Last updated: February 24, 2025
December in Hyannis, United States, brings a chilly atmosphere with temperatures ranging from a maximum of 15°C (60°F) to a brisk minimum of -12°C (11°F), averaging around 4°C (40°F). This month typically sees 12 days of precipitation, accumulating to about 136 mm (5.4 in), contributing to a notably humid environment with levels hovering around 80%. Residents and visitors alike should prepare for a wet and cold December, making it a time for cozy indoor activities and festive celebrations.
In December, Hyannis experiences a noticeable dip in temperatures, with the minimum plunging to -12°C (11°F), while the average hovers around a brisk 4°C (40°F). As the month progresses, the maximum temperature reaches a moderate 15°C (60°F), signaling a chillier transition from the fall months. Compared to the milder November, December's cooler patterns emphasize the onset of winter, bridging the gap between the lingering autumnal warmth and the deep freeze of January. This contrast highlights the seasonal shift, encouraging residents and visitors to prepare for the cold while still enjoying the occasional warmer day.
In December, Hyannis experiences 136 mm (5.4 in) of precipitation over approximately 12 days, signaling a shift towards the wetter winter months. This amount is slightly lower than October's peak of 175 mm (6.9 in) but remains relatively high compared to the earlier months of the year, indicating a steady pattern of moisture as the year closes. Notably, December's rainfall is on par with April's and slightly higher than November's, showcasing a consistent trend of significant winter precipitation that contributes to the region's seasonal transition. As the cold sets in, residents can expect a mix of rain and the potential for snow, especially as winter progresses.
In Hyannis, United States, the December humidity remains relatively high at 80%, mirroring the levels seen in both November and the cold winter months of January and February, which consistently hover around 84%. This trend suggests that as the year winds down, residents of Hyannis can expect moist air that carries over from the autumn season. Notably, after a slight decline to 75% in the warmer months of May through October, humidity begins to rise again as temperatures drop, indicating a seasonal pattern where colder months bring increased moisture. Overall, December's humidity reflects a return to the higher averages characteristic of New England winters, creating a chilly yet damp atmosphere as the year concludes.
In Hyannis, December brings a noticeable decline in the UV Index, dropping to 2, which falls into the low exposure category. This lower UV rating allows for a more forgiving burn time of 45 minutes, making it an ideal time for outdoor activities without the immediate concern of sunburn. This trend of diminishing UV levels is consistent as the year progresses; starting from a moderate index in January, the UV levels peak during the summer months before tapering down in the fall and early winter. Such fluctuations highlight the importance of staying informed about the UV Index, especially for those keen on enjoying the beauty of Hyannis. For more details, check out Hyannis UV Index.
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As December unfolds in Hyannis, United States, a gentle decline in sunshine hours marks the transition into winter. With 165 hours of sunlight, the month reflects a notable decrease from the sunshine peaks of summer, where July and June bask in over 300 hours each. Interestingly, December's light follows a trend of diminishing daylight that begins from the glorious bloom of May with 298 hours, gently tapering off throughout the fall. Despite this seasonal shift, the charm of Hyannis remains, as the crisp air and festive spirit provide a delightful contrast to the quieter days of sunlight. As the year wraps up, the community embraces the cozy ambiance, making the most of the beautiful, albeit fewer, hours of winter sunshine.
In December, the likelihood of sunny weather in Hyannis, United States, dips to 28%, making it one of the cloudier months of the year. This trend is consistent as we transition from the more optimistic 52% chance of sun in November, with October and September also showcasing relatively higher probabilities of sunshine at 44% and 49% respectively. As winter approaches, the chances of clear skies decrease more noticeably, with December wrapping up the year at one of its lowest points. This pattern hints that while the earlier months may offer glimpses of brightness, December is likely to be marked by overcast skies, encouraging cozy indoor activities rather than sunny outings.
