Last updated: February 24, 2025
December in Mount Vernon, United States, presents a blend of chilly temperatures and noteworthy precipitation. With maximum temperatures reaching 21°C (69°F) and minimums plunging to -9°C (16°F), the average temperature settles around a brisk 6°C (44°F). The month is characterized by 97 mm (3.8 in) of rainfall across 10 days, contributing to the high humidity level of 84%. Residents and visitors can expect a wintry mix that makes for a picturesque yet cool December ambiance.
As December rolls into Mount Vernon, temperatures begin to dip, ushering in the winter season with a minimum of -9°C (16°F). The average temperature hovers around 6°C (44°F), providing a chill that contrasts sharply with the preceding months. This middle ground between the mild fall and the harsher January cold features a pleasant maximum of 21°C (69°F), suggesting that winter's grip is still finding its feet. Notably, after November's frosty plunge to -4°C (24°F), December presents a slight warming trend, offering a blend of cold and mild days. With each day that passes, residents can expect to see more evidence of winter's arrival, making this month a transition into the snowy months ahead.
In December, Mount Vernon experiences a notable shift in precipitation, receiving an average of 97 mm (3.8 in) over approximately 10 days. This marks a slight decrease from the wetter months of July and August, where rainfall peaked at 139 mm (5.5 in) and 149 mm (5.8 in), respectively. Despite this reduction, December maintains a consistent level of precipitation similar to that of the preceding months, highlighting late autumn’s lingering moisture. The transition into winter often brings a more stable distribution of rainfall, setting the stage for the drier months ahead. As temperatures drop, the blend of rain and potential snow adds a unique character to the region’s winter landscape, making December a dynamic month in Mount Vernon's climatic calendar.
December in Mount Vernon sees a relative humidity of 84%, marking a slight decrease from the previous month's high of 85%. Throughout the year, humidity levels exhibit a noticeable trend; they tend to be highest in the winter months, peaking in November, before slightly tapering in December. As the colder months progress, the humidity remains relatively high compared to the summer months, where July and August experience the driest conditions at 74% and 72%, respectively. This seasonal fluctuation highlights Mount Vernon's characteristic damp winters, a contrast to its warmer, more arid summer climate. The consistent humidity levels in December contribute to the region's cool and sometimes brisk atmosphere, embodying the essence of winter in this charming locale.
In Mount Vernon, United States, the UV Index experiences notable fluctuations throughout the year. January starts off with a moderate index of 3, allowing for safer outdoor activities without immediate risk of sunburn, which continues into November. As spring approaches, the UV Index begins to rise, peaking at 10 in May through August when the risk of harm from unprotected sun exposure is at its highest, demanding extra caution in the sun. Moving into December, the UV Index dips back down to a moderate 3, similar to the start of the year, providing a break from the intense rays of the mid-year months. This cyclical pattern highlights the importance of remaining vigilant about sun safety, regardless of the season. For more detailed information, visit Mount Vernon UV Index.
UV Risk Categories
In Mount Vernon, United States, December marks a distinct transition in daylight hours as the year draws to a close, bringing a total of 193 hours of sunshine. This reflects a noticeable decrease from the sun-drenched summer months, which boast an impressive peak of 366 hours in July. The gradual decline in sunshine is evident as we progress through the latter part of the year, with November clocking in at 230 hours. However, December still offers a respectable amount of daylight, especially when juxtaposed with January's 161 hours. As winter settles in, residents can appreciate the crisp air and the subtle beauty that December sunlight brings, reminding us that even in the darkest months, pockets of brightness continue to shine through.
In Mount Vernon, the likelihood of sunny weather sees a notable decline in December, dropping to 42%. This trend follows a generally fluctuating pattern throughout the year, with the highest chances of sunshine typically occurring in the spring and early fall, particularly in September (58%) and March (51%). Interestingly, November also boasts a robust 57% chance of sunny days, suggesting a brief reprieve before the winter gloom sets in. As we transition into December, the sun's presence becomes less predictable, setting a tone of introspection as residents prepare for the colder, cloudier months ahead.
