The best time to visit Izmir is April to June and September to October, and May and October are the two best months. This is a city and ruins destination, so walkability rather than sea temperature is what should decide your dates.
July and August are too hot for Ephesus. They average around thirty-four degrees with records to forty-three, on unshaded marble and open ground, while December is the wettest month of the year.
| Month | High/Low (°C) | Rain |
|---|---|---|
| January | 13°/ 3° | 5 days |
| February | 15°/ 5° | 7 days |
| March | 19°/ 8° | 5 days |
| April | 22°/ 9° | 6 days |
| May | 27°/ 14° | 1 days |
| June | 33°/ 19° | 3 days |
| July | 35°/ 20° | 1 days |
| August | 37°/ 21° | 0 days |
| September | 32°/ 17° | 3 days |
| October | 28°/ 15° | 2 days |
| November | 23°/ 13° | 7 days |
| December | 15°/ 7° | 7 days |
May and October are the two best months in Izmir. Both sit in the mid twenties, dry enough for a full day outside and comfortable for Ephesus.
October has the warmer sea, at about twenty-one degrees, while May's reaches only nineteen and a half. Neither is a swimming month by Mediterranean standards.
March is still cool and April warms into the low twenties, with the rain falling away steadily. Early June reaches thirty-one and is the edge of the good window.
Mid-June is the strongest reason to book this page. The Izmir International Festival runs from mid-June to mid-July, with performances staged in the ancient theatres at Ephesus and Metropolis, which is worth accepting a hot day for.
September eases to about twenty-nine degrees and the sea is at its warmest for the year, close to twenty-four.
The Izmir International Fair fills Kulturpark in the first days of September, in the inner-city park, landing right at the start of the shoulder season.
July and August average around thirty-four degrees and the records run to forty-three. Ephesus is unshaded marble and open ground with almost no cover.
That makes the heat a trip-ruiner rather than a discomfort. If July or August is fixed, go at opening time and be finished by mid-morning.
December is the wettest month of the year with January close behind, and November is already properly wet.
The city still works, though. Kemeralti, the bazaar, the seafront cafes and the museums are covered or indoors, so Izmir handles rain far better than the beach resorts down the coast.
January is the coldest month, averaging nine degrees across the day, and February has the coldest sea on the Turkish coast at under fifteen degrees.
Izmir is not a mild-winter coastal city. The record low is below minus eight and even April has dipped near zero, which makes it a different proposition from Fethiye further south.
Izmir's sea is nearly three degrees colder in August than Fethiye's, and in February it is the coldest on the Turkish coast. Aegean-north water is not Mediterranean-south water.
So book the right trip. Izmir is about the city, the food and Ephesus, with the coast as a bonus rather than the point. For swimming, Kas or Marmaris further south are the better choices.