Last updated: August 21, 2025
In December, Tehran experiences a chilly climate marked by average temperatures hovering around 1°C (34°F), with daytime highs peaking at 13°C (55°F) and nighttime lows plummeting to a brisk -14°C (6°F). This month is characterized by 35 mm (1.4 in) of precipitation spread over roughly 7 days, contributing to the city's overall 70% humidity. As winter settles in, residents and visitors alike can expect a mix of cool, damp days, making warm clothing essential for outdoor activities.
As December unfolds in Tehran, temperatures begin to reflect the chill of winter. The month kicks off with minimums dropping to a brisk -14°C (6°F), setting a stark contrast to the milder days of fall. The average temperature hovers around 1°C (34°F), heralding a notable dip from November's more moderate climate. While daytime highs may reach up to 13°C (55°F), the cold nights strongly signal the heart of winter. This trend of decreasing temperatures not only illustrates a typical Iranian winter but also sets the stage for the even colder months ahead, marking December as a month of transition in Tehran's climate narrative.
In Tehran, December brings a notable shift in precipitation patterns, with 35 mm (1.4 in) of rain typically falling over 7 days. As the year draws to a close, this month experiences a mild upsurge compared to the drier summer months, where June and August recorded just a fraction of rainfall. While the November rains set the stage with 47 mm (1.9 in) over 8 days, December’s moderate precipitation helps sustain the region's moisture levels, balancing the drier spells earlier in the year. With winter approaching, this steady rainfall contributes to the city’s overall climate, hinting at a transition that will continue into the colder months ahead.
As the year draws to a close, December in Tehran showcases a notable increase in humidity, resting at 70%—a figure that mirrors the levels from January. This uptick follows a significant drop through the summer months, where July and August record the lowest humidity levels at 52% and 40% respectively. Interestingly, the fall months lead back up to November’s high of 72%, indicating a pattern of fluctuating moisture in the air as seasons change. Overall, December reflects a transitional humidity index, bridging the winter chill with echoes of a more humid autumn, providing a comfortable atmosphere as the city welcomes the new year.
In December, Tehran experiences a notable decline in UV exposure, with the UV Index dropping to 3, placing it in the moderate category. This decrease marks a shift from the higher indices seen in the preceding months, reflecting the onset of winter. The recommended burn time lengthens to 30 minutes, allowing residents to enjoy outdoor activities with more sun protection. As the year wraps up, the trend suggests a gradual easing of UV intensity, contrasting sharply with the extreme levels observed in the summer months. For more details on UV levels throughout the year, visit Tehran UV Index.
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In Tehran, December brings a welcoming dose of sunlight, with an average of 267 hours of sunshine illuminating the city. As the year transitions from the vibrant energy of summer to the cooler winter months, there’s a noticeable decline in daylight hours from the peak of 394 hours in July. However, December's sunshine still outshines the earlier winter months, maintaining a brisk vibrancy that hints at the city’s resilience. As the days grow shorter, the sun’s presence remains significant, offering a refreshing contrast to November’s gloom, which dipped to 256 hours. The steady decline from summer to winter showcases Tehran's climatic rhythm, while December’s brightness serves as a gentle reminder of the warmth that the sun consistently offers, even in the heart of winter.
In December, Tehran enjoys a 68% chance of sunny weather, marking a notable transition as the year draws to a close. While this figure is lower than the sun-drenched heights of mid-summer, such as June's impressive 94%, it still offers decent prospects for sunshine compared to earlier winter months like November, which stands at 57%. The data suggests a gradual shift towards sunnier days as the year progresses, with December providing a promising balance between the crisp winter air and accessible sunlight. Embracing the city's diverse climate, December represents a time when residents and visitors alike can expect a decent dose of bright weather before the winter chill deepens.
As the year winds down, December in Tehran ushers in a significant reduction in daylight, with sunlit hours dwindling to just 9 hours. This decline marks a stark contrast to the longer days experienced in earlier months, peaking at 14 hours during the summer. The transition from the bright days of May and June to the more subdued light of December reflects a rhythmic cycle of daylight duration that shapes the city's daily life. With each month, daylight diminishes gradually, creating a crisp winter atmosphere that invites both reflection and warmth as the year ends.
