Last updated: February 24, 2025
December in Walla Walla, United States ushers in a chilly embrace, with temperatures ranging from a brisk -14°C (6°F) to a milder 18°C (65°F). The average temperature hovers around 1°C (34°F), bringing a crispness that characterizes the month. As winter settles in, the region experiences 93 mm (3.7 in) of precipitation over 15 days, contributing to the 87% humidity that cloaks the area. This blend of cold temperatures and moisture creates a stunning, frosty landscape, perfect for enjoying seasonal activities.
In December, Walla Walla experiences a distinct chill as winter firmly sets in. With minimum temperatures dipping to -14°C (6°F) and the average hovering around 1°C (34°F), the month marks a notable transition from the milder conditions of fall. Daytime highs can reach up to 18°C (65°F), but this warmth feels fleeting in the embrace of the colder nights. Comparing December's figures to the preceding months, a trend towards cooler temperatures is evident, as the region moves from the relatively mild averages of November into the depths of winter. This blend of brisk air and occasional daytime warmth creates a wintry atmosphere that embodies the season's charm, inviting residents and visitors alike to enjoy cozy gatherings and holiday festivities.
In December, Walla Walla experiences a notable uptick in precipitation, with an average of 93 mm (3.7 in) over approximately 15 days of rainfall. This marks a significant increase compared to the drier summer months, where July and August receive negligible amounts. As autumn transitions into winter, December's precipitation showcases a stark shift, aligning closely with November's totals of 84 mm (3.3 in) and establishing a trend of heightened moisture as the year draws to a close. This consistent rainfall is essential for replenishing local water sources and nurturing the region's agricultural landscape, setting the stage for a fresh start in the coming year.
As December arrives in Walla Walla, a notable rise in humidity is observed, peaking at 87%. This marks a slight increase from November's 85%, continuing the trend of elevated moisture levels typical during the winter months. Throughout the year, humidity slowly declines from its January and February highs of 86%, hitting its lowest point in August at 60%. However, as the seasons shift back towards winter, humidity levels rise again, suggesting a cycle of fluctuating moisture that accompanies the changing weather patterns in this charming region. Overall, December signifies a return to the dampness typical of the colder months, inviting cozy indoor gatherings while the crisp air outside is laden with moisture.
In December, Walla Walla experiences a low UV Index of 2, making it one of the safer months for sun exposure. With a burn time of 45 minutes, residents and visitors alike can enjoy the outdoors with minimal risk of skin damage. This trend of lower UV levels is a sharp contrast to the heights seen during the summer months, where values peaked at 10 in June and July, indicating a very high exposure risk with burn times slashed to just 15 minutes. As the year progresses from the intense summer sun to December's gentle rays, the gradual decrease in the UV Index highlights the importance of seasonal awareness for skin protection. For more details on the UV Index throughout the year, check out Walla Walla UV Index.
UV Risk Categories
In Walla Walla, December welcomes a gentle embrace of 141 sunshine hours, signifying a notable decline from the summer highs of 411 hours in July. As the year winds down, the sun's presence diminishes, yet the light remains bright enough to hint at the approaching joy of the holiday season. Following a pattern that mirrors the transition from autumn to winter, December's sunshine hours showcase a comforting stability when compared to November's 177 hours, suggesting a serene end to the year. As the days grow shorter, Walla Walla’s landscape may glisten under a soft winter sun, inviting residents and visitors alike to relish the beauty of the season while looking forward to the brighter days that lie ahead.
In Walla Walla, the likelihood of sunny weather sees a notable decline as the year draws to a close. Starting with a relatively bright 23% chance in January, the percentage gradually climbs to a peak of 83% in July. However, by December, residents can expect only a 14% chance of sunshine, marking it as one of the gloomiest months of the year. This downward trend from autumn into winter highlights a significant seasonal shift, emphasizing the cozy yet overcast nature of December in this charming corner of the United States. With this low probability of sunny days, locals might want to plan for more indoor activities, embracing the season with warmth and comfort.
