Washington mainly exhibits continental climate (Köppen climate classification Csb, Cfb, Dfb) in the west and semi-arid type in the east (Köppen BS, BW) of the Cascade Range. Idaho in the east, Oregon in the south, the Pacific Ocean to the west, and the Canadian province of British Columbia in the north, border the state. The climate varies substantially from west to east, spanning from oceanic, Mediterranean, and subarctic to semi-arid. The Pacific Ocean, the Olympic, and Cascade mountains chiefly influence the climate of the state.
Washington, the Evergreen State, lies at the extreme northwest of the United States, with an average elevation of 520 meters above seas level. The Cascade Range that runs north-south bisects the state into a wet western part and a dry eastern part. The topography consists of high mountains, volcanoes, dense forests, temperate rainforests, rivers, semi-arid steppe, and deserts. The rain shadow region of the Cascade Mountains receives scanty rainfall of 6" (152.4mm), while the windward side sees abundant snowfall that reaches 200" (5080mm) annually. The temperate rainforests lie on the western side of the Olympic Peninsula, where the annual rainfall crosses a massive 160" (4064mm).
Summers in western Washington are fresh and relatively dry, while they are warmer in the east. The average high temperatures peak at 78°F (25.6°C) in July, while day temperatures reach 105°F (40.6°C) to 115°F (46.1°C) in many places in the east. Winters are mild and wet, with mainly cloudy skies, and long-lasting drizzly rain. The average low temperatures drop to 23°F (-5°C) in January, while night temperatures regularly dip between -10°F (-23.3°C) to -20°F (-28.9°C). Wind speeds reach 40 to 50 miles per hour during the cold months. Chinook winds that rapidly raise temperatures occasionally blow during the winter. Thunderstorms occur for four to eight days in the lowlands and seven to fifteen days in the mountains. A few hailstorms cause damage to crops during the winter.
The average annual precipitation is an ample 42" (1066.8mm) in Washington. The precipitation varies from 20" (508mm) in the rain shadow of the Olympus mountains region to 150" (3810mm) on the windward side of the mountains. Rainfall is light to moderate but lasts for long periods. The annual rainfall varies from 7" (177.8mm) to 9" (228.6mm) at the confluence of the Snake and Columbia Rivers, to 15" (381mm) to 30" (762mm) along the eastern border. Fog can last up to noon during late summer and early fall in the lowlands, while higher elevations are sunny. Snowfall varies from 10" (254mm) in the Puget Sound area to 75" (1905mm) in eastern Washington. Snow remains on the ground until June at higher elevations, while mountain peaks above 2500 meters remain snow-capped throughout the summer. Mount Rainer and Mount Baker record some of the most significant snowfall and snow depths in the United States. Washington records 126 to 200 sunny days annually.
The highest temperature on record in Washington is 118°F (47.8°C) at Ice Harbor Dam on August 5, 1961, while Winthrop and Mazama recorded the lowest temperature of -48°F (-44.4°C) on December 30, 1965.
The best time to visit Washington
The best time to visit Washington is from June to September during summer and early fall seasons. The skies are clear, the days are sunny, and the conditions are pleasant. The temperatures range from warm to moderately hot across the state. Camping, fishing, and hiking in the higher mountain lakes and streams region begins after the melting of snow in late spring and lasts until fall. The exciting whale watching season lasts from April to October. Summer is the peak tourist season, but May and September have pleasant weather and fewer crowds.
The worst time to visit Washington
The worst time to visit Washington is from December to February in the cold season. Winters are severely cold in the majority of the state. The skies are gray, the conditions are chilly, and the atmosphere is wet. Moist air from the ocean and the formation of the low-pressure center during fall and winter starts the wet season by the beginning of October. Rainfall is heavy in the high and windward side of the mountains. Snowfall is massive in the highlands and ample in the rest of the state except for the coastal regions. Strong winds with speeds of 50 miles per hour add to the chill factor. Winter sports attract many tourists to mountain resorts with activities like skiing, snowboarding, and snowshoeing.
