Be careful. I would suggest avoiding spending extended time at that temperature and instead ride in cooler morning/evening.

This past February I cycled in hot desert area of Sudan. One day my cycle computer showed peak temperature of 117F and also that I spent several hours riding riding in excess of 110F. This was part of three very hot days cycling. I ended up with heat exhaustion (throwing up all water in my system and weak) and treated with drip iv to return salt/sugars back into my body. In retrospect, I probably didn't keep replenish enough salt and previous days of hot temperatures diminished appetite and hence also left me with not enough fuel. Some other cyclists riding that day also ended up with heat exhaustion.

My blog journal for that day: http://www.bike2013.com/2013/02/05/day-20-78-of-86-km/

Bodies are going to deal differently with such hot dry temperatures. I know mine would probably be ok for an hour at 115F, but spending more extended time in excess of 110F and/or developing deficit of energy or salt has some real risks. In this case it would be better to instead cycle in relatively cooler periods of the day and not be out riding in the worst heat.

I've also done tours through desert with some times well beyond 100F including two trips going via Las Vegas. One was a ride from San Jose to Las Vegas via Death Valley in early May and another was a supported ride (Las Vegas Hell Week) also in early May. While some cycling was done in hot periods was able to do most of the riding those days in relatively cooler parts of the day.

Overall, I'd suggest when the daily temperatures get up to 115+F to plan things so you don't spent too much of your day cycling at that temperature but instead ride in cooler parts of the day. Also, if possible know how your body might react to extended periods of such heat and how to keep enough fluid and salt and energy in the system.