Last updated: April 22, 2025
December in Saint John, Canada presents a fascinating blend of winter's chill and coastal charm. The average temperature hovers around -1°C (31°F), with maximums reaching a mild 14°C (57°F) and dipping to a brisk -18°C (-1°F) at the lowest. This month witnesses significant precipitation, totaling 142 mm (5.6 in) over 12 days, creating a festive, albeit wet, atmosphere. With an average humidity level of 82%, residents and visitors alike can expect a true winter experience, where the beauty of snow-laden landscapes meets the invigorating maritime air.
In Saint John, Canada, December ushers in the deep chill of winter, with temperatures dipping to a brisk minimum of -18°C (0°F) and averaging around -1°C (31°F). This month typically sees a slight pause before the harshest winter extremes, with a maximum temperature reaching up to 14°C (57°F). Compared to the preceding months, December's cold marks a significant drop; however, it’s considerably milder than the depths of January and February, when temperatures plummet even further. As the holiday season approaches, the sharp, crisp air becomes a hallmark of the Canadian winter, making frosty mornings and cozy evenings a delightful contrast for residents and visitors alike.
December in Saint John, Canada, marks a significant transition in weather patterns as the year draws to a close. With precipitation reaching 142 mm (5.6 in) over 12 rainy days, December contributes to the wintery ambiance of the city. This amount is slightly lower than November's hefty 184 mm (7.3 in), which recorded the highest rainfall of the year, yet it still showcases a notable increase compared to preceding months like June and July. The trudge toward winter is evident as temperatures drop and precipitation shifts increasingly towards snow. As the final month of the year, December encapsulates the trend of rising precipitation seen throughout the fall, setting a wet stage for the upcoming winter months.
In Saint John, Canada, December marks a continuation of the city’s high humidity levels, averaging around 82%. This figure is consistent with the month-to-month humidity trends observed throughout the year. From January to December, humidity fluctuates between 78% and 84%, with the winter months typically hovering at the upper end of this range. Notably, December sits right in the middle of this spectrum, mirroring the relatively high levels seen in the preceding months of November and July. It's clear that Saint John's coastal climate contributes to persistent humidity, providing a unique atmosphere that defines the city's winter months.
In December, Saint John, Canada, experiences a low UV Index of 2, resulting in a burn time of about 45 minutes. This decrease in UV exposure marks a continuation of the trend seen since summer, where the index peaked at 10 in June and 9 in May, primarily categorized as very high. As the year draws to a close, residents can enjoy outdoor activities with minimal risk of sunburn, contrasting sharply with the higher indices of the spring and summer months. This seasonal shift emphasizes the importance of monitoring UV levels throughout the year for safe sun exposure. For more details on the UV Index in Saint John, visit Saint John UV Index.
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In December, Saint John, Canada, experiences a gentle transition as the year winds down, offering 153 hours of sunshine. While this is a dip compared to the bright, sun-drenched days of mid-summer, it signals the gradual return to longer days following the depths of winter. The trend shows a steady increase from a low of 127 hours in January, climbing to a peak with 312 hours in August, highlighting the vibrant summer months. December's sun, though less prominent than in the peak summer, still bathes the city in a warm glow, making it a cozy time for reflection and festive celebrations before the fresh promise of brighter days in the New Year.
In December, Saint John, Canada experiences a 33% chance of sunny weather, which reflects a slight uptick in optimism compared to the earlier winter months. This percentage stands out amidst a generally low likelihood of sunshine during the colder season, with January and February dropping to just 29% and 28%, respectively. As we transition from November's 41% chance of sun, December signals a shift towards steadily darker days. However, it still offers more sunshine than the peak summer months of July and August, where clear skies are only expected about 19% and 29% of the time. Overall, while December may not promise an abundance of sunny days, it certainly provides a glimmer of hope for those seeking warmth amid the winter chill.
As the year winds down in Saint John, Canada, December brings the shortest daylight duration at just 8 hours. This fading light marks a contrast to the gradual increase in daylight seen from January to June, where the days stretch to their longest at 15 hours during the summer months of June and July. Following this peak, daylight begins to retreat, leading to a gentle decline through the autumn and into early winter. The transition from the vibrant 14 hours of daylight in May to the subdued 8 hours in December reflects the natural rhythm of the seasons, inviting a cozy introspection as the year closes.
