Similan & Surin Islands (Phang Nga)

February is peak season for the Similan and Surin archipelagos, with glassy seas, bright blue water, and excellent underwater visibility that can exceed 30 meters. Expect minimal rainfall, light winds, and comfortable sea temperatures ideal for full-day snorkeling or multi-dive trips. Both archipelagos sit inside national parks, so daily visitor quotas apply and advance booking with licensed operators is essential. You’ll typically depart by speedboat from Khao Lak, and early departures mean calmer crossings. Beaches here are powdery white, but the real magic lies offshore among bommies, reef walls, and turtle cleaning stations. Facilities are limited, so pack snacks, sun protection, and motion-sickness tablets if you’re sensitive. Note that overnight stays on the islands have been restricted in recent years, making day trips the norm. For the most tranquil surface conditions, aim for midweek dates and morning tours. This is Thailand’s premier February pick for pristine reefs and wow-factor water clarity.