Many possible conditions. Is there a GFI outlet in the bathroom? Could be that the bathroom light and your system outlets are on the load side of the GFI outlet (which would trip in many wiring situations with switched devices downstream). Or, could be that the bathroom light switch is wired to the neutral instead of the hot and your equipment is on the same circuit.
Also, check your outlets with a plug-in type three light tester. You may have a reversed hot-neutral. As far as the bad weather problem, check to see that your main panel is grounded properly to the water pipe or grounding rod. Could be a loose or corroded connection.
I would first find another circuit or install a dedicated circuit and take it from there.
Also, check your outlets with a plug-in type three light tester. You may have a reversed hot-neutral. As far as the bad weather problem, check to see that your main panel is grounded properly to the water pipe or grounding rod. Could be a loose or corroded connection.
I would first find another circuit or install a dedicated circuit and take it from there.