Last updated: January 18, 2025
The climate of Washington, United States, exhibits a diverse range of conditions, categorized mainly under the Koppen-Geiger climate classes: Csb, Cfb, Csa, Dsb, Dfb, and BSk. This variety results in significant temperature fluctuations, with recorded extremes ranging from a chilling minimum of –30°C (–21°F) in February to a scorching maximum of 48°C (119°F) in June. Overall, the average annual temperature hovers around a mild 11°C (51°F), illustrating the state's unique climatic characteristics that cater to a wide range of ecosystems and seasonal activities.
Washington, United States, reveals a striking seasonal temperature pattern, characterized by sharp contrasts between winter's chill and summer's warmth. In the winter months, particularly January and February, temperatures plummet, with lows reaching as low as –30°C (–21°F) and averaging around 3°C (37°F). As spring approaches, temperatures gradually rise, with March and April witnessing a notable uplift, peaking at a mild average of 9°C (49°F) in April. The transition into summer brings significant warmth, exemplified by extraordinary highs in June reaching 48°C (119°F), before settling into the consistently warm averages of July and August around 20°C (68°F). Autumn heralds a return to cooler conditions, with September showing a maximum of 40°C (104°F) followed by the gradual cooling into the winter months, reinforcing the cyclical dance of Washington's diverse climate.
Chelan experiences a wide range of temperatures throughout the year, from a chilly minimum of -19°C (-1°F) in December to a scorching maximum of 43°C (109°F) in June. For more detailed information, you can explore the monthly temperature in Chelan. Similarly, Leavenworth endures harsh winters with temperatures plummeting to -22°C (-6°F) in December, and summers can heat up to 37°C (98°F) in June. Discover more about the monthly temperature in Leavenworth. Seattle's climate is characterized by milder winters, with the lowest temperatures reaching -10°C (14°F) in February, and warm summers peaking at 38°C (101°F) in June. For a comprehensive overview, check the monthly temperature in Seattle.
Washington experiences a dynamic pattern of precipitation throughout the year, with the wettest months occurring in winter. January and December are particularly notable, with precipitation levels reaching 168 mm (6.6 in) and 183 mm (7.2 in), respectively. February follows closely behind, contributing 163 mm (6.4 in) as the region is characterized by frequent rainy days, averaging between 15 to 17 days of precipitation. As spring approaches, precipitation begins to taper off, with March and April showing decreases to 122 mm (4.8 in) and 106 mm (4.2 in).
The summer months witness a significant dip in rainfall, particularly in July and August, where only 17 mm (0.7 in) is recorded for each month. This dry season is characterized by just a few rainy days, averaging only three. As fall sets in, precipitation begins to rise again, peaking in October with 139 mm (5.5 in) and continuing into November, which sees 178 mm (7.0 in). This seasonal variability in rainfall contributes to the unique ecosystems and climates found throughout the state, showcasing Washington's rich environmental diversity.
In Washington, the sunshine duration reveals a clear seasonal trajectory, marked by significant variations from winter through summer. The year begins under a veil of cloudiness, with January receiving just 86 hours of sunshine, which gradually increases to 133 hours by February. March sees a notable rise to 210 hours, as the promise of spring emerges. This upward trend continues throughout spring, peaking in May with 316 hours, signaling the onset of longer days and more consistent sunshine as residents welcome the warming climate.
The summer months bring the highest sunshine duration, especially in July, where Washington basks in an impressive 380 hours of sunlight. However, as August rolls in, the days begin to shorten, resulting in 341 hours of sunshine. Fall introduces a decrease, with September still enjoying a wholesome 266 hours before the dreariness of November settles in with 129 hours. By December, sunshine dips further to just 103 hours. This seasonal pattern not only highlights the region's vibrant summer but also the stark contrast of varying daylight hours that influence the state's climate and the lifestyle of its residents throughout the year.
The ultraviolet (UV) index in Washington showcases a significant seasonal variation, emphasizing the importance of sun protection during certain months. Beginning in January, the UV index is relatively low at 2, but it ramps up steadily as spring approaches, reaching a moderate level of 6 by March. April marks a notable increase, with levels climbing to 8, and by May, the UV index peaks at 10. This trend of heightened UV exposure continues into the summer months of June and July, where Washington experiences consistent UV levels of 10, highlighting the need for sun safety during outdoor activities.