In Hyannis, United States, the December daylight duration mirrors that of January, both offering about 9 hours of sunlight each day. As the year progresses, there's a notable increase in daylight, starting from 9 hours in January to a peak of 15 hours by June, reflecting the gradual shift towards longer days in the warmer months. Following this peak, daylight begins to wane, with July and August showcasing 14 and 13 hours respectively, before tapering off to 12 hours in September and 11 hours in October. The months of November and December then settle back to the shorter daylight hours, giving a cyclical feel to the changing seasons, as the sunlight diminishes alongside the temperature. This pattern underscores the rhythmic nature of seasonal shifts, marking both the chill of winter and the promises of brighter days ahead.
As December rolls into Hyannis, the wind picks up slightly, averaging 6.6 m/s (15 mph), a trend that mirrors the consistent breezes of the preceding months. After a gradual decline from the summer’s gentle 4.8 m/s (11 mph) in August to the more robust gusts seen at the start of winter, December's winds maintain a steady pace akin to those in October and November. This stability suggests that as the year closes, the winds turn slightly brisker, providing a crisp atmosphere that perfectly complements the scenic coastal charm of Cape Cod in winter. The relatively moderate wind speed also hints at a lingering warmth from the autumn months, inviting residents and visitors alike to enjoy beach walks and outdoor activities amidst the invigorating sea air.
The weather in Hyannis 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 Hyannis and find detailed weather information for every month.
December and January exhibit some notable differences in weather patterns. December tends to have slightly milder temperatures, with an average of 4°C (40°F) compared to January's average of 2°C (36°F). The minimum temperatures in January dip lower, reaching -14°C (6°F), while December's minimum is -12°C (11°F). Precipitation in December is also higher, at 136 mm (5.4 in) over 12 days, compared to January's 94 mm (3.7 in) across 10 days. Additionally, January experiences a slight increase in humidity, averaging 84% versus December's 80%. For more specific insights into January's climate, check out Hyannis weather in January.
December and February exhibit similar cold temperature ranges, with both months experiencing minimum lows of around -12°C (11°F) and -12°C (10°F), respectively. However, December tends to be slightly warmer on average, with temperatures reaching an average of 4°C (40°F) compared to February's average of 2°C (36°F). Precipitation levels are also comparable, with December receiving 136 mm (5.4 in) over 12 days, slightly higher than February's 123 mm (4.8 in) over the same number of days. Humidity levels are marginally higher in February at 84%, compared to December's 80%. For more information, check out Hyannis weather in February.
In December, temperatures range from a chilly minimum of -12°C (11°F) to a more moderate maximum of 15°C (60°F), with an average temperature hovering around 4°C (40°F). The month experiences considerable precipitation, totaling 136 mm (5.4 in) over about 12 days, and the humidity level is relatively high at 80%. In contrast, March sees slightly milder weather with temperatures varying from a minimum of -9°C (16°F) to a maximum of 13°C (56°F), averaging about 3°C (38°F). The precipitation levels decrease to 118 mm (4.7 in) across 10 days, while humidity rises marginally to 82%. For a detailed look at the climate during March, you can check Hyannis weather in March.
December and April display notably different weather patterns, reflecting the transition from winter to spring. December experiences colder temperatures, with minimums reaching as low as -12°C (11°F) and an average of 4°C (40°F), while April is milder, starting at a minimum of 1°C (33°F) and averaging 7°C (46°F). Both months receive similar amounts of precipitation—136 mm (5.4 in) in December and 137 mm (5.4 in) in April—though December has slightly fewer rainy days (12) compared to April's 13. Additionally, the humidity levels are comparable, with December at 80% and April at 79%. For those interested in more specific details about April weather, you can visit Hyannis weather in April.
In comparing the weather conditions of December and May, we see a stark contrast in temperatures and overall climate. December experiences much colder temperatures, with a minimum of -12°C (11°F) and an average peak of only 15°C (60°F), while May showcases a milder range, featuring a minimum of 5°C (41°F) and a comfortable maximum of 21°C (70°F). Precipitation is relatively similar in both months, with December receiving 136 mm (5.4 in) over 12 days and May slightly less at 119 mm (4.7 in) during the same number of days. Additionally, December's higher humidity level of 80% lends a chill to the air, compared to the more pleasant 75% humidity in May. For more detailed insights, you can check Hyannis weather in May.
