Average Weather in Gilly-sur-Isère France
In Gilly-sur-Isère, the summers are warm, 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 27°F to 79°F and is rarely below 19°F or above 88°F.
Based on the tourism score, the best time of year to visit Gilly-sur-Isère for warm-weather activities is from late June to early September.
The warm season lasts for 3.2 months, from June 4 to September 11, with an average daily high temperature above 71°F. The hottest day of the year is August 4, with an average high of 79°F and low of 58°F.
The cold season lasts for 3.5 months, from November 19 to March 3, with an average daily high temperature below 48°F. The coldest day of the year is January 12, with an average low of 27°F and high of 40°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 Gilly-sur-Isère, 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 Gilly-sur-Isère begins around June 19 and lasts for 3.0 months, ending around September 17. On July 22, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 68% of the time, and overcast or mostly cloudy 32% of the time.
The cloudier part of the year begins around September 17 and lasts for 9.0 months, ending around June 19. On May 8, 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
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 Gilly-sur-Isère varies throughout the year.
The wetter season lasts 8.8 months, from April 5 to December 31, with a greater than 31% chance of a given day being a wet day. The chance of a wet day peaks at 39% on May 25.
The drier season lasts 3.2 months, from December 31 to April 5. The smallest chance of a wet day is 23% on March 5.
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 39% 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. Gilly-sur-Isère experiences some seasonal variation in monthly rainfall.
Rain falls throughout the year in Gilly-sur-Isère. The most rain falls during the 31 days centered around May 27, with an average total accumulation of 3.1 inches.
The least rain falls around March 9, with an average total accumulation of 2.3 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. Gilly-sur-Isère experiences some seasonal variation in monthly liquid-equivalent snowfall.
The snowy period of the year lasts for 3.0 months, from November 23 to February 23, with a sliding 31-day liquid-equivalent snowfall of at least 0.1 inches. The most snow falls during the 31 days centered around December 30, with an average total liquid-equivalent accumulation of 0.3 inches.
The snowless period of the year lasts for 9.0 months, from February 23 to November 23. The least snow falls around July 18, with an average total liquid-equivalent accumulation of 0.0 inches.
Average Liquid-Equivalent Monthly Snowfall
The length of the day in Gilly-sur-Isère varies significantly over the course of the year. In 2019, the shortest day is December 22, with 8 hours, 41 minutes of daylight; the longest day is June 21, with 15 hours, 42 minutes of daylight.
Hours of Daylight and Twilight
The earliest sunrise is at 5:44 AM on June 16, and the latest sunrise is 2 hours, 31 minutes later at 8:15 AM on January 2. The earliest sunset is at 4:50 PM on December 11, and the latest sunset is 4 hours, 38 minutes later at 9:28 PM on June 26.
Daylight saving time (DST) is observed in Gilly-sur-Isère during 2019, starting in the spring on March 31, lasting 6.9 months, and ending in the fall on October 27.
Sunrise & Sunset with Twilight and Daylight Saving Time
The perceived humidity level in Gilly-sur-Isère, 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
dry 55°F comfortable 60°F humid 65°F muggy 70°F oppressive 75°F miserable
Average Wind Speed
The predominant average hourly wind direction in Gilly-sur-Isère varies throughout the year.
The wind is most often from the east for 4.3 weeks, from January 14 to February 13 and for 1.3 weeks, from February 24 to March 5, with a peak percentage of 38% on January 22. The wind is most often from the south for 1.6 weeks, from February 13 to February 24; for 3.9 weeks, from March 5 to April 1; and for 3.9 months, from September 18 to January 14, with a peak percentage of 34% on February 16. The wind is most often from the west for 4.7 months, from April 28 to September 18, with a peak percentage of 40% on June 26.
Best Time of Year to Visit
To characterize how pleasant the weather is in Gilly-sur-Isère 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 Gilly-sur-Isère 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 Gilly-sur-Isère for hot-weather activities is from early 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 Gilly-sur-Isère typically lasts for 7.0 months (213 days), from around April 6 to around November 5, rarely starting before March 16 or after April 26, and rarely ending before October 16 or after November 26.
Time Spent in Various Temperature Bands and the Growing Season
Based on growing degree days alone, the first spring blooms in Gilly-sur-Isère should appear around April 19, only rarely appearing before April 5 or after May 4.
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 11 to August 18, with an average daily incident shortwave energy per square meter above 6.1 kWh. The brightest day of the year is July 6, with an average of 7.2 kWh.
The darker period of the year lasts for 3.4 months, from October 28 to February 10, with an average daily incident shortwave energy per square meter below 2.6 kWh. The darkest day of the year is December 23, with an average of 1.5 kWh.
Average Daily Incident Shortwave Solar Energy
For the purposes of this report, the geographical coordinates of Gilly-sur-Isère are 45.659 deg latitude, 6.351 deg longitude, and 1,654 ft elevation.
The topography within 2 miles of Gilly-sur-Isère contains large variations in elevation, with a maximum elevation change of 2,008 feet and an average elevation above sea level of 1,368 feet. Within 10 miles contains large variations in elevation (7,795 feet). Within 50 miles also contains extreme variations in elevation (15,115 feet).
The area within 2 miles of Gilly-sur-Isère is covered by cropland (42%), artificial surfaces (32%), and trees (19%), within 10 miles by trees (60%) and grassland (16%), and within 50 miles by trees (38%) and grassland (21%).
This report illustrates the typical weather in Gilly-sur-Isère, 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 3 weather stations near enough to contribute to our estimation of the temperature and dew point in Gilly-sur-Isère.
For each station, the records are corrected for the elevation difference between that station and Gilly-sur-Isère 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 Gilly-sur-Isère is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Gilly-sur-Isère and a given station.
Time zones for aiports and weather stations are provided by AskGeo.com .