October, November and April are useful starting points for a Hai Phong sightseeing trip: they generally offer a more comfortable balance of warmth and rainfall than midsummer. If swimming at Do Son or Cat Ba is your priority, the warmer months give you more options, but you need flexibility for heavy rain, thunderstorms and sea conditions.
Hai Phong has a cool winter as well as a hot, humid summer. Pack for the season, and check the forecast for your actual destination: weather in the city does not tell you whether a ferry crossing or a Lan Ha Bay cruise can operate.
Choose a season around your plans
- City walks and cultural sightseeing: consider October–November or April. Keep rain protection with you, and allow for cooler mornings in late autumn.
- Beaches and swimming: late spring through early autumn offers warmer conditions. Pick the beach day from the short-range forecast and follow local swimming restrictions.
- Hiking and cycling: prioritize a dry forecast and manageable heat. A cooler month is not automatically suitable if trails or limestone steps are wet.
- Winter sightseeing: December–February can suit travelers who prefer cooler weather and do not require beach time. Bring warm layers for evenings and exposed boat decks.
Hai Phong weather month by month
The temperatures below are rounded monthly averages from the mainland Phu Lien station for 1991–2020. They combine daytime and nighttime conditions; they are not daily highs, lows or a forecast. Individual hot days, cold spells and conditions on Cat Ba can differ substantially.
January: cool weather and warm layers
The monthly average is about 17°C. January is relatively dry compared with summer, but rain and cold spells still occur. A jacket, long trousers and closed shoes are more useful than packing only beach clothes, particularly if your plans include a windy waterfront or boat trip.
February: chilly mornings and possible drizzle
Expect a monthly average near 18°C, with damp, gray periods possible. Keep a warm layer and light waterproof jacket available. If your trip overlaps Tet, check the holiday dates separately: transport demand and restaurant opening arrangements can matter as much as the weather.
March: milder days, lingering damp weather
The average rises to about 20°C. Drizzle, humidity, fog and another cold spell can still interrupt a pleasant spring day, so do not leave all your warm clothing behind. For Cat Ba viewpoints or bay photography, make the final plan close to the day when visibility is clearer.
April: warmer sightseeing weather
At an average of about 24°C, April is a practical month for combining city visits with time outdoors. Warm sunshine is possible, but showers and thunderstorms also need a place in your planning. Book island transport and accommodation early if you are traveling around the April 30–May 1 holiday.
May: heat and a wetter pattern
The monthly average reaches about 27°C, and rainfall increases. Start longer walks early, carry drinking water and leave time for a shaded or indoor break. Do Son and Cat Ba become more appealing for a beach-focused trip, provided local conditions are suitable for swimming.
June: hot, humid days
June averages about 29°C and is among the hottest months. Afternoon temperatures can be higher than that average, and humidity makes a long exposed walk demanding. Allow for showers and storms rather than assuming a sea breeze will keep every activity comfortable.
July: summer travel with room to change plans
The average remains near 29°C. This is a hot, rainy month when tropical weather systems can affect coastal trips. Keep a spare day if a boat excursion is central to your visit, and avoid scheduling an essential flight immediately after your return from Cat Ba.
August: the wettest month in the long-term pattern
August averages about 28°C and has the highest average monthly rainfall of the year. That does not mean continuous rain every day, but heavy downpours can disrupt outdoor plans. Choose footwear with grip and keep your phone and travel documents in a waterproof pouch.
September: still warm, with substantial rain risk
The average is about 27°C. September should not be treated as the end of hot weather or storm risk; it remains one of the wetter months. If you plan to attend a local festival, check that year’s program and lunar-calendar dates instead of assuming the event always falls in September.
October: less rain, but no weather guarantee
October averages about 25°C, with substantially less rainfall than late summer in the long-term pattern. It is a sensible month to consider for city sightseeing, walking and island trips. Continue checking warnings: a lower monthly rainfall average does not rule out a storm or a very wet day.
November: comfortable walking weather, cooler evenings
The monthly average falls to about 22°C. November can work well for a trip focused on food, architecture and cultural sites, with a light jacket useful after sunset. Beach comfort depends on the actual weather and your tolerance for cooler conditions.
December: winter arrives
The average is around 19°C, although a cold spell can feel much colder. December has low rainfall in the long-term record, but dry conditions do not guarantee warmth or calm seas. Pack layers and ask about room heating if you are sensitive to cold.
Rainfall, storms and Cat Ba boat connections
Hai Phong’s wetter season broadly runs from May to October, with much of the rain concentrated in summer and early autumn. Tropical storms are a particular consideration for summer and early-autumn travel, while strong northeast winds can also affect the sea in the cooler months.
For Cat Ba, Lan Ha Bay or another coastal boat trip, check the marine forecast and the operator’s departure notice as well as the city forecast. A rain symbol alone cannot tell you whether a sailing will run. Wind, waves, visibility and restrictions issued by the authorities all matter.
- Before booking: read the specific cancellation and rescheduling terms. A weather disruption does not create one universal refund policy for every hotel, transfer and cruise.
- Before traveling to a pier: confirm that your departure is operating and ask when the next status update is expected.
- If services are suspended: follow the official instructions. Do not assume a private boat or a different operator can bypass a closure.
- For an onward flight or train: consider returning to the mainland the previous day. Extra time helps with ordinary delays, but cannot guarantee a crossing during a prolonged closure.
Build a practical sightseeing day
In hot weather, put the longest outdoor section early in the day and allow a proper lunch break. In light rain, shorten walks and use sheltered meal or coffee stops. During severe-weather warnings, staying at your accommodation may be more appropriate than replacing a canceled cruise with another exposed coastal activity.
If you want a guided half-day visit to Do Son’s cultural sites, the Hai Phong City Tour has morning and afternoon departures from Hai Phong hotels. Its itinerary includes Ba De Temple, Bao Dai Villa, K15 Pier and Tuong Long Tower, followed by a mall stop. Much of the route is outdoors or near the coast, so choose it for suitable sightseeing weather and confirm the day’s arrangements.
What to pack and check before leaving
- For the cooler months: layers, a wind-resistant jacket, long trousers and closed shoes.
- For warmer months: breathable clothing, sun protection, drinking water and a spare shirt for humid days.
- For rain: a lightweight rain jacket, shoes with grip and protection for electronics and documents.
- For boats and beaches: a layer for wind, plus swimwear only if your plans and local conditions allow swimming.
Use Vietnam’s National Center for Hydro-Meteorological Forecasting for weather and marine warnings, and check your transport provider’s messages close to departure. Choose the month for the kind of trip you want; use the short-range forecast to decide the order of your activities.