Calbayog has a tropical climate with no real dry season. Rain falls throughout the year, but the wettest months run from October through January when typhoons regularly track across the Visayas — Samar sits in the most exposed corner of the country for these storms, and serious tropical weather can shut down roads and ferries for days. The driest stretch, typically March through May, is also the hottest.
The best time to visit is from February to early June. Beach trips and cave hikes are most rewarding when the rivers are low and the dirt roads are passable. Time a stop around the first week of September if you can — the Sarakiki-Hadang Festival fills the city with parades and rooster-costumed dancers around the feast day of Our Lady of the Nativity. Avoid the late-year typhoon season unless you have flexible plans.