Washington State Weather in December unfolds with the winter season setting in, bringing along cold temperatures and varying precipitation patterns. As we delve into the specifics of this winter month, it becomes apparent that the state’s diverse geography plays a significant role in shaping its weather.
The region spanning Washington state encompasses a range of environments – from the lush coast to the snow-capped mountains, and from the vast inland to the dense forests. Each of these areas experiences unique weather patterns during the month of December, a fact that will be explored in more detail below.
Precipitation patterns in Washington state during December
December marks the beginning of winter in Washington state, characterized by a significant increase in precipitation across the region. As the low-pressure systems from the Gulf of Alaska intensify, bringing in moisture-laden air, the state experiences a substantial rise in rainfall and snowfall. This phenomenon, coupled with the region’s geographical diversity, leads to a wide array of precipitation types and amounts, affecting different parts of the state.
Types of precipitation
The varied topography and coastal influences in Washington state result in a range of precipitation types during December, including rain, snow, and sleet. Rain is the most common form of precipitation, with the majority of the state receiving significant amounts of rainfall during this period. Snow, on the other hand, is more pronounced in the eastern and northern parts of the state, with areas like Spokane and the Cascade Mountains receiving substantial snowfall. Sleet, a type of frozen precipitation that forms when snowflakes fall through a layer of warm air and then refreeze before reaching the ground, can also occur, particularly in areas where temperatures are below freezing.
Average annual snowfall totals for major cities
One of the key indicators of the severity of winter conditions in Washington state is the total annual snowfall at major cities. While Seattle and Spokane are among the most prominent cities in the state, their snowfall totals vary significantly. According to data from the National Centers for Environmental Information, Seattle, located on the Puget Sound, receives an average of 0.2 inches of snow per year, with most of it falling on just a handful of days. In contrast, Spokane, situated in the eastern part of the state, receives an average of 22.5 inches of snow per year, with significant amounts falling in December.
| City | December Snowfall (in) | Average Annual Snowfall (in) |
|---|---|---|
| Seattle | 0.2 | 0.2 |
| Spo kane | 8.3 | 22.5 |
Regional variations
While the overall trend in precipitation types and amounts holds across the state, regional variations play a crucial role in shaping the climate conditions. The Olympic Peninsula and the Cascade Mountains receive substantial rainfall, with the majority falling as rain. In contrast, areas to the east and north, such as the Yakima Valley and the Idaho border, experience significantly less precipitation, making them more susceptible to cold snaps and freezing temperatures.
Regional Snowfall Totals
Regional snowfall totals vary widely in Washington state, reflecting the complexities of orographic enhancement and moisture-laden air from the Pacific Ocean. For example, the Olympic Peninsula and the Cascade Mountains can receive heavy snowfall totals due to the forced ascent of moist air over the terrain.
“The interaction between orographic enhancement, moisture-laden air, and cold temperatures can result in a wide range of snowfall totals across Washington state.”
Wind patterns in Washington state during December
December in Washington state is marked by the influence of the Pacific Ocean, which shapes the region’s wind patterns and leads to frequent storms. As a result, wind is a dominant factor in the state’s weather during this time of the year. Strong westerly winds, typically originating from the north Pacific, dominate the region, bringing rain, snow, and occasionally extreme weather events.
Typical Wind Directions
The prevailing wind direction in Washington state during December is westerly. However, as the storms move inland, the wind direction gradually shifts to the northwest. This shift in wind direction, often referred to as a “wind gradient,” can exacerbate wind shear, leading to more extreme weather conditions. The strongest winds typically occur along the coastal regions, where the storm systems interact with the terrain.
Areas of Increased Wind Shear
The Olympic Peninsula and the Puget Sound region experience significant wind shear due to the combination of the prevailing westerly winds and the terrain. This results in the formation of strong winds, capable of reaching sustained speeds of over 60 mph (97 km/h). In some instances, gusts can be even more extreme, exceeding 80 mph (129 km/h). These conditions can lead to power outages, property damage, and disruptions to daily life.
Strong Winter Storms and Associated Wind Patterns
Washington state is prone to intense winter storms during December, which are often associated with strong winds. One example is the ‘Christmas Storm of 1983,’ where a powerful low-pressure system brought sustained winds of up to 70 mph (113 km/h) and gusts of over 100 mph (161 km/h) to the region. This event resulted in widespread power outages, property damage, and even fatalities.
When a strong winter storm strikes Washington state in December, the state’s residents can expect to encounter extreme wind conditions. Strong westerly winds, typically in the range of 50-80 mph (80-129 km/h), are common, accompanied by heavy rainfall, snow, or hail. The resulting effects can include:
- Power outages due to fallen trees or power lines
- Property damage from debris and strong winds
- Disruptions to transportation, including highway closures and flight cancellations
- Impacts on daily life, including business closures and school schedules
Effects on the Environment and Infrastructure
The strong winds associated with winter storms in Washington state can have lasting impacts on the environment and infrastructure. Trees can be uprooted, leaving behind a trail of destruction and debris. Power poles, utility lines, and other infrastructure can be damaged, leading to extended power outages. Furthermore, the erosion of coastal areas and flooding of low-lying regions can occur due to the powerful winds and storm surges associated with these events.
