UPDATE 2-U.S. natgas gains 3% as winter storm persists

Updates prices

Feb 17 (Reuters) - U.S. natural gas futures rose nearly 3% on Wednesday to a more than three-month high, extending its rally to a third session as a cold snap continued to wreak havoc on the energy industry and fuel soaring demand for heating.

Front-month gas futures NGc1 rose 9.0 cents, or 2.9%, to settle at $3.219 per million British thermal units, shaking off initial declines, which analysts attributed to forecasts suggesting a likely reprieve from the deep freeze next week.

Prices jumped over 10% on Tuesday to hit a high since Nov. 3 at $3.214.

"The current cold snap is expected to take a heavy toll on amount of gas available now and also down the road," said Zhen Zhu, economist at Oklahoma City-based C.H. Guernsey.

"The spike in the consumption coupled with the continued decline in production makes the gas market tighter than before."

Unusually freezing weather is likely to wreak havoc on U.S. oil and gas production for several days, if not weeks, according to industry experts, as companies deal with frozen equipment and a lack of power to run operations. nL1N2KM1Z3

The deep freeze left millions without power along the U.S. Gulf Coast, causing power prices to surge, especially in Texas - the country's biggest oil and natural gas producer.

Next-day power for Wednesday at the ERCOT North hub EL-PK-ERTN-SNL, which includes the cities of Dallas and Fort Worth, spiked to a record of $8,800 per MWh, a nearly sixfold jump from $1,490 on Tuesday. nL4N2KN2NU nL8N2KN026

Next-day prices at Waha hub in the Permian basin in West Texas NG-WAH-WTX-SNL also hit an all-time peak of $209.75 per mmBtu. Power at PJM Western Hub EL-PK-PJMW-SNL hit a high since January 2018.

Daily U.S. natural gas production has fallen by roughly 17% from the end of last week to 72.1 billion cubic feet per day on Wednesday, according to preliminary data from Refinitiv Eikon. nL1N2KL0HR

Data provider Refinitiv estimated 401 heating degree days (HDDs) over the next two weeks in the Lower 48 U.S. states, slightly down from Tuesday's forecast of 425 HDDs.

The normal is 374 HDDs for this time of year. HDDs measure the number of degrees a day's average temperature is below 65 degrees Fahrenheit (18 degrees Celsius). The measure is used to estimate demand to heat homes and businesses.

Prices will be susceptible to selling in the coming days as temperatures ease, said Daniel Myers, market analyst at Gelber & Associates in Houston.

Meanwhile, Refinitiv projected average demand, including exports, would ease to 122.2 to billion cubic feet per day (bcfd) next week from this week's 144.4 bcfd, while staying above the five-year average of 107.2 bcfd.

(Reporting by Bharat Govind Gautam and Eileen Soreng in Bengaluru; editing by Jonathan Oatis and Richard Chang)

((eileen.soreng@thomsonreuters.com; Within U.S. +1 646 223 8780, Outside U.S. +91 80 6749 6131; Reuters Messaging: eileen.soreng.thomsonreuters.com@reuters.net))

For Refinitiv, formerly Thomson Reuters Supply Chain & Commodities Research (SC&CR), type ENERGY in Eikon search bar and then go to the GAS dropdown and the NORTH AMERICA dropdown or see: cpurl://apps.cp./cms/?pageid=usa-gas

For Thomson Reuters Interactive Map, type 'Interactive Map' in the box at upper left of the Reuters Eikon terminal.				

For graphics on Baker Hughes rig counts, see: http://graphics.thomsonreuters.com/15/rigcount/index.html

For next-day SNL U.S. gas prices, see: 0#SNL-NG				

For next-day SNL U.S. power prices, see: 0#SNL-PWR

For U.S. natgas price and storage polls, see: NGAS/POLL

For U.S. nuclear power outages, see: NUKE/				

For U.S. Northwest hydro power report, see: NWRFC				

For U.S./Canada natural gas rig count vs Henry Hub futures price, see: http://tmsnrt.rs/2eT9k44

For the U.S. natural gas speed guide, see: USGAS

For the U.S. power speed guide, see: USPOWER

To determine CFTC managed money net position add (NYMEX Henry Hub options and futures combined 3023651MNET) plus (ICE Henry Hub options and futures combined 3023391MNET divided by four) plus (NYMEX Henry Hub swaps options and futures combined 303565BMNET divided by four) plus (NYMEX Henry Hub penultimate gas swaps 303565CMNET divided by four)

NYMEX Henry Hub options and futures combined 0#3CFTC023651

NYMEX Henry Hub futures only 0#1CFTC023651

ICE Henry Hub options and futures combined 0#3CFTC023391

NYMEX Henry Hub swaps options and futures combined 0#3CFTC03565B

NYMEX Henry Hub Penultimate gas swaps 0#3CFTC03565C