A dehumidifier would solve the problem of humidity fluctuations and then you have an alternative water source even though your well water should work just fine. High temps can make keeping smartpots moist a challenge and makes for fluffy buds and weakass smoke. Temps you list are not too bad but you don't want to be much above 85 deg F for too long. Fans can only do so much to control heat but it will be easier to keep your temps in a safe zone when you've got a proper grow tent and inline filtered exhaust fan(s).