Average Weather in December in Post Falls Idaho, United States
Daily high temperatures decrease by 4°F, from 38°F to 33°F, rarely falling below 22°F or exceeding 47°F. The lowest daily average high temperature is 33°F on December 29.
Daily low temperatures decrease by 4°F, from 28°F to 24°F, rarely falling below 10°F or exceeding 38°F.
For reference, on August 3, the hottest day of the year, temperatures in Post Falls typically range from 56°F to 87°F, while on January 1, the coldest day of the year, they range from 24°F to 33°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 Post Falls experiences essentially constant cloud cover, with the percentage of time that the sky is overcast or mostly cloudy remaining about 73% throughout the month.
The clearest day of the month is December 11, with clear, mostly clear, or partly cloudy conditions 28% of the time.
For reference, on January 10, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 75%, while on August 1, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 79%.
Cloud Cover Categories in December
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. In Post Falls, the chance of a wet day over the course of December is rapidly decreasing, starting the month at 42% and ending it at 35%.
For reference, the year's highest daily chance of a wet day is 42% on November 28, and its lowest chance is 8% on August 4.
Over the course of December in Post Falls, the chance of a day with only rain decreases from 30% to 17%, the chance of a day with mixed snow and rain remains an essentially constant 7% throughout, and the chance of a day with only snow increases from 5% to 11%.
Probability of Precipitation in December
The average sliding 31-day rainfall during December in Post Falls is decreasing, starting the month at 2.9 inches, when it rarely exceeds 4.6 inches or falls below 1.1 inches, and ending the month at 2.0 inches, when it rarely exceeds 3.6 inches or falls below 0.5 inches.
Average Monthly Rainfall in December
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. As with rainfall, we consider the liquid-equivalent snowfall accumulated over a sliding 31-day period centered around each day.
The average sliding 31-day liquid-equivalent snowfall during December in Post Falls is gradually increasing, starting the month at 0.5 inches, when it rarely exceeds 0.9 inches, and ending the month at 0.8 inches, when it rarely exceeds 1.6 inches or falls below 0.1 inches.
The highest average 31-day liquid-equivalent accumulation is 0.8 inches on December 31.
Average Monthly Liquid-Equivalent Snowfall in December
Over the course of December in Post Falls, the length of the day is essentially constant. The shortest day of the month is December 21, with 8 hours, 25 minutes of daylight and the longest day is December 1, with 8 hours, 42 minutes of daylight.
Hours of Daylight and Twilight in December
The earliest sunrise of the month in Post Falls is 7:15 AM on December 1 and the latest sunrise is 21 minutes later at 7:36 AM on December 31.
The earliest sunset is 3:55 PM on December 11 and the latest sunset is 10 minutes later at 4:05 PM on December 31.
Daylight saving time is observed in Post Falls during 2018, 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 4:49 AM and sets 16 hours, 0 minutes later, at 8:49 PM, while on December 21, the shortest day of the year, it rises at 7:33 AM and sets 8 hours, 25 minutes later, at 3:58 PM.
Sunrise & Sunset with Twilight and Daylight Saving Time in December
The chance that a given day will be muggy in Post Falls is essentially constant during December, remaining around 0% throughout.
For reference, on July 27, 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
The average hourly wind speed in Post Falls is essentially constant during December, remaining within 0.1 miles per hour of 5.1 miles per hour throughout.
For reference, on March 27, the windiest day of the year, the daily average wind speed is 5.6 miles per hour, while on August 3, the calmest day of the year, the daily average wind speed is 4.9 miles per hour.
Average Wind Speed in December
Wind Direction in December
The growing season in Post Falls typically lasts for 5.3 months (162 days), from around May 2 to around October 11, rarely starting before April 11 or after May 22, and rarely ending before September 21 or after October 30.
The month of December in Post Falls is reliably fully outside of the growing season.
Time Spent in Various Temperature Bands and the Growing Season in December
The average accumulated growing degree days in Post Falls are essentially constant during December, remaining within 1°F of 2,174°F throughout.
Growing Degree Days in December
The average daily incident shortwave solar energy in Post Falls is essentially constant during December, remaining around 1.0 kWh throughout.
The lowest average daily incident shortwave solar energy during December is 1.0 kWh on December 26.
Average Daily Incident Shortwave Solar Energy in December
For the purposes of this report, the geographical coordinates of Post Falls are 47.718 deg latitude, -116.952 deg longitude, and 2,185 ft elevation.
The topography within 2 miles of Post Falls contains significant variations in elevation, with a maximum elevation change of 673 feet and an average elevation above sea level of 2,192 feet. Within 10 miles contains significant variations in elevation (3,241 feet). Within 50 miles contains large variations in elevation (5,305 feet).
The area within 2 miles of Post Falls is covered by artificial surfaces (35%), shrubs (25%), grassland (18%), and cropland (13%), within 10 miles by shrubs (37%) and trees (30%), and within 50 miles by trees (40%) and shrubs (28%).
This report illustrates the typical weather in Post Falls 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 Post Falls.
For each station, the records are corrected for the elevation difference between that station and Post Falls 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 Post Falls is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Post Falls and a given station.
The stations contributing to this reconstruction are: Coeur D'Alene Air Terminal (77%, 11 kilometers, northeast); Felts Field (21%, 28 kilometers, west); and Pullman–Moscow Regional Airport (2.8%, 109 kilometers, south).
All other weather data, including cloud cover, precipitation, wind speed and direction, and solar flux, come from NASA's MERRA-2 Modern-Era Retrospective Analysis . This reanalysis combines a variety of wide-area measurements in a state-of-the-art global meteorological model to reconstruct the hourly history of weather throughout the world on a 50-kilometer grid.
Time zones for aiports and weather stations are provided by AskGeo.com .