Fox News Weather Center

Sweltering heat to enhance wildfire threat in southwestern US this week

Unseasonably hot weather that overspread the southwestern United States this past weekend will fail to relinquish its grip on the region this week.

Temperatures in most valley locations are expected to soar well above 100 degrees Fahrenheit on a daily basis this week.

“An expansive dome of heat will continue to build across the southwestern U.S. through midweek and lead to near-record high temperatures for many locations across the Four Corners region,” according to AccuWeather Meteorologist Brett Rossio.

In some cases, temperatures will be running 5-15 degrees above normal for the first half of June, Rossio added.

Southwest heat static

Residents in Phoenix can expect high temperatures to exceed 105 F through Friday, which is over 5 degrees above normal for early June.

Similarly, the mercury is forecast to soar to between 100 and 105 degrees in Las Vegas through Thursday.

The extreme heat will peak in both intensity and coverage on Wednesday, when temperatures may approach the daily record of 100 F in Salt Lake City.

Areas in the central Rockies can expect to see the greatest temperature departures this week. Although the highest temperatures will remain over the Desert Southwest, a hot, southerly flow of air will pump the extreme heat much farther north than normal for early June.

In fact, 90-degree heat will soar northward to the Canadian border by both Wednesday and Thursday.

Extremely low humidity values will hold AccuWeather RealFeel® temperatures within a few degrees of the actual temperatures throughout the Southwest this week.

Even though the low humidity may make the heat seem less extreme to some, it will pose a double-edged sword to residents of the Southwest.

“The very dry weather, humidity values below 10 percent and extreme heat can combine to elevate the potential wildfire risk across the Southwest this week,” Rossio said.

When both soil and vegetation dry out, the risk for wildfires is greatly enhanced since dry forests ignite much more quickly than moist ones.

Any spark from a campfire or cigarette can trigger a fire that can quickly expand out of control and threaten both lives and property.

Residents living in the burn-prone regions of interior Southern California and the foothills north of Phoenix should be prepared for potential wildfires and have an evacuation plan in place if necessary.

In addition to the enhanced wildfire threat, anyone spending an extended amount of time outdoors should make sure to drink plenty of fluids in order to avoid heat exhaustion or heat stroke.

Young children and the elderly should be especially cautious this week, as these age groups are most likely to succumb to the heat and fall ill with heat-related illnesses.

The unseasonably hot air will not reach the beaches of central and Southern California. A cool flow of air off the Pacific Ocean will hold temperatures in the 60s and 70s along the immediate California coastline.

By the end of the upcoming weekend and into the beginning of next week, the dome of high pressure will weaken and shift eastward, allowing temperatures to fall back to normal levels for early June.