I'd be tempted to get a mist system to assist the air conditioners. There are some that do 1/2 gallon per hour per nozzle.
The only place in my RV world where I tripped a breaker, inside my rv, was on Mesa AZ on July 29.
If you have a way to monitor voltage--set the fridge to propane--and try running just one air conditioner on the 15 amp shore power. If the voltage stays at 108 or above--then you are fine. Do check voltage often.
Do you have a tarp you could place over the front windshield? If not, pick one up at a dollar store.