Last updated: February 24, 2025
In December, Sisters, United States experiences a unique blend of winter chill and moisture, with average temperatures hovering around 0°C (33°F). The month sees maximum temperatures reaching up to 18°C (65°F), but the thermometer can plunge to a minimum of -19°C (-2°F), showcasing the area's temperature variability. Residents can expect 93 mm (3.7 in) of precipitation over about 14 days, contributing to an atmosphere of 88% humidity that accentuates the cold. This combination of factors creates a distinctive winter wonderland, ideal for both outdoor enthusiasts and those seeking the cozy embrace of the season.
In December, the temperatures in Sisters, Oregon, usher in the heart of winter with a distinct chill, showcasing a minimum of -19°C (-2°F), while the average hovers around a crisp 0°C (33°F). As the month progresses towards the New Year, the maximum temperature climbs to a mild 18°C (65°F), hinting at the variability that characterizes the region’s winter climate. Notably, December marks a transition from the biting cold of November, where lows dipped to -18°C (0°F), suggesting a gradual warming trend as winter unfolds. This month balances frosty nights and cool days, reflecting the blend of winter's intensity with occasional respite, ideal for those who revel in the beauty of a snow-dusted landscape while bundled up against the chill.
In December, Sisters, United States, experiences a significant uptick in precipitation, with 93 mm (3.7 in) of rain falling over 14 days. This marks a return to wetter conditions after the drier summer months of June and July, which see only a few millimeters of rainfall. Precipitation levels in December are on par with January, both months grappling with similar amounts of moisture. As winter sets in, the frequency of rainy days increases, hinting at a shift from the drier autumn months, where November received 74 mm (2.9 in) across 11 days. This seasonal transition underscores a trend of heightened precipitation as the region heads into winter, suggesting a cozy end to the year for residents and nature alike.
In Sisters, United States, December ushers in a notable increase in humidity, reaching 88%—a figure that aligns closely with the high humidity often experienced in November. This late fall spike contrasts sharply with the summer months, where humidity levels dip significantly to a low of 62% in August. As the year progresses towards winter, a gradual rise is evident, especially in the transition from the warmer months of July, August, and September, where humidity plummets, to the wetter conditions typical of late autumn and early winter. Overall, December’s humidity reflects a cyclic trend, marked by heightened moisture in winter months, inviting a crisp, cooler atmosphere characteristic of the season.
In December, Sisters, United States, experiences a shift in UV Index, dropping to 2, which falls in the low exposure category. This means residents and visitors can enjoy outdoor activities with a longer burn time of 45 minutes before needing to worry about sun damage. The month wraps up a year characterized by significant fluctuations, with peak indices in late spring and summer reaching an extreme 11 in May, where the burn time shortens considerably to just 10 minutes. As the seasons turn, individuals can look forward to the gentler rays of winter, allowing for safer outdoor enjoyment while still keeping UV exposure in mind. For more detailed insights, check out the Sisters UV Index.
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In Sisters, United States, December brings a gentle reduction in sunshine hours, with the month averaging around 144 hours of bright daylight. As the year winds down, this figure reflects a noticeable dip after the sunniest peak in July, which enjoys an impressive 409 hours. The transition into winter is marked by a gradual decline from November’s 168 hours, setting the stage for the upcoming months. Despite the shorter days, December still offers a taste of sunshine, inviting residents and visitors to embrace the crisp winter landscape while reflecting on the vibrant warmth that characterized the earlier months like May and June, each boasting over 330 hours of golden rays. The rhythm of light in Sisters highlights a unique charm of seasonal change, making each month distinctly captivating.
As December rolls around in Sisters, United States, the likelihood of enjoying sunny weather dwindles, with only a 17% chance of sunshine. This stark contrast to the sunnier summer months, where July boasts an impressive 83% chance of sun, highlights the region's seasonal variability. The trend reveals a gradual decline in sunny days from the warmer months, with November already dipping to 25%, and December taking a further plunge into cloudier conditions. This pattern underscores the colder season, where the landscape transitions to a more overcast appearance, inviting moments of cozy indoor relaxation rather than outdoor sunshine-filled activities.
