2001 Solara Conv. White Smoke on start up

I just bought a Solara which runs great and quite as can be. No loss of coolant or oil, but the day after purchase(cash) billowing white smoke on start up only in warm weather. Stop in 30 seconds and does not return while driving/idling. It does Not happen every day, but 3 days a week. Just bought the car and prior owner said she took to dealer and another mechanic and both said no leaks detected and nothing one computer and didn't know why the white smoke. Prior owner said doesn't do it in Fall or Winter, only late Spring and Summer and intermittent even then, here in Florida. Any suggestions would be appreciated.

You probably have a small head gasket leak allowing coolant to drip into one of the cylinders as it sits. A leak-down test should be able to confirm this.