Average Weather For Turku, Finland

Location

This report describes the typical weather at the Turku Airport (Turku, Finland) weather station over the course of an average year. It is based on the historical records from 1974 to 2012. Earlier records are either unavailable or unreliable.

Turku has a humid continental climate with warm summers and no dry season. The area within 25 mi of this station is covered by forests (65%), oceans and seas (20%), and croplands (12%).

Temperature

Over the course of a year, the temperature typically varies from 15°F to 71°F and is rarely below -5°F or above 80°F.

Daily High and Low Temperature

The daily average low (blue) and high (red) temperature with percentile bands (inner band from 25th to 75th percentile, outer band from 10th to 90th percentile).

The warm season lasts from May 28 to September 4 with an average daily high temperature above 62°F. The hottest day of the year is July 31, with an average high of 71°F and low of 55°F.

The cold season lasts from November 25 to March 18 with an average daily high temperature below 35°F. The coldest day of the year is February 14, with an average low of 15°F and high of 26°F.

Fraction of Time Spent in Various Temperature Bands

The average fraction of time spent in various temperature bands: frigid (below 15°F), freezing (15°F to 32°F), cold (32°F to 50°F), cool (50°F to 65°F), comfortable (65°F to 75°F), warm (75°F to 85°F), hot (85°F to 100°F) and sweltering (above 100°F).

Sun

The length of the day varies significantly over the course of the year. The shortest day is December 21 with 5:43 hours of daylight; the longest day is June 20 with 19:02 hours of daylight.

Daily Hours of Daylight and Twilight

The number of hours during which the Sun is visible (black line), with various degrees of daylight, twilight, and night, indicated by the color bands. From bottom (most yellow) to top (most gray): full daylight, solar twilight (Sun is visible but less than 6° from the horizon), civil twilight (Sun is not visible but is less than 6° below the horizon), nautical twilight (Sun is between 6° and 12° below the horizon), astronomical twilight (Sun is between 12° and 18° below the horizon), and full night.

The earliest sunrise is at 4:00am on June 14 and the latest sunset is at 11:05pm on June 27. The latest sunrise is at 9:41am on December 27 and the earliest sunset is at 3:18pm on December 15.

Daylight savings time (DST) is observed in this location during 2012, starting in the spring on March 25 and ending in the fall on October 28.

Daily Sunrise & Sunset with Twilight and Daylight Savings Time

The solar day over the course of the year 2012 . From bottom to top, the black lines are the previous solar midnight, sunrise, solar noon, sunset, and the next solar midnight. The day, twilights (solar, civil, nautical, and astronomical), and night are indicated by the color bands from yellow to gray. The transitions to and from daylight savings time are indicated by the "DST" labels.

Clouds

The median cloud cover ranges from 56% (partly cloudy) to 92% (mostly cloudy). The sky is cloudiest on December 24 and clearest on June 6. The clearer part of the year begins around April 10. The cloudier part of the year begins around September 18.

Median Cloud Cover

The median daily cloud cover (black line) with percentile bands (inner band from 40th to 60th percentile, outer band from 25th to 75th percentile).

On June 6, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 57% of the time, and overcast or mostly cloudy 30% of the time.

On December 24, the cloudiest day of the year, the sky is overcast, mostly cloudy, or partly cloudy 75% of the time, and clear or mostly clear 17% of the time.

Cloud Cover Types

The fraction of time spent in each of the five sky cover categories. From top (most blue) to bottom (most gray), the categories are clear, mostly clear, partly cloudy, mostly cloudy, and overcast. Pink indicates missing data. Outside of the United States clear skies are often reported ambiguously, leading them to be lumped in with the missing data.

Precipitation

The probability that precipitation will be observed at this location varies throughout the year. Precipitation is most likely around December 14, occurring in 83% of days. Precipitation is least likely around May 12, occurring in 47% of days.

Probability of Precipitation at Some Point in the Day

The fraction of days in which various types of precipitation are observed. If more than one type of precipitation is reported in a given day, the more severe precipitation is counted. For example, if light rain is observed in the same day as a thunderstorm, that day counts towards the thunderstorm totals. The order of severity is from the top down in this graph, with the most severe at the bottom.

Over the entire year, the most common forms of precipitation are moderate rain, moderate snow, light rain, and light snow.

Moderate rain is the most severe precipitation observed during 33% of those days with precipitation. It is most likely around September 23, when it is observed during 36% of all days.

