Tomatoes will not set fruit in temperatures higher than 85F, some 90F degrees. Pollen becomes unviable. If it's super humid, pollen because too dense, heavy, to do much good. Keep the plants healthy by side dressing them with fertilizer. You can also try shading them with your awesome bed sheets, and have a light mister going during peak heat hours. They will fruit once the temperatures come back down. And when Fall sets in, don't forget that you can make all kinds of yummy dishes with unripened tomatoes.
The heat, as you know, kills the cool weather plants, but it also has detrimental effects on your cowpeas, common beans, corn and sorghum. ( cotton, rice and wheat as well, FYI). If your overnight temps are reaching above 75F, good luck getting any of the above to do much of anything.
If you are entering drought, or in a constant one, flooding the garden a few times a week, in the evening, will help the chances of your plants producing for you. Do not flood them every night, 3x a week, or when the soil at root level starts to dry, is all you need. Be sure to side dress with fertilizers! When watering, you need to remember that evaporation is a huge factor. You are losing more moisture than you think.
Do not flood your orchards, it causes the soil to lose the oxygen for the roots to survive. A good soaking is fine.
Well, that's what I would do if I had a garden.