Orkney's weather is famously changeable, but the islands are less harsh than their latitude suggests, thanks to the warming influence of the Atlantic. Summer temperatures sit around 15°C and winters are mild by Scottish standards — the sheltering water keeps frost uncommon. Wind, however, is a constant. Come prepared for it at any time of year.
June and July are the prime months: long days (midsummer brings near-total daylight), all visitor sites open, and the best odds of fair weather. The summer solstice is celebrated with events at the Neolithic sites. The St Magnus International Festival takes place each June, filling Kirkwall with classical music, theatre, and literary events.
August and September are also excellent — crowds thin out slightly and the light has a quality that photographers prize. Winter offers something else entirely: the Aurora Borealis is visible on clear nights, the Norse atmosphere of the islands is at its most pronounced, and accommodation prices drop sharply. The islands celebrate Christmas and New Year with gusto.
The Ba' — Kirkwall's ancient, lawless street football match played on Christmas Day and New Year's Day — is one of the more extraordinary spectacles you will see anywhere in Scotland. There are no rules, no referee, and potentially hundreds of players; it typically lasts several hours.