Last updated: January 18, 2025
Tehran, Iran, experiences a diverse climate characterized by a blend of BSh (semi-arid), Csa (Mediterranean), and Dsa (continental) Köppen-Geiger classes. The city endures a wide temperature range, with minimum temperatures plummeting to -23°C (-9°F) in the coldest month of February, while summer peaks can soar to a scorching 45°C (114°F) in July. On average, Tehran enjoys a temperate climate with an average annual temperature of 16°C (61°F), making it a unique intersection of extremes that shapes its weather patterns and influences daily life.
Tehran's temperature patterns exhibit significant seasonal variation, characterized by cold winters and hot summers. In the winter months of January and February, temperatures plummet to minimums around -23°C (-9°F), with average daily lows near 2°C (35°F) to 4°C (39°F). As spring approaches, temperatures begin to rise, peaking in March and April, where daytime highs can reach 35°C (95°F). By late spring and into summer, from May to August, Tehran experiences its warmest temperatures, with maximums soaring to 45°C (114°F) in July and August, while average temperatures hover around 30°C (86°F). The transition into autumn sees a gradual cooling, with October and November showcasing average temperatures of 16°C (62°F) and 8°C (48°F), respectively, before winter returns, bringing back the chill as temperatures drop again in December. This cycle highlights Tehran's contrasting climatic extremes and the stark shifts from one season to another.
The climate data for the regions around Tehran reveals some interesting patterns. In both Tajrish and Tehran, temperatures can drop to a minimum of -23°C (-9°F) in February, while both areas reach a maximum of 36°C (96°F) in July, as detailed in their respective links: monthly temperatures in Tajrish and monthly temperatures in Tehran. In contrast, Rey experiences slightly milder winter temperatures with a minimum of -15°C (6°F) in February and can reach a scorching 42°C (109°F) in July, according to its link: monthly temperatures in Rey.
Tehran's precipitation patterns reveal a distinct seasonal distribution, with the majority of rainfall occurring during the late fall and winter months. January and February lead the charge, accumulating 31 mm (1.2 in) and 51 mm (2.0 in) of precipitation, respectively, often attributed to cold fronts and weather systems. March and April follow closely behind with 48 mm (1.9 in) and 54 mm (2.1 in), as spring showers help nurture the region's lush transitions. The frequency of rainy days peaks during these months, averaging about 7 to 8 days of rain, ensuring sufficient moisture before the drier summer months set in.
As summer arrives, precipitation in Tehran notably declines, with June, July, and August recording minimal rainfall, all around 6 mm (0.2 in) or less, and often featuring no rainy days at all. This drastically reduced precipitation continues into early autumn, with September and October seeing only 4 mm (0.2 in) and 24 mm (1.0 in), respectively. The onset of winter in November brings a revival of rain, with 44 mm (1.7 in) of precipitation occurring over about 7 days. The yearly cycle highlights Tehran's Mediterranean climate influences, marked by a wet season primarily concentrated in the cooler months and a pronounced dry period in summer.
Tehran experiences a notable increase in sunshine duration as the seasons transition from winter to summer, reflecting a clear pattern of increasing daylight. In January, the city enjoys 226 hours of sunshine, which gradually rises to 270 hours in February. As spring unfolds, sunshine hours accelerate with March recording 320 hours, peaking in April at 336 hours. May further enhances this trend, reaching 382 hours as the weather warms up, and by the time summer arrives, sunshine hits its zenith in June and July with 395 hours and 396 hours, respectively. This period of abundant sunlight is crucial for agricultural practices and contributes to the overall vibrancy of the city during its warmest months.
As summer transitions to autumn, sunshine hours begin to decline, although September still retains a substantial 343 hours of sunlight. October witnesses a further decrease to 312 hours, signaling the onset of cloudier days. November and December experience the least sunshine, with only 258 hours and 269 hours respectively, as shorter days and potential winter weather manifest. This seasonal cycle highlights Tehran's distinct climate characteristics, showcasing a vibrant summer filled with sunlight contrasted by the cooler, less luminous winter months, making it crucial for residents and visitors to adapt their activities according to the shifting light throughout the year.
Tehran's UV Index demonstrates a striking seasonal pattern, escalating dramatically from winter into summer. In January, the UV Index stands at 5, categorized as moderate, allowing for a burn time of 30 minutes when unprotected. As winter transitions into spring, February sees a rise to 6, moving into the high exposure category with a reduced burn time of 25 minutes. By March and April, the UV Index peaks at 10, marking a shift to a very high risk for skin damage, where exposure should be limited to just 15 minutes. This trend underscores the increasing intensity of ultraviolet radiation as the days grow longer and sunnier.
