San Fran Planning... any input?

cocojack10

Dh and I would like to take a solo trip before beginning to think about TTC #3.  We are thinking about SF, but aren't 100% committed to it.  Ideally, I'd like to go in end of Mar or April.  Anyone been in that period?  We for sure want to do the wine country... too cold?  Are the wineries open?  Any input would be greatly appreciated!  We'd prob go for 4-5 days.