Average Weather in Stonington Maine, United States
In Stonington, the summers are comfortable; the winters are freezing, wet, and windy; and it is partly cloudy year round. Over the course of the year, the temperature typically varies from 17°F to 72°F and is rarely below 3°F or above 79°F.
Based on the tourism score, the best time of year to visit Stonington for warm-weather activities is from early July to early September.
The warm season lasts for 3.3 months, from June 9 to September 19, with an average daily high temperature above 64°F. The hottest day of the year is July 26, with an average high of 72°F and low of 59°F.
The cold season lasts for 3.3 months, from December 8 to March 17, with an average daily high temperature below 40°F. The coldest day of the year is January 29, with an average low of 17°F and high of 32°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 Stonington, 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 Stonington begins around June 26 and lasts for 4.4 months, ending around November 7. On September 3, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 63% of the time, and overcast or mostly cloudy 37% of the time.
The cloudier part of the year begins around November 7 and lasts for 7.6 months, ending around June 26. On May 16, the cloudiest day of the year, the sky is overcast or mostly cloudy 58% of the time, and clear, mostly clear, or partly cloudy 42% 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 in Stonington varies throughout the year.
The wetter season lasts 9.5 months, from October 16 to August 1, with a greater than 27% chance of a given day being a wet day. The chance of a wet day peaks at 33% on December 11.
The drier season lasts 2.5 months, from August 1 to October 16. The smallest chance of a wet day is 22% on August 30.
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 throughout the year is rain alone, with a peak probability of 31% on June 14.
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. Stonington experiences significant seasonal variation in monthly rainfall.
Rain falls throughout the year in Stonington. The most rain falls during the 31 days centered around November 6, with an average total accumulation of 4.5 inches.
The least rain falls around January 30, with an average total accumulation of 2.1 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. Stonington experiences significant seasonal variation in monthly liquid-equivalent snowfall.
The snowy period of the year lasts for 5.3 months, from November 8 to April 19, with a sliding 31-day liquid-equivalent snowfall of at least 0.1 inches. The most snow falls during the 31 days centered around January 24, with an average total liquid-equivalent accumulation of 1.1 inches.
The snowless period of the year lasts for 6.7 months, from April 19 to November 8. The least snow falls around July 21, with an average total liquid-equivalent accumulation of 0.0 inches.
Average Liquid-Equivalent Monthly Snowfall
The length of the day in Stonington varies significantly over the course of the year. In 2021, the shortest day is December 21, with 8 hours, 52 minutes of daylight; the longest day is June 20, with 15 hours, 30 minutes of daylight.
Hours of Daylight and Twilight
The earliest sunrise is at 4:50 AM on June 14, and the latest sunrise is 2 hours, 28 minutes later at 7:18 AM on November 6. The earliest sunset is at 3:55 PM on December 9, and the latest sunset is 4 hours, 26 minutes later at 8:22 PM on June 26.
Daylight saving time (DST) is observed in Stonington during 2021, starting in the spring on March 14, lasting 7.8 months, and ending in the fall on November 7.
Sunrise & Sunset with Twilight and Daylight Saving Time
The figure below presents a compact representation of key lunar data for 2021. 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.
Moon Rise, Set & Phases
The perceived humidity level in Stonington, 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, staying within 5% of 5% throughout.
Humidity Comfort Levels
dry 55°F comfortable 60°F humid 65°F muggy 70°F oppressive 75°F miserable
The average hourly wind speed in Stonington experiences significant seasonal variation over the course of the year.
The windier part of the year lasts for 6.2 months, from October 11 to April 18, with average wind speeds of more than 10.3 miles per hour. The windiest day of the year is January 13, with an average hourly wind speed of 13.6 miles per hour.
The calmer time of year lasts for 5.8 months, from April 18 to October 11. The calmest day of the year is August 8, with an average hourly wind speed of 6.9 miles per hour.
Average Wind Speed
The predominant average hourly wind direction in Stonington varies throughout the year.
The wind is most often from the north for 2.3 months, from February 8 to April 16, with a peak percentage of 38% on February 12. The wind is most often from the south for 5.7 months, from April 16 to October 6, with a peak percentage of 43% on July 14. The wind is most often from the west for 4.1 months, from October 6 to February 8, with a peak percentage of 42% on January 1.
Stonington 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 significant seasonal variation over the course of the year.
The time of year with warmer water lasts for 3.1 months, from July 3 to October 6, with an average temperature above 54°F. The day of the year with the warmest water is August 14, with an average temperature of 58°F.
The time of year with cooler water lasts for 3.4 months, from January 13 to April 27, with an average temperature below 41°F. The day of the year with the coolest water is March 12, with an average temperature of 37°F.
Average Water Temperature
Best Time of Year to Visit
To characterize how pleasant the weather is in Stonington 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 Stonington for general outdoor tourist activities is from early July to early September, with a peak score in the second week of August.
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 Stonington for hot-weather activities is from mid July to mid August, with a peak score in the last 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.
The growing season in Stonington typically lasts for 6.0 months (182 days), from around April 25 to around October 24, rarely starting before April 8 or after May 10, and rarely ending before October 5 or after November 11.
Time Spent in Various Temperature Bands and the Growing Season
Based on growing degree days alone, the first spring blooms in Stonington should appear around May 27, only rarely appearing before May 19 or after June 5.
Growing Degree Days
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 3.4 months, from May 10 to August 23, with an average daily incident shortwave energy per square meter above 5.7 kWh. The brightest day of the year is July 1, with an average of 6.8 kWh.
The darker period of the year lasts for 3.4 months, from November 1 to February 12, with an average daily incident shortwave energy per square meter below 2.5 kWh. The darkest day of the year is December 24, with an average of 1.4 kWh.
Average Daily Incident Shortwave Solar Energy
For the purposes of this report, the geographical coordinates of Stonington are 44.156 deg latitude, -68.667 deg longitude, and 56 ft elevation.
The topography within 2 miles of Stonington contains only modest variations in elevation, with a maximum elevation change of 151 feet and an average elevation above sea level of 25 feet. Within 10 miles contains only modest variations in elevation (518 feet). Within 50 miles contains significant variations in elevation (1,532 feet).
The area within 2 miles of Stonington is covered by water (60%) and trees (25%), within 10 miles by water (81%) and trees (15%), and within 50 miles by water (61%) and trees (35%).
This report illustrates the typical weather in Stonington, 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 are 2 weather stations near enough to contribute to our estimation of the temperature and dew point in Stonington.
For each station, the records are corrected for the elevation difference between that station and Stonington according to the International Standard Atmosphere , and by the relative change present in the MERRA-2 satellite-era reanalysis between the two locations.
The estimated value at Stonington is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Stonington and a given station.
Time zones for airports and weather stations are provided by AskGeo.com .