Adds latest prices

By Scott DiSavino

Sept 23 (Reuters) -U.S. natural gas futures jumped about 7%to a 12-week high on Monday on worries some Gulf Coastoil and gas producers would reduce output ahead of a possible hurricane that could hit the region later this week.

Front-month gas futures NGc1 for October delivery on the New York Mercantile Exchange rose 17.9 cents, or 7.4%, to settle at $2.613 per million British thermal units (mmBtu), their highest close since June 27.

That was the contract's biggest daily percentage gain since late August andpushed the front-monthinto technically overbought territory for the first time since the middle of June.

In the Atlantic basin, the U.S. National Hurricane Center (NHC) forecast a tropical disturbancein the Caribbean Sea would strengthen intoa hurricane on Wednesday that would hit the Florida Panhandle on Thursday.

Although storms aremore likely to reduce gas demand and prices through poweroutages and shuttingliquefied natural gas (LNG) export plants, analysts said this storm was currently on track to miss the LNG plants.

That means demand for gas from those LNG export plants was likely to remain high at the same time some Gulf Coast producers cut output.

More than75% of U.S. gas production still comesfrom big inland shale basins like Appalachia in Pennsylvania, West Virginia and Ohio and the Permian in West Texas and eastern New Mexico, so most of the country's gas output should remain safe from the storm.

That is very different from 20 years ago when roughly 20% of the nation's gas came from the federal offshore parts of the Gulfof Mexico. Back then, Gulf Coast hurricanes usually caused gas prices to spike higher.

Now, however,the federal offshoreregion produces just about2% of the country's gas.

In Canada, meanwhile, next-day gas prices at the AECO hub NG-ASH-ALB-SNL in Alberta fell to 5 cents per mmBtu, their lowest level since hitting a record low of around 2 cents in August 2022, according to data from financial firm LSEG going back to 1993.

SUPPLY AND DEMAND

LSEG said gas output in the Lower 48 U.S. states has slidto an average of 102.1 billion cubic feet per day (bcfd) so far in September, down from 103.2 bcfd in August.

With milder autumn weather coming, LSEG forecast average gas demand in the Lower 48 states, including exports, will slide from 99.1 bcfd this week to 97.7 bcfd next week. Those forecasts were lower than LSEG's outlook on Friday.

Gas flows to the seven big U.S. LNG export plants have easedto an average of 12.8 bcfd so far in September, down from 12.9 bcfd in August. That compares with a monthly record high of 14.7 bcfd in December 2023.

That reduction was due mostly to the planned Sept. 20 shutdownof Berkshire Hathaway Energy's 0.8-bcfd Cove Point LNG export plant in Maryland for around three weeks of annual maintenance.

Reporting by Scott DiSavino; Editing by Paul Simao

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.

For Interactive Map, type 'Interactive Map' in the box at upper left of the LSEG 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

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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