The threat of another blast of bitterly cold arctic air bearing down on the U.S. is sending natural-gas futures prices to their highest level in more than a year.
Traders and investors who had bet on falling natural-gas prices are being squeezed and have had to scramble to buy back contracts they once sold to close out their positions, pushing prices this week to their highest level since late 2016.
The February contract gave up some of those gains Thursday, falling 1.8% to $3.4470 a million British thermal units. Natural gas for March delivery—which will become the front-month contact next week—rose 0.6% to $3.099 per million BTUs.
The surge came as weather forecasts predicted that the warm temperatures in the latter part of January will abruptly give way to another wave of intense cold from the Midwest down to Texas and eastward, as a high-pressure ridge over Alaska appears set to send arctic air down through North America.
“The market was antsy, waiting for that first clear sign of cold. [Tuesday] it arrived,” said Jacob Meisel, chief weather analyst at Bespoke Weather Services.
The cold could strain natural-gas supplies, which have already been depleted by record-low temperatures across much of the country early this month. A severe winter storm known as a “bomb cyclone” hammered the East Coast in the first days of the year. Then, in the southern U.S., snow, sleet and freezing rains scuttled flights, canceled school days, and created hazardous driving conditions.
That resulted in record demand for gas: During the first week of the year, 359 billion cubic feet was withdrawn from storage, according to the U.S. Energy Information Administration. The demand, coupled with infrastructure bottlenecks, prompted a swift run-up in natural-gas prices on the spot market in some places. At a New York hub, for example, prices rose as high as $175 per million BTUs during trading on Jan. 5, according to S&P Global Platts.
That is prompting some usual movements of superchilled liquefied natural gas, making shipments from as far away as Siberia look economical.
Engie SA bought a cargo of LNG from a facility in the U.K. to supplement the regular supply at its Boston import terminal. The cargo likely includes gas from Russia’s new LNG export facility, an Engie spokeswoman said—the first time the U.S. has imported gas from Russia, according to U.S. Department of Energy data.
Another wave of bitter cold could prompt a repeat, analysts said. “The concern is in February, deliverability gets even more constrained versus the January event,” said Joel Stier, a trader at StierBull Trading LLC.
The amount of natural gas in storage is 17.5% below the five-year average, after another big withdrawal from inventories last week.
Supplies are particularly tight in the South and the East, where temperatures are expected to plunge early in February. The amount of gas sitting in the Southeast’s underground salt caverns—the most readily accessible sort of supply—was recently at its lowest point for this time of year since the polar vortex in 2014.
“Storage is low—precariously low,” said Bill Perkins, who runs the natural-gas-focused fund Skylar Capital Management LP.
That has some end-users, such as utilities, trying to stock up so they have enough gas available to keep their customers’ homes warm if the predicted cold arrives, analysts and traders said.
Mr. Perkins said he is cautiously bullish on gas prices, “with both eyes on the weather.”
The latest shift in weather forecasts has caught some speculators flat-footed. Winters have been mild the last two years, leading to tepid demand for heating fuel. At the same time, natural-gas production has been surging to new records—something that investors believed would keep the market well supplied even in cold weather.
John Woods, president of JJ Woods Associates and a Nymex trader, said he was taken aback by how high prices rose—he sold when prices rose to around $3.22 to $3.25 per million BTUs.
“That one hurt,” he said of missing the rest of the run-up.
At the end of 2017, hedge funds and other money managers were betting that natural-gas prices would fall: Short bets on natural gas outnumbered long ones by more than 50,000 contracts. Natural-gas prices fell to a 10-month low of $2.598 a million BTUs in late December. Since then, though, these investors have become more bullish.
What market participants weren’t thinking about was demand, said Kyle Cooper, an analyst at Ion Energy Group.
“The whole mantra has been supply, supply, supply,” he said. “Mother Nature just squeezed you again.”