Late spring (May to June) and early autumn (September to October) are the most comfortable, with warm days, the sea warm enough to swim and thinner crowds than peak summer. July and August are hot, humid and busy, when Batumi is at its liveliest but also its most crowded and expensive. Batumi is one of the wettest places in Georgia, so rain is possible in any season, and winter is mild but grey and very wet.
Batumi's beach is pebbly and the Black Sea shelves steeply, with currents that can be strong after storms. Swim on stretches where others are in the water, watch any flags, and take care with children; water shoes protect your feet on the stones.
Traffic can be fast and drivers assertive, and some crossings are informal. Cross with care and with locals rather than alone, watch for scooters and quad bikes on the Boulevard, and stay alert around the busy seafront roads at night.
Batumi has a wet subtropical climate and is one of the rainiest cities in Georgia, with heavy downpours possible even in summer. Carry a light rain layer or umbrella, expect high humidity in the hot months, and pack warm, waterproof clothing in winter.