Climate and Average Weather Year Round in Summerside Canada

In Summerside, the summers are comfortable; the winters are freezing, snowy, and windy; and it is partly cloudy year round. Over the course of the year, the temperature typically varies from 11°F to 74°F and is rarely below -3°F or above 81°F.

Based on the tourism score, the best time of year to visit Summerside for warm-weather activities is from late June to early September.

The warm season lasts for 3.3 months, from June 9 to September 18, with an average daily high temperature above 65°F. The hottest month of the year in Summerside is July, with an average high of 73°F and low of 60°F.

The cold season lasts for 3.4 months, from December 7 to March 19, with an average daily high temperature below 35°F. The coldest month of the year in Summerside is January, with an average low of 13°F and high of 26°F.

In Summerside, 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 Summerside begins around June 14 and lasts for 4.8 months, ending around November 7.

The clearest month of the year in Summerside is September, during which on average the sky is clear, mostly clear, or partly cloudy 57% of the time.

The cloudier part of the year begins around November 7 and lasts for 7.2 months, ending around June 14.

The cloudiest month of the year in Summerside is February, during which on average the sky is overcast or mostly cloudy 66% of the time.

Summerside does not experience significant seasonal variation in the frequency of wet days (i.e., those with greater than 0.04 inches of liquid or liquid-equivalent precipitation). The frequency ranges from 25% to 33%, with an average value of 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 in Summerside changes throughout the year.

Rain alone is the most common for 9.1 months, from March 16 to December 18. The month with the most days of rain alone in Summerside is June, with an average of 9.5 days.

Snow alone is the most common for 2.9 months, from December 18 to March 16. The month with the most days of snow alone in Summerside is January, with an average of 4.5 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. Summerside experiences significant seasonal variation in monthly rainfall.

Rain falls throughout the year in Summerside. The month with the most rain in Summerside is October, with an average rainfall of 3.2 inches.

The month with the least rain in Summerside is February, with an average rainfall of 0.8 inches.

Snowfall

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

The snowy period of the year lasts for 6.0 months, from November 3 to May 5, with a sliding 31-day snowfall of at least 1.0 inches. The month with the most snow in Summerside is February, with an average snowfall of 15.7 inches.

The snowless period of the year lasts for 6.0 months, from May 5 to November 3. The least snow falls around August 9, with an average total accumulation of 0.0 inches.

The length of the day in Summerside varies significantly over the course of the year. In 2024, the shortest day is December 21, with 8 hours, 35 minutes of daylight; the longest day is June 20, with 15 hours, 49 minutes of daylight.

The earliest sunrise is at 5:22 AM on June 15, and the latest sunrise is 2 hours, 37 minutes later at 7:58 AM on November 2. The earliest sunset is at 4:28 PM on December 10, and the latest sunset is 4 hours, 44 minutes later at 9:11 PM on June 25.

Daylight saving time (DST) is observed in Summerside 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.

Summerside experiences some seasonal variation in the perceived humidity.

The muggier period of the year lasts for 2.7 months, from June 24 to September 13, during which time the comfort level is muggy, oppressive, or miserable at least 4% of the time. The month with the most muggy days in Summerside is August, with 4.1 days that are muggy or worse.

The least muggy day of the year is March 11, when muggy conditions are essentially unheard of.

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 Summerside experiences significant seasonal variation over the course of the year.

The windier part of the year lasts for 6.7 months, from September 24 to April 14, with average wind speeds of more than 11.7 miles per hour. The windiest month of the year in Summerside is December, with an average hourly wind speed of 13.9 miles per hour.

The calmer time of year lasts for 5.3 months, from April 14 to September 24. The calmest month of the year in Summerside is July, with an average hourly wind speed of 9.5 miles per hour.

The predominant average hourly wind direction in Summerside varies throughout the year.

The wind is most often from the north for 3.9 weeks, from April 6 to May 3, with a peak percentage of 31% on April 13. The wind is most often from the south for 3.4 months, from May 3 to August 16, with a peak percentage of 44% on July 14. The wind is most often from the west for 7.7 months, from August 16 to April 6, with a peak percentage of 52% on January 1.

Summerside 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 2.9 months, from July 2 to September 28, with an average temperature above 58°F. The month of the year in Summerside with the warmest water is August, with an average temperature of 64°F.

The time of year with cooler water lasts for 4.9 months, from December 8 to May 4, with an average temperature below 37°F. The month of the year in Summerside with the coolest water is February, with an average temperature of 31°F.

To characterize how pleasant the weather is in Summerside 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 Summerside for general outdoor tourist activities is from late June to early September, with a peak score in the first 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 Summerside for hot-weather activities is from mid July to mid August, with a peak score in the last week of 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 Summerside typically lasts for 5.7 months (175 days), from around May 4 to around October 25, rarely starting before April 17 or after May 20, and rarely ending before October 10 or after November 11.

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 in Summerside should appear around May 27, only rarely appearing before May 17 or after June 4.

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 3.4 months, from May 11 to August 22, with an average daily incident shortwave energy per square meter above 5.4 kWh. The brightest month of the year in Summerside is June, with an average of 6.3 kWh.

The darker period of the year lasts for 3.5 months, from October 28 to February 13, with an average daily incident shortwave energy per square meter below 2.2 kWh. The darkest month of the year in Summerside is December, with an average of 1.1 kWh.

For the purposes of this report, the geographical coordinates of Summerside are 46.396 deg latitude, -63.788 deg longitude, and 39 ft elevation.

The topography within 2 miles of Summerside contains only modest variations in elevation, with a maximum elevation change of 125 feet and an average elevation above sea level of 30 feet. Within 10 miles also contains only modest variations in elevation (200 feet). Within 50 miles contains only modest variations in elevation (607 feet).

The area within 2 miles of Summerside is covered by water (34%), cropland (33%), and artificial surfaces (21%), within 10 miles by water (43%) and cropland (37%), and within 50 miles by water (60%) and trees (26%).