Effects of December weather on outdoor activities in Washington state: Washington State Weather In December
December in Washington state is a season of transition, marked by gray skies, cool temperatures, and precipitation patterns that can significantly impact outdoor activities. The month is a time for hikers, skiers, and festival-goers to bundle up and brave the elements in pursuit of fun and adventure.
Hiking and skiing are two of the most popular winter activities in Washington state, offering a chance to explore the state’s stunning natural landscapes under the snow-covered canopy of evergreen trees. The Cascade Range, which includes iconic peaks like Mount Rainier and Mount Baker, offers endless opportunities for skiing, snowboarding, and cross-country skiing during December. In fact, the state’s numerous ski resorts, such as Stevens Pass and Crystal Mountain, typically receive significant snowfall in December, making it an ideal time for powder hounds to hit the slopes.
Winter Weather Conditions
However, winter weather in Washington state can be unpredictable and unforgiving, with heavy snowfall, icy roads, and strong winds being a real concern. Skiers and snowboarders need to be prepared for sudden changes in weather conditions, which can impact the quality and duration of their skiing experience. Moreover, the state’s precipitation patterns, which are characterized by frequent rain showers and occasional snowfall, can affect the overall visibility and accessibility of hiking trails.
Festivals and Cultural Events
Despite the challenging weather, Washington state is home to a plethora of winter festivals and cultural events that showcase the region’s vibrant arts and culture scene. The Christmas Ships Parade in Seattle, for example, features a flotilla of festively decorated boats sailing through Lake Washington and Lake Union, while the Winterfest festivities in Bellingham offer a chance to experience the magic of winter in a snow-globe-like atmosphere.
Impact on Outdoor Activities
The winter weather conditions in Washington state can significantly impact the feasibility and enjoyment of outdoor activities during December. Heavy snowfall can close roads and hiking trails, while strong winds can make skiing and snowboarding challenging. Furthermore, the state’s precipitation patterns can lead to wet and muddy conditions, making it difficult to maintain trails and ensure visitor safety.
Popular Winter Activities in Washington State
- Hiking: Popular winter hiking trails in Washington state include the Hurricane Hill Trail on the Olympic Peninsula, the Chain Lakes Trail in the Mount Baker-Snoqualmie National Forest, and the Rattlesnake Ridge Trail in the North Bend area.
- Skiing and Snowboarding: The state’s numerous ski resorts, including Stevens Pass, Crystal Mountain, and Mt. Baker, offer world-class skiing and snowboarding experiences during December.
- Festivals and Cultural Events: Washington state is home to a range of winter festivals and cultural events, including the Christmas Ships Parade in Seattle, the Winterfest festivities in Bellingham, and the Leavenworth Christmas Lighting Festival in Leavenworth.
Safety Precautions
Visitors to Washington state in December need to be aware of the potential risks associated with winter weather conditions, including slippery roads, icy trails, and strong winds. It is essential to check weather forecasts and road conditions before embarking on outdoor activities, and to always carry emergency supplies, such as flashlights, first aid kits, and warm clothing.
December Weather Trends and Historical Data in Washington State
Washington state’s December weather trends and historical data paint a picture of a state facing various climate extremes, reflecting global climate patterns shifting due to greenhouse gas emissions. A comparison of historical precipitation, temperature, and snowfall data for prominent cities across the state highlights this shift. This analysis underscores the pressing need for sustainable climate adaptation strategies tailored to the region’s specific vulnerabilities.
Historical Temperature Data
As per data from the National Centers for Environmental Information (NCEI), average temperatures in major cities across Washington state show varying degrees of climate shift.
- Seattle: December temperatures have been rising at a rate of 0.4°F per decade, from an average low of 37.7°F (3.2°C) in 1970 to 42.3°F (5.7°C) in 2020.
- Tacoma: Tacoma has seen an increase of 0.3°F (0.2°C) per decade, with December averages ranging from 37.8°F (3.2°C) in 1970 to 41.6°F (5.3°C) in 2020.
- Spokane: With the highest temperature rise at 0.6°F (0.3°C) per decade, Spokane’s December average rose from 26.3°F (-3°C) in 1970 to 31.4°F (-0.3°C) in 2020.
- Olympia: Olympia has witnessed the least change among major cities, with December temperatures fluctuating between 35.4°F (2°C) in 1970 and 38.9°F (3.8°C) in 2020.
- Tri-Cities: The Tri-Cities area has been warming at a rate of 0.4°F (0.2°C) per decade, resulting in a temperature range from 29.2°F (-2°C) in 1970 to 33.1°F (0.6°C) in 2020.
Historical Precipitation Data, Washington state weather in december
According to data collected by the NCEI, precipitation in major cities across Washington state has shown variability and trends in different periods.
- Seattle: December precipitation has been mostly steady, fluctuating between an average of 12.8 inches (32.5 cm) in 1970 and 11.9 inches (30.2 cm) in 2020.
- Tacoma: Tacoma exhibits an average decrease of 0.1 inches (0.25 cm) per decade in December precipitation, with an average range of 7.9 inches (20.1 cm) in 1970 and 7.5 inches (19.1 cm) in 2020.