As December wraps Saint John in its chilly embrace, the average wind speed picks up to 6.1 m/s (14 mph), marking a notable increase compared to the preceding months. After a relatively calmer summer, where winds dipped as low as 4.1 m/s in July, the trend shifts noticeably as autumn arrives. November introduces a brisk 5.6 m/s, setting the stage for December’s stronger gusts. This rise in wind speed reflects the seasonal transition, with winter's approach bringing more invigorating breezes that can be felt through the city’s streets. As the wind whips through the harbor and along the coastal paths, it carries with it a sense of excitement and anticipation for the holiday season, making December a dynamic month in Saint John's weather tapestry.
The weather in Saint John 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 Saint John and find detailed weather information for every month.
December and January showcase notable differences in weather conditions. In December, the temperatures range from a minimum of -18°C (1°F) to a maximum of 14°C (57°F), with an average of -1°C (31°F) and a total precipitation of 142 mm (5.6 in) over 12 days, resulting in a humidity level of 82%. January, on the other hand, tends to be slightly colder with minimum temperatures dropping to -22°C (-8°F) and an average of -4°C (26°F). The maximum temperature is a bit lower at 13°C (56°F), alongside reduced precipitation levels of 107 mm (4.2 in) over 10 days and a slightly higher humidity of 83%. For more detailed information, you can visit Saint John weather in January.
In December, temperatures in Saint John typically range from a minimum of -18°C (1°F) to a maximum of 14°C (57°F), with an average temperature of -1°C (31°F). The month sees considerable precipitation, totaling 142 mm (5.6 in) over 12 days, and humidity levels hover around 82%. In contrast, February tends to be slightly colder, with minimum temperatures reaching -20°C (-4°F) and a maximum of 10°C (50°F), leading to an average of -3°C (26°F). Precipitation decreases to 112 mm (4.4 in) while maintaining the same frequency of 12 days of precipitation, but humidity rises slightly to 84%. For more details on February weather, visit Saint John weather in February.
December and March share similar average temperatures, often hovering around -1°C (31°F), but their temperature extremes reveal notable differences. In December, the cold can plunge as low as -18°C (2°F), while March sees slightly milder conditions, with a minimum of -17°C (2°F) and a maximum of 11°C (52°F). Precipitation in December is more abundant, totaling 142 mm (5.6 in) over 12 days, compared to March's 88 mm (3.5 in) over 10 days. Despite both months having a humidity level of 82%, March typically feels less harsh than December. For more specific details on March’s weather, you can check Saint John weather in March.
December and April present quite different weather experiences. In December, temperatures can plunge as low as -18°C (1°F), with an average of -1°C (31°F) and highs reaching 14°C (57°F). The month is characterized by significant precipitation, totaling 142 mm (5.6 in) over 12 days, and humidity levels around 82%. In contrast, April sees a milder climate, with minimum temperatures of -5°C (23°F) and an average of 4°C (40°F), peaking at 13°C (55°F). While the precipitation is slightly lower at 129 mm (5.1 in) over 13 days, humidity is similarly high at 80%. For more details, check out Saint John weather in April.
December and May exhibit strikingly different weather patterns. In December, temperatures can plunge as low as -18°C (1°F), with an average around -1°C (31°F) and highs reaching 14°C (57°F). The month typically experiences about 142 mm (5.6 in) of precipitation over 12 days, coupled with high humidity levels at 82%. In contrast, May is much milder, with temperatures ranging from a minimum of 1°C (33°F) to a pleasant maximum of 20°C (68°F) and an average of 9°C (48°F). Precipitation decreases slightly to 117 mm (4.6 in) over the same number of days, accompanied by slightly lower humidity at 78%. For more details, check out Saint John weather in May.
