Family Vacation – Vegas, Grand Canyon, Flagstaff, Springdale – temp/weather specific question

So mid May on the South Rim of the Grand Canyon and surroundings? No, you won't see 32F or 90F. Those are perhaps extremes temps for the month over the recorded decades.

You could see some frost just before sunrise after a clear, windless night. But then stay in the hotel or hop in the car and start your hikes after sunrise – it will warm up quickly. But bring a fleece sweater for the adults and a little more for the kid – warm hat and gloves, because he might be inactive in a child carrier.

I'd plan on days on the South Rim to reach 70-80F although it could be windy. It will be much hotter in the Inner Canyon. I went Rim-River-Rim with my son late last May and got very lucky as the highest we saw was 87F. 100F would have been more typical.

The South Rim is 5000 feet above the River. It is therefore 20F cooler on the Rim. Plus the Inner Canyon offers little shade, you have infared radiating from the hot rocks along the trail and the South Kaibab Trail offers no water until you get to the River itself.

Winter clothes – no. A fleece sweater – yes. More so: good sunhats and sunscreen. The UV is much more intense at 7000 feet.

Gotcha. So I am backwards on the temp in the bottom, for some reason I was thinking it would be colder down there but I'm not used to thinking about altitude.

So this confirmed for me, bring more shorts and tshirts, scratch the winter weather type clothes for the adults at least. I keep thinking Nevada, Arizona, Utah in late May sounds like shorts and t-shirts but maybe I am crazy.

Here is what I am seeing…

http://www.weather.com/weather/tenday/Grand+Canyon+AZ+USAZ0088:1:US