Effects of Heat and Humidity

Is there any documented information on the effects of heat and humidity on computer hardware such as network cards, patch cables, ports, etc. We are in the midst of a heat wave here in the Midwest and every day we have thunderstorms, lightening and lots of heat and humidity. My network connections are failing and then miraculously “heal” themselves after I shut the server down numerous times. We have had other instances of unexplained failures followed by unexplained recoveries. Any ideas?