I went for my 60th birthday weekend in early March last year and it was glorious - clear blue skies and around 21C. I'd thoroughly recommend a visit - the place is absolutely fascinating and the retail therapy first class!! We flew with Turkish Airlines for £110 return each - the service, meals onboard were exceptionally good and light years ahead of BA. Stayed at a fantastic boutique hotel virtually across the street from the Grand Bazaar and 5 mins from Sultanahmet (Blue Mosque, Hagia Sofia etc) called 'Hotel Niles' for about £45 per night for the room including a fab buffet breakfast. Only 4 rooms were being used as it was out of season so we got an automatic upgrade to a suite. I'd go back like a shot!
I was there this March gone and I got sunshine everyday around 17°C to 20°C but once it's dark it gets a bit cooler. So you need a jacket I'd say!
The same as here... Snow, rain & sun all at once! (y) You'd need to wrap up.
same request :)