Ha Tinh's Climate
Wedged between the Truong Son range to the west and the sea to the east, with the Hoanh Son spur and Ngang Pass walling off its southern end, Ha Tinh takes the full force of north-central Vietnam's weather: a scorching foehn-wind summer, torrential autumn rains and a long, damp winter. Around 3,034 mm of rain falls in an average year — among the highest totals in Vietnam — and the wet season stretches from roughly April all the way into January.
The furnace months
From May to August the southwest "Lao wind" spills over the Truong Son mountains and arrives hot and bone-dry. June is the peak, with average highs of 34.9°C, and on strong foehn days Huong Son, Duc Tho and Ky Anh can hit 38–40°C. Rice and peanut fields along the La River dry out fast, which makes the Ke Go reservoir vital for irrigating Cam Xuyen and Thach Ha. The upside: this is prime beach season at Thien Cam, Xuan Thanh and Xuan Hai, with calm seas and dependable sunshine — just stay out of the midday sun.
October, the flood peak
Ha Tinh is one of Vietnam's great rainfall centres. In late autumn, cold surges from the north collide with typhoons and the tropical convergence zone, and the Hoanh Son wall wrings the moisture out over this narrow strip of land. October alone averages about 915 mm of rain across roughly 23 rainy days — it rains nearly every day. Water races down the Ngan Sau and Ngan Pho rivers into the La, flooding Huong Khe, Vu Quang and Duc Tho, while low-lying Cam Xuyen can go under whenever Ke Go has to release water. September–November is also typhoon season; fishermen at Cua Sot and Cua Nhuong haul their boats ashore well before a storm arrives.
Drizzly winter, clammy spring
The northeast monsoon brings a real chill from December; January is the coldest month, with average lows of 15.7°C, and cold snaps can dip below 10°C in the Huong Khe and Vu Quang uplands, often with thick fog on the Ho Chi Minh Road. Grey drizzle can drag on for a week at a time, followed in February–March by the clammy "nom" humidity that leaves floors sweating. It is transplanting season on the Can Loc and Duc Tho paddies, and flowering time for Huong Khe's prized Phuc Trach pomelo — a long cold spell can hurt the fruit set.
When to go and what to pack
Beach trips to Thien Cam and Xuan Thanh are best from April to early August; bring serious sun protection. February–April suits climbing Hong Linh mountain and visiting Huong Tich pagoda. Skip the Huong Khe and Vu Quang back roads in September–November, follow typhoon bulletins closely and expect flooded causeways. In winter, pack a warm layer and keep a light raincoat handy — the drizzle rarely lets up for long.