Average Weather in April in Coulee Dam Washington, United States
Daily high temperatures increase by 9°F, from 58°F to 67°F, rarely falling below 50°F or exceeding 79°F.
Daily low temperatures increase by 7°F, from 35°F to 42°F, rarely falling below 28°F or exceeding 51°F.
For reference, on July 31, the hottest day of the year, temperatures in Coulee Dam typically range from 61°F to 90°F, while on January 1, the coldest day of the year, they range from 21°F to 30°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
Ivanivka, Ukraine (5,630 miles away); Kemaliye, Turkey (6,260 miles); and Suluktu, Kyrgyzstan (6,348 miles) are the far-away foreign places with temperatures most similar to Coulee Dam (view comparison).
The month of April in Coulee Dam experiences gradually decreasing cloud cover, with the percentage of time that the sky is overcast or mostly cloudy decreasing from 58% to 50%.
The clearest day of the month is April 30, with clear, mostly clear, or partly cloudy conditions 50% of the time.
For reference, on January 15, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 70%, while on August 3, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 79%.
Cloud Cover Categories in April
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. In Coulee Dam, the chance of a wet day over the course of April is gradually decreasing, starting the month at 17% and ending it at 13%.
For reference, the year's highest daily chance of a wet day is 28% on November 28, and its lowest chance is 5% on August 18.
Probability of Precipitation in April
The average sliding 31-day rainfall during April in Coulee Dam is essentially constant, remaining about 0.7 inches throughout, and rarely exceeding 1.7 inches or falling below 0.2 inches.
The lowest average 31-day accumulation is 0.6 inches on April 22.
Average Monthly Rainfall in April
Over the course of April in Coulee Dam, 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, 36 minutes, implying an average daily increase of 3 minutes, 19 seconds, and weekly increase of 23 minutes, 13 seconds.
The shortest day of the month is April 1, with 12 hours, 52 minutes of daylight and the longest day is April 30, with 14 hours, 29 minutes of daylight.
Hours of Daylight and Twilight in April
The latest sunrise of the month in Coulee Dam is 6:33 AM on April 1 and the earliest sunrise is 55 minutes earlier at 5:39 AM on April 30.
The earliest sunset is 7:26 PM on April 1 and the latest sunset is 41 minutes later at 8:07 PM on April 30.
Daylight saving time is observed in Coulee Dam 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 4:56 AM and sets 16 hours, 3 minutes later, at 8:59 PM, while on December 21, the shortest day of the year, it rises at 7:42 AM and sets 8 hours, 23 minutes later, at 4:05 PM.
Sunrise & Sunset with Twilight and Daylight Saving Time in April
The chance that a given day will be muggy in Coulee Dam is essentially constant during April, remaining around 0% throughout.
For reference, on July 17, 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
The average hourly wind speed in Coulee Dam is essentially constant during April, remaining within 0.1 miles per hour of 6.9 miles per hour throughout.
For reference, on March 26, the windiest day of the year, the daily average wind speed is 7.0 miles per hour, while on January 5, the calmest day of the year, the daily average wind speed is 5.9 miles per hour.
Average Wind Speed in April
Wind Direction in April
The growing season in Coulee Dam typically lasts for 5.7 months (173 days), from around April 24 to around October 14, rarely starting before April 5 or after May 13, and rarely ending before September 27 or after October 31.
During April in Coulee Dam, the chance that a given day is within the growing season is very rapidly increasing rising from 6% to 67% 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 Coulee Dam are gradually increasing during April, increasing by 117°F, from 34°F to 151°F, over the course of the month.
Growing Degree Days in April
The average daily incident shortwave solar energy in Coulee Dam is rapidly increasing during April, rising by 1.5 kWh, from 4.3 kWh to 5.9 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 Coulee Dam are 47.965 deg latitude, -118.976 deg longitude, and 1,768 ft elevation.
The topography within 2 miles of Coulee Dam contains very significant variations in elevation, with a maximum elevation change of 1,539 feet and an average elevation above sea level of 1,633 feet. Within 10 miles contains very significant variations in elevation (3,510 feet). Within 50 miles also contains extreme variations in elevation (6,355 feet).
The area within 2 miles of Coulee Dam is covered by shrubs (84%) and water (14%), within 10 miles by shrubs (68%) and cropland (11%), and within 50 miles by shrubs (48%) and cropland (16%).
This report illustrates the typical weather in Coulee Dam 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 Coulee Dam.
For each station, the records are corrected for the elevation difference between that station and Coulee Dam 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 Coulee Dam is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Coulee Dam and a given station.
The stations contributing to this reconstruction are: Omak Airport (44%, 68 kilometers, northwest); Ephrata Municipal Airport (33%, 84 kilometers, southwest); and Fairchild Air Force Base (23%, 106 kilometers, east).
Time zones for aiports and weather stations are provided by AskGeo.com .