July was the hottest month on record for the state of Arizona (a very hot state), by nearly 2 degrees Fahrenheit, according to the U.S. government’s National Oceanic and Atmospheric Administration.

In the U.S. Border Patrol’s Tucson Sector, which takes up most of the state’s border miles, the agency apprehended more migrants (about 40,000) than in any single month since April 2008.

That is incredibly dangerous. Migrants face an elevated risk of death by dehydration or heat stroke in the region that, of all nine Border Patrol U.S.-Mexico border sectors, has been the deadliest for migrants over the past 25 years (blue in this chart).

The move to Arizona is recent. It appears to be a shift in response to the Biden administration’s post-Title 42 policies limiting access to asylum: word appears to have gotten out—correctly or not—that turning oneself in to Border Patrol in remote parts of Arizona increases chances of entering the U.S. asylum system without being deported, detained, or forced to wait weeks or months in a Mexican border city.