By Sabina Zawadzki and Edward McAllister
NEW YORK, Jan 24 (Reuters) - A propane shortage is affecting millions of Americans this week as brutal cold exposes the vulnerabilities of a network responsible for heating homes, schools and businesses across wide swathes of the United States.
Prices of the fuel have rocketed to all-time highs in some regions, distributors are rationing supplies, and some schools have shut due to a lack of fuel during this year's second bout of Arctic weather.
The National Propane Gas Association said on Thursday the states of Wisconsin, Minnesota and Missouri are worst hit and that it has heard that some retailers have run out of supplies.
But as record cold coincides with pipeline outages and low inventories, the crisis has spread further. Most households are not connected directly to propane pipelines, and the system relies on truck fleets now running at full capacity to get emergency supplies to states across the Midwest, Northeast and Southeast.
The U.S. Department of Transportation has issued emergency orders suspending the limits on the amount of time truck drivers can spend on the road for 10 Midwestern states and 12 Northeastern states, a rare regional order.
A spokesman for Pennsylvania-based AmeriGas Propane, the largest U.S. propane retailer, said it was rationing deliveries to "small pockets" of Alabama, Georgia and Tennessee on Thursday, reducing supplies to 100 gallons per customer from the standard delivery of some 250 gallons.
"Supply is very tight. There is propane to be had out there, but there are supply and transport issues across the country," spokesman Simon Bowman said.
RATIONING, PRICE SPIKES
U.S. propane production has actually grown thanks to the shale oil and gas boom in recent years, but because of the higher supply, domestic prices sank to below global levels which has encouraged exports of the fuel from the U.S. Gulf Coast to Japan and other Asian countries.
The current shortage in the Midwest comes at a confluence of events. A record-breaking cold snap hit at the start of January when stocks were already low after large amounts of propane was used to dry out a bumper corn harvest in the fall.
A pipeline outage during most of December exacerbated the situation and this week's freezing weather, which is expected to last to the end of the month, has heightened the situation.
All the while prices have soared. Propane heading for the Midwest is priced against supplies in the hub in Conway, Kansas. Prices there touched almost $5 a gallon on Thursday, compared with Friday's pre-freeze price of around $1.75.
Texas has lifted the need for out-of-state trucks to be registered with the state to allow other trucks to come and pick up supplies.
"Long lines have formed at Mont Belvieu," said one Houston-based broker, referring to the largest propane supply hub in the country. "Lots of out-of-state trucks are showing up."
In northern Tennessee, the Stewart County School System opted to close on Thursday and Friday because of warnings from suppliers they were focused on deliveries to residences of up to 150 gallons, said Leta Joiner, assistant schools director.
"We're not sure how long this is going to last," Joiner said. "We decided to err on the side of caution."
One propane supplier in Northern Indiana said customers pleaded for more fuel when he did his rounds on Thursday. Other customers were more hostile, accusing his company of exploiting the shortage to rack up prices.
Few are willing to predict how long this supply squeeze will last.
"We certainly hope that there is a break in the weather," said Roy Willis, president and chief executive officer of the Propane Education and Research Council.
"It could be days or it could be weeks. It really depends on the weather and the logistics of moving the propone."
(Reporting by Sabina Zawadzki, Edward McAllister, Robert Gibbons and Julia Edwards in New York, Tim Ghianni in Nashville; Editing by Lisa Shumaker)