In Istanbul the weather, the crowds and the price are never good at once. Which one you are willing to give up decides the month.
April to June. The most balanced stretch. Fifteen to twenty-five degrees, the rain easing, evenings warm enough to sit outside. April is tulip season and the city is in flower. In exchange, crowds and prices are high; late May and early June are the busiest days of all.
July and August. Hot and humid; the middle of the day is hard going on foot. In return the evenings are long, the ferries run late and the waterside is cool. The flats have air conditioning, but move your walking to the morning and the late afternoon.
September to November. If you ask us, the best time of year. September is still summer, October is mild and clear, November is wet but empty. The light is at its best in these months; if you are photographing, come in October.
December to March. Cold, windy, with occasional snow. The city is quiet, there are no museum queues and prices are at their lowest. We recommend it to anyone who wants Galata with empty streets — but bring waterproof shoes, because the hills are slippery when wet.
The crowd calendar. The city empties at Ramazan Bayramı and Kurban Bayramı, but hotels and flights fill up; check the dates in advance. New Year week is expensive.
Our own advice: the first half of October. Good weather, the sea still blue, the crowds dispersed and prices down from summer.