Average Weather in April in Fort Lewis Washington, United States
Daily high temperatures increase by 6°F, from 57°F to 63°F, rarely falling below 49°F or exceeding 75°F.
Daily low temperatures increase by 4°F, from 39°F to 43°F, rarely falling below 31°F or exceeding 50°F.
For reference, on August 3, the hottest day of the year, temperatures in Fort Lewis typically range from 55°F to 79°F, while on December 20, the coldest day of the year, they range from 35°F to 45°F.
Average High and Low Temperature in April
The figure below shows you a compact characterization of the hourly average temperatures for the quarter of the year centered on April. 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 April
The month of April in Fort Lewis experiences decreasing cloud cover, with the percentage of time that the sky is overcast or mostly cloudy decreasing from 70% to 59%.
The clearest day of the month is April 30, with clear, mostly clear, or partly cloudy conditions 41% of the time.
For reference, on January 16, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 76%, while on August 3, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 77%.
Cloud Cover Categories in April
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 Fort Lewis, the chance of a wet day over the course of April is very rapidly decreasing, starting the month at 46% and ending it at 34%.
For reference, the year's highest daily chance of a wet day is 58% on November 18, and its lowest chance is 7% on August 4.
Probability of Precipitation in April
The average sliding 31-day rainfall during April in Fort Lewis is rapidly decreasing, starting the month at 4.4 inches, when it rarely exceeds 7.3 inches or falls below 2.1 inches, and ending the month at 2.8 inches, when it rarely exceeds 4.7 inches or falls below 1.0 inches.
Average Monthly Rainfall in April
Over the course of April in Fort Lewis, the length of the day is rapidly increasing. From the start to the end of the month, the length of the day increases by 1 hour, 33 minutes, implying an average daily increase of 3 minutes, 13 seconds, and weekly increase of 22 minutes, 30 seconds.
The shortest day of the month is April 1, with 12 hours, 51 minutes of daylight and the longest day is April 30, with 14 hours, 24 minutes of daylight.
Hours of Daylight and Twilight in April
The latest sunrise of the month in Fort Lewis is 6:49 AM on April 1 and the earliest sunrise is 53 minutes earlier at 5:55 AM on April 30.
The earliest sunset is 7:40 PM on April 1 and the latest sunset is 40 minutes later at 8:19 PM on April 30.
Daylight saving time is observed in Fort Lewis during 2018, but it neither starts nor ends during April, so the entire month is in daylight saving time.
For reference, on June 21, the longest day of the year, the Sun rises at 5:14 AM and sets 15 hours, 55 minutes later, at 9:09 PM, while on December 21, the shortest day of the year, it rises at 7:53 AM and sets 8 hours, 30 minutes later, at 4:23 PM.
Sunrise & Sunset with Twilight and Daylight Saving Time in April
The chance that a given day will be muggy in Fort Lewis is essentially constant during April, remaining around 0% throughout.
For reference, on September 13, 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 April
dry 55°F comfortable 60°F humid 65°F muggy 70°F oppressive 75°F miserable
The average hourly wind speed in Fort Lewis is gradually decreasing during April, decreasing from 4.5 miles per hour to 4.0 miles per hour over the course of the month.
For reference, on November 30, the windiest day of the year, the daily average wind speed is 5.2 miles per hour, while on August 2, the calmest day of the year, the daily average wind speed is 3.2 miles per hour.
Average Wind Speed in April
Wind Direction in April
Fort Lewis 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 Fort Lewis is gradually increasing during April, rising by 3°F, from 48°F to 51°F, over the course of the month.
Average Water Temperature in April
The growing season in Fort Lewis typically lasts for 6.3 months (193 days), from around April 18 to around October 28, rarely starting before March 30 or after May 10, and rarely ending before October 9 or after November 21.
During April in Fort Lewis, the chance that a given day is within the growing season is very rapidly increasing rising from 14% to 76% over the course of the month.
Time Spent in Various Temperature Bands and the Growing Season in April
The average accumulated growing degree days in Fort Lewis are gradually increasing during April, increasing by 81°F, from 56°F to 137°F, over the course of the month.
Growing Degree Days in April
The average daily incident shortwave solar energy in Fort Lewis is increasing during April, rising by 1.4 kWh, from 3.7 kWh to 5.1 kWh, over the course of the month.
Average Daily Incident Shortwave Solar Energy in April
For the purposes of this report, the geographical coordinates of Fort Lewis are 47.108 deg latitude, -122.577 deg longitude, and 279 ft elevation.
The topography within 2 miles of Fort Lewis contains only modest variations in elevation, with a maximum elevation change of 217 feet and an average elevation above sea level of 276 feet. Within 10 miles contains only modest variations in elevation (518 feet). Within 50 miles contains significant variations in elevation (14,383 feet).
The area within 2 miles of Fort Lewis is covered by artificial surfaces (69%), water (16%), and trees (15%), within 10 miles by artificial surfaces (36%) and trees (36%), and within 50 miles by trees (53%) and shrubs (17%).
This report illustrates the typical weather in Fort Lewis 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 Fort Lewis.
For each station, the records are corrected for the elevation difference between that station and Fort Lewis 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 Fort Lewis is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Fort Lewis and a given station.
The stations contributing to this reconstruction are: Madigan Hospital Heliport (83%, 2.8 kilometers, south); McChord Field Airport (Joint Base Lewis-McChord) (16%, 9 kilometers, northeast); and Sanderson Field (1.3%, 45 kilometers, west).
Time zones for aiports and weather stations are provided by AskGeo.com .