Spring (March–May) is the best time for birding — migratory songbirds and shorebirds pour through on the Central Flyway, and the weather is warm without being oppressive. April and May are peak migration months and the birding can be spectacular after a cold front grounds a major push of migrants.
Summer (June–August) is peak beach season: water temperatures are in the 80s, the fishing is excellent, and the town fills with Texan families on vacation. It is also hurricane season; check conditions if you are planning a trip in August or September. Autumn (September–October) brings a second migration wave and fewer crowds.
Winter is mild and quiet. The beach is walkable and the birding is good — wintering shorebirds, ducks, and the occasional rarity make Port Aransas worth visiting year-round for birdwatchers.