In Mount Vernon, December brings a return to the shorter daylight hours, with just 9 hours of sunlight to brighten the winter days. This is consistent with the trend observed throughout the year, where daylight begins at 9 hours in January, gradually increasing to a peak of 14 hours during the summer months of June, July, and August. As autumn approaches, daylight gradually dwindles, tapering down to 10 hours in November before hitting its lowest point in December. This cyclical pattern illustrates the seasonal rhythm of sunlight in Mount Vernon, offering a gentle reminder of the vibrant longer days ahead as winter transitions into spring.
As December settles in Mount Vernon, the winds typically ripple through at an average speed of 3.5 m/s (8 mph), aligning closely with the softer gusts observed during the summer months. This slight breeze, while less vigorous than the early winter months, reflects a downward trend from the peak wind speeds seen in November at 3.9 m/s (9 mph). Interestingly, December also mirrors the gentler winds of May and October, creating a serene atmosphere that contrasts the lively gales of earlier months. Overall, as the year winds down, the transition to a more tranquil December encapsulates the region's seasonal ebb and flow, inviting a peaceful embrace of the winter chill.
The weather in Mount Vernon 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 Mount Vernon and find detailed weather information for every month.
In December, temperatures range from a minimum of -9°C (16°F) to a maximum of 21°C (69°F), with an average of 6°C (44°F). The month sees substantial precipitation, totaling 97 mm (3.8 in) over about 10 days, paired with consistent humidity levels around 84%. In contrast, January experiences colder conditions with a minimum of -16°C (3°F) and an average temperature of 4°C (39°F), while the maximum remains similar at 20°C (69°F). Precipitation decreases to 71 mm (2.8 in) spread over 9 days, maintaining the same high humidity. For more details on January weather, check Mount Vernon weather in January.
December and February weather display some similarities and differences. In December, temperatures range from a chilly minimum of -9°C (16°F) to a comfortable maximum of 21°C (69°F), with an average of 6°C (44°F). The month experiences around 10 days of precipitation, totaling 97 mm (3.8 in), and a humidity level of 84%.
In contrast, February sees slightly colder temperatures, with a minimum of -11°C (12°F) and a maximum of 23°C (74°F), maintaining a similar average of approximately 6°C (43°F). February has a marginal reduction in precipitation, measuring 94 mm (3.7 in) over 11 days, while humidity remains comparable at 83%.
For more detailed insights into the weather during this month, visit Mount Vernon weather in February.
December and March exhibit notable differences in weather patterns. December features a lower average temperature of 6°C (44°F), with nighttime lows dropping to -9°C (16°F) and daytime highs reaching up to 21°C (69°F). Additionally, it sees a slight increase in humidity at 84% and a total precipitation of 97 mm (3.8 in) over approximately 10 days. In contrast, March experiences a milder climate, with an average temperature of 9°C (48°F) and maximum temperatures soaring to 28°C (83°F), while nighttime lows are slightly higher at -6°C (22°F). Precipitation in March is marginally less, at 91 mm (3.6 in) also spread over 10 days, maintaining a lower humidity level of 83%. For more details on March weather, you can visit Mount Vernon weather in March.
In December, the weather is characterized by a broader range of temperatures, with lows dipping to -9°C (16°F) and occasional highs reaching 21°C (69°F). This month experiences an average temperature of about 6°C (44°F) and sees significant precipitation, totaling 97 mm (3.8 in) over approximately 10 days, coupled with high humidity levels at 84%. In contrast, April brings a more moderate climate, featuring temperatures that start at a minimum of 0°C (32°F), average around 14°C (58°F), and peak at 30°C (87°F). With 88 mm (3.5 in) of precipitation spread over 11 days and a slightly lower humidity of 81%, April showcases a transition into warmer and more pleasant weather. For more detailed information on April weather, visit Mount Vernon weather in April.
December and May present stark contrasts in weather conditions. In December, temperatures can drop to a chilly minimum of -9°C (16°F), with an average of 6°C (44°F) and a maximum reaching 21°C (69°F). The month sees significant precipitation, totaling 97 mm (3.8 in) over about 10 days and a high humidity level of 84%. In contrast, May brings much milder and warmer weather, with temperatures ranging from a minimum of 5°C (42°F) to an average of 19°C (67°F) and soaring up to 33°C (91°F). Precipitation is slightly higher at 104 mm (4.1 in) over 11 days, but humidity decreases to 78%. For further details on the specific weather patterns, visit Mount Vernon weather in May.
