Floods

Ice was melting today as temperatures warmed, but fog and flooding replaced it as new travel dangers.

A dense fog advisory and another for flash floods were issued Friday.

The fog is being blamed on warm air from the south and the melting snow and ice, according to the National Weather Service. The fog warning is in effect till 4 a.m. Saturday.

In addition, the weather service issued a flash flood warning for late Friday through Saturday evening, with a forecast calling for as much as 2 inches of rain.

The rain, combined with melting snow and ice, and mostly frozen ground, could produce flash floods, as well as flooding in rivers and streams.

State police at Pesotum handled four crashes, and had reports of vehicles in ditches this morning, but by afternoon, ice was melting.

There was danger from fog, but no reports of accidents caused by the phenomenon this afternoon, a dispatcher said.

Only one of the crashes resulted in personal injury, and those injuries were not believed to be serious, said Master Sgt. Rory Steidl in a press release.

He said rainfall combined with freezing temperatures to cause black ice, particularly on bridges and overpasses.

Visibility in most places is one-quarter mile or less.

The current temperature is in the low 40s and is forecast by the National Weather Service to rise nearly to 50.

A winter storm continued to sweep across north-eastern US after heavy snow and strong winds disrupted transport, power and schools.

Storm warnings were in place in a dozen states, with the National Weather Service warning of power outages and dangerous travel conditions.

Minnesota could face some of the worst of the blast, with 15 inches of snow forecast, and "impossible" road travel.

It comes after a storm on Friday grounded planes and closed schools.

Among other warnings, the National Weather Service said that in South Dakota there would be a fast-moving Arctic front during the weekend, with bitterly cold winds of up to 40mph (64km/h) creating widespread blizzard conditions.

Extreme weather

The National Weather Service warned New Hampshire residents they could face "greater extremes" on Sunday than they experienced during Friday's blizzard.

Power remained cut to several thousand homes and businesses in New Hampshire after last week's storm.

The forecast said up to 11 inches of wet snow was likely, leading to more power cuts in the state.

The greater danger was the combination of high winds and temperatures falling well below zero.

In the midst of Friday's storm more than 200 flights were cancelled at Chicago's O'Hare International Airport, and more than 650 at three New York City-area airports, with others facing long delays.

In Illinois about 60,000 customers lost power, with a further 35,000 in Ohio and 180,000 in Indiana.

Schools were closed across the north-east region.

In Las Vegas residents and tourists were shocked to see the rare site of palm trees along the Las Vegas strip covered in a thick coating of snow.

More than 3.5 inches (9cm) of snow fell across the city, its heaviest snowfall in nearly 30 years, cancelling flights and closing roads.

Massachusetts Governor Deval Patrick asked non-essential state employees to stay home in a bid to prevent traffic jams on Friday, but New York City Mayor Michael Bloomberg urged people to get out of their houses and go shopping.

In Seattle 11 people were hurt when two buses slid down an icy street, and broke through a guardrail above a motorway.

One dangled for several hours before being towed back from the brink.

MADISON, Wis. -- The past week has been a mix of seasons in Wisconsin, but after a warm weekend, winter's cold has returned.

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Teeth-chattering conditions serve to remind Wisconsin residents of the pluses and minuses of the season once again.

Crossing guard Mary Endres has been working for Madison schools for five years. Although she said she knows from experience to dress warm, others outside might not.

"It's been a bit troubling because we've seen children that aren't dressed for the weather," said Endres.

Being improperly dressed can lead to frostbite, which can have serious implications like infection, amputation and even death. Young children and elderly adults are cautioned to be especially careful as they are more susceptible to cold weather complications.

Health officials said that the best way to be prepared is to stay inside, WISC-TV reported.

"If you do have to go outside, then wearing layers, keeping yourself warm, keeping as much of exposed skin covered as possible is the best thing to do to prevent cold related injuries like frostbite," said Dr. Christian Rickman, an emergency room doctor at St. Mary's Hospital.

Frostbite isn't the emergency room's biggest concern though. The main problem is winter ice.

"Not a shift goes by this time of year where we don't se somebody who has some type of either minor or major trauma from slips and falls. Or their vehicle crashes or other traumatic injuries form ice related problems," said that Rickman.

Madison city officials are trying to prevent such accidents on the streets and sidewalks. They said that the city has the same regulations for property owners as past winters.

"They have to remove ice by noon the day following the accumulation regardless of the source," said Tom Adamowicz, the supervisor of Madison's housing inspections.

Their message is clear: Remove the ice or pay a $109 ticket for the first offence and $172 for the second.

Although ice isn't welcomed on area sidewalks, it is for fishing and at city parks where rinks are being made.

The Madison Parks Division warns that although preparations are underway, no skating rinks are open to the public because of safety concerns. Officials said that they hope the cold weather will help the ice freeze so that some ice will be open this week