I would guess that they are drying out. Can you bring them indoors and put them next to a window sill? Also If you can cover them with some plastic that will help increase the humidity.

Well, I water them by hand every day with hose spray nozzle. If they ever go completely dry after they have started to germinate, does this kill the seeds?

If they dry out it can kill the seeding. Plus that kind of heat is a bit high for seed starting. The best way to start seeds is to use damp seed starting mix (damp like a wet sponge). 75ðF is a good temp. You can start them indoors then move them outside once they are a bit larger.

I would start them inside in a plastic bag in a moist paper towel. That is how I start my tomatoes and sweet peppers. I start them on top of my tropical fish aquarium. If I did not have that, I would test the temperature on top of my DVR, amplifier, computer, or other electrical or electronic appliance.

Start checking them for germination every day from the earliest anticipated sprouting time on the seed package. Transfer them to a lighted tray of planting mix when they germinate. You might be able to transplant directly from the starter tray, or may have to transfer to an intermediate pot. You will have to decide.

I know that is not practical for many vegetables like root or bulb or leaf crops, but is practical for the crops you mentioned.

How old are the seeds and how have they been stored? If they were in a hot and humid environment, they may not be good anymore.

Are you planting them at the right depth for the seed?
Can mice get to the seeds in the carport?
Are the pots of seeds kept continually moist till plants appear?