Last updated: February 24, 2025
In December, Castle Rock experiences a broad range of temperatures, with an exhilarating maximum reaching 21°C (70°F), contrasted by a chilling minimum of -21°C (-5°F). The average temperature hovers around a brisk -1°C (30°F), adding to the month's wintry charm. Residents and visitors may encounter light precipitation, totaling 9 mm (0.4 in) over just 3 days, while humidity levels remain relatively high at 80%. This combination of characteristics creates a unique and captivating atmosphere perfect for embracing the seasonal change.
In December, temperatures in Castle Rock, United States, begin to reflect the deepening winter chill. With a minimum of -21°C (-5°F) and an average hovering around -1°C (30°F), the month showcases a trend of low temperatures yet introduces a slight warming compared to the colder months that precede it. The maximum temperature can reach up to 21°C (70°F), highlighting the transitional nature of this month. As the year draws to a close, Castle Rock experiences a typical winter tapestry, blending brisk cold with the occasional milder spell, making it a fascinating time for both residents and visitors alike.
As the final month of the year, December in Castle Rock brings a noticeable drop in precipitation, with just 9 mm (0.4 in) over 3 days. This decline is part of a broader trend observed throughout the colder months, where amounts decrease significantly from the spring and summer highs. For instance, while May peaks at 87 mm (3.4 in) across 14 days, the year ends with a stark contrast. The reduction in precipitation days also highlights the shift to drier conditions as winter sets in. Overall, December wraps up the year's weather narrative, emphasizing a cycle of increasing dryness following the wetter months.
As December rolls in, Castle Rock experiences a notable rise in humidity, reaching 80%, which ties with the peak levels seen in August. This increase indicates a trend towards a more humid winter compared to the drier months of spring and early fall. Throughout the year, humidity fluctuates, with a noticeable drop in March and April, when levels dip to 66% and 62% respectively. However, this winter spike signifies that residents may want to brace for a wet season, adding a touch of moisture to the crisp winter air. Overall, the annual cycle showcases a consistent pattern of higher humidity in the summer months, gradually transitioning into a more humid December, setting the stage for a cozy end to the year.
As the year winds down in Castle Rock, United States, December welcomes a moderate UV Index of 4, similar to January's readings. This indicates a shift from the extreme UV levels experienced during the summer months, where the index peaked at 12 in May through July. As we transition to winter, residents and visitors can enjoy outdoor activities with a more relaxed approach to sun protection, with a burn time of 30 minutes before needing to seek shade. However, it's essential to remember that even in December, UV rays can still pose a risk during peak hours. For detailed insights on UV levels throughout the year, check the Castle Rock UV Index.
UV Risk Categories
As December graces Castle Rock, the sunshine echoes the city's gradual transition into winter, with 244 hours of glorious sunlight to enjoy. This month maintains a steady glow, albeit a slight dip from the vibrant 332 hours basked in during May, and the sunniest peak of 372 hours in July. Notably, December's sunshine reflects a consistent trend of diminishing daylight as the year closes, following the pattern of increased hours from January's mere 189 hours. The cold and clear December sky invites residents to embrace the festive brilliance, highlighting the refreshing interplay between the year’s shifting seasons, where even the less bright months hold their unique charm.
In December, Castle Rock enjoys a notably high likelihood of sunny weather, with a 75% chance of sunshine, making it one of the sunniest months of the year. This trend marks an upswing compared to the preceding months, where percentages tend to hover in the lower to mid-60s. Notably, December outshines not only the winter months but also outperforms several key months from spring and summer, highlighting a unique seasonal transition. As the calendar year wraps up, residents and visitors alike can anticipate a December filled with bright, sunny days, perfect for holiday festivities and outdoor activities under the clear blue skies.
As December sets in Castle Rock, daylight hours dwindle to 9 hours, mirroring the shorter days of January. This seasonal trend reflects a gradual decline from the summer's peak daylight of 14 hours experienced in June, July, and August. Following the vibrant spring months that gift us with longer days, daylight begins its retreat in September and continues to do so through the fall, culminating in the winter months where sunlight is at its most precious. The cyclical nature of daylight in Castle Rock not only marks the passing of the year but also encourages a cozy embrace of the winter's early evenings.
