Climate and monthly weather forecastHa Long, Vietnam

Climate and monthly weather forecast
The climate of Ha Long
Situated in Vietnam, Ha Long sees a predominantly humid subtropical climate with a dry winter (Cwa), as classified by the Köppen climate classification system. Ha Long's climate demonstrates variations across the year with regard to temperature, humidity, sunlight, and rainfall. The city experiences a high average temperature range from 13.7°C (56.7°F) to 34.1°C (93.4°F), and a relative humidity fluctuating between 71% and 83% throughout the year.Rainfall is a key feature of Ha Long's climate. The total rainfall varies significantly from 15mm (0.59") to 317mm (12.48") over the course of a year. The region's wettest month is August, with an average rainfall of 317mm (12.48"), while February registers the least amount of rainfall at 15mm (0.59"). Concurrently, the rainy days range from 12.8 to 28.3 days per month, with the maximum rainy days in July and the minimum in February. This displays a clear variation in the annual pattern of precipitation.
Days in Ha Long generally receive approximately 10.9 to 13.4 hours of daylight. The sunniest period is around June, having about 9.9 hours of sunshine per day, which decreases to the lowest around December with about 4.9 sunlight hours. On an average, the city experiences an ultraviolet (UV) index that oscillates from 4 to 7, indicating variable levels of potential skin damage from the sun's UV radiation.
The best time to visit Ha Long
Given the climate conditions and weather patterns, the best time to visit Ha Long is in the warmer months from April to June. During this period, the average high temperature ranges from 26.8°C (80.2°F) to 34.1°C (93.4°F), offering plenty of sunlight hours from 7.8 hours to 9.9 hours. The city also witnesses environment-friendly UV index between 6 and 7, enabling vibrant outdoor tourist activities.The worst time to visit Ha Long
The worst time to visit Ha Long is during the rainy season, from July to September, when the city encounters the highest rainfall of the year - from 255mm (10.04") to 317mm (12.48") over approximately 28.3 to 26.8 days. High humidity levels, peaking at 83%, paired with heavy rainfall can turn the city into a less enjoyable destination for travelers.Spring weather in Ha Long
Spring in Ha Long, from March to May, observes a gradual increase in temperature from 26.8°C (80.2°F) to 33.3°C (91.9°F). Rainfall too witnesses an increment from 36mm (1.42") in March to 163mm (6.42") in May. Nevertheless, the region observes increased daylight from 12 hours to 13.1 hours and comfortable visibility of 9km (5.6mi) through the entirety of Spring.Summer weather in Ha Long
Summer, spanning from June to August, dominates the climate of Ha Long with the highest temperature readings for the year. While June begins with a peak average high of 34.1°C (93.4°F), it gradually drops to 31.9°C (89.4°F) by August. Although rainfall is significant, from 224mm (8.82") to 317mm (12.48"), the UV index remains consistently high at 7, thereby maintaining the summer charm.Autumn weather in Ha Long
In Autumn, September to November, Ha Long experiences a cooling trend with the high temperature scaling down from 30.9°C (87.6°F) to 25.9°C (78.6°F). Rainfall decreases substantially from 232mm (9.13") to 34mm (1.34"), making way for clearer sky views. The UV index also lowers from 6 to 5, enhancing the overall natural beauty of autumn in Ha Long.Winter weather in Ha Long
Winter in Ha Long, from December to February, is characterized by lower temperatures varying between 14.1°C (57.4°F) and 23.8°C (74.8°F), coupled with reduced sunlight hours of 4.9 to 5. Weather during this season remains dry, as rainfall levels drop from 25mm (0.98") in December to 15mm (0.59") in February. Despite being the coldest time of the year, Winter in Ha Long offers a distinct climatic charm with its placid and serene environment.Weather in January
January ushers in a fresh year with mild temperatures in Ha Long, Vietnam. The high and low temperatures tend to hover around 20.1°C (68.2°F) and 13.7°C (56.7°F), respectively. Comparatively cool sea temperature of 19.3°C (66.7°F) might not tempt all tourists for a dip. Weather in January »Weather in February
February in Ha Long sees a slight increase in temperatures from the preceding month. A moderate amount of rainfall is expected, making the region's lush landscapes a sight to behold. The climb in average sea temperature to 19.3°C (66.7°F) entices the adventurous travelers to indulge in seaside activities. Weather in February »Weather in March
