Last updated: August 28, 2025
September in Cat Ba, Vietnam showcases a warm and humid climate, with temperatures peaking at a maximum of 33°C (92°F) and averaging around 29°C (84°F). The month experiences considerable rainfall, totaling 312 mm (12.3 in) over 23 days, creating a lush, vibrant landscape. With humidity levels consistently around 82%, visitors should be prepared for a tropical experience. Despite the rain, Cat Ba's natural beauty shines, making it an enchanting destination for those willing to embrace the elements.
As September arrives in Cat Ba, Vietnam, the summer heat lingers, bringing warm and humid days ideal for outdoor exploration. The average temperature hovers around 29°C (84°F), with daytime highs reaching up to 33°C (92°F), while evenings remain comfortably warm with a minimum of 25°C (78°F). This slight dip from the sweltering months of July and August offers a welcome change, making it a prime time for beach outings and hiking among the stunning limestone karsts. September not only showcases the tail end of summer but also hints at the cooler months ahead, setting the stage for a lively yet enjoyable atmosphere in this breathtaking destination.
September in Cat Ba, Vietnam marks a significant transitional point in the rainfall patterns as the region sees a substantial precipitation amount of 312 mm (12.3 in) over 23 rainy days. This figure reflects a notable decrease from the previous month's peak of 567 mm (22.3 in) in August, yet still showcases the lingering monsoon influence typical of this season. As summer wanes, the frequency of rainy days also begins to taper off, hinting at the approaching drier months. This period sees lush landscapes nourished by persistent rainfall, creating a vibrant backdrop for both nature enthusiasts and travelers, while the overall trend indicates a gradual shift towards less intense but still frequent rain through the upcoming months.
As summer transitions to autumn in Cat Ba, Vietnam, September carries an average humidity of 82%. This figure reflects a slight decrease from the peak levels experienced during the sultry summer months of July and August, which saw humidity soar to 90% and 89%, respectively. However, September still maintains a notably high moisture content in the air, characteristic of the region's tropical climate. Following a pattern of elevated humidity from June through August, there is a gradual decline moving into October, where levels drop to 77%. This shift not only signals a change in the season but also hints at the easing of summer's sweltering grip, setting the stage for a more refreshing autumn in Cat Ba.
In September, Cat Ba, Vietnam, continues to experience an extreme UV Index of 13, necessitating a burn time of just 10 minutes for unprotected skin. This trend mirrors the intense UV levels observed throughout the summer months, from June to August, where the UV Index remained consistently at 13. As the region transitions into October, the UV Index drops slightly to 11, yet it still signifies high exposure levels. Those planning outdoor activities should remain vigilant, ensuring proper sun protection is utilized. For more details on the UV Index in this beautiful destination, visit Cat Ba UV Index.
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As summer gracefully transitions into autumn, September in Cat Ba, Vietnam offers a delightful blend of warmth and vibrant sunshine, boasting approximately 285 hours of sunlight. This marks a slight dip from the peak of summer, where May and June basked in over 300 hours, yet still reflects the region's remarkable luminosity. The sunlight is uniquely inviting during this time, providing the perfect backdrop for outdoor adventures and exploration. Following a trend of gradually decreasing sunshine hours, September's brightness prepares visitors for the approaching cooler months without sacrificing the charm of summer's glow. The weather is ideal for soaking in breathtaking views and immersing oneself in the natural beauty that Cat Ba has to offer.
In Cat Ba, Vietnam, September experiences a 27% chance of sunny weather, a modest figure that reflects the general trend of fluctuating sun exposure throughout the year. Following the hottest months of June and July, which see the lowest probabilities of sunshine at 15% and 25% respectively, September marks a slight recovery, though still below the yearly average. This month serves as a transitional period, hinting at the approaching fall, yet the likelihood of sunshine remains relatively low compared to the sunnier months of February and November, which boast chances of 59% and 50% respectively. Travelers should prepare for varying conditions, keeping in mind that while sunny days are possible, the weather can be unpredictable this time of year.
