Climate and Average Weather Year Round in Nynäshamn Sweden

In Nynäshamn, the summers are short, comfortable, and partly cloudy and the winters are long, freezing, snowy, windy, and mostly cloudy. Over the course of the year, the temperature typically varies from 24°F to 69°F and is rarely below 9°F or above 77°F.

Based on the tourism score, the best time of year to visit Nynäshamn for warm-weather activities is from late June to mid August.

The warm season lasts for 2.9 months, from June 9 to September 5, with an average daily high temperature above 62°F. The hottest month of the year in Nynäshamn is July, with an average high of 69°F and low of 54°F.

The cold season lasts for 4.0 months, from November 21 to March 23, with an average daily high temperature below 40°F. The coldest month of the year in Nynäshamn is February, with an average low of 24°F and high of 33°F.

In Nynäshamn, 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 Nynäshamn begins around April 21 and lasts for 5.6 months, ending around October 9.

The clearest month of the year in Nynäshamn is July, 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 October 9 and lasts for 6.4 months, ending around April 21.

The cloudiest month of the year in Nynäshamn is January, during which on average the sky is overcast or mostly cloudy 72% 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 Nynäshamn varies throughout the year.

The wetter season lasts 6.7 months, from June 12 to January 2, with a greater than 24% chance of a given day being a wet day. The month with the most wet days in Nynäshamn is November, with an average of 8.7 days with at least 0.04 inches of precipitation.

The drier season lasts 5.3 months, from January 2 to June 12. The month with the fewest wet days in Nynäshamn is March, with an average of 5.5 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. The month with the most days of rain alone in Nynäshamn is November, with an average of 8.1 days. Based on this categorization, the most common form of precipitation throughout the year is rain alone, with a peak probability of 29% on November 12.

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. Nynäshamn experiences some seasonal variation in monthly rainfall.

Rain falls throughout the year in Nynäshamn. The month with the most rain in Nynäshamn is July, with an average rainfall of 2.1 inches.

The month with the least rain in Nynäshamn is February, with an average rainfall of 0.6 inches.

Snowfall

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

The snowy period of the year lasts for 4.5 months, from November 19 to April 2, with a sliding 31-day snowfall of at least 1.0 inches. The month with the most snow in Nynäshamn is February, with an average snowfall of 2.7 inches.

The snowless period of the year lasts for 7.5 months, from April 2 to November 19. The least snow falls around August 5, with an average total accumulation of 0.0 inches.

The length of the day in Nynäshamn varies extremely over the course of the year. In 2024, the shortest day is December 21, with 6 hours, 12 minutes of daylight; the longest day is June 20, with 18 hours, 28 minutes of daylight.

The earliest sunrise is at 3:35 AM on June 18, and the latest sunrise is 5 hours, 6 minutes later at 8:41 AM on December 27. The earliest sunset is at 2:51 PM on December 15, and the latest sunset is 7 hours, 13 minutes later at 10:04 PM on June 23.

Daylight saving time (DST) is observed in Nynäshamn during 2024, starting in the spring on March 31, lasting 6.9 months, and ending in the fall on October 27.

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 Nynäshamn, 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 1% of 1% 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 Nynäshamn experiences significant seasonal variation over the course of the year.

The windier part of the year lasts for 6.3 months, from September 8 to March 17, with average wind speeds of more than 9.5 miles per hour. The windiest month of the year in Nynäshamn is January, with an average hourly wind speed of 11.3 miles per hour.

The calmer time of year lasts for 5.7 months, from March 17 to September 8. The calmest month of the year in Nynäshamn is June, with an average hourly wind speed of 7.5 miles per hour.

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

The wind is most often from the south for 3.0 months, from April 5 to July 6 and for 1.3 weeks, from August 2 to August 11, with a peak percentage of 34% on July 1. The wind is most often from the west for 3.9 weeks, from July 6 to August 2 and for 7.8 months, from August 11 to April 5, with a peak percentage of 34% on July 21.

Nynäshamn 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 2.5 months, from June 29 to September 14, with an average temperature above 57°F. The month of the year in Nynäshamn with the warmest water is August, with an average temperature of 62°F.

The time of year with cooler water lasts for 4.5 months, from December 15 to May 1, with an average temperature below 40°F. The month of the year in Nynäshamn with the coolest water is March, with an average temperature of 35°F.

To characterize how pleasant the weather is in Nynäshamn 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 Nynäshamn for general outdoor tourist activities is from late June to mid August, with a peak score in the third 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 Nynäshamn for hot-weather activities is from mid July to early August, with a peak score in the third 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 Nynäshamn typically lasts for 5.3 months (161 days), from around May 4 to around October 12, rarely starting before April 17 or after May 21, and rarely ending before September 21 or after November 4.

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 Nynäshamn should appear around May 27, only rarely appearing before May 19 or after June 7.

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 3.1 months, from May 4 to August 9, with an average daily incident shortwave energy per square meter above 5.1 kWh. The brightest month of the year in Nynäshamn is June, with an average of 6.2 kWh.

The darker period of the year lasts for 4.4 months, from October 16 to February 26, with an average daily incident shortwave energy per square meter below 1.4 kWh. The darkest month of the year in Nynäshamn is December, with an average of 0.2 kWh.

For the purposes of this report, the geographical coordinates of Nynäshamn are 58.903 deg latitude, 17.948 deg longitude, and 69 ft elevation.

The topography within 2 miles of Nynäshamn contains only modest variations in elevation, with a maximum elevation change of 220 feet and an average elevation above sea level of 47 feet. Within 10 miles also contains only modest variations in elevation (305 feet). Within 50 miles also contains only modest variations in elevation (413 feet).

The area within 2 miles of Nynäshamn is covered by water (48%), trees (25%), and artificial surfaces (23%), within 10 miles by water (61%) and trees (28%), and within 50 miles by water (64%) and trees (22%).