Isla de la Plata in March

June through November is peak season for good reason. Humpback whales arrive in June and stick around through September, putting on daily shows of breaching and tail slapping. The weather stays dry with calm seas perfect for boat trips. But here's the insider tip: October and November offer the best of both worlds. Whales are still around in early October, but crowds thin out after September. Sea conditions remain excellent, and you'll pay 20% less for tours. December through May brings rain and rougher seas that can cancel boat trips. If you come during rainy season, build in extra days since weather delays are common.