SAN DIEGO (Border Report) — So far this summer, the Mexican city of Mexicali has registered 21 deaths due to the hot weather.

This is the highest “heat death toll” in recent years according to Óscar Efrén Zazueta Fierro, the head of epidemiology for the border state of Baja California.

The ages of the people who have died range from 18 to 61.

Zazueta Fierro says there have also been 393 recent cases of heatstroke. He and other officials are asking residents to remain hydrated and out of the sun as much as possible.

In Mexicali, which is just south of the border about 120 miles east of San Diego, the average temperature over the last 45 days has been 115 degrees Fahrenheit, and mercury is not expected to drop in the near future.

The city has been hit by warmer than normal temperatures this year, at times reaching a high of 122 degrees.