March brings with it the spring season, which is often associated with pleasant weather. Rainfall during March is heavier compared to February, totaling 36mm (1.42") throughout the month. Average temperatures continue to escalate slightly, sparking the commencement of the tourist season. Weather in March »Weather in April
April’s weather in Ha Long marks the shift towards steadily warming days. A significant amount of rainfall has been recorded at 53mm (2.09") in April, indicating the progression into the rainy season. The region's natural beauty flourishes, captivating visitors with its verdant landscapes. Weather in April »Weather in May
May in Ha Long embraces the onset of tropical weather. Among the notable changes is an influx of substantial rainfall, with 163mm (6.42") recorded to fall over the course of May. Simultaneously, temperature highs, lows, and sea temperatures ascend, evaporating the increasing supply of rainwater. Weather in May »Weather in June
June announces the arrival of summer in earnest in Ha Long. Last month's rainfall not only retains but also exacerbates up to 224mm (8.82"). Astoundingly, sunlight also beams down for its maximum average duration of 13.4 hours, heating up both the land and sea. Weather in June »Weather in July
The peak of the summer season is marked in July with some of the highest temperatures of the year. The most rainfall of the year also occurs now—255mm (10.04") throughout the month. Residents and tourists anticipate wet conditions coupled with warm temperatures, bringing about a unique environment. Weather in July »Weather in August
August maintains the summer heat while ushering in a slightly different weather pattern. Turning a new leaf, the month records a surprisingly high rainfall of 317mm (12.48"). The balance between high temperatures and heavy rainfall creates a paradoxical yet intriguing climate. Weather in August »Weather in September
September in Ha Long manifests the gradual transition from summer to autumn. Though the rainfall starts to recede to 232mm (9.13"), the level remains significant compared to the rest of the year. The decrease of rainfall does not compromise the charm of Ha Long. Weather in September »Weather in October
October sees a more noticeable transformation into the autumn season in Ha Long. With a substantial decrease in rainfall to 86mm (3.39"), the month enters a less humid phase. While the temperatures remain comfortable, the city enjoys a respite from the heavy rainfall. Weather in October »Weather in November
November brings a blend of autumn and winter mindsets to Ha Long's weather cycle. The city witnesses a significant drop in rainfall, measured at 34mm (1.34") during the month. But overall, November retains a moderate Vietnamese weather charm that appeals to both locals and tourists. Weather in November »Weather in December
December's weather in Ha Long signifies the onset of winter, bringing the year to a cool close. Alongside the festive spirits, expect to find minimum rainfall with only 25mm (0.98") projected for the month. As the temperatures drop significantly, the city's calm winter beauty unfolds. Weather in December »Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature
Ha Long, Vietnam
The warmest month (with the highest average high temperature) is June (34.1°C).
The month with the lowest average high temperature is January (20.1°C).
The month with the highest average low temperature is June (25.4°C).
The coldest month (with the lowest average low temperature) is January (13.7°C).
Average pressure
Ha Long, Vietnam
- Average pressure in January:
1019.1mbar - Average pressure in February:
1016.4mbar - Average pressure in March:
1014mbar - Average pressure in April:
1010.8mbar - Average pressure in May:
1006.9mbar - Average pressure in June:
1003.4mbar
- Average pressure in July:
1003.7mbar - Average pressure in August:
1004.7mbar - Average pressure in September:
1008.9mbar - Average pressure in October:
1014.1mbar - Average pressure in November:
1016.5mbar - Average pressure in December:
1019.2mbar
The month with the highest atmospheric pressure is December (1019.2mbar).
The month with the lowest atmospheric pressure is June (1003.4mbar).
Average wind speed
Ha Long, Vietnam
- Average wind speed in January:
6.3km/h - Average wind speed in February:
7.5km/h - Average wind speed in March:
8.6km/h - Average wind speed in April:
8km/h - Average wind speed in May:
6.7km/h - Average wind speed in June:
5.9km/h
- Average wind speed in July:
5.5km/h - Average wind speed in August:
5.2km/h - Average wind speed in September:
5.2km/h - Average wind speed in October:
5.5km/h - Average wind speed in November:
5.4km/h - Average wind speed in December:
5.3km/h
The windiest month (with the highest average wind speed) is March (8.6km/h).
