Despite soaring temperatures across much of the West late in the week, particularly in California, weekly gas prices tumbled, driven lower by steep declines early in the period as cloud cover spanned parts of the western and southern United States and cooler temperatures moved into the nation’s midsection.

Without air conditioners cranking early in the week, NGI’s Weekly Spot Gas National Avg. for the Aug. 31 to Sept. 4 period declined 12.5 cents to $2.115

Intense late-summer heat took hold during the week in the West – with more expected over the long Labor Day weekend – gripping large swaths of California and much of the Southwest. Lofty temperatures also permeated Texas and parts of the Southeast, adding to strong overall cooling demand. But the surging temperatures...