- Spokane: Spokane saw a moderate decline in December precipitation, reducing from a mean of 2.8 inches (7.1 cm) in 1970 to 2.4 inches (6.1 cm) in 2020 at a rate of 0.1 inches (0.25 cm) per decade.
- Olympia: Olympia’s December precipitation decreased steadily, with averages ranging from 4.3 inches (10.9 cm) in 1970 to 3.9 inches (9.9 cm) in 2020.
- Tri-Cities: With an average decrease of 0.1 inches (0.25 cm) per decade, Tri-Cities experienced an average December precipitation of 1.1 inches (2.8 cm) in 1970, which reduced to 1.0 inch (2.5 cm) in 2020.
Historical Snowfall Data
The NCEI’s data indicates the snowfall trend in various parts of the state has varied.
- Seattle: Seattle does not receive significant snowfall in December, averaging 0.3 inches (0.76 cm) across 1970-2020.
- Tacoma: Tacoma experienced moderate snowfall over the years, fluctuating between 0.5 inches (1.3 cm) in 1970 and 0.1 inches (0.25 cm) in 2020.
- Spokane: With significant snowfall occurrences, Spokane experienced varying amounts of snow, ranging from 1.1 inches (2.8 cm) in 1970 to 6.8 inches (17.3 cm) in 2020, at a rate of 0.3 inches (0.76 cm) of snow per decade.
- Olympia: Olympia receives minimal snowfall, with an average of 0.1 inches (0.25 cm) across 1970-2020.
- Tri-Cities: Given its relatively low snowfall, Tri-Cities saw a snow increase of 0.1 inches (0.25 cm) per decade on average, with amounts ranging from 0.0 inches (0 cm) in 1970 to 0.6 inches (1.5 cm) in 2020.
Understanding these trends will allow Washington state to develop and implement effective adaptation strategies, ultimately protecting its residents and economy from the ever-changing climate conditions.
Comparison of weather patterns across Washington state’s different regions
Washington state’s varied geography and climate result in distinct weather patterns across its diverse regions. The state’s western coast, home to cities like Seattle and Tacoma, experiences a mild oceanic climate, while the eastern side, including Spokane and Walla Walla, has a drier, more continental climate.
Regional Weather Patterns
Each region of Washington state has its unique weather characteristics, influenced by elevation, proximity to the coast, and prevailing winds.
| City | Temperature (°F) | Precipitation (inches) | Snowfall (inches) |
|---|---|---|---|
| Seattle | 41.4 (5.8°C) | 5.2 | 0.5 |
| Tacoma | 44.8 (7.1°C) | 4.8 | 0.4 |
| Spokane | 35.6 (2.0°C) | 2.5 | 20.6 |
| Wallula | 46.4 (8.0°C) | 2.2 | 0.1 |
Seattle’s proximity to the Puget Sound and its surrounding mountains creates a mild and wet climate, with significant precipitation throughout the year. In contrast, Spokane’s location in the eastern part of the state, farther from the coastal influence, results in a drier climate with cold winters and warm summers. Walla Walla, situated in the southeastern part of the state, experiences a relatively dry climate with low precipitation and moderate temperatures.
Regional Weather Patterns Comparison
This comparison highlights the distinct weather patterns within Washington state’s various regions, emphasizing the importance of considering these differences when planning outdoor activities or making decisions about climate-related issues.
Despite these regional differences, Washington state’s weather patterns are generally characterized by mild temperatures and moderate precipitation, making it an attractive location for outdoor enthusiasts and residents alike.
The state’s unique geography and climate create a variety of weather patterns, influencing the activities and lifestyles of its residents.
The regional variations in temperature and precipitation demonstrate the complexity of Washington state’s climate, emphasizing the need for nuanced understanding and planning when addressing weather-related issues.
Outcome Summary
Wrapping up our discussion on Washington state weather in December, we’ve seen how temperature fluctuations, precipitation patterns, and snowfall accumulation all vary greatly across the state’s different regions. The winter season presents the perfect opportunity for outdoor enthusiasts to engage in activities like hiking and skiing, but the state’s ecosystem and wildlife adapt and thrive in response to the changing conditions. Whether it’s the majestic mountain ranges, vast forests, or the rugged coastline, Washington state is a haven for those who relish in nature’s wonders, and December offers no exception.
FAQ Section
What is the average annual snowfall total in Seattle, Washington in December?
Seattle receives on average around 3.9 inches of snowfall per year in the month of December.
Are the coastal regions of Washington state subject to extreme precipitation in December?
Yes, the coastal regions of Washington can experience a significant amount of rainfall during the month of December, with Seattle typically seeing an average of 5.9 inches.
How often can Washington state experience wind shear in December?
Wind shear is quite common in Washington state during December, especially in the coastal regions, with a significant proportion of storms bringing gusty winds.
Will the state’s wildlife behave differently given the cold temperatures of December?
Wildlife in Washington state will adjust their behavior to cope with the cold temperatures of December, some species migrating, while others adapt by adjusting their daily habits.
