Average Weather in May in Kelso Washington, United States
Daily high temperatures increase by 5°F, from 64°F to 69°F, rarely falling below 54°F or exceeding 81°F.
Daily low temperatures increase by 5°F, from 44°F to 49°F, rarely falling below 37°F or exceeding 55°F.
For reference, on August 3, the hottest day of the year, temperatures in Kelso typically range from 56°F to 79°F, while on January 1, the coldest day of the year, they range from 35°F to 45°F.
Average High and Low Temperature in May
The figure below shows you a compact characterization of the hourly average temperatures for the quarter of the year centered on May. 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 May
The month of May in Kelso experiences gradually decreasing cloud cover, with the percentage of time that the sky is overcast or mostly cloudy decreasing from 64% to 58%.
The clearest day of the month is May 31, with clear, mostly clear, or partly cloudy conditions 42% of the time.
For reference, on November 30, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 79%, while on August 3, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 78%.
Cloud Cover Categories in May
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 Kelso, the chance of a wet day over the course of May is rapidly decreasing, starting the month at 35% and ending it at 28%.
For reference, the year's highest daily chance of a wet day is 61% on November 18, and its lowest chance is 6% on August 3.
Probability of Precipitation in May
The average sliding 31-day rainfall during May in Kelso is rapidly decreasing, starting the month at 3.3 inches, when it rarely exceeds 5.4 inches or falls below 1.2 inches, and ending the month at 2.3 inches, when it rarely exceeds 4.1 inches or falls below 0.6 inches.
Average Monthly Rainfall in May
Over the course of May in Kelso, 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, 8 minutes, implying an average daily increase of 2 minutes, 17 seconds, and weekly increase of 15 minutes, 56 seconds.
The shortest day of the month is May 1, with 14 hours, 22 minutes of daylight and the longest day is May 31, with 15 hours, 30 minutes of daylight.
Hours of Daylight and Twilight in May
The latest sunrise of the month in Kelso is 5:58 AM on May 1 and the earliest sunrise is 34 minutes earlier at 5:24 AM on May 31.
The earliest sunset is 8:20 PM on May 1 and the latest sunset is 35 minutes later at 8:54 PM on May 31.
Daylight saving time is observed in Kelso during 2018, but it neither starts nor ends during May, so the entire month is in daylight saving time.
For reference, on June 21, the longest day of the year, the Sun rises at 5:20 AM and sets 15 hours, 47 minutes later, at 9:06 PM, while on December 21, the shortest day of the year, it rises at 7:51 AM and sets 8 hours, 37 minutes later, at 4:28 PM.
Sunrise & Sunset with Twilight in May
The chance that a given day will be muggy in Kelso is essentially constant during May, remaining around 0% throughout.
For reference, on August 4, 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 May
dry 55°F comfortable 60°F humid 65°F muggy 70°F oppressive 75°F miserable
The average hourly wind speed in Kelso is essentially constant during May, remaining within 0.1 miles per hour of 3.7 miles per hour throughout.
For reference, on December 3, the windiest day of the year, the daily average wind speed is 5.0 miles per hour, while on August 24, the calmest day of the year, the daily average wind speed is 3.5 miles per hour.
Average Wind Speed in May
Wind Direction in May
Kelso 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 Kelso is gradually increasing during May, rising by 3°F, from 52°F to 55°F, over the course of the month.
Average Water Temperature in May
The growing season in Kelso typically lasts for 6.9 months (211 days), from around April 8 to around November 5, rarely starting before March 12 or after May 3, and rarely ending before October 15 or after December 3.
The month of May in Kelso is more likely than not fully within the growing season, with the chance that a given day is in the growing season increasing from 88% to 100% over the course of the month.
Time Spent in Various Temperature Bands and the Growing Season in May
The average accumulated growing degree days in Kelso are increasing during May, increasing by 189°F, from 163°F to 352°F, over the course of the month.
Growing Degree Days in May
The average daily incident shortwave solar energy in Kelso is gradually increasing during May, rising by 0.8 kWh, from 5.1 kWh to 5.8 kWh, over the course of the month.
Average Daily Incident Shortwave Solar Energy in May
For the purposes of this report, the geographical coordinates of Kelso are 46.147 deg latitude, -122.908 deg longitude, and 62 ft elevation.
The topography within 2 miles of Kelso contains only modest variations in elevation, with a maximum elevation change of 479 feet and an average elevation above sea level of 114 feet. Within 10 miles contains only modest variations in elevation (2,156 feet). Within 50 miles contains large variations in elevation (8,284 feet).
The area within 2 miles of Kelso is covered by artificial surfaces (51%), herbaceous vegetation (28%), and trees (11%), within 10 miles by trees (52%) and shrubs (20%), and within 50 miles by trees (53%) and shrubs (25%).
This report illustrates the typical weather in Kelso 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 Kelso.
For each station, the records are corrected for the elevation difference between that station and Kelso 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 Kelso is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Kelso and a given station.
The stations contributing to this reconstruction are: Southwest Washington Regional Airport (96%, 3.5 kilometers, south); South Lewis County Airport (2.8%, 38 kilometers, north); and Clatsop County Airport (1.1%, 75 kilometers, west).
Time zones for aiports and weather stations are provided by AskGeo.com .