Average Weather in Trélex Switzerland
In Trélex, the summers are comfortable, the winters are very cold and wet, and it is partly cloudy year round. Over the course of the year, the temperature typically varies from 29°F to 78°F and is rarely below 20°F or above 88°F.
Based on the tourism score, the best time of year to visit Trélex for warm-weather activities is from late June to early September.
The warm season lasts for 3.1 months, from June 7 to September 9, with an average daily high temperature above 70°F. The hottest day of the year is August 4, with an average high of 78°F and low of 58°F.
The cold season lasts for 3.6 months, from November 17 to March 3, with an average daily high temperature below 46°F. The coldest day of the year is January 15, with an average low of 29°F and high of 38°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 Trélex, 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 Trélex begins around June 16 and lasts for 3.1 months, ending around September 18. On July 23, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 67% of the time, and overcast or mostly cloudy 33% of the time.
The cloudier part of the year begins around September 18 and lasts for 8.9 months, ending around June 16. On November 24, the cloudiest day of the year, the sky is overcast or mostly cloudy 59% of the time, and clear, mostly clear, or partly cloudy 41% of the time.
Cloud Cover Categories
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. The chance of wet days in Trélex varies throughout the year.
The wetter season lasts 7.9 months, from April 27 to December 25, with a greater than 34% chance of a given day being a wet day. The chance of a wet day peaks at 42% on May 25.
The drier season lasts 4.1 months, from December 25 to April 27. The smallest chance of a wet day is 26% on March 3.
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 42% on May 25.
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. Trélex experiences some seasonal variation in monthly rainfall.
Rain falls throughout the year in Trélex. The most rain falls during the 31 days centered around May 30, with an average total accumulation of 3.7 inches.
The least rain falls around March 8, with an average total accumulation of 2.6 inches.
Average Monthly Rainfall
The sliding 31-day liquid-equivalent quantity of snowfall in Trélex does not vary significantly over the course of the year, staying within 0.1 inches of 0.1 inches throughout.
Average Liquid-Equivalent Monthly Snowfall
The length of the day in Trélex varies significantly over the course of the year. In 2018, the shortest day is December 21, with 8 hours, 35 minutes of daylight; the longest day is June 21, with 15 hours, 49 minutes of daylight.
Hours of Daylight and Twilight
The earliest sunrise is at 5:42 AM on June 16, and the latest sunrise is 2 hours, 37 minutes later at 8:18 AM on January 1. The earliest sunset is at 4:48 PM on December 11, and the latest sunset is 4 hours, 44 minutes later at 9:31 PM on June 26.
Daylight saving time (DST) is observed in Trélex during 2018, starting in the spring on March 25, lasting 7.1 months, and ending in the fall on October 28.
Sunrise & Sunset with Twilight and Daylight Saving Time
The perceived humidity level in Trélex, 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.
Humidity Comfort Levels
The average hourly wind speed in Trélex experiences mild seasonal variation over the course of the year.
The windier part of the year lasts for 3.9 months, from January 6 to May 2, with average wind speeds of more than 6.9 miles per hour. The windiest day of the year is April 3, with an average hourly wind speed of 7.7 miles per hour.
The calmer time of year lasts for 8.1 months, from May 2 to January 6. The calmest day of the year is August 10, with an average hourly wind speed of 6.2 miles per hour.
Average Wind Speed
The predominant average hourly wind direction in Trélex varies throughout the year.
The wind is most often from the north for 1.2 months, from April 2 to May 7 and for 1.7 weeks, from September 4 to September 16, with a peak percentage of 34% on April 19. The wind is most often from the west for 3.9 months, from May 7 to September 4, with a peak percentage of 37% on July 5. The wind is most often from the south for 6.5 months, from September 16 to April 2, with a peak percentage of 49% on January 1.
Best Time of Year to Visit
To characterize how pleasant the weather is in Trélex 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 Trélex 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 Trélex for hot-weather activities is from early July to mid August, with a peak score in the first week of August.
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 Trélex typically lasts for 7.1 months (216 days), from around April 4 to around November 6, rarely starting before March 12 or after April 25, and rarely ending before October 18 or after November 30.
Time Spent in Various Temperature Bands and the Growing Season
Based on growing degree days alone, the first spring blooms in Trélex should appear around April 21, only rarely appearing before April 6 or after May 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 3.2 months, from May 13 to August 19, with an average daily incident shortwave energy per square meter above 5.9 kWh. The brightest day of the year is July 6, with an average of 7.0 kWh.
The darker period of the year lasts for 3.5 months, from October 28 to February 14, with an average daily incident shortwave energy per square meter below 2.4 kWh. The darkest day of the year is December 24, with an average of 1.2 kWh.
Average Daily Incident Shortwave Solar Energy
For the purposes of this report, the geographical coordinates of Trélex are 46.415 deg latitude, 6.208 deg longitude, and 1,670 ft elevation.
The topography within 2 miles of Trélex contains very significant variations in elevation, with a maximum elevation change of 1,027 feet and an average elevation above sea level of 1,686 feet. Within 10 miles contains very significant variations in elevation (4,275 feet). Within 50 miles also contains extreme variations in elevation (13,392 feet).
The area within 2 miles of Trélex is covered by cropland (71%), trees (15%), and artificial surfaces (14%), within 10 miles by trees (38%) and cropland (22%), and within 50 miles by trees (42%) and cropland (23%).
This report illustrates the typical weather in Trélex, 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 6 weather stations near enough to contribute to our estimation of the temperature and dew point in Trélex.
For each station, the records are corrected for the elevation difference between that station and Trélex 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 Trélex is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Trélex and a given station.
The stations contributing to this reconstruction are: Aéroport Genève-Cointrin (63%, 21 kilometers, south); Neuchatel (8%, 86 kilometers, northeast); Les Eplatures (7%, 87 kilometers, northeast); Sion (8%, 88 kilometers, east); Dole–Jura Airport (7%, 91 kilometers, northwest); and Besançon – La Vèze Aerodrome (7%, 94 kilometers, north).
Time zones for aiports and weather stations are provided by AskGeo.com .