As December arrives in Walla Walla, the daylight duration begins to wane, with the sun gracing the skies for a mere eight hours each day. This decline marks the culmination of a gradual trend that begins in June, where daylight peaks at fifteen hours, then steadily diminishes as the year draws to a close. Following the vibrant stretch of spring and summer, where days lengthen to nearly their fullest, the transition into winter gives way to shorter, cozier days. Notably, December's daylight hours are the briefest of the year, contrasting sharply with the fourteen hours experienced in May. As Walla Walla shifts into the winter months, residents find themselves embracing the long nights, often filled with festive cheer and warm gatherings around the hearth.
In December, Walla Walla enjoys a gentle breeze, with an average wind speed of 2.9 m/s (7 mph), consistent with the wind patterns seen throughout the late fall and early winter months. Notably, while January typically starts the year with slightly stronger winds at 3.0 m/s, the trend shows a gradual decline into the summer months, reaching a seasonal low of 2.4 m/s in September. Interestingly, December's wind speeds are comparable to those of previous months, demonstrating a stable wintertime atmosphere. As the year winds down, the city embraces a serene yet refreshing air that complements the crispness of the season.
The weather in Walla Walla changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of December's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Walla Walla and find detailed weather information for every month.
In December, temperatures in Walla Walla range from a chilly minimum of -14°C (6°F) to a mild maximum of 18°C (65°F), with an average temperature of 1°C (34°F). The month experiences about 93 mm (3.7 in) of precipitation over 15 days, contributing to a relatively high humidity of 87%. In comparison, January sees even colder temperatures, with lows dropping to -19°C (-1°F) and a maximum of only 12°C (54°F), while maintaining the same average of 1°C (34°F). Precipitation decreases slightly to 77 mm (3.0 in) over 13 days, resulting in a similar humidity level of 86%. For a more detailed overview of January weather specifics, you can check Walla Walla weather in January.
December and February both experience chilly temperatures, with February often feeling even cooler with a minimum of -17°C (2°F) compared to December's minimum of -14°C (6°F). Despite similar average temperatures of around 1°C (34°F), February slightly edges out with a maximum of 16°C (61°F) compared to December's 18°C (65°F). Precipitation levels also increase from December to February, with February seeing 125 mm (4.9 in) of rain over 18 days, compared to December's 93 mm (3.7 in) over 15 days. Humidity remains relatively high in both months, with February at 86% and December slightly higher at 87%. For a more detailed look at February weather, visit Walla Walla weather in February.
In December, temperatures can drop to a chilly -14°C (6°F), with an average of 1°C (34°F) and a maximum of 18°C (65°F). The month sees around 93 mm (3.7 in) of precipitation over approximately 15 days, accompanied by high humidity at 87%. In contrast, March offers slightly milder conditions, with minimum temperatures around -12°C (11°F) and an average temperature of 5°C (41°F), while still reaching a maximum of 18°C (65°F). Precipitation decreases to approximately 75 mm (3.0 in) over about 13 days, and humidity levels remain relatively low at 85%. For more details, check out Walla Walla weather in March.
December weather is characterized by much colder temperatures, with a minimum of -14°C (6°F) and an average of just 1°C (34°F), compared to April's milder conditions where temperatures range from a minimum of -7°C (20°F) to an average of 9°C (48°F). While December experiences higher humidity, at 87%, and more precipitation across approximately 15 days totaling 93 mm (3.7 in), April sees slightly lower humidity at 83% and less rainfall, with 62 mm (2.4 in) falling over 11 days. The stark contrast in temperatures and precipitation highlights the shift from the bitter cold of winter to the budding warmth of spring. For more details, check out Walla Walla weather in April.
December and May present quite contrasting weather conditions. In December, temperatures can plunge to a minimum of -14°C (6°F), with an average of 1°C (34°F) and occasional highs reaching 18°C (65°F). The month is characterized by higher precipitation levels of 93 mm (3.7 in) over 15 days, paired with a humidity level of 87%, creating a chilly and damp atmosphere. In stark contrast, May experiences milder temperatures, starting from a minimum of -1°C (30°F) and averaging around 14°C (57°F), with maximum temperatures soaring up to 32°C (90°F). With only 48 mm (1.9 in) of precipitation over just 9 days and a lower humidity level of 77%, May offers a much more pleasant and dry climate. For more details, check out Walla Walla weather in May.
