The other day it was raining and while my car was idling i heard a strange clicking/rattling noise coming from under the hood, it was pouring so i didnt check but i noticed it went off every 5 seconds, i checked next day when it wasnt raining and the noise was gone. Idk if something that wasnt supposed to be getting wet that was getting wet or if i should worry or not..Anybody have any ideas?

 

may be water got on your serpentine belt.you will never know how it did but it could be.mine made some noise too when water got on the belt till l changed my belt. may be you can take a video of it making that noise so that we can help you identify what the problem could be.

 

Did you have the defogger on? (air blowing on the windshield)
If so it was most likely your a/c compressor cycling