Washington lies in the Pacific Ring of Fire and the Cascade Volcanic Arc, which is susceptible to frequent volcanic and seismic disturbances. Mount Rainier has a history of large, destructive eruptions, while Mount St. Helens last erupted in 1980. Additionally, Washington is prone to wildfires, thunderstorms, floods, and snowstorms in late spring, summer, and winter. The melting of snow causes flooding in low-lying areas during late spring. Snowstorms are frequent in the winter and blizzards deposit massive amounts of snow in the upper mountain ranges.
Weather in January
January is usually the coldest month of the year in Washington as the temperatures drop alarmingly. The bottom may hit -25°F (-31.7°C) or lower in many areas such as Leavenworth and Winthrop. The average low temperatures are in the frigid 18°F (-7.8°C) to 28°F (-2.2°C), while the average high temperatures are in the cold 30°F (-1.1°C) to 40°F (4.4°C) zone, with mild temperatures in the coastal regions. The coastal belt and mountain slopes are rainy with 12" (304.8mm) to 15" (381mm) of rainfall, which makes the conditions challenging, especially with heavy snow at high altitudes. January is the snowiest month, with lower mountain slopes receiving 15" (381mm) to 20" (508mm) of snow, and upper ranges crossing 100" (2540mm). The days are short, and the sunlight hardly lasts for 3 hours. The Snoqualmie Pass area in the Cascade Mountains is one of the famous places for skiing, snowshoeing, and snow tubing activities. Warm winter clothes are necessary, and while it is fun to head for the mountains, watch out for blizzards.
Weather in February
February is cold in Washington with gray skies, chilly winds, and plenty of snow. The average low temperatures are in the freezing 21°F (-6.1°C) to 31°F (-0.6°C) zone, while the average high temperatures are in the mild 36°F (2.2°C) to 46°F (7.8°C) zone across the state. Olympia, the capital in the Puget Sound area, averages between 33°F (0.6°C) to 49°F (9.4°C), while Wenatchee in the east is cold between 26°F (-3.3°C) to 44°F (6.7°C). Short days and chilly evenings require layered clothing. The precipitation is seldom more than a drizzle but can last for annoyingly long periods. Snowstorms occur regularly at high altitudes and sporadically in the lowlands. Mount Rainier registers an average of 91" (2311.4mm) of snow in February. There is nothing sweeter than sitting by a cozy fireplace and sipping hot drinks or eating tasty food in the cold winter weather. Remember that fog makes it challenging to take clear pictures. Washington coastal areas fare better during the cold in February.
Weather in March
March is cold in Washington during the early days of the beautiful spring season. Day temperatures rise a little to register in the average 43°F (6.1°C) to 53°F (11.7°C) range, while the average night temperatures remain in the cold 25°F (-3.9°C) to 35°F (1.7°C) range. The skies are cloudy, and the conditions are wet, as the state receives an average of 4.3" (109.2mm) of rainfall. Seattle rarely has freezing nights with temperatures in the 40°F (4.4°C) to 55°F (12.8°C), while Spokane in the east is cold between 32°F (0°C) to 49°F (9.4°C). The snowfall is light in the east and negligible in the west, but the mountains receive vast amounts. The weather is unpredictable in spring as sunny days alternate between cloudy and cold ones. Do not expect the coastal region to be dry and sunny for the entire month as low-pressure belts often bring rain in early spring. Wear warm jackets, which can take care of the precipitation, especially on cruises and whale watching tours as the season begins in March in Washington.
Weather in April
April steadily increases the temperatures in Washington with the advance of the spring season. Snow disappears on the ground by the end of the month except for the upper mountain ranges. The precipitation ceases considerably and registers an average of 2.9" (73.7mm) in the state. The average high temperatures are between a warm 50°F (10°C) to 60°F (15.6°C), while the average low temperatures drop to the cold 30°F (-1.1°C) to 40°F (4.4°C) zone. Aberdeen in the west has warm temperatures between 41°F (5°C) to 57°F (13.9°C), while Darrington in the Cascades registers between 39°F (3.9°C) to 62°F (16.7°C). Mount Baker ski area is busy in the spring season with abundant snow for skiing, snowboarding, and sledding. Tulips, daffodils, and many wildflowers bloom to create a merry atmosphere in the beautiful spring. Scenic waterfront trails, roaring fresh waterfalls, and beautiful lakes are irresistible calls of the wild that few visitors can ignore. Drive carefully as the roads are slippery with the melting of snow and ice in April in Washington.
