December Weather in Sylhet, Bangladesh

Last updated: August 21, 2025

In December, Sylhet, Bangladesh experiences a remarkable blend of cool temperatures and high humidity, making it a unique winter destination. With a maximum temperature reaching 29°C (85°F) and an average of 19°C (66°F), the days are pleasantly warm, while nighttime lows can drop to a refreshing 10°C (50°F). Despite a modest precipitation level of 40 mm (1.6 in) over just 2 days, the region remains lush and vibrant, thanks in part to the remarkable 86% humidity. This combination of climatic factors creates a cozy atmosphere, inviting visitors to explore the natural beauty and cultural richness of Sylhet during this enchanting month.

December Temperature in Sylhet

In December, Sylhet, Bangladesh experiences a delightful shift in temperatures as the region transitions into winter. The month begins with a minimum temperature of 10°C (50°F), providing a crispness that is refreshing after the warmer months. Daytime highs reach a comfortable 29°C (85°F), while the average temperature hovers around 19°C (66°F), making it an inviting time for outdoor activities and exploration. This month showcases a noticeable drop from the previous months, highlighting the departing warmth that characterizes the region from May to November. As temperatures begin to stabilize in December, visitors can enjoy the mild climate, perfect for immersing themselves in the lush landscapes and vibrant culture of Sylhet.

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

The chart illustrates December temperature patterns in Sylhet, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Sylhet, December typically has an average temperature of {2}°C ({3}°F), with highs reaching up to {4}°C ({5}°F) and lows dropping to around {6}°C ({7}°F).
JanFebMarAprMayJunJulAugSepOctNovDec636773778082828383807365
Data source: Temperature data for Sylhet generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

December Precipitation in Sylhet

In December, Sylhet, Bangladesh experiences a noticeable decline in precipitation compared to the preceding months, with 40 mm (1.6 inches) of rainfall recorded over just 2 days. This month marks a transition from the intense monsoon season, where averages soar above 800 mm, to a much drier period. The precipitation is a stark contrast to the heavy rains of June through August, which can see up to 895 mm. As the year winds down, festive activities commence amid the cooling temperatures, creating a vibrant atmosphere accompanied by the relatively mild rainfall that marks December in this lush region.

December Precipitation Trends in Sylhet

The chart displays monthly precipitation patterns in Sylhet, 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. In Sylhet, December typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec6291175035208168957494662472040
Data source: Precipitation data for December generated using information from the Copernicus Climate Change Service.
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December Humidity in Sylhet

In December, Sylhet, Bangladesh experiences a notable continuation of its humid climate, with an 86% humidity level that reflects the tail end of the monsoon season. This figure is slightly lower than the peak humidity observed in the summer months of July and August, which soar to an oppressive 91% and 90% respectively. However, it remains higher than the drier months of April and March, where humidity dips to 47% and 53%. Overall, the trend indicates a gradual transition from the high humidity of mid-year to a slightly drier atmosphere as the region heads toward winter. This persistent humidity contributes to the lush greenery that Sylhet is renowned for, offering a vibrant landscape even as the year comes to a close.

December Average Humidity in Sylhet

This chart illustrates the average monthly humidity levels in Sylhet, with December’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In December, average humidity in Sylhet is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec76%69%53%47%79%86%91%90%89%89%88%86%
Data source: Humidity data for December generated using information from the Copernicus Climate Change Service.

December UV Index in Sylhet

In December, Sylhet, Bangladesh experiences a UV Index of 6, categorizing it as high and allowing for a burn time of 25 minutes. This marks a notable decline from the extreme levels seen in the summer months, particularly July, which peaks at a UV Index of 14. The transition from the extreme conditions in mid-year to a more temperate December highlights the seasonal variations that characterize the region, making it essential for residents and visitors alike to adjust their sun protection strategies accordingly. As winter approaches, the sun still can be powerful, so staying informed is crucial for enjoying outdoor activities safely. For more detailed information on UV levels throughout the year, visit Sylhet UV Index.

Maximum UV Index Levels in Sylhet for December

The chart shows the monthly maximum UV Index (UVI) for Sylhet 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. In December, the maximum UV index in Sylhet typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec6791013131413131086
Data source: Sylhet 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 Sylhet

In December, Sylhet, Bangladesh basks in a delightful 296 hours of sunshine, continuing a trend of bright skies consistent since October. This month marks a fitting close to a year characterized by fluctuating sun hours, peaking in March at an impressive 333 hours. Following the intensity of summer, where sunlight dipped to 222 hours in July, December's golden days showcase the region's resilience as it transitions from lush monsoons to cool winter breezes. With only a slight variance from the previous month, December's sunlight serves as a gentle reminder that even in the heart of winter, Sylhet remains a haven for sun-seekers and nature lovers alike.

