This has certainly been a hot summer so far. During the hot summer months we tend to tax our electrical systems the most. With AC's running 24/7 and pool pumps and heaters going it is about the most electric you'll use all year. If you are going to have an electrical problem now is the time it will surface.
One of the most common problems we see is water damage in the main breaker panel. Water can find its way into the electrical panel a few different ways. The most common route for the water is rain getting inside the SEU or service entrance cable. That is the big cable you see on the side of the house, which enters the top of the Meter pan. Very often you can see the insulation on the outside has started to shred and become porous. The water will seep down through the cable and the meter all the way to the main panel. It isn't something that happens overnight, but rather happens over years. Generally any service will have some water damage after 15 to 20 years.
Water can also enter through openings that are not sealed properly where the wire or pipe enters the house. This can be easily fixed with some silicone caulking. However the water is getting in, it is not something to leave unattended. Eventually the connections in the panel will become corroded and cause a bad electrical connection. This causes heat and could lead to circuit breaker failures or worse.
If you suspect you are getting water in your panel call a licensed electrician to take a look. By observing the outside cover you can usually tell you have a problem by evidence of rust around the breakers or at the bottom of the panel.
August is coming, so we have another month or so of hot weather. Stay cool and be safe!