As December unfolds in Tehran, the average wind speed hovers around 1.6 m/s (4 mph), embracing the city with a gentle breeze as it transitions into winter. This slight dip from November’s 1.5 m/s (3 mph) signifies a trend of moderately increasing winds in the months leading up to winter, peaking in June and July at 2.2 m/s (5 mph). While the subsequent months witness a gradual decline, the winds of December maintain a consistent, soft presence, mirroring the city's cool, crisp atmosphere. The interplay of these seasonal shifts reflects not just a change in weather patterns, but also the rhythmic dance of Tehran's climate as it bids farewell to the year.
Weather in Tehran varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Tehran, focusing on differences in temperature, rainfall, humidity, and UV levels.
December and January weather exhibit notable differences, particularly in temperature. December generally sees milder conditions with average temperatures around 1°C (34°F), while January experiences colder weather, with an average temperature of -2°C (29°F). The minimum temperatures also shift, dropping from -14°C (6°F) in December to -16°C (3°F) in January. In terms of precipitation, December records 35 mm (1.4 in) over 7 days, whereas January sees a slightly higher precipitation of 39 mm (1.5 in) over 6 days, maintaining a constant humidity level of 70% throughout both months. For a more detailed look at the weather conditions in January, you can check this link: Tehran weather in January.
December and February exhibit notable differences in weather conditions despite their proximity in the winter season. December typically sees milder temperatures, with averages around 1°C (34°F), while February experiences colder minimums, dipping to -23°C (-9°F). Precipitation in February is also higher, totaling 66 mm (2.6 in) compared to December's 35 mm (1.4 in), and occurs over a greater number of days. Moreover, February’s humidity is slightly lower at 66%, contrasted with December’s 70%, contributing to a crisper feel in the air. For more detailed weather insights, check out Tehran weather in February.
December and March weather exhibit notable differences in temperature and precipitation. In December, temperatures can drop as low as -14°C (6°F), with an average around 1°C (34°F) and highs reaching 13°C (55°F). This month also sees about 35 mm (1.4 in) of precipitation over 7 days, accompanied by a humidity level of 70%. In contrast, March brings milder conditions, with temperatures ranging from a minimum of -8°C (17°F) to a comfortable maximum of 21°C (70°F), averaging around 5°C (42°F). Precipitation increases slightly to 58 mm (2.3 in) over 10 days, while humidity stays relatively stable at 68%. The transition from December to March reflects a shift towards warmer and wetter weather, showcasing the onset of spring. For more detailed insights, visit Tehran weather in March.
December and April present contrasting weather patterns. In December, temperatures can drop as low as -14°C (6°F), with an average of around 1°C (34°F) and highs reaching 13°C (55°F). The month is characterized by relatively high humidity at 70% and a total of 35 mm (1.4 in) of precipitation over about 7 days. In stark contrast, April sees milder conditions with minimum temperatures of -7°C (19°F) and an average of 11°C (53°F), peaking at 25°C (77°F). Although April experiences slightly more precipitation at 70 mm (2.8 in) over 11 days, the humidity drops to 62%, making it feel more comfortable. For a closer look at April's weather, check out Tehran weather in April.
In December, temperatures can drop significantly, with a minimum of -14°C (6°F) and an average around 1°C (34°F), making it a cold and often chilly month. The level of humidity reaches about 70%, contributing to the overall brisk feel, and precipitation occurs on approximately 7 days, totaling 35 mm (1.4 in). In contrast, May ushers in milder and more pleasant weather, with minimum temperatures around 4°C (40°F) and averages soaring to about 17°C (63°F), peaking at a warm 30°C (86°F). This month experiences slightly less precipitation, with 34 mm (1.3 in) spread over 6 days and a lower humidity of 64%. For more details on May weather, you can visit Tehran weather in May.
