There is no single high season. July and August are the busiest months and the driest, but they are not the best for grizzlies, storms or salmon, and they are the months the ferries and Tofino fill up. Decide what you came for first and read the row for it.
Spring, March to May
The grey whales come past Tofino, the Butchart Gardens are at their most photographed, and prices are not yet at their summer level. Victoria is mild and often dry by May. The west coast is still wet, and some Tofino operators only start their full schedule in May. Highway 4 can still see snow at Sutton Pass in March.
Summer, June to September
Everything is open and everything is busy. June and early September have most of the advantages, long days, calm water, the full tour schedule, with fewer people on the ferries. Reserve vehicles on the ferries, book Tofino and Telegraph Cove accommodation months ahead, and expect Victoria's Inner Harbour to be crowded on cruise-ship afternoons. Wildfire smoke can affect visibility in late summer in some years.
Autumn, September to November
The best window for wildlife: grizzlies on the salmon rivers into October, humpbacks still in the strait, and the chum run at Goldstream Provincial Park, twenty minutes from Victoria, drawing bald eagles from late October. The Cowichan Valley is in harvest. Rain returns to the west coast by October and the storm season begins to build.
Winter, December to February
Winter is not the dead season here. Tofino and Ucluelet sell it as storm-watching season and the coast is at its most dramatic; the surf is at its biggest; Victoria is the mildest city in Canada and rarely sees snow settle; the Butchart Gardens run their winter lights in December. What closes is the north: most Telegraph Cove operators shut, and Highway 4 and Highway 19 north of Campbell River carry winter tire rules. Whale watching continues from Victoria on a reduced schedule.