December Weather in Ottawa, Canada

Last updated: April 22, 2025

December in Ottawa, Canada, showcases a dramatic winter landscape where temperatures oscillate from a maximum of 14°C (58°F) down to a chilling minimum of -29°C (-20°F). The average temperature hovers around -5°C (22°F), setting the stage for a frosty atmosphere. With 80 mm (3.2 in) of precipitation spread over 12 days, the city's weather often manifests in the form of snow, blanketing the streets in white. Coupled with a high humidity level of 89%, Ottawa's December invites both residents and visitors to embrace the beauty and challenges of a quintessential Canadian winter.

December Temperature in Ottawa

In December, Ottawa experiences a notable chill, with temperatures dipping to a minimum of -29°C (-20°F), while the average settles around -5°C (22°F). This month marks the onset of winter, showcasing a stark contrast to the more moderate temps of the preceding months. As Ottawa transitions from late autumn, the maximum temperature reaches only 14°C (58°F), hinting at the cold grip of the season. The significant drop from November's warmer averages is indicative of winter's arrival, setting the stage for snowy landscapes and festive holiday cheer in the Canadian capital.

December Weather in Ottawa: Daily Temperature Highs, Lows, and Averages

The chart illustrates December temperature patterns in Ottawa, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec161827415564706860483322
Data source: Temperature data for Ottawa generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

December Precipitation in Ottawa

In December, Ottawa experiences a relatively consistent pattern of precipitation, receiving 80 mm (3.2 in) over 12 days. This amount marks a slight decrease from the previous month's 97 mm, yet follows the trend of winter’s gradual onset, where colder temperatures often lead to a mix of rain and snow. The December precipitation aligns closely with January's average, suggesting that the region is well into its winter season, characterized by similar rainfall patterns. As the year closes, residents can expect a landscape transformed by winter's embrace, with December serving as a reminder of the cozy charm brought on by the season's unique weather.

December Precipitation Trends in Ottawa

The chart displays monthly precipitation patterns in Ottawa, with values for each month alongside December's data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how December's conditions compare to those of other months.
JanFebMarAprMayJunJulAugSepOctNovDec7681871121179811494791329780
Data source: Precipitation data for December generated using information from the Copernicus Climate Change Service.
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December Humidity in Ottawa

In December, Ottawa experiences a notable increase in humidity, with levels reaching 89%, just a notch below the preceding month of November at 88%. This rise reflects a trend observed throughout the winter months, where January and February maintain a high 93% humidity, creating a chilly but moist atmosphere. As the year progresses into the spring and summer, humidity typically decreases, with May showing the most comfortable levels at 75%. However, as the colder months resume, December signals the return of high humidity, contributing to the city’s distinctively crisp and sometimes damp winter climate. The transition from the fall's drop to winter's embrace highlights Ottawa's seasonal variability and its atmospheric nuances.

December Average Humidity in Ottawa

This chart illustrates the average monthly humidity levels in Ottawa, with December's data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, allowing you to see how December's humidity levels compare to other months.
JanFebMarAprMayJunJulAugSepOctNovDec93%93%86%82%75%68%69%67%72%83%88%89%
Data source: Humidity data for December generated using information from the Copernicus Climate Change Service.

December UV Index in Ottawa

In Ottawa, December brings a notable dip in the UV Index, registering at 2, which falls into the low exposure category. This trend marks a significant contrast to the summer months, where values soared into the very high range. With a burn time of 45 minutes, residents can enjoy outdoor activities with minimal risk of sunburn. Interestingly, as the year progresses from winter to summer, the UV Index fluctuates dramatically, peaking at 9 during the sunnier months, before tapering back down to these cooler, safer levels in December. For more details on daily UV trends, visit Ottawa UV Index.

