Wear layered clothing and watch for changing conditions. Lightning is a common occurrence. Afternoon thundershowers are frequent in the summer. Stay inside during a lightning storm. If you re in a car, keep the windows closed.
Rain can come suddenly.
Bring appropriate gear for rain or snow. Watch for flooding in gullies or washes. The air here is very dry. Drink plenty of fluids. Use skin lotions and lip balms to combat dryness or chapping.