As the year comes to a close, December in Sisters, United States, ushers in the shortest days, with just 8 hours of daylight. This marks a clear contrast to the long, sun-drenched days of June and July, each boasting 15 hours of bright sunshine. The shift from the vibrant 14 hours in May to the dwindling light of mid-winter highlights a distinct seasonal trend. As autumn closes out, the gradual decline in daylight from 12 hours in September to just 9 hours in November culminates in December's twilight, inviting the community to embrace a cozy, reflective season before the gradual return of brighter days begins anew in January.
In December, the winds in Sisters, United States, pick up slightly, reaching an average speed of 2.7 m/s (6 mph), a bit stronger compared to the tail end of the year. This gentle increase contrasts with the trend observed over the preceding months, where wind speeds hovered around 2.2 to 2.5 m/s (5 mph) from July to November. As winter settles in, these breezier conditions in December might hint at the seasonal shifts, inviting residents to enjoy the crisp air while wrapped in their warmest layers. Overall, the modest wind variability throughout the year reflects the region's tranquil yet dynamic climate, making each gust a refreshing reminder of nature's rhythm.
The weather in Sisters 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 Sisters and find detailed weather information for every month.
December and January exhibit striking similarities in terms of average precipitation and humidity, yet they differ significantly in temperature. In December, temperatures range from a minimum of -19°C (−2°F) to a maximum of 18°C (65°F), making it a month that can experience quite a range. In contrast, January is colder, with minimum temperatures dropping to -24°C (−11°F) and maximums only reaching 14°C (57°F). Both months see similar precipitation, around 93 mm (3.7 in), but the number of rainy days decreases slightly in January, with precipitation occurring on 13 days compared to 14 days in December. For a more detailed look at January weather, you can explore Sisters weather in January.
December and February share similar average temperatures, both hovering around 0°C (33°F), but February tends to be slightly colder with a minimum temperature of -22°C (-7°F) compared to December's minimum of -19°C (-2°F). December experiences 93 mm (3.7 in) of precipitation over approximately 14 days, while February sees a bit more with 109 mm (4.3 in) spread over 15 days, indicating a generally wetter trend in the latter month. Humidity levels are also similar, with December at 88% and February slightly lower at 87%. For a more detailed insight into February weather, you can check Sisters weather in February.
December and March present distinct weather patterns, reflecting the transition from winter to early spring. In December, temperatures can plunge to a minimum of -19°C (-2°F), with an average around 0°C (33°F) and a maximum reaching 18°C (65°F). The month experiences considerable precipitation, totaling 93 mm (3.7 in) over 14 days, alongside high humidity at 88%. In contrast, March features milder temperatures, with a minimum of -15°C (5°F) and an average of 3°C (38°F), slightly warmer than December, peaking at 19°C (67°F). March also sees reduced precipitation at 66 mm (2.6 in) across 13 days, and a humidity level of 86%. For more insights on conditions during this time, you can check Sisters weather in March.
In December, temperatures can drop significantly, with lows reaching -19°C (-2°F) and an average of around 0°C (33°F), making it one of the coldest months of the year. The month experiences about 93 mm (3.7 in) of precipitation over 14 days, coupled with a high humidity of 88%. In contrast, April brings a much milder climate, where temperatures range from a minimum of -8°C (17°F) to an average of 7°C (45°F), with maximums occasionally peaking at 28°C (83°F). April sees reduced precipitation at 67 mm (2.6 in) across 11 days and slightly lower humidity at 85%. For a closer look at the weather patterns during this time, visit Sisters weather in April.
In December, the weather is significantly colder with temperatures ranging from a minimum of -19°C (-2°F) to a maximum of 18°C (65°F) and an average temperature of around 0°C (33°F). The month experiences substantial precipitation, totaling 93 mm (3.7 in) over approximately 14 days, contributing to a high humidity level of 88%. In contrast, May offers a much milder climate, with temperatures varying from a minimum of -5°C (23°F) to a comfortable maximum of 31°C (88°F) and an average of 12°C (53°F). Precipitation in May drops to 37 mm (1.5 in) over about 8 days, and humidity levels slightly decrease to 80%. This transition from the harsh winter of December to the warmer spring of May underscores a dramatic shift in weather patterns. For more details on the weather in May, you can refer to Sisters weather in May.
