When it rains my overdrive and cruise control stops working

I would look for a bad connection at the transmission. If the seal is missing at any one or more of the wires, it could be letting water in the connection and causing funkey things to happen. If you find corosion, clean it with contact cleaner and a little brush. Squirt a little RTV sealant on the wire side of the connector, making sure to get it sealed well and let that cure over night. Next day squirt some silicone sparkplug boot grease on the female side of the plug (in the holes) and plug it back together nice and tight.
If that don't solve the problem, keep checking for loose or bad connectors in all of the systems that could effect that. Also check to make sure you don't have a leak into the interior that could be getting to your transmission control module.