Moderate snow is the most severe precipitation observed during 29% of those days with precipitation. It is most likely around January 5, when it is observed during 47% of all days.

Light rain is the most severe precipitation observed during 15% of those days with precipitation. It is most likely around May 28, when it is observed during 14% of all days.

Light snow is the most severe precipitation observed during 11% of those days with precipitation. It is most likely around January 21, when it is observed during 17% of all days.

Types of Precipitation Throughout the Year

Relative frequency of various types of precipitation over the course of a typical year.

During the warm season, which lasts from May 28 to September 4, there is a 53% average chance that precipitation will be observed at some point during a given day. When precipitation does occur it is most often in the form of moderate rain (54% of days with precipitation have at worst moderate rain), light rain (23%), and thunderstorms (18%).

During the cold season, which lasts from November 25 to March 18, there is a 77% average chance that precipitation will be observed at some point during a given day. When precipitation does occur it is most often in the form of moderate snow (54% of days with precipitation have at worst moderate snow), light snow (20%), moderate rain (11%), and heavy snow (6%).

Warm Season Precipitation

Cold Season Precipitation

Relative frequency of various types of precipitation during the warm and cold seasons respectively.

Snow

The likelihood of snow falling is highest around January 16, occurring in 69% of days. The season in which it is relatively likely for snow to fall spans from October 30 to April 18.

Probability of Snow Fall Being Reported in a Given Day

Probability that snow will be reported at least once in a given day. The season is defined as the period during which the probability is greater than one third the maximum probability.

During peak snow season, accumulation at this location on a given day is about as likely as not. The chances of there being snow on the ground are highest around January 25, occurring 55% of the time. The season in which snow is relatively likely to be on the ground spans from November 13 to April 9.

Chance of at Least Some Snow on the Ground

The probability that there is snow on the ground. The season is defined as the period during which the probability is greater than one third of the maximum probability.

The snow is typically at its deepest on March 21, with a median depth of 9.8"; the depth exceeds 19.8" only one year out of ten.

Snow Depth When there is Snow on the Ground

The median depth of snow during times when there is at least some snow on the ground, with percentile bands (inner band from 25th to 75th percentile, outer band from 10th to 90th percentile).

Humidity

The relative humidity typically ranges from 42% (comfortable) to 98% (very humid) over the course of the year, rarely dropping below 25% (dry) and reaching as high as 100% (very humid).

The air is driest around May 15, at which time the relative humidity drops below 51% (mildly humid) three days out of four; it is most humid around November 24, exceeding 98% (very humid) three days out of four.

Relative Humidity

The average daily high (blue) and low (brown) relative humidity with percentile bands (inner bands from 25th to 75th percentile, outer bands from 10th to 90th percentile).

Dew Point

Dew point is often a better measure of how comfortable a person will find the weather than relative humidity because it more directly relates to whether perspiration will evaporate from the skin, thereby cooling the body. Lower dew points feel drier and higher dew points feel more humid.

Over the course of a year, the dew point typically varies from 12°F (dry) to 58°F (comfortable) and is rarely below -8°F (dry) or above 64°F (mildy humid).

The time of the year between June 12 and September 15 is the most comfortable, with dew points that are neither too dry nor too muggy.

Dew Point

The daily average low (blue) and high (red) dew point with percentile bands (inner band from 25th to 75th percentile, outer band from 10th to 90th percentile).

Wind

Over the course of the year typical wind speeds vary from 1 mph to 13 mph (light air to moderate breeze), rarely exceeding 20 mph (fresh breeze).

The highest average wind speed of 8 mph (gentle breeze) occurs around November 29, at which time the average daily maximum wind speed is 13 mph (moderate breeze).

The lowest average wind speed of 6 mph (light breeze) occurs around August 5, at which time the average daily maximum wind speed is 12 mph (gentle breeze).

Wind Speed

The average daily minimum (red), maximum (green), and average (black) wind speed with percentile bands (inner band from 25th to 75th percentile, outer band from 10th to 90th percentile).
The wind is most often out of the south (16% of the time), south west (15% of the time), west (13% of the time), east (12% of the time), and south east (11% of the time).

Wind Directions Over the Entire Year

The fraction of time spent with the wind blowing from the various directions over the entire year. Values do not sum to 100% because the wind direction is undefined when the wind speed is zero.

Fraction of Time Spent with Various Wind Directions

The fraction of time spent with the wind blowing from the various directions on a daily basis. Stacked values do not always sum to 100% because the wind direction is undefined when the wind speed is zero.