December and June present stark contrasts in weather conditions. In December, temperatures can plummet to a minimum of -9°C (16°F), while the average sits around 6°C (44°F), and the maximum reaches 21°C (69°F). The month is characterized by high humidity at 84% and approximately 97 mm (3.8 in) of precipitation over 10 days. In contrast, June boasts a much milder climate with minimum temperatures of 12°C (54°F) and an average high of 24°C (75°F), peaking at a warm 33°C (91°F). June receives slightly more precipitation at 106 mm (4.2 in) over 12 days but enjoys lower humidity at 79%. For more detailed information, check out Mount Vernon weather in June.
When comparing the weather in December and July, notable contrasts emerge. December experiences much cooler temperatures, with a minimum of -9°C (16°F) and an average of 6°C (44°F), while July boasts significantly warmer conditions, with a minimum of 15°C (60°F) and an average of 27°C (81°F). Precipitation levels are also higher in July, totaling 139 mm (5.5 in) over 13 days, compared to December's 97 mm (3.8 in) across 10 days. Additionally, December's humidity stands at a high of 84%, contributing to a chillier feel, whereas July's humidity is lower at 74%, favoring a warmer and more comfortable atmosphere. For more details, check out Mount Vernon weather in July.
December and August offer starkly contrasting weather experiences. In December, temperatures can plunge as low as -9°C (16°F) and average around 6°C (44°F), while August boasts much warmer conditions, with minimums around 17°C (63°F) and averages reaching 26°C (79°F). Precipitation is more frequent in August, with 149 mm (5.8 in) spread over about 15 days, compared to December's 97 mm (3.8 in) over 10 days. Additionally, December's high humidity at 84% creates a chillier atmosphere, whereas August presents a more comfortable humidity level at 72%. For a detailed look at August weather specifically, you can visit Mount Vernon weather in August.
In comparing the weather of December and September, a stark contrast emerges. December typically sees much colder temperatures, with a minimum of -9°C (16°F) and an average of 6°C (44°F), while September boasts a much milder minimum of 11°C (51°F) and an average high of 23°C (74°F). Although both months receive similar levels of precipitation, around 97 mm (3.8 in) for December and 100 mm (3.9 in) for September, the overall feel is different, as December experiences a higher humidity level at 84% compared to September's 75%. For a detailed look at September weather, check out Mount Vernon weather in September.
When comparing the weather in December and October, it's evident that October tends to be significantly warmer. In October, temperatures range from a minimum of 4°C (40°F) to a maximum of 32°C (91°F), with an average temperature of 18°C (64°F). In contrast, December sees much cooler temperatures, with a minimum of -9°C (16°F) and a maximum of 21°C (69°F), averaging only 6°C (44°F). Additionally, October experiences slightly more precipitation at 117 mm (4.6 in) over 9 days, compared to December's 97 mm (3.8 in) over 10 days. Humidity remains relatively similar, with October at 81% and December at 84%. For more details, you can check Mount Vernon weather in October.
In comparing the weather of December and November, December typically experiences cooler temperatures, with a minimum of -9°C (16°F) and an average of 6°C (44°F), compared to November's milder minimum of -4°C (24°F) and average of 10°C (50°F). The maximum temperatures also reflect a downward trend, peaking at 21°C (69°F) in December versus 25°C (77°F) in November. Precipitation is slightly higher in December, with 97 mm (3.8 in) falling over 10 days, compared to November's 84 mm (3.3 in) over 8 days. Humidity levels are quite similar, with December at 84% and November at 85%. For a detailed look at November's conditions, you can check the following link: Mount Vernon weather in November.
As December unfolds in Mount Vernon, temps swing dramatically compared to other months, showcasing a chill that dips well below freezing during the night. The average temperature hovers around a brisk 6°C (44°F), offering a stark contrast to the milder conditions experienced in autumn. Notably, this month also sees a significant amount of precipitation, with about 10 days marked by rainfall, coupled with a high humidity level of 84% that adds to the wintry feel. If you're curious about the broader climate trends, visit Mount Vernon Climate for more insights.