In Cat Ba, Vietnam, the rhythm of daylight throughout the year beautifully reflects the changing seasons. As spring arrives, March and April gift the island with longer days, extending to 12 hours of sunlight, which invites more outdoor adventures. The height of summer in May, June, and July showcases the peak daylight duration at 13 hours, perfect for basking in the sun and exploring lush landscapes. However, as we transition into late summer and early autumn, August and September experience a gentle decline, settling back to 12 hours of daylight. This pattern signals a shift towards shorter days, reminiscent of the cozy embrace of fall that follows, as October ushers in a further reduction to 11 hours. This gradual ebb and flow of daylight not only accentuates the natural beauty of Cat Ba but also sets the stage for the serene yet vibrant lifestyle found on the island.
As the summer heat gives way to the gentle embrace of autumn, September in Cat Ba, Vietnam, features a distinct drop in wind speed, averaging just 3.2 m/s (7 mph). This is notably the calmest month of the year, following a peak of 5.7 m/s (13 mph) in June. The winds gradually soften after the bustling summer, providing a serene backdrop for visitors seeking tranquility amidst the stunning landscapes. With the winds tapering off, this month sets the stage for a peaceful transition into the crisper October breezes, which pick up significantly to an invigorating 6.0 m/s (13 mph). Thus, September stands uniquely quiet as the winds whisper a gentle lull before the season's shift, inviting travelers to explore Cat Ba's natural beauty in a more contemplative atmosphere.
Weather in Cat Ba varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Cat Ba, focusing on differences in temperature, rainfall, humidity, and UV levels.
In September, the weather is characterized by hot and humid conditions, with average temperatures reaching 29°C (84°F) and a high of 33°C (92°F). The month experiences significant rainfall, totaling 312 mm (12.3 in) over 23 days, resulting in an average humidity level of 82%. In contrast, January offers a much cooler climate, with temperatures ranging from a minimum of 10°C (50°F) to a maximum of 24°C (75°F), and an average of 18°C (65°F). Precipitation drops drastically to just 34 mm (1.3 in) over 7 days, contributing to a lower humidity level of 66%. This stark difference in weather makes September feel sweltering and rainy, while January boasts a more temperate and drier atmosphere. For more details on January weather, you can check Cat Ba weather in January.
September and February present stark contrasts in weather patterns. In September, temperatures range from a minimum of 25°C (78°F) to a maximum of 33°C (92°F), with an average of 29°C (84°F), making it a hot and humid month with 312 mm (12.3 in) of precipitation over 23 days and a humidity level of 82%. Conversely, February offers much cooler conditions, with temperatures ranging from a minimum of 9°C (49°F) to a maximum of 24°C (75°F), and an average of 18°C (65°F). The month sees significantly less rainfall, with only 36 mm (1.4 in) over just 7 days and a lower humidity level of 71%. For those interested in more details, check out Cat Ba weather in February.
September and March present contrasting weather conditions. In September, temperatures are notably warmer, with a minimum of 25°C (78°F) and an average of 29°C (84°F), peaking at 33°C (92°F). This month is also characterized by high humidity at 82% and significant precipitation, averaging 312 mm (12.3 in) over 23 days. In contrast, March offers a cooler climate with minimum temperatures of 16°C (60°F), an average of 21°C (70°F), and a maximum of 27°C (80°F). Additionally, rainfall is much lower in March, totaling only 50 mm (2.0 in) over 13 days, with a humidity level of 69%. For a detailed look at weather specifics, visit Cat Ba weather in March.
September weather is noticeably warmer and more humid compared to April. With average temperatures reaching 29°C (84°F) and maximums soaring to 33°C (92°F), September experiences a higher minimum temperature of 25°C (78°F). Additionally, it sees significant precipitation, totaling 312 mm (12.3 in) over 23 days, making it one of the wetter months. In contrast, April features more moderate temperatures with an average of 24°C (75°F) and a maximum of 29°C (85°F), along with much lower precipitation of 84 mm (3.3 in) over just 11 days. The humidity in April is also more comfortable at 64%, compared to September's high humidity level of 82%. For more details, you can check Cat Ba weather in April.
