I have no snow tires or no traction control. I used my Boxster in extremely hard rain (we get tons of rain in small amounts of time here) and she handled like a dream. If you are feeling insecure you can always put the spoiler up to keep more traction on the rear wheels.
It's actually kind of fun to drive the Box in the rain, you can do hard starts and get a small slide without getting into too much trouble
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