As summer wanes, the UV index begins to decline, although it remains considerable in August at 9. Moving into fall, Washingtonians can expect lower UV levels, with September showing a drop to 8 and October further reducing to 5. By November and December, the UV index returns to its winter baseline of 3 and 2, respectively. Understanding these trends is crucial for residents and visitors alike, as they indicate the varying risks of UV radiation throughout the year and the essential practices for skin protection.
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In Washington, the duration of daylight fluctuates significantly throughout the year, reflecting the changing seasons and the tilt of the Earth's axis. January begins the year with a modest 8 hours of daylight, slowly increasing to 10 hours in February as the days gradually lengthen. March sees further growth to 11 hours, signaling the approach of spring. This upward trend accelerates dramatically in April, where daylight stretches to 13 hours, and continues into May, offering a generous 15 hours. The summer months of June and July maintain this peak of 15 hours, allowing for plenty of outdoor activities under long, sunny days.
As summer transitions to fall, daylight begins to wane, with August dropping slightly to 14 hours and September further reducing to 12 hours. The descent continues into October, which exhibits only 10 hours, followed by November with 9 hours, as the onset of winter becomes increasingly prominent. By December, daylight returns to the lowest point of the year at 8 hours. This cyclical pattern not only has implications for daily life and activities in Washington but also serves as a reminder of nature's rhythmic changes through the seasons.
Bainbridge Island, located in Washington state, experiences a temperate climate characterized by mild, wet winters and warm, dry summers. Winter temperatures average around 6°C (43°F) in December and January, with highs occasionally reaching 14°C (57°F), while precipitation is significant, peaking at 179 mm (7.1 in) in December. In contrast, the summer months bring warmer and drier conditions, with average temperatures reaching 19°C (67°F) in July and August, and rainfall dropping to just 26 mm (1.0 in). Sunshine varies throughout the year, peaking during summer with 361 hours in July and tapering off to 80 hours in January. For more detailed information on the Bainbridge Island climate.
Located in the United States, Birch Bay experiences a varied climate with distinct seasonal changes. Winter months are cold, with temperatures dropping to -13°C (9°F) in December and significant precipitation, peaking at 296 mm (11.7 in) in November. Spring and autumn bring moderate temperatures, with March and October seeing average temperatures around 7°C (45°F) and 10°C (51°F) respectively. Summers are warm and relatively dry, with July's average temperature reaching 18°C (66°F) and minimal rainfall of around 28 mm (1.1 in). Sunshine is abundant in summer, culminating at 387 hours in July, in contrast to the 83 hours in January. For more details, refer to the Birch Bay climate page.
Chelan, located in Washington, experiences significant temperature fluctuations throughout the year. Winters are cold with January averaging -2°C (28°F) and temperatures dropping as low as -17°C (1°F), while summers are warm with July seeing highs of 40°C (105°F). Precipitation is moderate, starting with 76 mm (3.0 in) in January and tapering off to just 2 mm (0.1 in) in July, the driest month, before picking up again in the fall. The area enjoys ample sunshine, particularly during summer months, with July offering 416 hours of sunlight. For more detailed climate information, visit Chelan climate.
Coulee Dam in the United States experiences a varied climate characterized by cold winters and hot summers. January tends to be the coldest month with temperatures ranging from -24°C (-11°F) to 9°C (49°F), while July is the warmest, with temperatures peaking at 41°C (107°F). Precipitation is relatively moderate, with January and December being the wettest months, receiving 67 mm (2.6 in) and 57 mm (2.2 in) respectively, while June and July are driest, with only 13 mm (0.5 in) and 4 mm (0.1 in) of rainfall. Sunshine hours peak in July with 418 hours, providing abundant daylight and warmth. More detailed information about the climate in Coulee Dam can be found here.
Forks, United States, experiences a varied climate with cool, wet winters and mild, drier summers. Winter months, particularly November and December, receive significant rainfall, peaking at 336 mm in November, while the summer months of July and August see considerably less, at 23 mm and 25 mm respectively. Temperatures range from minimums of -4°C in December to highs reaching 34°C in June. Sunshine hours are limited during winter, but increase significantly from May to August, with July offering the most sunshine at 339 hours. For more detailed climate information, visit Forks climate.
