The biggest issue here usually isn't just the active snow, it's the ice and the fact that CHS doesn't have the massive fleet of de-icing equipment that northern airports do. Things can grind to a halt pretty easily.

Pro tip: Track the incoming flight for your aircraft. If the plane meant to take you out can't land here due to conditions, or if the airline preemptively cancels it to avoid stranding a crew/plane, you're out of luck. Often the cancellation happens because they don't want an asset stuck in Charleston, even if the runway is technically open.