Question for the experts: Is this battery behavior normal under heat?

Hi Folks,
I had my Clarity sit for 2 weeks sitting in my garage (temps around 90F inside) while I was away on vacation. When first driving it upon returning I immediately noticed the EV range decreasing fast, from the 60+ miles I used to get before leaving to around 42. It was HOT at 113F and I also had to leave the car out for a couple of days because my son was doing some mechanics inside the garage. This is my second summer here but I didn't notice such big change last year even with 115F. But what freaked me out is that when plugging it to charge a low continuous beep started coming from behind the car. next drive was the same thing, with barely reaching 40 miles on the full charge. For next charge I waited until 10PM for the heat to subside but got the same beep. In neither case I heard the ventilator working. Next drive (earlier in the morning and 95-98F) still got barely to 45. I waited until today at 6AM (when I got the lowest temp at 92) to charge and got no beep, but I could hear the ventilator working. In no case I got any sort of warning messages. Could it be that the heat may have somehow damaged the battery or may it just be temporary high-temperature related efficiency decrease? Or may it be the continuous use of A/C? However, last year under the same conditions I didn't notice any significant decrease.

 

After two days below 110, the range went a bit up and has stayed around 50, and the continuous beep is no more. Will get myself one of those OBDII readers to keep track of capacity.