In December, temperatures can plummet to a minimum of -14°C (6°F), with an average around 1°C (34°F) and highs reaching only 13°C (55°F). The month sees about 35 mm (1.4 in) of precipitation over 7 days, coupled with a humidity level of 70%, creating a chilly and damp atmosphere. In stark contrast, June boasts much warmer conditions, starting with a minimum temperature of 10°C (51°F) and peaking at an average of 24°C (76°F), with maximum temperatures soaring to 33°C (92°F). The summer month enjoys minimal precipitation of just 4 mm (0.2 in) across 1 day and lower humidity at 62%, leading to a much drier and more pleasant climate. For more detailed information, visit Tehran weather in June.
December and July present contrasting weather patterns. In December, temperatures can plummet as low as -14°C (6°F), with an average of 1°C (34°F) and a maximum of 13°C (55°F). The month experiences about 35 mm (1.4 in) of precipitation over approximately 7 days, accompanied by a humidity level of 70%. In stark contrast, July boasts much warmer temperatures, with a minimum of 14°C (58°F) and an average of 27°C (81°F), peaking at 36°C (96°F). Precipitation is minimal, at only 6 mm (0.2 in) over just 1 day, and the humidity is lower at 52%. This distinct seasonal difference highlights the dramatic shifts in climate throughout the year. For more specific details about July weather, visit Tehran weather in July.
The weather in December contrasts sharply with that of August. In December, temperatures can plummet as low as -14°C (6°F), with an average around 1°C (34°F) and a maximum of 13°C (55°F), creating a chilly atmosphere. With 35 mm of precipitation over about 7 days and humidity levels at 70%, it feels quite damp and cold. In stark contrast, August boasts significantly warmer temperatures, with lows of 15°C (59°F), averages around 26°C (78°F), and highs reaching up to 35°C (95°F). Precipitation is minimal, with just 1 mm occurring on average, and the air is much drier, with humidity at 40%. For more details on the warm weather in August, check out Tehran weather in August.
December brings a stark contrast to the weather experienced in September. In December, temperatures range from a minimum of -14°C (6°F) to a maximum of 13°C (55°F), with an average of just 1°C (34°F), while September offers much warmer conditions, with temperatures ranging from 10°C (50°F) to a pleasant maximum of 33°C (91°F) and an average of 22°C (72°F). Precipitation is also significantly higher in December, with 35 mm (1.4 in) falling over 7 days, compared to the virtually dry September, which records only 4 mm (0.2 in) and sees no rainy days at all. Moreover, the humidity in December sits at 70%, creating a damp chill, while September's lower humidity level of 45% contributes to a more comfortable atmosphere. For more regional insights, you can check Tehran weather in September.
Comparing the weather of December and October reveals a stark contrast in temperatures and conditions. In December, temperatures can drop to a chilling low of -14°C (6°F) with an average of just 1°C (34°F), while October enjoys milder conditions with lows around 1°C (34°F) and an average high of 14°C (57°F). Precipitation is slightly higher in December at 35 mm (1.4 in) over 7 days, compared to October's 31 mm (1.2 in) over 6 days. Additionally, December has a higher humidity level at 70%, making the cold feel more intense, whereas October's humidity stands at a more comfortable 61%. For more detailed insights, check out Tehran weather in October.
In December, temperatures significantly drop, with a minimum of -14°C (6°F) and an average of 1°C (34°F), contrasted with November's milder temperatures that range from a minimum of -8°C (17°F) to an average of 6°C (43°F). While December experiences less precipitation at 35 mm (1.4 in) over 7 days, it is still notable compared to November, which sees 47 mm (1.9 in) over 8 days. Additionally, humidity levels remain relatively consistent between the two months, with December at 70% and November at 72%. For a more detailed look at weather patterns, check out Tehran weather in November.
As December rolls into Tehran, the city's climate transforms into a chillier embrace compared to the rest of the year. With temperatures dipping significantly, the maximum daytime warmth is replaced by crisp, cold nights, making cozy layers a must for any outdoor plans. While the month experiences moderate precipitation, it’s notably lower than the wetter spring months, lending a quieter atmosphere as the city gears up for winter's full arrival. The humidity hangs around a comfortable 70%, creating a distinct contrast to the hot, arid conditions of summer. For a deeper understanding of how Tehran's December compares to other months, explore more at Tehran Climate.