Monthly Sunshine Duration in Sylhet: December Highlighted

The December sunshine duration represents the total number of hours Sylhet 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.
JanFebMarAprMayJunJulAugSepOctNovDec245h288h333h308h311h253h222h247h262h301h296h296h
Data source: Sylhet December Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Sylhet During December

In December, Sylhet, Bangladesh experiences a 67% chance of sunny weather, marking a notable shift as the region transitions from the rainier months of June through September, where sunshine is scarce. Following the peak of 82% in November, December offers a promising balance between pleasant weather and the onset of winter. This trend reflects a gradual decline in sunny days as the year closes, yet it still provides ample opportunities for outdoor activities before the significant drop in sunshine during the early months of the year. The festive atmosphere of December, coupled with its relatively high likelihood of sunny days, makes it an attractive time to visit Sylhet.

Percentage of Sunny Days in December in Sylhet

The chart illustrates the percentage of sunny days in Sylhet 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 Sylhet experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec87%85%75%68%40%7%4%5%19%58%82%67%
Data source: Sylhet December chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Sylhet in December

In Sylhet, Bangladesh, the daylight duration experiences a subtle yet noticeable rhythm throughout the year. Beginning with a modest 10 hours in January, the days gradually lengthen, peaking at 13 hours from May through July. This period of extended sunlight is accompanied by a vibrant and lush landscape typical of the region's monsoon season. As summer gives way to autumn, daylight begins to retreat, returning to 12 hours in August and September, before tapering down again to 11 hours in October and back to 10 hours in both November and December. The cyclical dance of daylight not only marks the changing seasons but also enhances the beauty of Sylhet's natural surroundings, creating a captivating atmosphere year-round.

Average Daylight Hours in Sylhet for December

The chart illustrates the variation in daylight duration in Sylhet throughout the year, with December highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec10h 45m11h 18m12h12h 44m13h 20m13h 38m13h 29m12h 57m12h 16m11h 32m10h 55m10h 36m
Data source: Sylhet daylight hours, calculated by summing the hours between sunrise and sunset for each day.

December Winds in Sylhet

As December arrives in Sylhet, Bangladesh, the average wind speed slightly increases to 1.5 m/s (3 mph), marking a subtle shift as the year draws to a close. This gentle breeze, consistent with the mild winds observed throughout the months preceding it, reflects the region's typically calm climate. Notably, the winds remain remarkably uniform, with most months averaging around 1.4 m/s, offering a pleasing consistency that enhances the serene atmosphere of the area. As the year transitions into winter, this stable wind pattern invites locals and visitors alike to appreciate the tranquil beauty of Sylhet's landscapes, perfectly complemented by the rhythmic rustling of leaves and the crisp December air.

Average December Wind Speed in Sylhet

The chart displays monthly wind speed patterns in Sylhet, 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.
JanFebMarAprMayJunJulAugSepOctNovDec1.41.51.81.51.41.41.41.41.31.31.41.5 m/s
Data source: Sylhet December wind data, generated using information from the Copernicus Climate Change Service.

How December Weather in Sylhet Compares to Other Months

Weather in Sylhet varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Sylhet, focusing on differences in temperature, rainfall, humidity, and UV levels.

December and January display some notable differences in weather patterns. In December, temperatures range from a minimum of 10°C (50°F) to a maximum of 29°C (85°F), with an average of 19°C (66°F) and a higher humidity of 86%. There is also more precipitation in December, totaling 40 mm (1.6 in) over just two days. In contrast, January sees slightly cooler temperatures, with a minimum of 6°C (44°F), an average of 17°C (63°F), and a maximum of 29°C (84°F). The month is drier, yielding only 6 mm (0.2 in) of precipitation over a single day and lower humidity at 76%. For more detailed insights on January weather, you can visit Sylhet weather in January.

In December, the weather is relatively warm with temperatures ranging from a minimum of 10°C (50°F) to a maximum of 29°C (85°F). It experiences higher humidity at 86%, coupled with 40 mm (1.6 in) of precipitation over two days. In contrast, February sees slightly cooler temperatures, with minimums of 9°C (49°F) and maximums reaching 30°C (86°F). The month has lower humidity at 69% and less precipitation, totaling 28 mm (1.1 in) across three days. For a detailed look at February's weather, you can visit Sylhet weather in February.

In December, the weather is mild, with temperatures ranging from a minimum of 10°C (50°F) to a maximum of 29°C (85°F), averaging around 19°C (66°F). The month experiences relatively low precipitation, with just 40 mm (1.6 in) over 2 days, and humidity remains high at 86%. In contrast, March brings warmer conditions, with temperatures ranging from a minimum of 12°C (54°F) to a maximum of 34°C (93°F), averaging 23°C (74°F). However, this month sees significantly higher rainfall, totaling 117 mm (4.6 in) across 9 days, and a drop in humidity to 53%. For more details on the weather in March, check out Sylhet weather in March.

In December, the weather is relatively mild, with temperatures ranging from a comfortable 10°C (50°F) to a warm 29°C (85°F). The month sees minimal rainfall, with only 40 mm (1.6 in) over just two days, and a high humidity level of 86%. In contrast, April experiences significantly warmer temperatures, with a minimum of 17°C (63°F) and a scorching maximum of 35°C (96°F). However, this month is also marked by substantial rainfall, totaling 503 mm (19.8 in) over 19 days, and much lower humidity at 47%. For more detailed insights, check out Sylhet weather in April.