The peak UV Index occurs during the summer months, where values soar to 13 in May and June, classified as extreme, allowing only 10 minutes for safe sun exposure. Even July and August maintain high levels at 12 and 11, respectively, reinforcing the need for sun protection during this period. In contrast, September and October witness a decline to 10 and 8, respectively, but still retain a very high risk category. Later in the year, November sees a drop back to a moderate UV Index of 5, and December further declines to 4, allowing for longer exposure times of 30 minutes. Overall, Tehran's seasonal fluctuation in UV Index highlights the importance of sun safety, particularly during the peak summer months when risks are at their highest.
UV Risk Categories
Tehran experiences a dynamic shift in daylight duration throughout the year, starting from the shorter days of winter. In January and February, residents enjoy around 10 hours of daylight. As spring approaches, daylight begins to increase, culminating in March with approximately 11 hours of sunlit hours. By April, the transition into longer days becomes more pronounced, with daylight extending to 13 hours, and reaching a peak of 14 hours in both May and June. This gradual lengthening of daylight not only enhances the vibrancy of the city but also positively impacts outdoor activities and overall well-being.
During the summer months of July and August, daylight remains consistent at about 14 hours, providing ample time for outdoor pursuits and community events. However, as autumn sets in, a gradual reduction of daylight is observed—September sees 12 hours followed by a decline to 11 hours in October. The shortening of days continues into winter, with November dropping back to 10 hours and December further reducing to just 9 hours. This cyclical pattern of daylight duration emphasizes the seasonal changes in Tehran, revealing how the length of daylight influences lifestyle and activities throughout the year.
Damavand, Iran experiences a diverse climate characterized by cold winters and warm summers. January temperatures can drop to -22°C (-7°F), while July highs reach up to 32°C (90°F). Precipitation peaks in spring, especially in April with 72 mm (2.8 in), while summer months see significantly less rainfall, averaging only 4 mm (0.2 in) in August. The area enjoys ample sunshine, with June and July offering the most sunlight at 395 hours each. For more detailed climate information, visit Damavand climate.
Rey, Iran experiences a diverse climate with significant temperature variations throughout the year. Winters are cold, with January lows reaching -12°C (11°F) and an average of 4°C (40°F), while summers see high temperatures peaking at 42°C (109°F) in July. Precipitation is heaviest in the winter months, particularly February and November, while the summer months are typically dry, with August receiving no rainfall. The area enjoys abundant sunshine, especially from May to July, with over 390 hours of sunlight each month. For more detailed information, visit Rey climate.
Tajrish, Iran experiences a diverse climate characterized by cold winters and warm summers. January sees minimum temperatures drop to -16°C (3°F) and average highs of 12°C (53°F), while July reaches maximums of 36°C (96°F). Precipitation is highest in early spring, peaking at 70 mm (2.8 in) in April, followed by a significant decrease during the summer months. The region enjoys abundant sunshine, with July having the most hours at 394. For more detailed climate information, visit Tajrish climate.
Tehran experiences a varied climate with cold winters and hot summers. January and February are the coldest months, with average temperatures plunging to around -2°C (29°F) and 0°C (32°F), respectively, and notable precipitation of up to 66 mm (2.6 in). Spring brings milder temperatures, peaking in May at an average of 17°C (63°F), while summer months of June through August can see highs reaching up to 36°C (96°F) with minimal rainfall. The city enjoys abundant sunshine, particularly in summer, with the highest recorded hours in July at 394. For more details, visit Tehran climate.
In summary, Tehran's climate exhibits distinct seasonal variations in temperature, precipitation, sunshine duration, UV Index, and daylight. The city's winters are characterized by cold temperatures and reduced sunshine, while summers bring intense heat and prolonged daylight, combined with high UV exposure that necessitates protective measures. The patterns of precipitation highlight a wet season during the colder months and a dry spell in summer, which aligns with the region's Mediterranean influences. Understanding these climatic elements is essential for residents and visitors alike, as they navigate the diverse weather conditions throughout the year and engage in activities that harmonize with the shifting seasons. This comprehensive overview emphasizes the importance of adapting to Tehran's unique climate to ensure both safety and enjoyment in this vibrant urban environment.