Maximum UV Index Levels in Ottawa for December

The chart shows the monthly maximum UV Index (UVI) for Ottawa in December, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues.
JanFebMarAprMayJunJulAugSepOctNovDec245899887532
Data source: Ottawa December UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

December Sunshine in Ottawa

In December, Ottawa basks in approximately 127 hours of sunshine, marking a subtle dip as the city transitions into the depths of winter. This decline follows a steady upward trend seen through the earlier months, peaking in July with a remarkable 348 hours of golden rays. The sunshine hours gradually increase from the stark 111 hours in January, lifting through the spring and early summer, then gently tapering off with the onset of autumn. December’s daylight serves as a quiet reminder of the crisp beauty of winter, contrasting with the summer’s vibrant warmth while still delivering fleeting moments of sunshine amidst the chill. As the year winds down, each hour of sun becomes a cherished treasure in Ottawa’s winter landscape.

Monthly Sunshine Duration in Ottawa: December Highlighted

The December sunshine duration represents the total number of hours Ottawa experiences direct sunlight during the month of December, excluding cloudy or obstructed periods. This chart compares the sunshine duration of December with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec111h156h235h227h279h314h348h315h267h190h142h127h
Data source: Ottawa December Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Ottawa During December

In Ottawa, December tends to usher in a notable dip in sunny days, with only a 19% chance of sun. This is sharply contrasted by the increasingly bright months that precede it; for instance, October and November show higher probabilities of sunlight at 29% and 40%, respectively. The sunshine likelihood gradually climbs through the winter months, peaking in March at 44%. As we compare December's figures to those of both the prior months and the upcoming spring, it's evident that this chilly month stands out as one of the cloudiest of the year, setting the stage for the cooler, darker days typical of Ottawa's winter season.

Percentage of Sunny Days in December in Ottawa

The chart illustrates the percentage of sunny days in Ottawa throughout the year, with December highlighted. It highlights the variation in sunshine across each month and provides an overview of the typical frequency of sunny days, offering insights into how often Ottawa experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec27%35%44%36%44%34%35%43%39%29%40%19%
Data source: Ottawa December chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Ottawa in December

As December sets in, daylight in Ottawa, Canada dips to a modest 8 hours, continuing the trend of decreasing sunlight that begins in late autumn. This reduction is part of a natural ebb and flow, where the city experiences a gradual decline from the 14 hours of daylight in May to a brief low before the days start to lengthen again. Interestingly, while January and November also boast 9 hours of daylight, December's shorter days highlight the starkness of winter's approach. However, this decrease sets the stage for the return of longer days, as the sun’s journey begins to ascend in January, offering a glimmer of light at the end of the winter tunnel.

Average Daylight Hours in Ottawa for December

The chart illustrates the variation in daylight duration in Ottawa throughout the year, with December highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec9h 9m10h 23m11h 57m13h 33m14h 55m15h 36m15h 13m14h12h 28m10h 52m9h 28m8h 45m
Data source: Ottawa daylight hours, calculated by summing the hours between sunrise and sunset for each day.

December Winds in Ottawa

As December unfolds in Ottawa, Canada, the wind begins to pick up, with an average speed of 3.5 m/s (8 mph), marking a noticeable increase compared to the preceding months. This shift is particularly intriguing when viewed against a backdrop of generally stable wind patterns throughout the year, where speeds hover around 2.4 to 3.2 m/s. Interestingly, December's winds not only signal the approach of winter but also represent a transition from the milder breezes of autumn, which often linger in the earlier months. The colder air masses start to assert their presence, invigorating the city with the crispness associated with the season. As Ottawa prepares for the festive holiday atmosphere, this December wind serves as a reminder of the changing landscape, ushering in the snowy days ahead while inviting residents to bundle up and embrace the charm of the winter season.

Average December Wind Speed in Ottawa

The chart displays monthly wind speed patterns in Ottawa, with values for each month shown alongside December's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how December's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec2.92.93.83.22.93.12.62.43.02.83.03.5 m/s
Data source: Ottawa December wind data, generated using information from the Copernicus Climate Change Service.

