Autumn is the open secret of this coast, and the arithmetic behind it is simple: sea temperature lags air temperature by about two months.
The warmest water of the year
Which arrives in late August and September, not July. The beaches are nearly empty by then and the parking problem solves itself. See beaches and check what is still lifeguarded before swimming.
The light
The harbour faces broadly west, and autumn evenings down it are the best photography on this coast. Baiter, Hamworthy and Upton Country Park all look into it.
The birds
The first overwintering waders arrive on the mudflats, and ospreys pass through on migration. See wildlife.
The prices
Accommodation drops sharply after the schools go back, and tables that needed booking in August are walk-in by October. See accommodation.
What to know
Some boat services and beach cafes reduce hours from October. Check before relying on one.
See Poole in autumn and the autumn top 10.