[BNaylor]

Welcome to AF.

Check the cowling seals at the HVAC air intake area passenger side. Also, a cabin air filter helps provides protection against water intrusion.

Based on your symptoms you have the classic signs of an ignition switch going South. You can try the blower motor resistor which is located behind the blower motor against the firewall passenger side but that may not resolve the issue.

Also, just to be sure make sure the battery is good and the alternator is putting out the proper voltage. Check the battery terminals and both positive and negative cable connections.