Check Your Fluids
High temperatures can cause fluids to break down faster. Check all fluid levels, including engine oil, coolant, transmission fluid, brake fluid, and power steering fluid. Top off any low fluids and change them as needed, especially if you're due for scheduled maintenance.
Test Your Air Conditioning
There's nothing worse than getting stuck in traffic on a sweltering day with a broken A/C. Test your air conditioning before the hot weather hits to make sure it's blowing cold. If it's not working properly, have it inspected by a professional.
Inspect Belts and Hoses
Heat can cause belts and hoses to crack, blister, or wear out prematurely. Take a look under the hood and check for any signs of wear. If anything looks questionable, have it replaced.
Check Your Battery
High temperatures can shorten the life of your battery. If your battery is more than a few years old, consider getting it tested to see how much life it has left. Weak or dying batteries often fail in hot weather.