How December Weather in Ottawa Compares to Other Months

The weather in Ottawa 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 Ottawa and find detailed weather information for every month.

December and January exhibit notable differences in weather patterns. In December, temperatures range from a minimum of -29°C (-20°F) to a maximum of 14°C (58°F), with an average of -5°C (22°F). It experiences a total precipitation of 80 mm (3.2 in) over 12 days, accompanied by a humidity level of 89%. In contrast, January brings even colder conditions, with temperatures plummeting to a minimum of -32°C (-26°F) and an average of -9°C (16°F), while the maximum reaches only 10°C (50°F). January sees slightly less precipitation at 76 mm (3.0 in) over 9 days and a higher humidity of 93%. For more detailed insights about January's weather, visit Ottawa weather in January.

In December, temperatures can plunge as low as -29°C (-20°F), with an average of -5°C (22°F) and a maximum temperature of 14°C (58°F), showcasing the potential for both frigid and relatively mild days. The month sees around 80 mm (3.2 in) of precipitation over approximately 12 days, coupled with high humidity levels averaging 89%. In contrast, February's weather is only slightly less severe, with minimum temperatures of -27°C (-16°F) and an average of -8°C (18°F), reaching a maximum of 11°C (53°F). Precipitation remains similar at 81 mm (3.2 in) over the same number of days, but humidity increases to 93%. For a more detailed look at what to expect, visit Ottawa weather in February.

In December, temperatures in Ottawa can drop to a chilling minimum of -29°C (-20°F), with an average of -5°C (22°F) and a maximum of 14°C (58°F). The month typically sees around 80 mm (3.2 in) of precipitation over 12 days, accompanied by high humidity levels at 89%. In contrast, March offers slightly milder conditions, with minimum temperatures around -24°C (-12°F) and an average of -3°C (27°F), peaking at a more pleasant 20°C (69°F). Precipitation is slightly higher at 87 mm (3.4 in), also spread over 12 days, but humidity drops slightly to 86%. For more detailed information, check Ottawa weather in March.

In December, temperatures in Ottawa can plunge as low as -29°C (-20°F), with an average chilling at around -5°C (22°F) and a maximum reaching a mild 14°C (58°F). The month typically sees about 80 mm (3.2 in) of precipitation over approximately 12 days, accompanied by high humidity levels of 89%. In contrast, April brings a noticeable shift in weather, with minimum temperatures rising to -12°C (10°F) and average temperatures hovering around 5°C (42°F). The maximum can soar to 27°C (81°F), making it a much warmer month overall. April also sees an increase in precipitation, totaling 112 mm (4.4 in) over the same number of days, but with slightly lower humidity at 82%. For more information on what to expect, check out Ottawa weather in April.

December and May exhibit stark contrasts in weather conditions. In December, temperatures can plunge as low as -29°C (-20°F), with an average around -5°C (22°F) and a maximum of 14°C (58°F). The month is characterized by high humidity (89%) and about 80 mm (3.2 in) of precipitation over 12 days, often falling as snow. In contrast, May offers a much milder climate, with temperatures ranging from a low of -3°C (26°F) to a scorching high of 35°C (95°F). With an average temperature of 13°C (56°F) and 117 mm (4.6 in) of precipitation spread over 14 days, the humidity is comparatively lower at 75%. For a more detailed look at May weather, visit Ottawa weather in May.

December and June present stark contrasts in weather patterns. In December, temperatures can plummet to a minimum of -29°C (-20°F) with an average of -5°C (22°F), while highs reach a milder 14°C (58°F). This month is characterized by high humidity at 89% and 80 mm (3.2 in) of precipitation over about 12 days, often resulting in a snowy landscape. In contrast, June brings a much warmer atmosphere, with temperatures ranging from a minimum of 2°C (36°F) to an average of 18°C (65°F) and maximums soaring to 32°C (91°F). While June experiences slightly more precipitation at 98 mm (3.9 in) over 13 days, the humidity is noticeably lower at 68%. For more details, you can check Ottawa weather in June.

