Average Weather in Granite Falls Washington, United States
In Granite Falls, the summers are short, comfortable, and partly cloudy and the winters are chilly, wet, and overcast. Over the course of the year, the temperature typically varies from 33°F to 77°F and is rarely below 22°F or above 86°F.
The warm season lasts for 2.8 months, from June 22 to September 17, with an average daily high temperature above 70°F. The hottest day of the year is August 3, with an average high of 77°F and low of 54°F.
The cool season lasts for 3.4 months, from November 13 to February 25, with an average daily high temperature below 50°F. The coldest day of the year is December 20, with an average low of 33°F and high of 43°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 Granite Falls, 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 Granite Falls begins around June 20 and lasts for 3.5 months, ending around October 6. On August 3, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 71% of the time, and overcast or mostly cloudy 29% of the time.
The cloudier part of the year begins around October 6 and lasts for 8.5 months, ending around June 20. On November 30, the cloudiest day of the year, the sky is overcast or mostly cloudy 77% of the time, and clear, mostly clear, or partly cloudy 22% of the time.
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. The chance of wet days in Granite Falls varies very significantly throughout the year.
The wetter season lasts 6.8 months, from October 9 to May 2, with a greater than 36% chance of a given day being a wet day. The chance of a wet day peaks at 62% on November 18.
The drier season lasts 5.2 months, from May 2 to October 9. The smallest chance of a wet day is 10% on August 1.
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 60% on November 18.
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. Granite Falls experiences extreme seasonal variation in monthly rainfall.
Rain falls throughout the year in Granite Falls. The most rain falls during the 31 days centered around November 20, with an average total accumulation of 10.3 inches.
The least rain falls around July 30, with an average total accumulation of 0.9 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. Granite Falls experiences some seasonal variation in monthly liquid-equivalent snowfall.
The snowy period of the year lasts for 2.7 months, from November 25 to February 16, 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 9.3 months, from February 16 to November 25. The least snow falls around July 16, with an average total liquid-equivalent accumulation of 0.0 inches.
Average Liquid-Equivalent Monthly Snowfall
The length of the day in Granite Falls varies extremely over the course of the year. In 2017, the shortest day is December 21, with 8 hours, 22 minutes of daylight; the longest day is June 21, with 16 hours, 4 minutes of daylight.
Hours of Daylight and Twilight
The earliest sunrise is at 5:07 AM on June 16, and the latest sunrise is 2 hours, 51 minutes later at 7:58 AM on November 4. The earliest sunset is at 4:14 PM on December 10, and the latest sunset is 4 hours, 58 minutes later at 9:11 PM on June 25.
Daylight saving time (DST) is observed in Granite Falls during 2017, starting in the spring on March 12, lasting 7.8 months, and ending in the fall on November 5.
Sunrise & Sunset with Twilight and Daylight Saving Time
The perceived humidity level in Granite Falls, 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 Granite Falls experiences mild seasonal variation over the course of the year.
The windier part of the year lasts for 5.8 months, from October 16 to April 10, with average wind speeds of more than 2.0 miles per hour. The windiest day of the year is December 29, with an average hourly wind speed of 2.7 miles per hour.
The calmer time of year lasts for 6.2 months, from April 10 to October 16. The calmest day of the year is August 9, with an average hourly wind speed of 1.3 miles per hour.
Average Wind Speed
The predominant average hourly wind direction in Granite Falls varies throughout the year.
The wind is most often from the south for 2.1 months, from February 28 to April 30 and for 2.3 months, from September 13 to November 22, with a peak percentage of 46% on March 24. The wind is most often from the west for 4.4 months, from April 30 to September 13, with a peak percentage of 53% on July 20. The wind is most often from the east for 3.2 months, from November 22 to February 28, with a peak percentage of 53% on January 1.
Granite Falls is located near a large body of water (e.g., ocean, sea, or large lake). This section reports on the wide-area average surface temperature of that water.
The average water temperature experiences some seasonal variation over the course of the year.
The time of year with warmer water lasts for 3.1 months, from June 24 to September 26, with an average temperature above 53°F. The day of the year with the warmest water is August 7, with an average temperature of 55°F.
The time of year with cooler water lasts for 4.1 months, from December 8 to April 10, with an average temperature below 48°F. The day of the year with the coolest water is February 11, with an average temperature of 46°F.
Average Water Temperature
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 16 to August 22, with an average daily incident shortwave energy per square meter above 5.4 kWh. The brightest day of the year is July 21, with an average of 6.6 kWh.
The darker period of the year lasts for 3.9 months, from October 23 to February 19, with an average daily incident shortwave energy per square meter below 2.0 kWh. The darkest day of the year is December 25, with an average of 0.8 kWh.
Average Daily Incident Shortwave Solar Energy
For the purposes of this report, the geographical coordinates of Granite Falls are 48.084 deg latitude, -121.969 deg longitude, and 443 ft elevation.
The topography within 2 miles of Granite Falls contains very significant variations in elevation, with a maximum elevation change of 938 feet and an average elevation above sea level of 419 feet. Within 10 miles contains very significant variations in elevation (5,249 feet). Within 50 miles also contains extreme variations in elevation (10,764 feet).
The area within 2 miles of Granite Falls is covered by trees (79%) and artificial surfaces (16%), within 10 miles by trees (71%) and artificial surfaces (14%), and within 50 miles by trees (53%) and water (16%).
This report illustrates the typical weather in Granite Falls, 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 Granite Falls.
For each station, the records are corrected for the elevation difference between that station and Granite 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 Granite Falls is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Granite Falls and a given station.
The stations contributing to this reconstruction are: Arlington Municipal Airport (66%, 17 kilometers, northwest); Snohomish County Airport (Paine Field) (32%, 30 kilometers, southwest); and Omak Airport (2.1%, 186 kilometers, east).
Time zones for aiports and weather stations are provided by AskGeo.com .