There was “some price volatility” associated with a series of Southern California earthquakes and aftershocks that occurred over the Fourth of July weekend, the U.S. Energy Information Administration said, but Southern California gas transmission and distribution systems were largely unaffected.

Southern California Gas Co. reported “no significant impact” to the natural gas system.

Following other recent quakes, a magnitude 4.9 earthquake, centered in Ridgecrest, was reported July 12 by the U.S. Geological Survey.

SoCal Border natural gas prices increased $1.02 to $2.73/MMBtu in July 4 to July 11 trading, while SoCal CityGate values jumped $1.08 to $2.95/MMBtu. For comparison, PG&E CityGate natural gas gained 93 cents to reach $2.87/MMBtu in the trading period.

Western natural gas prices may have gained between 63 cents and $1.18, but still failed to trade above the $3 mark. The greatest price increase among Western natural gas hubs was seen at El Paso-Permian Basin, which jumped from negative pricing to $1.11/MMBtu, a $1.18 leap.

EIA did not mention any distribution disruptions due to a series of earthquakes in western Washington state. The tremors, the strongest of which was a magnitude 4.6 shaker recorded early July 12, were reportedly felt in British Columbia.

The extent to which severe Gulf Coast weather could affect natural gas production and distribution remains a large question mark as Tropical Storm Barry approaches. The EIA estimates production is down 50 percent week over week thanks to temporary shutdowns, adding that “heavy rains, cooler weather, and potential infrastructure outages because of flooding could reduce natural gas demand.”

Working natural gas in storage was 2,471 Bcf as of July 5, according to the EIA. This is a net increase of 81 Bcf compared with the previous week.

Henry Hub gas spot prices jumped 24 cents in July 4 to July 11 trading, ending at $2.48/MMBtu.

Meanwhile, Western daytime power prices gained between $4 and $12.70 in the holiday-extended July 3 to July 11 trading period. Markets were closed Thursday, July 4. South of Path 15 peak power gained the most, up $12.70 to $35.80/MWh. By July 11, Western peak prices ranged from $29.10/MWh at Mid-Columbia to $43/MWh at Palo Verde.

Western off-peak prices followed suit, increasing between $2.80 and almost $8. North of Path 15 gained the most, adding $7.90 to reach $29.50/MWh. Both NP15 and Palo Verde experienced a 37-percent gain in trading. Palo Verde off-peak power ended at $22.95/MWh.

California Independent System Operator demand reached 37,123 MW July 11; however, the week’s high demand may occur July 12, when demand is forecast to reach 39,076 MW.

Total renewables on the CAISO grid reached 17,455 MW July 8, meeting almost 58 percent of demand.