The best time to visit Kas is from May to October, and September is the best single month. July to September gets almost no rain at all, and the sea peaks at about twenty-eight degrees in August.
December to February is the window to avoid. December is the wettest month of the year, the sea falls to about sixteen degrees, and most dive centres and pensions are closed.
| Month | High/Low (°C) | Rain |
|---|---|---|
| January | 16°/ 10° | 7 days |
| February | 16°/ 10° | 10 days |
| March | 19°/ 11° | 5 days |
| April | 21°/ 14° | 5 days |
| May | 27°/ 18° | 1 days |
| June | 30°/ 22° | 2 days |
| July | 32°/ 24° | 1 days |
| August | 33°/ 25° | 0 days |
| September | 31°/ 23° | 2 days |
| October | 28°/ 21° | 3 days |
| November | 24°/ 17° | 6 days |
| December | 18°/ 12° | 10 days |
May is the shoulder month, dry and about twenty-five degrees, though the sea is only twenty and still cool for repeated swimming.
June is where it comes together. The air reaches thirty and the sea twenty-four, making it the first month that works for both walking and water.
July and August are the driest months of the year, with barely any rain between them, and August is the warmest the sea gets at twenty-eight degrees.
Kas is the mildest of the Turkish coast resorts in summer. August averages about thirty-three degrees here against thirty-five in Fethiye and Marmaris, thanks to its exposed peninsula position.
September is the best month of the year. The air is at thirty and the sea still at twenty-seven, with almost no rain.
October is the last good month. The sea holds at about twenty-four but the rain starts returning, so early October is much stronger than late.
November is the turn of the season. Rain builds and the sea drops to about twenty-one degrees, which ends comfortable swimming.
Dive boats and pensions start closing. Kas is a small town rather than a resort strip, so out of season means properly quiet.
December is the wettest month of the year, with January close behind. October to January together carry the great bulk of the annual rainfall.
The sea bottoms out near sixteen degrees in February, which is thick-wetsuit territory. Most dive centres and pensions are shut.
March and April are dry and mild on land, in the high teens to low twenties, and good for the Lycian Way and the ruins.
The water is the catch. April's sea is still about seventeen degrees, so this is a walking season rather than a swimming one.
Kas has more than fifteen dive centres and around fifty dive sites, including six artificial reefs, a Second World War aircraft wreck, a nineteen-fifties cargo ship, and the Archaeopark with its reconstruction of the Uluburun wreck.
Sea temperature is the honest guide to when to dive. February's sixteen degrees needs a thick suit, while June to October runs twenty-four and above. At nearby Kekova the water is clear enough to pick out the staircases and columns of the sunken city from the boat.