Friday Harbor, located in the United States, experiences a mild maritime climate with relatively stable temperatures throughout the year. Winters are cool with January and February having average lows of -3°C (27°F) and average highs of 11°C (52°F), while summers are mild, featuring average highs of around 20°C (68°F) in the months of June through August. The area receives substantial rainfall from October to March, peaking in November with 194 mm (7.6 in), but the summer months are much drier, with July and August seeing as little as 15 mm (0.6 in) of rain. Sunshine hours are notably higher from April to September, with July being the sunniest month with 390 hours of sunshine. For more detailed information, visit Friday Harbor climate.
Leavenworth, located in the United States, experiences a highly varied climate with cold winters and warm summers. Winter months, particularly from December to February, see temperatures ranging from -21°C to 11°C (-6°F to 52°F) with significant precipitation peaking in December and February at approximately 151 mm (6.0 in). During summer, July and August are the driest and warmest, with temperatures climbing to 34°C (93°F) and minimal rainfall of merely 6 mm (0.2 in). Sunshine hours peak in July at 410 hours, while winter months receive considerably less sunshine, such as January with 88 hours. For further details, you can visit Leavenworth climate.
Long Beach, United States, experiences mild temperatures throughout the year, with average highs ranging from 13°C (56°F) in winter months to about 25°C (77°F) in summer. Winters are marked by significant precipitation, peaking in December and January with over 240 mm (approximately 9.8 inches) of rainfall, while July and August are notably drier. Sunshine hours progressively increase from winter to summer, reaching a peak of 358 hours in July before decreasing toward the year's end. The climate in Long Beach offers a balanced mix of rainfall and sunshine, supporting a thriving ecosystem and diverse outdoor activities year-round. For more detailed information, visit the Long Beach climate page.
Ocean Shores experiences a mild and varied climate throughout the year, characterized by cool winters and warm summers. Winter months, such as January and December, see temperatures ranging from 0°C (32°F) to 13°C (56°F) with high precipitation levels, peaking at 280 mm (11.0 in) in January. Spring brings gradual warming, averaging 8°C (46°F) to 14°C (57°F) from March to June, accompanied by decreasing rainfall and increasing sunshine, reaching 316 hours in June. Ocean Shores climate achieves its warmest temperatures in July and August, with highs around 23°C (73°F) and minimal rain. Autumn sees a return of cooler and wetter conditions, with October and November bringing significant rainfall and decreased sunshine hours.
Olympia, United States, experiences a diverse climate with mild winters and warm to hot summers. Winter months from December to February see average temperatures around 5°C (41°F) with considerable rainfall, peaking in December at 203 mm (8.0 in). As spring progresses, the temperature rises, culminating in June with highs reaching up to 40°C (104°F), though rainfall significantly decreases to just 51 mm (2.0 in) in June. During summer, July and August are the driest months, featuring maximum temperatures of 33°C (92°F) and 34°C (93°F), complemented by abundant sunshine with July enjoying 362 hours of sunlight. As autumn sets in, temperatures gradually decline, and precipitation increases, with November experiencing 192 mm (7.5 in) of rainfall. For more detailed information, visit the Olympia climate.
The climate in Palouse, United States, is characterized by cold winters and hot summers. Winter months like December and January see temperatures plummet to as low as -19°C (-2°F) with significant precipitation, reaching up to 105 mm (4.1 in) in February. As spring arrives, temperatures gradually rise, peaking in July with averages around 23°C (73°F) and highs of up to 40°C (104°F), while summer remains dry, particularly in July with just 5 mm (0.2 in) of rain. Sunshine is abundant during the summer, with July boasting 412 hours, contrasting sharply with the 100 hours seen in January. More detailed information can be found on the Palouse climate page.
Port Angeles, located in Washington, experiences a diverse climate with distinct seasonal changes. Winters are cold with temperatures ranging from -14°C (7°F) in February to a mild 10°C (50°F) in December, accompanied by high precipitation, notably 246 mm (9.7 in) in November. Summers present milder temperatures, peaking at 32°C (90°F) in June, with significantly reduced rainfall averaging just 27 mm (1.1 in) in July and August. The city enjoys substantial sunshine during summer months, particularly in July with 375 hours, contrasting with the darker winter months like December which has only 99 hours of sunlight. For more detailed information, visit Port Angeles climate.
Port Angeles East exhibits a diverse climate characterized by cool winters and mild summers. During winter months, average temperatures hover around 2°C (36°F) and can drop as low as -14°C (7°F), coupled with high precipitation of up to 211 mm (8.3 in) in November. The summer months bring milder weather, with July and August averaging 15-16°C (58-60°F) and experiencing minimal rainfall of around 37-39 mm (1.5 in). The region enjoys abundant sunshine, reaching its peak in July with 382 hours. For more detailed information, visit the Port Angeles East climate.
