Spot natural gas prices strengthened in the final full week of May as power burns remained robust even as demand in the South Central region retreated along with temperatures. With a brief heat wave stoking East Coast demand – and another blast of cold hitting the West Coast – NGI’s Weekly Spot Gas National Avg. jumped 42.0 cents to $8.340.

The National Weather Service said several fronts were expected to impact the Pacific Northwest, Rockies and Northern Plains in the next few days. Thunderstorms and heavy rains were likely, along with snow in some areas.

The chilly weather sent cash prices higher for the May 23-27 trading period, with gains of more than $1.00 in California. SoCal Citygate traded in a wide band from $8.210-$10.300 before averaging $9.320, up $1.115...