December and June present stark contrasts in weather. In December, temperatures can plunge to a minimum of -19°C (-2°F) and have an average of 0°C (33°F), with a maximum reaching 18°C (65°F). This month experiences significant precipitation, totaling 93 mm (3.7 in) over about 14 days, coupled with high humidity at 88%. In stark contrast, June showcases a much warmer climate, with temperatures ranging from a minimum of 0°C (32°F) to an impressive maximum of 42°C (108°F) and an average of 16°C (61°F). Precipitation is minimal in June, amounting to only 22 mm (0.9 in) across 6 days, and humidity is slightly lower at 82%. For more details about the weather in June, you can check out Sisters weather in June.
December and July present strikingly different weather conditions. In December, temperatures range from a chilly -19°C (2°F) to a mild 18°C (65°F), with an average around 0°C (33°F). The month also sees significant precipitation, with 93 mm (3.7 in) falling over approximately 14 days, contributing to an overall high humidity of 88%. In contrast, July boasts a much warmer temperature range, with minimums of 0°C (33°F) and maximums reaching up to 37°C (99°F), resulting in a comfortable average of 20°C (69°F). July remains relatively dry, with just 6 mm (0.3 in) of rainfall over a single day, and a lower humidity level of 78%. For more detailed information on July conditions, you can check Sisters weather in July.
December and August present stark contrasts in weather patterns. In December, temperatures can plummet to a minimum of -19°C (-2°F) and hover around an average of 0°C (33°F), with a maximum reaching 18°C (65°F). Additionally, the month experiences significant precipitation, averaging 93 mm (3.7 in) over about 14 days, accompanied by high humidity at 88%. In contrast, August boasts a much milder climate, with temperatures ranging from a minimum of 0°C (33°F) to a sizzling maximum of 37°C (100°F) and an average of 20°C (68°F). Precipitation is minimal during this month, totaling only 8 mm (0.3 in) across just 2 days, and the humidity is notably lower at 62%. For more details about the weather in August, you can visit Sisters weather in August.
December weather presents a stark contrast to September's climate. In December, temperatures can plummet to a minimum of -19°C (-2°F), with an average temperature around 0°C (33°F) and occasional highs reaching 18°C (65°F). This month also sees significant precipitation, totaling 93 mm (3.7 in) over about 14 days, along with high humidity levels averaging 88%.
In comparison, September enjoys a mild climate with min temperatures around -3°C (26°F) and an average of 15°C (59°F), peaking at a sweltering 37°C (99°F). Precipitation is much lighter at just 36 mm (1.4 in) over 5 days and humidity is lower at 59%. This makes September feel far more temperate and pleasant than the chill of December. For more details on September weather, visit Sisters weather in September.
In comparing the weather between December and October, December tends to be significantly colder, with temperatures ranging from a minimum of -19°C (-2°F) to a maximum of 18°C (65°F), and an average temperature of around 0°C (33°F). In contrast, October offers milder conditions, featuring a minimum of -9°C (16°F) and a maximum of 30°C (87°F), with an average temperature of 8°C (47°F). Moreover, December experiences more precipitation, totaling 93 mm (3.7 inches) over 14 days, while October has only 43 mm (1.7 inches) over 7 days. The humidity in December is also higher at 88%, compared to October's 78%. For more details on October weather, you can visit Sisters weather in October.
In comparing the weather between November and December, we see a notable trend in temperature and precipitation. December experiences slightly colder temperatures, with a minimum of -19°C (-2°F), compared to November's minimum of -18°C (0°F). The average temperature in December drops to 0°C (33°F), whereas November has a milder average of 3°C (38°F).
Although both months have high humidity levels at 88%, December sees a slightly higher total precipitation of 93 mm (3.7 in) over 14 days, compared to November's 74 mm (2.9 in) over 11 days. This increase in precipitation may contribute to the chillier atmosphere experienced in December. For a more detailed look at the weather patterns, you can explore Sisters weather in November.
As December descends upon Sisters, the weather transforms dramatically, marking a departure from the milder months of autumn. With temperatures dipping significantly, the crisp air becomes a defining feature of the landscape, making way for a frosty ambiance. In this month, increased precipitation and higher humidity contribute to a more wintry feel, contrasting sharply with the dry, warm conditions experienced earlier in the year. This combination not only brings layered snowfall but also invites a cozy atmosphere perfect for the holiday season. To explore more about how December's climate sets itself apart, visit Sisters Climate.