Adds EIA storage report, latest prices

By Scott DiSavino

May 15 (Reuters) - U.S. natural gas futures slid about 2% to a two-week low on Thursday on a bigger-than-usual weekly storage build and forecasts for less demand next week than previously expected.

Gas futures NGc1 for June delivery on the New York Mercantile Exchange fell 5.3 cents, or 1.5%, to $3.439 per million British thermal units by 10:33 a.m. EDT (1433 GMT), putting the contract on track for its lowest close since April 30.

The U.S. Energy Information Administration $(EIA)$ said energy firms added 110 billion cubic feet (bcf) of gas into storage during the week ended May 9.

That was in line with the 109-bcf build analysts forecast in a Reuters poll and compares with an increase of 73 bcf during the same week last year and a five-year average build of 83 bcf for this time of year. EIA/GAS GAS/POLL

Analysts said last week's build was much bigger than usual because mild weather kept both heating and cooling demand for gas lower than usual for this time of year.

Despite a heat wave coming to Texas this week, analysts said heating and cooling demand should remain low across much of the rest of the country in coming weeks, allowing utilities to keep injecting more gas into storage than normal for this time of year.

Gas stockpiles were currently around 3% above the five-year (2020-2024) normal. EIA/GAS GAS/POLL

SUPPLY AND DEMAND

Financial firm LSEG said average gas output in the Lower 48 U.S. states fell to 103.6 billion cubic feet per day so far in May, down from a monthly record of 105.8 bcfd in April.

On a daily basis, gas output was on track to drop from a record 107.4 bcfd on April 18 to a preliminary 11-week low of 102.2 bcfd on Thursday. Analysts have noted that preliminary data is often revised later in the day.

Meteorologists projected temperatures in the Lower 48 states would remain mostly warmer than normal through May 30.

After hitting 90 degrees Fahrenheit (32.2 Celsius) on Tuesday and Wednesday, AccuWeather meteorologists forecast temperatures in Houston, the biggest city in Texas, would reach 95 F on Thursday, breaking the May 15 record high of 94 F set in 1978, and would keep hitting the 90s F every day from May 13-18. The normal high in the city at this time of year is 86 F.

LSEG forecast average gas demand in the Lower 48, including exports, will hold around 96.4 bcfd this week and next. The forecast for next week was lower than LSEG's outlook on Wednesday.

The average amount of gas flowing to the eight big LNG export plants operating in the U.S. fell to 15.1 bcfd so far in May, down from a monthly record of 16.0 bcfd in April.

The LNG feedgas decline so far this month was mostly due to reductions for maintenance at Cameron LNG's 2.0-bcfd plant in Louisiana and Cheniere Energy's LNG.N 3.9-bcfd Corpus Christi plant under construction and in operation in Texas, and a one-day outage at Freeport LNG's 2.1-bcfd plant in Texas on May 6.

LNG gas flows to the Corpus Christi facility were on track to hold at a two-month low of 1.5 bcfd for a second day in a row on Thursday, down from 1.6 bcfd on Tuesday and an average of 2.0 bcfd during the prior seven days, according to LSEG data.

(Reporting by Scott DiSavino; Editing by Kirsten Donovan and Susan Fenton)

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

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

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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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