Does cold weather affect silicone mousepads?

Yes, cold makes silicone mousepads stiff and slippery. Below about 60°F (15°C), the silicone hardens like a stale gummy bear, losing its tack so the pad slides and your mouse doesn’t track smoothly. Warm it with your hand or a low desk lamp to fix it, or switch to a cloth pad that doesn’t care about cold.