SEATTLE - The latest snowstorm is behind us, but temperatures are expected to dip overnight and thawing roads could freeze over again, making it another icy commute Wednesday morning.

Almost on cue, Tuesday's early morning arctic blast dropped a fresh layer of wet snow on the region between 4 a.m. and 9 a.m., snarling traffic and canceling school for nearly 380,000 students.

One to 2 inches of snow accumulations dropped in the urban areas and 2 to 3 inches fell in the outlying areas.

Storm-weary Washingtonians may be wondering when we're going to thaw out.

"It's going to be a very slow warm up," said KING 5 meteorologist Rich Marriott. "Part of the problem is the ground is so cold right now. It's going to take a while for temperatures to warm up the ground and melt things off. Upper 30s, near 40 degrees doesn't have a whole lot of energy to do that, so it's going to take a while."

Marriott said scattered rain and snow showers would turn to rain showers overnight.

Temperatures warmed slightly during the day, but not enough to melt all the snow and ice on the roads.

National Weather Service forecasters warned that motorists could face treacherous conditions after dark, when the mercury drops below freezing.

"Some of those wet and slushy roadways will refreeze for a slippery commute Wednesday morning," said Marriott.

KING

Snow was falling so heavily in West Seattle, one Metro bus driver told riders to "abandon bus" after the engine significantly overheated.

Marriott said a convergence zone moves in to the region over the next two days, and there's a possibility of another round of wet snow falling Thursday morning. The main roads should be fine for Wednesday's morning commute, but secondary roads that still have frozen ice from two storms ago will pose the most problems.

Latest snow storm snarls morning commute

With ice from the last storm still on many roads, the new snow created treacherous driving conditions.

Interstate 90 was closed between milepost 34 and milepost 40 near North Bend for hours because of several spinout accidents and jackknifed semis.

Pierce County was hammered with the most accidents on Interstate 5 and other major thoroughfares, while West Seattle was another troublesome spot.

In other areas, some slick spots and spinouts were reported, but overall traffic in the Seattle metro area moved slowly and without incident.

Several school districts, including Seattle, Tacoma, and Everett, canceled classes and several others delayed them, affecting some 380,000 students.

KING / Arthur Kuniyuki

Neon signage against a snowy background at Pike Place Market in Seattle.

Transportation crews continued to put de-icer on the roads to ease the pain for drivers.

Lauren Chudecke, a spokeswoman for the state Transportation Department, said plowing, sanding and deicing trucks were working mainly on I-5, I-90 and I-405. Worse than normal backups quickly developed along those and lesser commuting routes.

Local governments have little snow removal equipment and there was still ice on numerous streets in shaded areas from the few inches of snow that fell last week. City crews were concentrating on arterials used by inbound traffic, according to a statement issued by Marybeth Turner, spokeswoman for Seattle Transportation Department.

Latest snow another blow to school calendar

Seattle has lost five days of school and some areas as many as 10, most of which must be made up through reduced spring and midwinter breaks, cancellation of teacher training days and extensions of the school year this summer.

Washington law requires each district to hold at least 180 days of classes in each school year, but state education officials announced plans last week to ease restrictions on waivers from makeup day requirements.

School districts in counties where the governor has declared an emergency will be eligible to apply for an exemption to the 180-day rule, and approval would enable them to make up the lost time in hours rather than days to meet a parallel requirement of 1,000 instructional hours.

Homeowners deal with frozen pipes

With day after day of cold weather, pipes are freezing and breaking, and utility and plumbing companies are slammed with customer calls. From the Eastside to Seattle, many people are now dealing with a whole new problem: frozen pipes. If you're a homeowner, here are some tips to prevent frozen pipes: 

* Drip faucets (running water through the pipe - even at a trickle - helps prevent pipes from freezing because the temperature of the water running through it is above freezing). 

* Open cabinet doors under sinks and closets where pipes are located. 

* Keep doors open between heated and unheated rooms.

Here are some tips if your pipes are already frozen:

* Find the frozen part of the pipe, usually along an exterior wall or where the water enters the house. 

* Wrap pipes with an electric heating pad or use a hairdryer or space heater. 

* Try towels soaked in hot water. 

* Do not use a blowtorch, kerosene or propane heater or charcoal stove. Blowtorches can make water boil and cause pipe to explode.