Las Vegas, Phoenix, and Tucson will all see high temperatures exceed 100 degrees, and all three are likely to tie or break their daily record high temperatures. In Texas, cities including Dallas, San Antonio, and Lubbock will all reach at least 100 degrees.
In total, over 25 cities could break records Sunday and Monday.
The criteria changes again in the Southwestern desert.
Since it’s so hot for much of the year in the Southwest, NWS offices there do not issue heat advisories for desert locations, only excessive heat warnings.
The Las Vegas office is special in that it forecasts for the highest and lowest elevation points in the contiguous US: Mount Whitney and Badwater Basin in Death Valley, respectively.
“Death Valley regularly exceeds 115 degrees in the summer but areas like Mount Whitney do not,” says Jenn Varian, meteorologist at NWS in Las Vegas. “So elevation, the type of terrain out West and even the time of year play a major role in how we issue these excessive heat warnings.”
A few southwestern NWS offices also take into account the number of tourists that come to the city and the transient population that’s unaccustomed to the extreme desert heat.
“Many tend to seek higher terrain in an attempt to escape the heat,” Varian explains. “While you’ll find relief from triple-digit temperatures, the mountains of southern Nevada are still expected to be well-above their seasonal averages as well. As a result, extra heat precautions must be taken even if you are in higher elevations or mountainous regions.”
Nighttime temperatures are also important
Over 20 locations could break record hot low temperatures Sunday through Tuesday.
Safety is key
The purpose of the advisories and warnings is to protect the public and…