Weather in May
May is a wonderful spring month in Washington with warm weather. The average high temperatures are in the pleasant 58°F (14.4°C) to 68°F (20°C) zone, while the nights are mild in the average range of 35°F (1.7°C) to 45°F (7.2°C). Chirping birds, regular spotting of wildlife in the natural preserves, fresh aroma of flowers, fresh water in the lakes and rivers, and the warmth of the sun enlighten the spirit. Biking, hiking, kayaking, and fishing are quite enjoyable in comfortable weather. The sunshine improves significantly, but occasional arctic cold fronts can push down the temperatures briefly. The warm sun pushes the rain and snow to the background. The warm ocean waters bring hordes of whales to the west coast of Washington. The visitor footfall increases in May with the beginning of the tourist season. May is an excellent time to visit Washington to beat the summer crowds in the pleasant spring weather. Wear warm clothes as the sunshine is moderate.
Weather in June
June begins the warm summer season in Washington with moderate sunshine and dry conditions. The average high temperatures are in the wonderful 65°F (18.3°C) to 75°F (23.9°C) range, while average low temperatures are in the comfortable 40°F (4.4°C) to 50°F (10°C) zone. The highlands are sunny, while the low valley regions often remain foggy till noon. Long Beach on the west coast attracts tourists with average temperatures between 50°F (10°C) to 62°F (16.7°C), while the famous Walla Walla in the east averages between 54°F (12.2°C) to 79°F (26.1°C). The rain ceases in the state as June sees 15 to 20 sunny days. The bright weather and calm waters are ideal for surfing, canoeing, and kayaking in the water. Summer is a perfect time for fishing and hunting, swimming in the serene lakes, and biking and hiking the wilderness. Watch out for thunderstorms in the mountains. Light summer clothing is sufficient in the day, while a light sweater makes the nights comfortable in June in Washington.
Weather in July
July is the hottest and driest month of the year in Washington with the average high temperatures in the range of 73°F (22.8°C) to 83°F (28.3°C) and the average low temperatures in the 45°F (7.2°C) to 55°F (12.8°C) zone. Clearwater on the west coast sees pleasant temperatures between 49°F (9.4°C) to 71°F (21.7°C), while Seattle is in the warm 57°F (13.9°C) to 76°F (24.4°C) zone. The occasional light rainfall allows visitors to be free from the weight of umbrellas. Jackets may yet come handy in the cool evenings in the upper mountain ranges. The Puget Sound region receives a good amount of sunshine and sees clear skies for long periods. The prevalent fog over the ocean and Strait of Juan de Fuca results in cloudy skies along the coast and nearby areas. Western Washington has temperate conditions, but a few places touch the 100°F (37.8°C) mark. July is a great time in Washington to enjoy the beautiful mountains and beaches, with clear skies for clicking pictures. Expect crowds at all attractions, and plan for accommodations.
Weather in August
August is a warm summer month in Washington with beautiful weather and light rain. The Pacific coast swarms with visitors from all over the state and the country to enjoy the warm waters. Temperatures average between 50°F (10°C) to 73°F (22.8°C) but vary considerably by altitude and region. The Cascade Mountains region offers cool nights with average low temperatures in the 45°F (7.2°C) to 50°F (10°C) range. A small area east of the Columbia River sees relatively warmer temperatures that cross 100°F (37.8°C). Mount Baker is a popular tourist destination with scenic views and clear skies during the summer. August sees 20 to 25 sunny days, which are perfect for biking, hiking, fishing, and swimming. Campgrounds rarely remain vacant in the spectacular Mount Rainier National Park as the days are comfortable and the nights are cozy. The green landscape with snow-capped mountains in the distance is one of the highlights of mid-summer. Expect an odd thunderstorm in the highlands. Light summer clothing adds to the comfort of the August days in Washington.
