I live and frequently fly in Gilbert. Yesterday the M2P battery was warmer than it usually is, but no warnings from my bird/controller and flew 2 batteries from full to about 30% with apparently normal flight times.
Not sure I can answer your question directly, but I’ll be watching closely as our temps rise into triple digits. I usually fly within a couple of hours of sundown, but may have to change to early morning to get ambient temps in the 80’s.
"The batteries should be used at temperatures between -10° and 40°C. Use of batteries in environments above 50°C can lead to fire or explosion. Using batteries below -10°C will severely reduce performance, as they will not meet normal use requirements. Allow the batteries to return to a normal operating temperature before use."
As Mossiback states.. The manual gives an operating temperature range of 14 degrees to 104 degrees F. I'm not comfortable flying when it's over 90.. The craft may work, but it is more stressful to the battery.
Another point to remember is not to store your batteries in a hot location ie your parked car.....hope that isn't too obvious.
The temp of the batteries is the air temp plus heating due to being in direct sunlight (the road surface can be hotter than the air temp because it absorbs the sunlight and converts it into thermal energy) plus heating due to the battery discharging (flying in sport mode heats the battery faster) minus cooling due to air flow (the fan inside). And yes, high attitude has lower density air so the fan is less effective. At 90°F air temp and in full sun, you should start being concerned about battery overheating.
If the battery overheats and you ignore warning messages, the drone may land on it's own. In addition, overheating the battery will shorten its life.
Warm air is less dense than cooler air, but battery issues will be a bigger problem than the reduced lift provided by the warmer air.
There are a host of folks on this forum that worry about keeping their batteries warm enough by the way....
Enjoy your drone!