NEW YORK — Natural gas, the nation’s most prevalent heating fuel, is getting cheaper just as winter is arriving because of mild temperatures and plentiful supplies.

The price of natural gas has dropped 29 percent in a month, to $3.17 per 1,000 cubic feet on Tuesday from nearly $4.50 in late November. That’s a steep drop even for a fuel notorious for volatile price swings.

The lower prices are expected to linger and could reduce electricity prices and heating bills in the coming months. Natural gas is used by half of the nation’s households for heating and to generate 26 percent of the nation’s electricity.

Bob Brackett, an analyst at Bernstein Research, wrote in a recent note to investors that he expects natural gas to average “in the low 3’s” into the spring, and a warm winter could push the price below $3.

Last year at this time natural gas was near $4.50 and it reached as high as $6.15 in February.

Because of the way natural gas and electric utilities are regulated, customers won’t likely see the recent drop reflected in their bills right away. Many will instead see higher prices as a result of last year’s price spike.

But the lower market prices could at least slow the rise in retail prices and perhaps reverse it if the low prices last.