December and June present starkly contrasting weather conditions. In December, temperatures can plunge to a minimum of -18°C (1°F), with an average around -1°C (31°F) and a maximum of 14°C (57°F). The month typically experiences significant precipitation, totaling 142 mm (5.6 in) over 12 days, accompanied by a high humidity level of 82%. In contrast, June sees milder conditions with a minimum of 4°C (39°F), an average of 13°C (56°F), and a pleasant maximum of 21°C (71°F). Precipitation in June is slightly lower at 110 mm (4.3 in) across 11 days, but the humidity remains constant at 82%. For more information about Saint John's June weather, visit Saint John weather in June.
December and July present starkly contrasting weather conditions. December experiences frigid temperatures, with a minimum of -18°C (1°F) and an average of -1°C (31°F), while July offers much milder conditions, with temperatures ranging from a minimum of 11°C (51°F) to a maximum of 22°C (72°F). Precipitation is more abundant in December, totaling 142 mm (5.6 in) over 12 days, compared to July's 92 mm (3.6 in) spread across 13 days. Additionally, while the humidity remains relatively similar at 82% in December and 84% in July, the overall experience of these months is drastically different. For more details, you can check Saint John weather in July.
December and August in Saint John present a striking contrast in weather conditions. In December, temperatures can plunge as low as -18°C (1°F), with an average of -1°C (31°F) and highs reaching only 14°C (57°F). The month is also marked by significant precipitation, averaging 142 mm (5.6 in) over 12 days, accompanied by high humidity levels of 82%. In contrast, August enjoys much milder weather, with minimum temperatures around 11°C (53°F), average temperatures of 17°C (63°F), and maximums hitting 23°C (74°F). Precipitation in August is lower, at 89 mm (3.5 in) over 10 days, yet still maintains the same humidity level of 82%. For more detailed information on the weather during this warmer month, you can visit Saint John weather in August.
December and September present stark contrasts in weather conditions. In December, temperatures plunge significantly, ranging from a frigid minimum of -18°C (1°F) to a maximum of 14°C (57°F), while the month averages around -1°C (31°F). With 142 mm (5.6 in) of precipitation over 12 days, this winter month is characterized by chilly, damp conditions and persistent humidity at 82%. In contrast, September offers a much milder climate, with temperatures varying from a minimum of 7°C (45°F) to a pleasant maximum of 22°C (73°F), averaging at 15°C (59°F). Although it sees a slightly lower precipitation level of 108 mm (4.3 in) over 10 days, humidity remains at 82%, creating a comfortable atmosphere. For more details, you can explore Saint John weather in September.
December weather in Saint John is characterized by significantly colder temperatures, with a minimum of -18°C (1°F) and an average of -1°C (31°F), compared to October's milder range, which sees a minimum of 0°C (33°F) and an average of 11°C (52°F). While both months experience similar amounts of precipitation, with December receiving 142 mm (5.6 in) and October at 123 mm (4.8 in), December's chill is further accentuated by higher snowfall potential. Additionally, both months have a relative humidity of 82%, creating a damp and cold feeling in December, whereas October's conditions are often more refreshing. For a detailed look at October's conditions, visit Saint John weather in October.
In comparing the weather between November and December, it's clear that December experiences colder temperatures overall. While November's average temperature hovers around 5°C (40°F), December sees a significant drop with an average of -1°C (31°F). The minimum temperatures also reflect this change, with November’s lows at -12°C (10°F) compared to December's chilling -18°C (-1°F). Precipitation is slightly less in December, totaling 142 mm (5.6 in) over 12 days, compared to November's 184 mm (7.3 in) over 14 days. Humidity levels remain fairly consistent, with December at 82% and November at 84%. For more details, you can refer to Saint John weather in November.
As December arrives in Saint John, the weather takes a significant turn, ushering in colder temperatures and a higher likelihood of precipitation compared to the milder months that preceded it. With an average temperature hovering around -1°C, the chill sets in, contrasting sharply with more temperate fall conditions. The month is characterized by increased humidity levels and a notable number of precipitation days, which can lead to a wintry atmosphere across the city. Those venturing out must prepare for the crisp bites of winter while enjoying the beauty of seasonal changes. For a deeper dive into the region's climate nuances, explore our dedicated page on Saint John Climate.