December and May exhibit striking differences in weather patterns. December boasts milder temperatures with a minimum of 10°C (50°F) and an average of 19°C (66°F), while the maximum can reach up to 29°C (85°F). This month experiences relatively low precipitation of 40 mm (1.6 in) over just 2 days and maintains high humidity at 86%. In contrast, May is significantly warmer, featuring a minimum temperature of 20°C (68°F) and an average of 27°C (80°F), peaking at a scorching 36°C (98°F). However, May is much wetter, with precipitation soaring to 520 mm (20.5 in) across 27 days, and humidity decreasing slightly to 79%. For more detailed insights into May weather, you can check out Sylhet weather in May.

When comparing the weather in December and June, it's clear that there are significant differences. December features milder temperatures, with a minimum of 10°C (50°F) and a maximum of 29°C (85°F), averaging around 19°C (66°F). The month also experiences relatively low precipitation, totaling just 40 mm (1.6 in) over approximately 2 days, with humidity levels around 86%. In contrast, June is much warmer, with temperatures ranging from a minimum of 23°C (73°F) to a scorching maximum of 35°C (96°F), averaging about 28°C (82°F). However, June is characterized by heavy rainfall, with a staggering 816 mm (32.1 in) of precipitation over 29 days. The humidity remains high at 86%, creating a distinctly tropical atmosphere. For more specific details about June weather, you can refer to Sylhet weather in June.

December and July present contrasting weather experiences. In December, temperatures range from a minimum of 10°C (50°F) to a maximum of 29°C (85°F), with an average of 19°C (66°F) and relatively low humidity at 86%. Precipitation is light, totaling just 40 mm (1.6 in) over two days. In stark contrast, July sees much warmer temperatures, with a minimum of 23°C (73°F) and a scorching maximum of 37°C (99°F), averaging around 28°C (83°F). This month is characterized by significant rainfall, accumulating to 895 mm (35.2 in) over 30 days, and higher humidity levels at 91%. For more details on the weather conditions, you can refer to Sylhet weather in July.

December and August present contrasting weather patterns in terms of temperature and precipitation. In December, temperatures range from a minimum of 10°C (50°F) to a maximum of 29°C (85°F), with an average of 19°C (66°F). This month experiences relatively low precipitation, totaling about 40 mm (1.6 in) over just 2 days and an average humidity of 86%. In stark contrast, August boasts much warmer temperatures, with minimums around 25°C (76°F) and maximums reaching up to 37°C (99°F), averaging 28°C (84°F). However, the month is characterized by heavy rainfall, accumulating 749 mm (29.5 in) across 30 days, coupled with a humidity level of 90%. For more detailed insights, refer to Sylhet weather in August.

In December, the weather tends to be milder with temperatures ranging from a minimum of 10°C (50°F) to a maximum of 29°C (85°F) and an average of 19°C (66°F). Precipitation is relatively low at 40 mm (1.6 in) over just 2 days, and humidity remains high at 86%. In contrast, September experiences much hotter conditions, with temperatures ranging from a minimum of 24°C (75°F) to a maximum of 37°C (98°F) and an average of 28°C (83°F). However, this month is notably wetter, receiving 466 mm (18.3 in) of rain over 26 days, while humidity is slightly higher at 89%. For more detailed information, you can check Sylhet weather in September.

When comparing the weather in December and October, notable differences emerge. December experiences milder temperatures, with a minimum of 10°C (50°F) and a maximum of 29°C (85°F), leading to an average of 19°C (66°F). In contrast, October boasts much warmer temperatures, with a minimum of 18°C (64°F) and a maximum of 36°C (98°F), resulting in an average of 27°C (80°F). Additionally, October sees significantly higher precipitation, with 247 mm (9.7 in) over 16 days, while December has only 40 mm (1.6 in) over just 2 days. Humidity levels in both months are relatively high, with December at 86% and October at 89%. For more details, check Sylhet weather in October.

In December, temperatures range from a minimum of 10°C (50°F) to a maximum of 29°C (85°F), with an average of 19°C (66°F), making it cooler compared to November, which sees temperatures starting at a minimum of 14°C (57°F) and reaching up to 32°C (89°F) with an average of 23°C (73°F). While December has a slightly lower humidity level at 86% compared to November's 88%, it also experiences a reduction in precipitation, totaling 40 mm (1.6 in) over 2 days compared to November's 20 mm (0.8 in) over 3 days. For a more detailed look at November's weather, check out Sylhet weather in November.

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Conclusion: What to Expect From December Weather in Sylhet

In December, Sylhet experiences a delightful transition as temperatures cool down, with an average around 19°C, offering a pleasant respite compared to the warmer months. With a maximum of 29°C during the day and a minimum dipping to 10°C at night, it’s an ideal time for outdoor adventures. The region also enjoys a significant reduction in rainfall, averaging only 40 mm across just two days, while humidity remains high at 86%. This unique blend of cooler air and lower precipitation makes December a refreshing contrast to the wet, steamy months earlier in the year. For an in-depth understanding of weather patterns throughout the year, visit Sylhet Climate.