The calmest months (with the lowest average wind speed) are August and September (5.2km/h).
Average humidity
Ha Long, Vietnam
The months with the highest relative humidity are August and September (83%).
The month with the lowest relative humidity is February (71%).
Average rainfall
Ha Long, Vietnam
- Average rainfall in January:
32mm - Average rainfall in February:
15mm - Average rainfall in March:
36mm - Average rainfall in April:
53mm - Average rainfall in May:
163mm - Average rainfall in June:
224mm
The wettest month (with the highest rainfall) is August (317mm).
The driest month (with the least rainfall) is February (15mm).
Average rainfall days
Ha Long, Vietnam
- Average rainfall days in January:
15.2 days - Average rainfall days in February:
12.8 days - Average rainfall days in March:
19 days - Average rainfall days in April:
20.3 days - Average rainfall days in May:
22.7 days - Average rainfall days in June:
25.3 days
- Average rainfall days in July:
28.3 days - Average rainfall days in August:
26.8 days - Average rainfall days in September:
22.9 days - Average rainfall days in October:
16.7 days - Average rainfall days in November:
14.2 days - Average rainfall days in December:
12.9 days
The month with the highest number of rainy days is July (28.3 days).
The month with the least rainy days is February (12.8 days).
Average sea temperature
Ha Long, Vietnam
The best month for swimming (with the highest average sea temperature) is July (30.8°C).
The coldest months (with the lowest average sea temperature) are January and February (19.3°C).
Average daylight / Average sunshine
Ha Long, Vietnam
- Average daylight in January:
11h and 0min - Average daylight in February:
11h and 30min - Average daylight in March:
12h and 0min - Average daylight in April:
12h and 36min - Average daylight in May:
13h and 6min - Average daylight in June:
13h and 24min
- Average daylight in July:
13h and 18min - Average daylight in August:
12h and 48min - Average daylight in September:
12h and 18min - Average daylight in October:
11h and 42min - Average daylight in November:
11h and 12min - Average daylight in December:
10h and 54min
The month with the longest days is June (Average daylight: 13h and 24min).
The month with the shortest days is December (Average daylight: 10h and 54min).
- Average sunshine in January:
4h and 0min - Average sunshine in February:
5h and 0min - Average sunshine in March:
6h and 30min - Average sunshine in April:
7h and 48min - Average sunshine in May:
8h and 54min - Average sunshine in June:
9h and 54min
- Average sunshine in July:
9h and 0min - Average sunshine in August:
9h and 6min - Average sunshine in September:
8h and 6min - Average sunshine in October:
6h and 42min - Average sunshine in November:
5h and 6min - Average sunshine in December:
4h and 54min
The month with the most sunshine is June (Average sunshine: 9h and 54min).
The month with the least sunshine is January (Average sunshine: 4h and 0min).
Average sunshine days
Ha Long, Vietnam
- Average sunshine days in January:
11.6 days - Average sunshine days in February:
11.3 days - Average sunshine days in March:
8.1 days - Average sunshine days in April:
6.5 days - Average sunshine days in May:
6.8 days - Average sunshine days in June:
3.9 days
- Average sunshine days in July:
2.3 days - Average sunshine days in August:
3 days - Average sunshine days in September:
5.6 days - Average sunshine days in October:
11.8 days - Average sunshine days in November:
13 days - Average sunshine days in December:
15.5 days
The month with the most sunshine days is December (15.5 days).
The month with the least sunshine days is July (2.3 days).
Average UV index
Ha Long, Vietnam
The months with the highest UV index are April, May, June, July and August (UV index 7).
The months with the lowest UV index are January and December (UV index 4).
Average cloud cover
Ha Long, Vietnam
The month with the most cloud cover is January (Cloud cover 65).
The month with the least cloud cover is June (Cloud cover 42).
Average visibility
Ha Long, Vietnam
The months with the highest visibility are January, February, March, April, May, June, October, November and December (9km).
The months with the lowest visibility are July, August and September (8km).





