As Trump Rallies in the Southwest, Extreme Heat Threatens MAGA Faithful

Political campaigns do their best to control as much as possible: their candidate, their messaging, their surrogates and their schedules. But what to do about the weather?

This week, with former President Donald J. Trump holding campaign events in the Southwest, his team is grappling with an extreme heat wave that has threatened the health of some of his most ardent fans.

On Thursday, Mr. Trump went to Phoenix for a campaign event at a megachurch, where hopeful attendees waited for hours to enter as the temperature climbed above 110 degrees. The heat was so scorching that some of those waiting collapsed, and 11 people were taken to hospitals to be treated for heat exhaustion.

The Trump campaign is taking steps to avoid similar circumstances on Sunday, when Mr. Trump is scheduled to speak at an outdoor rally at noon at a park in Las Vegas. Forecasts expect the temperature to be around 105 degrees.

Much of the western United States has been contending with a heat wave all week. Both Phoenix and Las Vegas have been under an excessive heat warning for days, with afternoon temperatures hovering in the triple digits.