I have observed that the Stipers can be caught on flies 12 months of the year in Nor Cal.

I would say the only months that are really tough seem to be December, January and February when the water is sub-50 degrees.

During these months some of the hardcore Stripers people do catch fish on flies but they have to work at it.

March through November seems to be the time that most anyone can get lucky and catch some on a fly with water temps at 50 degrees and higher.