April 18 (Reuters) - The amount of natural gas flowing to the seven U.S. liquefied natural gas (LNG) export plants, including Freeport LNG, was on track to jump by around 17% on Thursday from a 15-month low on Tuesday, data from financial firm LSEG showed.

LNG feedgas rose to a preliminary 10.8 billion cubic feet per day (bcfd) on Thursday, up from 10.1 bcfd on Wednesday and a 15-month low of 9.2 bcfd on Tuesday when feedgas to several facilities dropped, including Freeport in Texas, Cameron LNG in Louisiana, and Cheniere Energy's Sabine Pass in Louisiana and Corpus Christi in Texas.

Since Tuesday, gas flows have increased at all of those plants. Energy traders said increased flows to Freeport was a sign that at least one of the plant's three liquefaction trains was starting to exit an outage.

Feedgas at Freeport was on track to reach 0.3 bcfd on Thursday, according to LSEG data, up from near zero seen over the past week or so since Freeport Train 3 tripped on April 9, according to an emissions report the company filed with Texas environmental regulators on April 10.

Officials at Freeport had no comment on the latest increase in feedgas.

In late March, Freeport said it expected two of the three liquefaction trains at the plant, Trains 1 and 2, to remain shut until May for inspections and repairs, while Train 3 was operating.

Each Freeport train can turn about 0.7 bcfd of gas into LNG.

One billion cubic feet is enough gas to supply about five million U.S. homes for a day.

The startup and shutdown of Freeport and other U.S. LNG export plants has often had a major impact on global gas prices.

Worries about a possible decline in gas supplies following the drop in feedgas to U.S. LNG export plants on Tuesday helped boost gas futures in Europe by around 6% at the Dutch Title Transfer Facility (TTF).

Overall gas flows to the seven big U.S. LNG export plants have slid to an average of 11.9 bcfd so far in April, down from 13.1 bcfd in March. That compares with a monthly record of 14.7 bcfd in December. (Reporting by Scott DiSavino Editing by Chris Reese)