December and June present stark contrasts in weather patterns. In December, temperatures can drop as low as -12°C (11°F), with an average of around 4°C (40°F) and highs reaching just 15°C (60°F). The month is also characterized by significant precipitation, totaling 136 mm (5.4 in) over approximately 12 days, accompanied by high humidity levels averaging 80%. In contrast, June enjoys milder temperatures with a minimum of 10°C (51°F), an average of 17°C (63°F), and maximums soaring to 24°C (76°F). Additionally, June receives less precipitation, around 91 mm (3.6 in) across 10 days, with humidity slightly lower at 78%. For more specific details, visit Hyannis weather in June.
December and July present strikingly different weather patterns. In December, temperatures can plunge to a minimum of -12°C (11°F), with an average of 4°C (40°F) and a maximum reaching 15°C (60°F). The month sees significant precipitation with 136 mm (5.4 in) over approximately 12 days, contributing to a humidity level of 80%. In contrast, July offers a much warmer climate, with minimum temperatures of 16°C (61°F) and averages around 21°C (71°F), peaking at 29°C (84°F). The precipitation in July is lighter at 83 mm (3.3 in) over about 9 days, and the humidity is slightly lower at 76%. For a more detailed view of the summer weather, check out Hyannis weather in July.
When comparing the weather in December and August, it's evident that they offer vastly different climates. December experiences colder temperatures, with a minimum of -12°C (11°F) and an average of around 4°C (40°F), while August enjoys milder conditions, with temperatures ranging from a minimum of 16°C (61°F) to an average of 22°C (72°F). Precipitation is more frequent in December, occurring on 12 days and totaling 136 mm (5.4 in), compared to August's 8 days of rain and 82 mm (3.2 in). Additionally, December features higher humidity levels at 80%, while August maintains a slightly lower humidity of 76%. For more details on August weather specifics, you can check Hyannis weather in August.
In December, the weather is significantly colder, with temperatures ranging from a chilly min of -12°C (11°F) to a max of 15°C (60°F) and an average of 4°C (40°F). In contrast, September enjoys milder conditions, with temperatures typically between 13°C (56°F) and 25°C (78°F), averaging around 19°C (67°F). Additionally, December experiences higher precipitation levels of 136 mm (5.4 in) over 12 days, while September sees slightly less at 118 mm (4.7 in) over 10 days. Humidity levels are also higher in December at 80%, compared to 75% in September. For more details on September weather, you can visit Hyannis weather in September.
When comparing the weather in December to October, it's clear that December is significantly colder, with minimum temperatures plunging to -12°C (11°F) compared to October's milder minimum of 4°C (39°F). The average temperature in December is around 4°C (40°F), whereas October enjoys a more comfortable average of 15°C (59°F). Precipitation levels are also noteworthy: December sees about 136 mm (5.4 in) of rainfall over 12 days, while October has slightly higher precipitation at 175 mm (6.9 in), with the same number of rainy days. Humidity levels in December average around 80%, higher than October's 75%, contributing to a chillier and damp atmosphere. For more details on October weather, you can visit Hyannis weather in October.
In comparing the weather between November and December, it's clear that December tends to be colder, with temperatures ranging from a minimum of -12°C (11°F) to a maximum of 15°C (60°F), whereas November sees milder temperatures from a low of -6°C (21°F) to a high of 19°C (66°F). Additionally, December experiences more precipitation, averaging 136 mm (5.4 in) over 12 days, compared to November's 102 mm (4.0 in) over 10 days. Despite the increased rainfall in December, both months maintain a consistent humidity level of 80%. For more details on November weather patterns, you can visit Hyannis weather in November.
As December settles into Hyannis, the weather takes a noticeable turn, offering a blend of chilly temperatures and increased precipitation that sets it apart from the milder months of the year. This month typically brings cooler average temperatures, with maximums rarely reaching above 15°C, contrasting sharply with the warmth of summer. Additionally, December is marked by higher humidity levels and frequent rainy days, contributing to a dampness that softens the coastal landscape. The overall atmosphere encapsulates the transition into winter, making it a unique and reflective time to experience the charm of Hyannis. For more insights on climate patterns, visit Hyannis Climate.