March 11 (Reuters) - U.S. natural gas prices slipped more than 1% on Tuesday, as rising output and forecasts for milder weather offset a higher demand outlook for next week and record flows to liquefied natural gas $(LNG)$ export facilities.

Front-month gas futures NGc1 for April delivery on the New York Mercantile Exchange were down 5.7 cents, or 1.3%, at $4.433 per million British thermal units (mmBtu) as of 9:58 a.m. EDT (1358 GMT). Prices rose to their highest level since December 2022 on Monday.

"With the weather factor diminishing in importance with near-record temperatures expected across some key consuming regions this week, further downward adjustment in HDD (heating degree days) accumulation would normally be pressing values lower," energy advisory firm Ritterbusch and Associates said in a note.

Financial firm LSEG estimated 213 heating degree days over the next two weeks in the Lower 48 U.S. states, down from the 221 HDDs estimated on Monday. The normal level is 278 HDDs for this time of year. Meteorologists projected weather in the Lower 48 states would remain mostly warmer than normal through March 15.

LSEG said average gas output in the Lower 48 U.S. states has risen to 105.7 billion cubic feet per day (bcfd) so far in March, up from a record 105.1 bcfd in February.

However, LSEG forecast average gas demand in the Lower 48 states, including exports, will rise from 110.4 bcfd this week to 113.3 bcfd next week. Forecasts for next week were higher compared to LSEG's outlook on Monday.

Dutch and British wholesale gas prices rose on Tuesday amid lower Norwegian exports to Europe and higher demand. NG/EU

Gas prices rose more than 14% last week on record flows to LNG plants and worries Canada would reduce power and gas exports to the U.S. after U.S. President Donald Trump imposed tariffs on Canada and Mexico on March 4. Trump later said the two trading partners would not have to pay tariffs until early April on any goods that fell under the United States-Mexico-Canada Agreement.

In 2024, Canada supplied about 8% of total U.S. gas demand, including exports, and about 1% of total U.S. power demand, again including exports. Some of those power and gas exports returned to Canada.

In the import market, Canadian gas exports to the U.S. have dropped to an average of 8.8 bcfd over the past few days since Trump's tariffs were imposed, down from an average of 9.8 bcfd during the prior 11-day period from February 21 to March 3, according to LSEG data.

That compares with an average of 8.6 bcfd of Canadian gas exports to the U.S. in 2024 and 7.6 bcfd over the prior five years (2019-2023).

The amount of gas flowing to the eight big U.S. LNG export plants has risen to an average of 15.7 bcfd so far in March, up from a record 15.6 bcfd in February, as new units at Venture Global's VG.N 3.2-bcfd Plaquemines LNG export plant under construction in Louisiana enter service.

"We continue to expect 2026 Henry Hub prices to remain above $4/mmBtu to incentivize drilling increases in the Haynesville region, the current source of marginal U.S. dry gas production growth, to help keep storage comfortable in the 2026/27 winter as U.S. LNG exports continue to move higher," Goldman Sachs said in a note.

text_section_type="notes">For Interactive Map, type 'Interactive Map' in the box at upper left of the LSEG terminalFor graphics on Baker Hughes rig counts, see: http://graphics.thomsonreuters.com/15/rigcount/index.htmlFor next-day SNL U.S. gas prices, see: 0#SNL-NGFor next-day SNL U.S. power prices, see: 0#SNL-PWRFor U.S. natgas price and storage polls, see: NGAS/POLLFor U.S. nuclear power outages, see: NUKE/For U.S. Northwest hydro power report, see: NWRFCFor U.S./Canada natural gas rig count vs Henry Hub futures price, see: http://tmsnrt.rs/2eT9k44For the U.S. natural gas speed guide, see: USGASFor the U.S. power speed guide, see: USPOWERTo 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#3CFTC023651NYMEX Henry Hub futures only 0#1CFTC023651ICE Henry Hub options and futures combined 0#3CFTC023391NYMEX Henry Hub swaps options and futures combined 0#3CFTC03565BNYMEX Henry Hub Penultimate gas swaps 0#3CFTC03565C

(Reporting by Brijesh Patel and Anmol Choubey in Bengaluru; Editing by Paul Simao)

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