.255 deg latitude, -148.337 deg longitude, and 46 ft elevation.

The topography within 2 miles of Prudhoe Bay is essentially flat, with a maximum elevation change of 59 feet and an average elevation above sea level of 39 feet. Within 10 miles is also essentially flat (82 feet). Within 50 miles is essentially flat (965 feet).

The area within 2 miles of Prudhoe Bay is covered by sparse vegetation (56%), herbaceous vegetation (21%), and water (13%), within 10 miles by sparse vegetation (31%) and water (28%), and within 50 miles by water (45%) and grassland (33%).