By Scott DiSavino

March 26 (Reuters) - U.S. natural gas futures edged up about 1% on Wednesday on record gas flows to liquefied natural gas export plants and forecasts for higher demand over the next two weeks than previously expected.

That price increase came despite record output and forecasts for milder weather to continue through mid April.

On its second to last day as the front-month, gas futures NGc1 for April delivery on the New York Mercantile Exchange rose 3.7 cents, or 1.0%, to $3.877 per million British thermal units (mmBtu). On Tuesday, the contract closed at its lowest since February 28 for a second day in a row.

Despite forecasts for more demand over the next two weeks, traders noted that mild weather should allow utilities to keep adding fuel to storage this month.

Some analysts said gas stockpiles were on track to increase in March for the first time since 2012 and only the second time in history.

Gas stockpiles, however, were still about 8% below normal levels for this time of year after extremely cold weather in January and February forced energy firms to pull large amounts of gas out of storage, including record amounts in January. EIA/GAS NGAS/POLL

In the spot market, gas prices at the Waha Hub NG-WAH-WTX-SNL in the Permian shale in West Texas turned negative for the second time this month due to pipeline maintenance that trapped gas associated with oil production in the basin.

With Permian oil production hitting record highs every year since at least 2016, according to data from the U.S. Energy Information Administration and the Federal Reserve Bank of Dallas, energy firms have had a hard time building gas pipes fast enough to keep up with soaring associated gas output. Permian gas production has also hit record highs every year since at least 2018.

Pipeline constraints have caused next-day Waha prices to turn negative a record 49 times in 2024. Waha prices averaged below zero 17 times in 2019, six times in 2020 and once in 2023.

SUPPLY AND DEMAND

Financial firm LSEG said average gas output in the Lower 48 U.S. states rose to 106.0 billion cubic feet per day so far in March, up from a record 105.1 bcfd in February.

Meteorologists projected temperatures in the Lower 48 states would remain mostly warmer than normal through April 10.

With seasonally milder weather coming, LSEG forecast average gas demand in the Lower 48, including exports, will slide from 108.3 bcfd this week to 104.1 bcfd next week. Those forecasts were higher than LSEG's outlook on Tuesday.

Gas flowing to the eight big operating U.S. LNG export plants rose to an average of 15.8 bcfd so far in March from a record 15.6 bcfd in February as new units at Venture Global's VG.N 3.2-bcfd Plaquemines LNG plant under construction in Louisiana entered service and the return of Freeport LNG in Texas from a one-day outage.

The U.S. became the world's biggest LNG supplier in 2023, surpassing Australia and Qatar, as surging global prices fed demand for more exports due in part to supply disruptions and sanctions linked to Russia's 2022 invasion of Ukraine.

Gas traded around $13 per mmBtu at both the Dutch Title Transfer Facility (TTF) TRNLTTFMc1 benchmark in Europe and the Japan Korea Marker (JKM) JKMc1 benchmark in Asia. NG/EU

(Reporting by Scott DiSavino;Editing by Alison Williams)

((scott.disavino@thomsonreuters.com; +1 332 219 1922; Reuters Messaging: scott.disavino.thomsonreuters.com@reuters.net))

For gas data on the LSEG terminal type ENERGY in the search bar and then go to the GAS drop down and the NORTH AMERICA drop down.

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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