AC works till ambient temp gets around 88-90 degrees then just blows regular air

Hello, your vehicle doesn't know to act differently when temperature start getting higher. Either your air conditioning is not really working even when less than 88 degrees, or there is a random electrical failure of your air conditioning system during certain occasions. Either there is a refrigerant system issue, or you've got an electrical issue under the hood with the coil, clutch or cycle switch. Or, you could have a blend door issue inside the vehicle. Testing needs to be performed to drill down to one area.