You will extend you sailing season for years to come, and add safety when sailing in cold water in the spring.
I had a beach cat years ago; when other beach cat sailors told me they wanted more wind, I told them to buy a dry suit. t blows harder in the winter. Sailing can actually be pleasant down to about 32F; below that, if there is any spray, it gets a bit grim on the face. Ski goggles help a lot, as do good Gore-tex ski gloves.
I posted a piece about winter sailing:
Sail Delmarva: Search results for winter sailing bubbler