Bloomberg — Houston, San Antonio and Dallas, three of the 10 largest US cities, were crippled yesterday by a winter storm that iced central and southern portions of Texas overnight.Schools were closed in Houston, San Antonio, Austin, Fort Worth and the Dallas suburbs after the storm coated roads with ice and snow. Hundreds of flights were delayed or cancelled at airports in Dallas, Houston and Austin, and a 310-mile portion of Interstate-10 was closed last night from Fort Stockton to San Antonio.

"A threat for a mix of frozen precipitation including ice and snow accumulations continues across northern portions of southeast Texas today through Thursday," the National Weather Service's Houston-Galveston forecast office said yesterday.

The system is forecast to bring freezing weather into the US Southeast. Meanwhile, citrus growers in California are calculating the damage from a severe cold snap and thousands of people in the Northeast remain without power while temperatures hover below freezing.

The Associated Press put the nationwide death toll from the past week's storms at 55.

By 3 p.m. local time, snow and rain were easing up across Texas and Louisiana. Forecasters said more was on the way for Texas and New Mexico.

About 90 percent of flights were cancelled this morning at Austin-Bergstrom International Airport after airlines ran out of de-icer because a shipment failed to arrive yesterday, spokesman Jim Holbrook said. AMR Corp.'s American Airlines received a shipment at noon today, he said.

"We will get some planes off the ground, but we won't get them all," Holbrook said in an interview.

Flights at Houston's two main airports were largely back to normal after early morning delays, Houston Airport System spokesman Juan Alanis said in an interview.

Laidlaw International Inc.'s Greyhound Lines Inc. suspended passenger bus service until further notice between Houston and Dallas and San Antonio.

Most of western Texas and central Oklahoma remained under a winter-storm watch yesterday, with an ice storm warning stretching from Houston to Bryan, Texas.

As much as six inches of snow had fallen by 8 a.m. local time yesterday around the Big Bend region of Texas. Austin had as much as 0.4 inch of freezing rain and ice, while Dallas and surrounding regions had about a quarter-inch of sleet.

"As this moisture continues eastward, areas of Georgia and South Carolina could experience some freezing rain during Wednesday night and early Thursday," according to the National Weather Service's Hydrometeorological Prediction Center in Camp Springs, Maryland. "Winter weather and freezing rain advisories have been posted for those areas."

The chill affected a swath of the US from Texas to Maine, killing dozens of people, mainly on the roads, and coating telephone and electricity wires with ice.

In the Midwest, at least 300,000 US homes and businesses remained without power after winter storms that began five days ago downed electricity poles and lines, utilities and state emergency bodies said.

In California and Arizona, record-low temperatures were reported yesterday, when California's State Food and Agriculture Department said 75 percent of its orange crop may be destroyed by the cold snap.

A freeze warning remained in place for parts of California, Arizona and Texas, according to the US National Weather Service website. The service said parts of Maine, New Hampshire, Vermont and New York should expect sub-zero wind-chill today.

US President George W. Bush has declared an emergency in parts of Missouri and Oklahoma, freeing up federal resources. The cold spell has killed nine people so far in Missouri, and at least 14 in Oklahoma, mainly on the roads, the two states' emergency agencies said.

National Grid Plc said that about 13,000 New York state customers were without electricity, and that outages were also affecting some of its clients in Massachusetts. As of 5 a.m. local time yesterday, about 4,300 of Ameren's customers in Illinois were without power, according to the company website.