December and June present stark contrasts in weather. In December, temperatures can plummet to a chilling minimum of -14°C (6°F) with an average temperature around 1°C (34°F), while the maximum rarely exceeds 18°C (65°F). The month experiences significant precipitation of 93 mm (3.7 in) over about 15 days, accompanied by high humidity levels at 87%. In contrast, June offers a much milder experience, with temperatures ranging from a minimum of 4°C (39°F) to a balmy maximum of 43°C (110°F), and a comfortable average of 18°C (65°F). Precipitation is notably lower at 27 mm (1.1 in) across just 6 days, with humidity easing to 81%. For detailed insights, check out Walla Walla weather in June.
December and July present stark contrasts in weather. December experiences much colder temperatures, with a minimum of -14°C (6°F) and an average of 1°C (34°F), while July boasts a much warmer average of 23°C (74°F) and can reach highs of up to 39°C (103°F). Precipitation is more frequent in December, with 93 mm (3.7 in) over 15 days, in contrast to the almost arid conditions of July, which records only 2 mm (0.1 in) over no rainy days. Additionally, December has higher humidity levels at 87%, compared to July's 76%, further emphasizing the seasonal differences. For more detailed insights on July weather, check out Walla Walla weather in July.
December and August present striking contrasts in weather conditions. In December, temperatures can drop as low as -14°C (6°F) with an average around 1°C (34°F), while the maximum can reach 18°C (65°F). The month is marked by significant precipitation, averaging 93 mm (3.7 in) over approximately 15 days, and high humidity at 87%. In contrast, August showcases much warmer temperatures, with lows of 6°C (42°F) and an average of 22°C (72°F), peaking at a sweltering 39°C (102°F). Precipitation is minimal in August, averaging just 8 mm (0.3 in) over a single day, coupled with lower humidity at 60%. For more detailed information about August conditions, you can check Walla Walla weather in August.
December and September present contrasting weather characteristics. In December, temperatures can drop to a minimum of -14°C (6°F) with an average of around 1°C (34°F) and a maximum of 18°C (65°F), creating a chilly atmosphere with frequent precipitation of 93 mm (3.7 in) over 15 days and high humidity at 87%. In stark contrast, September boasts milder conditions, with temperatures ranging from a minimum of 1°C (35°F) to an average of 17°C (62°F) and soaring highs of up to 36°C (97°F). Precipitation during this month is significantly lower at 25 mm (1.0 in) over just 4 days, accompanied by a more moderate humidity level of 58%. For more details on September weather in Walla Walla, refer to Walla Walla weather in September.
When comparing the weather in December to that of October, several key differences emerge. December experiences a colder temperature range, with minimums dropping to -14°C (6°F) and an average of around 1°C (34°F), while October has milder temperatures, with lows of -11°C (13°F) and an average of 9°C (49°F). Additionally, December sees more precipitation, totaling 93 mm (3.7 in) over about 15 days, compared to October's 62 mm (2.4 in) over 10 days. Humidity is also higher in December at 87%, compared to 75% in October. These factors contribute to a much chillier and wetter December, making October a generally more temperate month. For a detailed look at October conditions, you can explore Walla Walla weather in October.
In comparing the weather of December to that of November, December tends to be colder overall, with average temperatures dropping from 5°C (41°F) in November to 1°C (34°F) in December. December also experiences a wider temperature range, with minimum temperatures reaching as low as -14°C (6°F), compared to November's minimum of -9°C (17°F). Precipitation is slightly higher in December, totaling 93 mm (3.7 in) over 15 days, while November sees 84 mm (3.3 in) over 13 days. Humidity remains quite similar, with December at 87% and November at 85%. For more detailed information about November's weather, you can visit Walla Walla weather in November.
As December settles in, Walla Walla transforms into a winter wonderland, with its weather showcasing a notable shift from the milder months. The chilly air brings a stark contrast, with temperatures often dipping significantly, and the landscape becomes gripped by frost. December also sees increased precipitation, with nearly half the month experiencing rain or snow, leading to a more humid atmosphere. This month’s distinct chill and moisture contribute to a unique charm, making it ideal for cozy gatherings and reflecting on the year. For more insights on what to expect throughout the year, check out Walla Walla Climate.