could you tell me what the weather normally is in the Las Vegas area mid to late April? FI and I will be going to the Mustang 50th anniversary April 16-20, then meeting his mom and his daughter on the 20th-30th (I'm flying back home on the 25th to go back to school). When the four of us are together, we're planning to go either to the Grand Canyon, Zion Canyon, or maybe Yosemite. Any recommendations there would be pretty awesome too