September weather tends to be warmer and more humid compared to May, with average temperatures reaching 29°C (84°F) and humidity levels at 82%. In contrast, May offers slightly cooler temperatures, averaging 27°C (81°F) and a lower humidity level of 73%. Additionally, September experiences significantly more rainfall, totaling 312 mm (12.3 in) over 23 days, while May sees only 139 mm (5.5 in) of precipitation across 15 days. For a detailed look at the conditions in May, visit Cat Ba weather in May.
In comparing the weather of September and June, September tends to be slightly cooler, with an average temperature of 29°C (84°F), compared to June's 30°C (86°F). Both months experience high humidity, but September sees a bit more precipitation, with 312 mm (12.3 in) over 23 days, while June has 194 mm (7.6 in) over just 15 days. This makes September a wetter month, likely resulting in more rainy days compared to June's relatively dry conditions. For more detailed information on June weather, you can check out Cat Ba weather in June.
In comparing the weather between September and July, we see some noteworthy differences. Both months experience similar temperature ranges, with September exhibiting a minimum of 25°C (78°F) and an average of 29°C (84°F), while July has a slightly higher minimum temperature of 26°C (78°F) and an average of 29°C (85°F). Precipitation levels are quite high in both months, with September receiving 312 mm (12.3 in) over 23 days and July experiencing 325 mm (12.8 in) over 21 days. Humidity tends to be higher in July at 90% compared to September's 82%, indicating that July may feel slightly more oppressive. Overall, while both months are warm and wet, July's higher humidity and precipitation suggest it is the more intense of the two. For more detailed insights, you can check Cat Ba weather in July.
In comparing the weather of September and August, both months exhibit warm temperatures, with September experiencing a minimum of 25°C and an average of 29°C, slightly cooler than August's average temperature of 29°C and maximum of 34°C. While both months are similarly humid, September has a humidity level of 82%, slightly lower than August's 89%. Precipitation is also notably different, with September receiving 312 mm over 23 days, significantly less than August's 567 mm over 25 days. For a more detailed look into August's weather, you can visit Cat Ba weather in August.
September typically experiences higher temperatures with minimums around 25°C (78°F) and an average of 29°C (84°F), peaking at 33°C (92°F). In contrast, October brings cooler conditions, with minimum temperatures dropping to 19°C (67°F) and an average of 26°C (79°F), while maximum temperatures hover around 32°C (90°F). Rainfall is also slightly reduced in October, totaling 284 mm (11.2 in) over 17 days, compared to September's 312 mm (12.3 in) over 23 days. Additionally, humidity decreases from 82% in September to 77% in October, making October feel somewhat more comfortable. For more specific details on October conditions, check Cat Ba weather in October.
In September, the weather is typically hot and humid, with minimum temperatures around 25°C (78°F) and average highs reaching up to 33°C (92°F). The month is also marked by significant rainfall, averaging 312 mm (12.3 in) over 23 days, resulting in a humidity level of 82%.
In contrast, November offers a much more temperate climate, with minimum temperatures dropping to 14°C (57°F) and an average high of 28°C (83°F). Rainfall is considerably reduced, with only 53 mm (2.1 in) over 10 days, and humidity levels are lower at 72%. For more detailed information, check out Cat Ba weather in November.
September weather is characterized by warm temperatures, with average highs reaching 33°C (92°F) and a high humidity level of 82%. This month also sees significant rainfall, with 312 mm (12.3 in) of precipitation spread across 23 days, making it a rather wet period.
In contrast, December brings much cooler temperatures, with averages around 19°C (67°F) and highs peaking at 26°C (80°F). The amount of rainfall drops significantly, with only 42 mm (1.6 in) over just 8 days, and humidity decreases to 71%.
For more details, check out Cat Ba weather in December.
September in Cat Ba marks a transition into the wetter season, characterized by higher humidity levels and significant rainfall that distinguishes it from the drier months of summer. With frequent showers and an average temperature lingering around 29°C, outdoor activities may be more challenging than earlier in the year. However, the lush landscapes that emerge from this precipitation offer a stunning backdrop for exploration. For a deeper understanding of how September fits into the broader climate patterns of Cat Ba, visit Cat Ba Climate.