Supplies ran dry at a small-but-growing number of gas stations across the United States yesterday as Gulf Coast refiners and pipelines remained hobbled by Hurricane Katrina and motorists nervous about tightening supplies lined up to top off their tanks.

Most of the stations with "Out of Gas" signs and yellow caution tape draped across their pumps were concentrated along the East Coast and in the Midwest. Station owners said many of the shortages were temporary, exacerbated by panic buying and delays.

A few stations turned off pumps because wholesale prices were rising so fast that they were selling fuel at a loss, even as prices spiked overnight to levels well above $3 a gallon.

The governors of Georgia, North Carolina and Pennsylvania urged motorists to conserve fuel and they warned retailers about alleged price gouging. President Bush also called for conservation and sought to calm motorists, saying Katrina would only cause a "temporary disruption" to the supply of gasoline.

Gas stations ran dry in many states, including Alabama, Arizona, Florida, Georgia, Illinois, Indiana, Massachusetts, North Carolina, Pennsylvania, Virginia, West Virginia and Wisconsin.

Anita Mangels, spokeswoman for the Western States Petroleum Association, said Western Washington is supplied with gasoline from refineries within the state and from crude that comes from Alaska and Canada.

But there is no way to predict what might happen to supplies and prices, she said.

"The thing that everyone is waiting to see is ... the extent of the impact that is going to come out of the Gulf [of Mexico]," she said. "They're still trying to get a handle on what the damage is."

When refineries are shut down for maintenance, Mangels said, the shutdowns are planned and monitored for safety and to avoid damaging equipment. "So when you have an unexpected shutdown, there's a real shock wave that goes through the system," she said.

Resort hotels, meanwhile, reported cancellations as some drivers opted to stay home instead of facing uncertain gas supplies over the Labor Day weekend. And no matter what the underlying causes of the worst gasoline supply crunch since the 1970s, many consumers were alternately incredulous and irate.

"I've never seen anything like this," said Robert Weems, 47, who waited in line for three hours yesterday morning at a gas station 25 miles north of Jackson, Miss., before the pumps ran dry. "It's a black mark on our energy policy; one storm wiping us out like this."

Frustration also ran high in cities far from Katrina's path, where the supply of gasoline, diesel and other fuels continued to tighten because of power outages that have stymied Gulf Coast pipelines and refineries.

"Out of our 34 stores, we've had two or three a day that have been out of gasoline for part of the day," said Jay Ricker, president of Ricker Oil in Anderson, Ind. Ricker's gas is priced at $3.19 a gallon, after a 70-cent-a-gallon increase at the wholesale level since Tuesday.

But the country's energy-supply chain is designed in a way that puts enormous pressure on Gulf Coast oil producers, refiners and pipeline companies that have been severely limited in the amount of fuel they can deliver to consumers up and down the East Coast.

Bush said during a news conference that until power is fully restored to refiners and pipelines "it's going to be hard to get gasoline to some markets."

While it could be weeks before all eight of the Gulf refineries that shut down are back in action, some key pipelines — owned by Colonial Pipeline and the Plantation Pipe Line — had resumed partial service yesterday. However, analysts said it would take days, if not longer, for the supply constraints to be worked out of the system.

The Energy Department yesterday approved three loans of crude oil from the 700 million-barrel Strategic Petroleum Reserve. The department agreed to provide 6 million barrels of oil to Exxon Mobil, 1 million barrels to Placid Refining and 1.5 million barrels to Valero Energy. Also yesterday, the Bush administration relaxed federal rules to allow foreign oil tankers to transport oil from one U.S. port to another. Industry officials said that would help move supplies to areas that need it.

Seattle Times reporter Tom Boyer contributed to this report.

Material from The Washington Post is included in this report.