Average Weather in October in Granite Falls Washington, United States
In Granite Falls, the month of October is characterized by rapidly falling daily high temperatures, with daily highs decreasing by 11°F, from 65°F to 54°F over the course of the month, and rarely exceeding 75°F or dropping below 47°F.
Daily low temperatures decrease by 5°F, from 47°F to 42°F, rarely falling below 32°F or exceeding 54°F.
For reference, on August 3, the hottest day of the year, temperatures in Granite Falls typically range from 54°F to 77°F, while on December 20, the coldest day of the year, they range from 33°F to 43°F.
Average High and Low Temperature in October
The figure below shows you a compact characterization of the hourly average temperatures for the quarter of the year centered on October. 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 October
The month of October in Granite Falls experiences very rapidly increasing cloud cover, with the percentage of time that the sky is overcast or mostly cloudy increasing from 51% to 71%.
The clearest day of the month is October 1, with clear, mostly clear, or partly cloudy conditions 49% of the time.
For reference, on November 30, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 77%, while on August 3, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 71%.
Cloud Cover in October
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. In Granite Falls, the chance of a wet day over the course of October is very rapidly increasing, starting the month at 32% and ending it at 54%.
For reference, the year's highest daily chance of a wet day is 62% on November 19, and its lowest chance is 10% on August 5.
Probability of Precipitation in October
To show variation within the month and not just the monthly total, we show the rainfall accumulated over a sliding 31-day period centered around each day.
The average sliding 31-day rainfall during October in Granite Falls is very rapidly increasing, starting the month at 4.0 inches, when it rarely exceeds 7.5 inches or falls below 0.9 inches, and ending the month at 8.6 inches, when it rarely exceeds 13.5 inches or falls below 4.1 inches.
Average Monthly Rainfall in October
Over the course of October in Granite Falls, the length of the day is rapidly decreasing. From the start to the end of the month, the length of the day decreases by 1 hour, 40 minutes, implying an average daily decrease of 3 minutes, 21 seconds, and weekly decrease of 23 minutes, 27 seconds.
The shortest day of the month is October 31, with 9 hours, 58 minutes of daylight and the longest day is October 1, with 11 hours, 39 minutes of daylight.
Hours of Daylight and Twilight in October
The earliest sunrise of the month in Granite Falls is 7:07 AM on October 1 and the latest sunrise is 44 minutes later at 7:52 AM on October 31.
The latest sunset is 6:46 PM on October 1 and the earliest sunset is 56 minutes earlier at 5:50 PM on October 31.
Daylight saving time is observed in Granite Falls during 2017, but it neither starts nor ends during October, so the entire month is in daylight saving time.
For reference, on June 21, the longest day of the year, the Sun rises at 5:07 AM and sets 16 hours, 4 minutes later, at 9:11 PM, while on December 21, the shortest day of the year, it rises at 7:55 AM and sets 8 hours, 22 minutes later, at 4:16 PM.
Sunrise & Sunset with Twilight and Daylight Saving Time in October
We base the humidity comfort level on the dew point, as it determines whether perspiration will evaporate from the skin, thereby cooling the body. Lower dew points feel drier and higher dew points feel more humid. Unlike temperature, which typically varies significantly between night and day, dew point tends to change more slowly, so while the temperature may drop at night, a muggy day is typically followed by a muggy night.
The chance that a given day will be muggy in Granite Falls is essentially constant during October, remaining around 0% throughout.
For reference, on August 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 October
This section discusses the wide-area hourly average wind vector (speed and direction) at 10 meters above the ground. The wind experienced at any given location is highly dependent on local topography and other factors, and instantaneous wind speed and direction vary more widely than hourly averages.
The average hourly wind speed in Granite Falls is gradually increasing during October, increasing from 1.8 miles per hour to 2.3 miles per hour over the course of the month.
For reference, on December 29, the windiest day of the year, the daily average wind speed is 2.7 miles per hour, while on August 9, the calmest day of the year, the daily average wind speed is 1.3 miles per hour.
Average Wind Speed in October
Wind Direction in October
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 surface water temperature in Granite Falls is gradually decreasing during October, falling by 2°F, from 53°F to 51°F, over the course of the month.
Average Water Temperature in October
This section discusses the total daily incident shortwave solar energy reaching the surface of the ground over a wide area, taking full account of seasonal variations in the length of the day, the elevation of the Sun above the horizon, and absorption by clouds and other atmospheric constituents. Shortwave radiation includes visible light and ultraviolet radiation.
The average daily incident shortwave solar energy in Granite Falls is rapidly decreasing during October, falling by 1.7 kWh, from 3.3 kWh to 1.6 kWh, over the course of the month.
Average Daily Incident Shortwave Solar Energy in October
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 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 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).
All data relating to the Sun's position (e.g., sunrise and sunset) are computed using astronomical formulas from the book, Astronomical Tables of the Sun, Moon and Planets , by Jean Meeus.
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.
Land Use data comes from the Global Land Cover SHARE database , published by the Food and Agriculture Organization of the United Nations.
Elevation data comes from the Shuttle Radar Topography Mission (SRTM) , published by NASA's Jet Propulsion Laboratory.
Names, locations, and time zones of places and some airports come from the GeoNames Geographical Database .
Time zones for aiports and weather stations are provided by AskGeo.com .
Maps are © Esri, with data from National Geographic, Esri, DeLorme, NAVTEQ, UNEP-WCMC, USGS, NASA, ESA, METI, NRCAN, GEBCO, NOAA, and iPC.