Port Townsend, located in Washington, United States, experiences a maritime climate with mild and relatively wet weather year-round. Winters are cool with average temperatures ranging from 6°C (43°F) in January to a high of 13°C (55°F) in December, accompanied by substantial precipitation levels, peaking at 187 mm (7.4 in) in both November and December. Summers are mild and drier, with average temperatures reaching their zenith in July and August at 17°C (63°F), complemented by significantly lower rainfall around 58 mm (2.3 in) in July. The region enjoys a considerable increase in sunshine during the summer months, peaking at 382 hours in July, offering a beautiful contrast to the dimmer winter months. For more detailed information, please refer to the Port Townsend climate.
Rainier, located in the United States, experiences a diverse climate characterized by cold winters and warm summers. Winter months from December to February see average temperatures around 5°C (42°F) with significant precipitation ranging from 163 mm to 199 mm, accompanied by limited sunshine, notably only 81 hours in January. The warmer months of June to August bring average temperatures up to 19°C (66°F) and reduced rainfall, particularly in July with just 10 mm, alongside abundant sunshine, reaching up to 364 hours in July. Transition seasons such as March-May and September-November show a steady rise and fall in temperatures and daylight hours, with moderate precipitation. For more detailed information, visit the Rainier climate.
Seattle's climate features mild, wet winters and warm, relatively dry summers, creating a distinctive seasonal contrast. Winter months are marked by average temperatures ranging from 6°C (43°F) in January to 8°C (47°F) in November, with December seeing the highest precipitation at 196 mm (7.7 in). As spring progresses, temperatures gradually rise, reaching a summer average high of 19°C (67°F) in July and August, when the city records its lowest rainfall, with only 18 mm (0.7 in) and 16 mm (0.6 in), respectively. Summer is the sunniest period with up to 361 hours of sunshine in July, contrasting with the gloomier December, which experiences just 93 hours of sunshine. For more details, visit the Seattle climate.
The climate in Snoqualmie, United States, is characterized by cold winters and mild to warm summers. January and February are the coldest months, with average temperatures around 2°C (36°F) and considerable precipitation, averaging around 240 mm to 296 mm (9.4 in to 11.6 in). Summer months bring warmer temperatures, with July and August reaching average highs of 32°C (89°F) and 34°C (94°F) respectively, and precipitation significantly reduces to around 29 mm to 38 mm (1.1 in to 1.5 in). Sunshine hours peak in July at 357 hours, indicating more sunny days during summer. For more details, visit the Snoqualmie climate.
Walla Walla experiences a diverse climate with cold winters and hot summers. In the winter months, temperatures can drop to a minimum of -19°C (-1°F) in January, while summer temperatures can soar to a maximum of 43°C (110°F) in June. Precipitation varies significantly throughout the year, with February witnessing the highest rainfall at 125 mm (4.9 in) and July experiencing minimal rainfall at just 2 mm (0.1 in). The region enjoys ample sunshine, especially in July, which sees the most sunny hours at 411. For more detailed climate information, you can visit the Walla Walla climate page.
Westport, United States, experiences a varied climate throughout the year, with temperatures ranging from chilly winters, where January sees an average low of -5°C (24°F) to mild summers peaking in June at a maximum of 40°C (104°F). Precipitation is highest during the winter months, notably in November with 267 mm (10.5 in) and January with 259 mm (10.2 in), while July and August are relatively dry with only about 13 mm (0.5 in). Sunshine hours increase significantly in the summer, with July experiencing the longest days at 359 hours of sunlight, contrasting with shorter days in December and January. For more details about Westport's weather patterns, visit the Westport climate.
In conclusion, Washington State's climate, characterized by its diverse temperature ranges, seasonal variations in precipitation, UV index, sunshine duration, and daylight hours, showcases the intricate interplay of natural elements that shape the region's environment. From the frigid winter months with minimal daylight and reduced UV exposure to the sun-drenched summers that offer ample outdoor time and higher UV risks, understanding these patterns is essential for both residents and visitors. This knowledge not only facilitates better planning for activities throughout the year but also emphasizes the importance of taking appropriate sun safety measures during peak UV periods. As Washington continues to experience changes in its climate, awareness of these dynamics remains crucial for healthy and enjoyable engagement with the state's rich natural beauty.