In December, Castle Rock experiences a notable uptick in wind speed, with an average of 2.8 m/s (6 mph), marking it as one of the breezier months of the year. This shift reflects a gentle increase from the consistently low winds of the earlier months, where speeds hovered around 2.3 m/s (5 mph). While March and April also see brief rises to 2.9 m/s (6 mph) and 2.7 m/s (6 mph) respectively, December stands out as a time when the winter chill joins forces with a refreshing breeze, hinting at the seasonal transition. The overall trend suggests that as the year winds down, Castle Rock comes alive with a captivating mix of chilly air and invigorating gusts, perfect for those who embrace the outdoors in the midst of winter’s embrace.
The weather in Castle Rock 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 Castle Rock and find detailed weather information for every month.
In December, temperatures vary more dramatically, ranging from a chilly minimum of -21°C (-5°F) to a mild maximum of 21°C (70°F), with an average temperature of -1°C (30°F). The month sees limited precipitation at 9 mm (0.4 in) over just three days, while humidity levels are relatively high at 80%. In contrast, January consistently brings colder weather, with a lower minimum temperature of -26°C (-15°F) and an average of -3°C (27°F), peaking at 17°C (62°F). Precipitation increases in January to 17 mm (0.7 in), also over three days, though the humidity decreases to 74%. Thus, January weather appears colder and slightly wetter than December. For more detailed information, check out Castle Rock weather in January.
December and February present contrasting weather patterns. December experiences a milder temperature range, with minimums around -21°C (-5°F) and an average of -1°C (30°F), while the maximum can reach up to 21°C (70°F). In contrast, February sees even colder temperatures, where the minimum can drop to -30°C (-22°F) and averages around -3°C (26°F), though it can still peak at 22°C (72°F). Precipitation is notably higher in February, with 22 mm (0.9 in) over 7 days, compared to December's 9 mm (0.4 in) across 3 days. Humidity levels are slightly lower in February at 75%, compared to the higher 80% seen in December. For more detailed insights on the weather, please visit Castle Rock weather in February.
In December, temperatures typically range from a chilly -21°C (-5°F) to a pleasant high of 21°C (70°F), with an average temperature hovering around -1°C (30°F). This month sees relatively low precipitation of 9 mm (0.4 in) over just three days and maintains a high humidity level of 80%. In contrast, March experiences slightly colder nights with temperatures dipping to -24°C (-10°F) but enjoys warmer days that can reach up to 24°C (76°F), with an average of 2°C (36°F). Notably, March has higher precipitation at 59 mm (2.3 in) occurring over seven days, leading to a decrease in humidity to 66%. For more details on specific conditions, check out Castle Rock weather in March.
December and April showcase striking differences in weather patterns. In December, temperatures can plummet to a minimum of -21°C (-5°F), with an average around -1°C (30°F) and occasional peaks reaching up to 21°C (70°F). The month is characterized by low precipitation, averaging only 9 mm (0.4 in) over just three days, accompanied by a high humidity level of 80%. In contrast, April experiences milder temperatures, with minimums around -18°C (0°F) and an average of 6°C (43°F), reaching a maximum of 27°C (82°F). This month sees significantly higher precipitation at 42 mm (1.7 in), spread over nine days, and a lower humidity of 62%. For a closer look at the weather specifics during April, you can refer to Castle Rock weather in April.
In December, the weather is typically much colder, with average temperatures hovering around -1°C (30°F) and lows plummeting to -21°C (-5°F). The month experiences minimal precipitation, with just 9 mm (0.4 in) over three days, accompanied by a high humidity level of 80%. In contrast, May brings a noticeable warming trend, with average temperatures rising to 11°C (53°F) and maximums reaching 31°C (88°F). However, May is significantly wetter, receiving 87 mm (3.4 in) of rain over 14 days, coupled with a slightly lower humidity of 74%. For detailed weather insights, you can check Castle Rock weather in May.
