Hanoi weather in general
The southwest monsoon and the South China Sea influence provide Hanoi's humid tropical climate with its characteristic four seasons: spring, summer, fall, and winter. This causes Hanoi to experience hot, rainy summers and super chilly, damp winters. Hanoi's winters and summers are very harsh when compared to those of other Southeast Asian countries so it is necessary to note down when you travel in these seasons.
Hanoi in Spring (February - April)
The months of February and April are typical for Hanoi's springtime. Hanoi experiences moderate to frigid temperatures ( around 14-20 degrees Celcius) in the spring, however the humidity can reach up to 90% (it is super wet everywhere so be careful with your steps). One of Hanoi's defining features is the city's typically modest spring rain. Since this climate pattern encourages plant growth and flowering, spring is the best time to visit Hanoi in full bloom.
Hanoi's celebrations peak in the springtime. Among the various events held in the city, the Tet Festival is the most significant. In Vietnam, families and friends gather towards the end of January or in the middle of February to celebrate Tet Nguyen Dan, more often known as the Tet holiday. The city is experiencing a flurry of popularity, marked by vibrant cultural outbursts.
The locals all dress up for the occasion and the streets are decked and lit up for the occasion. Different resorts and hotels also have their own parties and event. On the other hand, due to the Tet holidays, it is possible that most hotels and transportation options will be fully booked and that some tourist hotspots, such a select number of museums and stores, will be closed. During Tet, when the entire country is in a festive spirit, you can truly appreciate the nuances of Vietnamese culture.
The ideal months to visit Hanoi in spring are March and April, when temperatures average 20-24 degrees. You can enjoy the numerous sights of Hanoi on foot under clear blue sky and comfortable temperatures. In addition to satiating your hunger with some of Hanoi's most delicious specialties like various kinds of Vietnamese Noodles, Banh Mi, rice, you should use this time to check out popular tourist sites in this ancient city like Hoan Kiem Lake, One Pillar Pagoda or Westlake.
Hanoi in Summer (May-August)
In contrast to the mild temperatures of spring, summer brings scorching heat and unexpected downpours in the late afternoon. The global warming problem makes the summers in Hanoi particularly harsh, with average temperatures of 30 degrees. And particularly, these days in Hanoi, it could reach more than 40 degrees Celsius.
Summers in Hanoi are known for their heavy rain, therefore visitors are advised to pack an umbrella or raincoat before venturing out. Some areas of the city may be flooded for many hours during the summer due to the large quantity of rainfall, making traffic difficult. However, summer months are still among the best months to visit Hanoi and sample the country's wide variety of exotic tropical fruits, including the dragon fruit, jackfruit, lychee, and many more.
The temperature in May is mild compared to the rest of the summer. In May, you can expect temperatures of about 28 degrees Celsius and mostly cloudless sky. However, June ushers in full summer with temperatures between 29 and 33 degrees Celsius. Summertime highs might also reach 40 degrees. The highest temperatures and first significant rains often occur in June. The heaviest rain falls in July and August, and it can reach 200 millimeters or more. The humidity, however, is much above 75% all through the summer. Because of the high heat and frequent rainfall, summer is generally not a popular time to visit Hanoi. However, this means that rates are lower, lodging is more accessible and inexpensive, and bookings can be made with more ease.
Hanoi in Autumn (September - October)
September and October make up the relatively brief autumn season. Very little precipitation falls during this season, and the temperature is often mild and pleasant, with just a slight increase in humidity. If you plan to travel to Hanoi in autumn, you will fall in love immediately with this city, no kidding! With an average temperature of 25 degrees, pleasant sunlight, and chilly wind, autumn is the most lovely season in Hanoi.
It's the perfect time to go sightseeing in Hanoi and the neighboring areas. Actually, you will settle for almost anything. Visit one of the area's numerous thriving retail centers or fine dining restaurants for some treats. To learn about the city's history, you should take a stroll through the congested streets of Old Quarter, where hawkers abound. Or you can take a tour to the Vietnam Museum of Ethnology, Ho Chi Minh Mausoleum, West Lake, Hoa Lo Prison Memorial, Temple of Jade Mountain, and Dong Xuan Market - these are a few of the sights that you may get interested in.
If you crave food, you might wander from market to stall eating great street cuisine. It's nice enough outside to go window shopping and eat street cuisine without worrying too much about the heat, humidity, rain, or cold. In addition, fall is full of exciting celebrations and festivities. In autumn, you must try Cốm - young rice with a light green color that you will find on street vendors. The slight fragrance of lotus leaf wrapping Cốm is truly the taste of Hanoi autumn that I cannot resist telling you!
Hanoi in Winter (November - January)
Hanoi experiences all four seasons, and winter lasts for a few months from the end of the year until the beginning of next year. Temperatures are often low, averaging just around 11 degrees Celsius. Cold and wet weather is typical throughout the winter months. As a result of the monsoon, December and January in Hanoi may be bitterly cold, with thick fog producing a surreal scene. Winds and excessive humidity compound the chill of the low temperatures, making it feel much less bearable than it actually is.