Emerging Heat in the Medium-range is a Problem…May Lock-in and Spread

Fig. 1: NOAA/CPC extreme heat risk areas ahead.

Discussion: NOAA/CPC indicates a large region of excessive to extreme heat during the medium-range for California, the Interior West and especially the Southwest U.S. and Great Plains to the East-central States. Hottest temperatures are in the Southwest Desert when 110’s is common in 9 days. Additionally, afternoon temperatures make a run at 110F in Oklahoma (and vicinity) at the same time. Excessive heat will reach into the northern states from Oregon to Indian in the 8-14/11-15-day period.

This scenario is a major problem for U.S. energy. Obviously, the excessive heat across ERCOT and especially SPP may produce some records. The larger concern is the ability of extreme heat in July to dry-out soils rapidly which contributes to feedback into the atmosphere that amplifies the upper ridge, sustains the heat and can make already hot temperatures hotter.

This risk will widen its aerial coverage during mid-summer most effective across areas with dry soils.

Notice that the East is unaffected. When that upper trough in Eastern Canada lifts northward or weakens, the Central U.S. heat will ride eastward fast, down-sloping the Appalachians and producing extreme heat most-focused on the Mid-Atlantic States. We don’t see that scenario yet but it’s on the way.