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Heat wave to scorch Southwest freight markets (with forecast video)

Photo: Jim Allen/FreightWaves

Another heat wave will begin scorching parts of the southwestern United States in a day or two, putting a little more stress on drivers, their trucks and their temperature-sensitive freight.

SONAR Critical Events: Tuesday, August 11, 2020, 8 a.m. EDT; Excessive heat watch (orange-shaded areas)

A heat wave just hit the Southwest in late July. High temperatures in Phoenix, Tempe and Yuma, Arizona the last four days of July ranged from 111 to 119 degrees, 5 to 10 degrees above normal. The same thing happened in El Centro, California.

Daily record highs of 115, 118 and 116 were set in Phoenix on July 29, 30 and 31, respectively. A daily record high of 115 was set in Tempe on July 31.

A potentially major heat wave could begin in these same areas on Thursday, August 13, persisting at least through the weekend. Cloud cover may keep temperatures in check Wednesday, but the extreme heat could start in some areas that day depending on when the cloud cover thins out.


The impending heat wave is a result of the combination of a subtropical ridge of high pressure plus dry, southwesterly winds aloft. Air sinks, expands and heats rapidly under areas of high pressure. The National Weather Service (NWS) is forecasting the high pressure ridge to strengthen as it moves over the region. The NWS has issued an excessive heat watch across the region, forecasting high temperatures of 104 to 118 degrees, depending on exact location.

More specifically, temperatures will peak at 110 to 116 degrees in the Phoenix metropolitan area, including Mesa, Chandler, Tempe and Sun City; 104 to 112 in the Tonto Basin, just east of Phoenix; 108 to 114 in Scottsdale and Apache Junction, Arizona; 111 to 16 in Gila Bend and Yuma, Arizona; and 111 to 118 in El Centro, California.

The heat wave will affect major routes such as interstates 8, 10, 17 and 40. This includes portions of the Ontario, California freight market, which has high levels of reefer loads available, according to the latest FreightWaves data.

Reefers are climate-controlled trailers used to transport temperature-sensitive freight such as produce, as well as beverages and other liquids. Excessive heat can exert extra strain on reefers, so drivers have to make sure their trailers are set at just the right temperature levels.


SONAR ticker: ROTVI

The SONAR map directly above shows that Ontario is a leading market in the Reefer Outbound Tender Volume Index (ROTRI). This indicates that many drivers will be heading into the heat wave to pick up reefer loads in southern California over the next several days.

Click here for more FreightWaves articles by Nick Austin.

Nick Austin

Nick is a meteorologist with 20 years of forecasting and broadcasting experience. He was nominated for a Midsouth Emmy for his coverage during a 2008 western Tennessee tornado outbreak. He received his Bachelor of Science in Meteorology from Florida State University, as well as a Bachelor of Science in Management from the Georgia Tech. Nick is a member of the American Meteorological Society and National Weather Association. As a member of the weather team at WBBJ-TV in Jackson, Tennessee, Nick was nominated for a Mid-South Emmy for live coverage of a major tornado outbreak in February 2008. As part of the weather team at WRCB-TV in Chattanooga, Tennessee, Nick shared the Chattanooga Times-Free Press Best of the Best award for “Best Weather Team” eight consecutive years.