Weather in September
September brings the colorful autumn season to Washington with warm temperatures amid a slight uptick in rainfall. The Pacific Coast sees 2" (50.8mm) to 4" (101.6mm) of rain, while the average precipitation in the state is a moderate 2" (50.8mm). The average high temperatures are in the ideal 65°F (18.3°C) to 75°F (23.9°C) range, while the nights are relatively cooler in the average low-temperature range of 40°F (4.4°C) to 50°F (10°C). The skies are partly cloudy, with an average of 16 to 18 sunny days statewide. Fall is the best time to visit Wenatchee, with bustling orchards and farms that export more apples than anywhere else in the world. The leaves begin to change colors by mid-September as the beautiful autumn is evident in the atmosphere. It is routine to encounter wildlife in the natural preserves during the fall nights and mornings. Pack warm clothes for breezy evenings and cold nights. Expect temperatures to drop with each passing day in September in Washington.
Weather in October
October is the time of peak fall foliage in Washington as the wet season beings in the state. Aspens, maples, larches, and many other trees display brilliant shades of red, orange, yellow, gold, and purple. Washington is one of the best places in the United States for fall visits, with its broad palette of colors in the backdrop of panoramic mountains. The average high temperatures are in the warm range of 52°F (11.1°C) to 62°F (16.7°C), while average low temperatures register in the cold 32°F (0°C) to 42°F (5.6°C). The skies are partly cloudy as the sunshine is moderate, and the breezy wind adds to the joy of driving through the scenic byways. The harvest season is underway, and there is scarcely another period in the year with abundant food, fruits, and wine. Days gradually become shorter by the end of October in Washington, with even a few incidences of snow. A light sweater or a rain jacket is handy as the temperatures drop sharply after sunset.
Weather in November
November sees cold weather in Washington as the autumn season wanes steadily. The temperatures are in the average range of 30°F (-1.1°C) to 43°F (6.1°C) in the state. Spokane in the east averages between 30°F (-1.1°C) to 42°F (5.6°C), while Grayland in the west is between 40°F (4.4°C) to 53°F (11.7°C). Late fall brings significant precipitation that averages 6.2" (157.5mm) in the state. The west coast and the Cascades region see 15" (381mm) to 20" (508mm) of rainfall, while Puget Sound receives between 5" (127mm) to 7" (177.8mm). The first snowfall of the season occurs in many areas, with an average of 10" (254mm) in Leavenworth and a massive 120" (3048mm) in Mount Rainier. The skies are mostly cloudy, with 6 to 8 sunny days in the month. High Mountain trails close by November end as rain and snowfall pick up considerably. Pack in layers as the nights are occasionally freezing, and the evenings are cold. Budget travelers find November reasonable with fair weather and cheap accommodations in Washington as the crowds dwindle.
Weather in December
December is the wettest month of the year in Washington with an average of 6.5" (165.1mm) of rainfall in the state. The winter is severely cold, with gray skies, ample rain, and abundant snow. The average high temperatures are in the 31°F (-0.6°C) to 41°F (5°C) range, and the average low temperatures are in the 20°F (-6.7°C) to 30°F (-1.1°C) zone. Winthrop is one of the coldest places in the eastern part, with average temperatures in the 14°F (-10°C) to 29°F (-1.7°C) zone. The coastal regions are warmer than the rest due to proximity to the Pacific Ocean. Lower slopes of the Cascade Mountains record 15" (381mm) to 20" (508mm) of snowfall, while higher ones report 100" (2540mm) and above. Sunny days are few and far between, with mild sunshine at the most. Long Beach sees few tourists with 12" (304.8mm) of rainfall. However, the snow depth makes skiing one of the most popular activities in December in Washington. Expect the cold and precipitation to last for long periods.