Know your surrounding area-Don't rely on radar
Don't rely on your radar in a storm/squall. Often the radar will pick up "returns" and the storm will look like a large island. This scared the heck out of me the first time it happened. It blanked out my forward route, and blocked the returns of the small islands around me. Fortunately, I knew the area and where to run, but felt really uncomfortable until I got a proper return and visuals again.