December and June present starkly contrasting weather conditions. In December, temperatures can plummet to a minimum of -21°C (-5°F) and hover around an average of -1°C (30°F), with an occasional high of 21°C (70°F). The month experiences low precipitation, totaling just 9 mm (0.4 in) over about 3 days, along with fairly high humidity at 80%. In contrast, June brings a milder climate, showcasing a minimum temperature of 2°C (35°F) and an average that rises to 18°C (65°F), peaking at a high of 35°C (96°F). However, June also sees increased precipitation, with 45 mm (1.8 in) falling over approximately 8 days and slightly lower humidity at 76%. For more specifics on June conditions, you can check Castle Rock weather in June.
December and July present starkly contrasting weather conditions. In December, temperatures can drop as low as -21°C (-5°F), with an average of -1°C (30°F) and a maximum reaching 21°C (70°F). The month experiences low precipitation, with only 9 mm (0.4 in) over three days and relatively high humidity at 80%. In contrast, July boasts much warmer temperatures, with a minimum of 8°C (47°F), an average of 21°C (70°F), and a peak temperature of 35°C (95°F). This month sees significantly more rainfall, with 59 mm (2.3 in) spread over 11 days, while humidity remains at a comfortable 75%. For those interested in specific details regarding July weather, you can find more information here: Castle Rock weather in July.
When comparing December and August weather, the differences are quite striking. December experiences extremely low temperatures, with a minimum of -21°C (-5°F) and a maximum of 21°C (70°F), while the average temperature hovers around -1°C (30°F). Precipitation is minimal, totaling only 9 mm (0.4 in) over 3 days, coupled with high humidity at 80%. In contrast, August enjoys milder temperatures, ranging from a minimum of 7°C (45°F) to a maximum of 33°C (92°F), with an average of 20°C (68°F). However, it also sees more precipitation, with 42 mm (1.6 in) spread over 9 days, while maintaining the same humidity level of 80%. For a more detailed look at the climate during this summer month, visit Castle Rock weather in August.
December and September present stark contrasts in weather patterns. December experiences a wider temperature range, with a minimum of -21°C (-5°F) and a maximum of 21°C (70°F), while September is much milder, with temperatures ranging from a minimum of -4°C (26°F) to a maximum of 33°C (92°F). Additionally, September tends to be wetter, with 34 mm (1.3 in) of precipitation over 6 days compared to December's 9 mm (0.4 in) of precipitation over just 3 days. Humidity levels are slightly higher in December at 80%, compared to September's 79%. For more specific insights into September's weather, you can check out Castle Rock weather in September.
In comparing the weather of December and October, we observe notable differences in temperature and precipitation. December experiences a milder average temperature of -1°C (30°F) with fewer extreme lows, while October sees colder minimum temperatures at -23°C (-9°F) but warmer maximums reaching 28°C (83°F). Precipitation is significantly lower in December, with only 9 mm (0.4 in) over three days, compared to October's 33 mm (1.3 in) across six days. Additionally, humidity levels are slightly higher in December at 80%, compared to October's 77%. For those interested in more detailed weather patterns, you can check Castle Rock weather in October.
Comparing the weather between November and December reveals some notable differences. In December, the average temperature is slightly lower at -1°C (30°F), with a maximum temperature of 21°C (70°F). In contrast, November experiences a slightly warmer average temperature of 2°C (37°F) and peaks at 24°C (75°F). Precipitation is also less in December, with only 9 mm (0.4 in) across 3 days, compared to November's 20 mm (0.8 in) over 4 days. Additionally, December's humidity is higher at 80%, while November sits at 74%. For more detailed insights, check out Castle Rock weather in November.
As December settles over Castle Rock, residents experience a notable shift in weather compared to other months. With temperatures swinging from a chilly minimum of -21°C to a pleasant maximum of 21°C, this month serves as a vivid reminder of winter's embrace. The average temperature hovers around a brisk -1°C, while humidity levels rise to 80%, contributing to the crispness in the air. December is also relatively dry, boasting only 9 mm of precipitation over just three days, offering a unique blend of wintry charm without overwhelming snowfall. This month stands out in the year as a time for cozy gatherings and festive spirit. For a more detailed exploration of Castle Rock's atmospheric conditions, check out Castle Rock Climate.