Average Weather in December in San Juan del Río Mexico
Daily high temperatures decrease by 2°F, from 74°F to 72°F, rarely falling below 66°F or exceeding 79°F.
Daily low temperatures decrease by 3°F, from 45°F to 42°F, rarely falling below 36°F or exceeding 50°F.
For reference, on May 11, the hottest day of the year, temperatures in San Juan del Río typically range from 55°F to 83°F, while on January 7, the coldest day of the year, they range from 42°F to 72°F.
Average High and Low Temperature in December
The figure below shows you a compact characterization of the hourly average temperatures for the quarter of the year centered on December. The horizontal axis is the day, 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 December
The month of December in San Juan del Río experiences essentially constant cloud cover, with the percentage of time that the sky is overcast or mostly cloudy remaining about 46% throughout the month.
The clearest day of the month is December 1, with clear, mostly clear, or partly cloudy conditions 56% of the time.
For reference, on September 14, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 83%, while on February 27, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 65%.
Cloud Cover Categories in December
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. In San Juan del Río, the chance of a wet day over the course of December is essentially constant, remaining around 2% throughout.
For reference, the year's highest daily chance of a wet day is 60% on July 14, and its lowest chance is 2% on December 13.
Probability of Precipitation in December
The average sliding 31-day rainfall during December in San Juan del Río is essentially constant, remaining about 0.1 inches throughout, and rarely exceeding 0.5 inches.
The lowest average 31-day accumulation is 0.1 inches on December 12.
Average Monthly Rainfall in December
Over the course of December in San Juan del Río, the length of the day is essentially constant. The shortest day of the month is December 21, with 10 hours, 54 minutes of daylight and the longest day is December 1, with 10 hours, 59 minutes of daylight.
Hours of Daylight and Twilight in December
The earliest sunrise of the month in San Juan del Río is 6:59 AM on December 1 and the latest sunrise is 16 minutes later at 7:15 AM on December 31.
The earliest sunset is 5:58 PM on December 1 and the latest sunset is 12 minutes later at 6:10 PM on December 31.
Daylight saving time is observed in San Juan del Río during 2019, but it neither starts nor ends during December, so the entire month is in standard time.
For reference, on June 21, the longest day of the year, the Sun rises at 7:00 AM and sets 13 hours, 22 minutes later, at 8:22 PM, while on December 22, the shortest day of the year, it rises at 7:11 AM and sets 10 hours, 54 minutes later, at 6:05 PM.
Sunrise & Sunset with Twilight in December
The chance that a given day will be muggy in San Juan del Río is essentially constant during December, remaining around 0% throughout.
For reference, on July 3, the muggiest day of the year, there are muggy conditions 0% of the time, while on January 1, the least muggy day of the year, there are muggy conditions 0% of the time.
Humidity Comfort Levels in December
dry 55°F comfortable 60°F humid 65°F muggy 70°F oppressive 75°F miserable
The average hourly wind speed in San Juan del Río is essentially constant during December, remaining within 0.1 miles per hour of 7.2 miles per hour throughout.
For reference, on March 13, the windiest day of the year, the daily average wind speed is 8.5 miles per hour, while on December 22, the calmest day of the year, the daily average wind speed is 7.1 miles per hour.
The lowest daily average wind speed during December is 7.1 miles per hour on December 22.
Average Wind Speed in December
The hourly average wind direction in San Juan del Río throughout December is predominantly from the east, with a peak proportion of 44% on December 1.
Wind Direction in December
While it does not do so every year, freezing temperatures are seen in San Juan del Río over some winters. The day least likely to be in the growing season is January 2, with a 69% chance.
Time Spent in Various Temperature Bands and the Growing Season in December
The average accumulated growing degree days in San Juan del Río are increasing during December, increasing by 256°F, from 4,777°F to 5,033°F, over the course of the month.
Growing Degree Days in December
The average daily incident shortwave solar energy in San Juan del Río is essentially constant during December, remaining within 0.1 kWh of 4.9 kWh throughout.
The lowest average daily incident shortwave solar energy during December is 4.8 kWh on December 22.
Average Daily Incident Shortwave Solar Energy in December
For the purposes of this report, the geographical coordinates of San Juan del Río are 20.389 deg latitude, -99.996 deg longitude, and 6,398 ft elevation.
The topography within 2 miles of San Juan del Río contains significant variations in elevation, with a maximum elevation change of 715 feet and an average elevation above sea level of 6,370 feet. Within 10 miles contains significant variations in elevation (2,625 feet). Within 50 miles contains large variations in elevation (9,803 feet).
The area within 2 miles of San Juan del Río is covered by artificial surfaces (63%) and cropland (31%), within 10 miles by grassland (42%) and cropland (22%), and within 50 miles by shrubs (32%) and cropland (23%).
This report illustrates the typical weather in San Juan del Río year round, 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 San Juan del Río.
For each station, the records are corrected for the elevation difference between that station and San Juan del Río 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 San Juan del Río is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between San Juan del Río and a given station.
The stations contributing to this reconstruction are: Querétaro Intercontinental Airport (84%, 32 kilometers, northwest); Licenciado Adolfo López Mateos International Airport (9%, 125 kilometers, south); and Tulancingo (7%, 173 kilometers, east).
Time zones for aiports and weather stations are provided by AskGeo.com .