December and July in Ottawa present a stark contrast in weather. December experiences frigid temperatures, with a minimum of -29°C (-20°F) and an average of -5°C (22°F), while July boasts a much milder climate, with temperatures ranging from a minimum of 8°C (47°F) to a high of 35°C (96°F). Precipitation is fairly balanced between the two months, with December receiving 80 mm (3.2 in) over 12 days and July slightly higher at 114 mm (4.5 in) during the same number of days. Humidity levels also differ significantly, with December's humidity averaging 89%, contrasting with July's more comfortable 69%. For a closer look at Ottawa's July weather, check out Ottawa weather in July.

December and August present stark contrasts in weather. December is characterized by frigid temperatures, with lows reaching -29°C (-20°F) and an average of around -5°C (22°F), while August enjoys much milder conditions, with minimums of 7°C (45°F) and an average of 20°C (68°F). Precipitation levels are relatively close, with December receiving 80 mm (3.2 in) over 12 days and August slightly higher at 94 mm (3.7 in) over 13 days. Humidity plays a significant role as well; December sees a damp 89%, making the cold feel even more intense, while August is more comfortable at 67%. For a closer look at weather specifics in August, visit Ottawa weather in August.

In comparing the weather of December and September, it's clear that the two months present stark contrasts. December experiences much colder temperatures, with minimums plummeting to -29°C (-20°F) and an average temperature of -5°C (22°F), while September boasts a much milder climate, showcasing a minimum of 0°C (31°F) and an average of 15°C (60°F). Precipitation levels are similar, with December receiving 80 mm (3.2 in) across 12 days and September slightly less at 79 mm (3.1 in) over 11 days. Additionally, December has a higher humidity level at 89%, compared to September's 72%. For further insights, you can explore Ottawa weather in September.

When comparing the weather in December and October, a stark contrast emerges. December experiences significantly lower temperatures, with a minimum of -29°C (-20°F) and an average around -5°C (22°F), while October sees milder conditions, with temperatures ranging from a minimum of -6°C (22°F) to a maximum of 27°C (81°F). Additionally, October tends to be wetter, with 132 mm (5.2 in) of precipitation compared to December's 80 mm (3.2 in), although both months witness precipitation on 12 days. Humidity is relatively high in both months, with December at 89% and October at 83%. For more insights into October's climate, check out Ottawa weather in October.

In December, temperatures are notably colder, with a minimum of -29°C (-20°F) compared to November's minimum of -19°C (-2°F). The average temperature in December drops further to -5°C (22°F), while November has a milder average of 0°C (33°F). Despite December's slightly lower overall precipitation at 80 mm (3.2 in) over 12 days, it still feels more wintry, with a maximum temperature of 14°C (58°F) compared to November's warmer peak of 22°C (71°F). Humidity remains relatively high in both months, with December at 89% and November at 88%. For more detailed insights, you can explore Ottawa weather in November.

Compare Ottawa's Climate with Cities Worldwide

Conclusion: What to Expect From December Weather in Ottawa

As December descends upon Ottawa, the city transforms into a winter wonderland, marking a stark departure from the milder months. The chill sets in with an average temperature hovering around -5°C (22°F), contrasting sharply against the much warmer autumn days. With an occasional peak of 14°C (58°F), the brief warmth is a fleeting reminder of fall. However, the season's hallmark is more pronounced; with minimum temperatures plunging to -29°C (-20°F), residents brace for the cold. Combined with 80 mm (3.2 in) of precipitation over about 12 days, the humidity spikes to a frosty 89%, making the air feel particularly crisp. This unique blend of cold temperatures and snowfall sets December apart, inviting both challenges and the enchanting beauty of winter. As you navigate through this chilly month, explore more about the diverse climate patterns throughout the year at Ottawa Climate.