El Paso, which had previously declared a Strained Operating Condition due to low linepack, late Wednesday issued a drafting-based emergency Critical Operating Condition with a 3% negative imbalance tolerance. "Based on current supply shortfalls caused by extreme cold temperatures and power outages in the production areas...and current demand on the delivery side of the system, [El Paso] does not expect conditions to improve over the next 24 hours," the pipeline said.

Southwest Gas said it was issuing an OFO Thursday effective until further notice due to a low-linepack Alert Day on Transwestern. See the bulletin board for details.

CIG said it will cancel Friday a Strained Operating Condition.

Westcoast has ended a low-linepack OFO, saying levels were back to normal Thursday.

NOVA restored its normal -4/+4 imbalance tolerance range Thursday.

Transwestern extended its systemwide low-linepack Alert Day through at least Friday.

Citing severe weather conditions throughout the southwestern U.S. affecting gas production and interstate pipeline operations, affiliates Southern California Gas and San Diego Gas and Electric said starting at 3 p.m. PST Thursday they were declaring a system emergency and curtailing transmission service "for all interruptible and a number of firm noncore customers located in Riverside, Imperial and San Diego Counties.

Northern Natural Gas allowed a System Overrun Limitation to expire in its market-area zones but is extending it through at least Friday in all field mids (Mids 1-16B) "due to lower-than-normal temperatures and due to the underperformance in receipt gas from various interconnects primarily in the field area."

CenterPoint issued an Operational Alert to maintain system integrity in response to a shortage of supply in its West-1 Pooling Area as a result of colder-than-normal weather.

El Paso said the N.N. Winkler receipt point in the Keystone Pooling Area will remain shut in due to gas quality issues.

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