The deadline for studded tire use is today, March 31st.

The safety of the traveling public is our number one priority, so we encourage drivers to drive for conditions wherever your travels take you. We do expect that snow in the mountain passes will continue for the next few days, and that we may see some brief, wet snow in the lowlands.

Currently, there is no indication of arctic-type weather that could lead to black ice. The presence of this wet snow in the lowlands and occasional heavier snow in the mountains does not indicate reason enough to extend the deadline.

Our weather forecasters also tell us the weather trend looks to be warming statewide, with the upcoming weekend being dry in almost all areas. We have our staff and equipment ready to provide for safe travel, and will impose chain restrictions if necessary.

We often talk about how studded tires damage the roadways. Are you also aware of how studded tires can make driving more dangerous? On wet roadways, you get less traction with studded tires as the studs decrease your stopping ability and increase your stopping distance. This is because they reduce full contact between a tire’s rubber compound and the pavement.

In case you may be traveling, or live outside Washington, you should know out-of-state drivers are not exempt from Washington's laws. The Washington State Patrol will enforce a $124 fine for those who use studded tires after the deadline. State troopers will use common sense if a sudden storm makes roads icy in a particular area.

You can read more about winter driving and tire options at http://www.blogger.com/www.wsdot.wa.gov/winter.

Question of the day:
Why are there two temperatures listed for Stevens Pass? Where are they taken at? I can see 1-2 degree difference in them but sometimes there is 5 or more degrees difference.

Answer:
There are three temperatures displayed on all of the mountain pass pages. The temp in the yellow "Pass Report" box next to the picture of whatever pass you're looking at is what is radioed in to our various Traffic Management Centers from the thermometer on the maintenance supervisor's pickup. That's the air temperature in the shade on the roadside wherever he or she is when they call in the pass report and set the traction restrictions, if any. As a result, the location could vary a mile or more from the summit, depending on the pavement conditions the supervisor has encountered as he/she makes the assessment. That's a call that takes place every 4 hours from November through March. It means that at 1 p.m., you're looking at a temperature that is an hour old. Below the camera image is a blue box labeled "Current Weather". A road weather information station provides that data every few minutes to the web page. The thermometers measure the air temperature and the pavement temperature at the summit of the passes. These are also subject to the influences of any permanent location - sunshine - a bird perching on a sensor or even a vehicle stopped on top of the pavement sensor.

Yesterday, for example, Stevens showed a temperature of 37 for the noon pass report, but by 1 p.m., the current weather box showed an air temperature of 48 and a pavement (surface) temperature of 53. A half hour later, when the sun went back behind the clouds, the temps had dropped to 47 and 51, respectively.

The Blewett pass page showed a similar pattern - 42 degrees in the pass report box and in the current weather box, 52 - air, 42 - surface at 1 p.m.

I checked Snoqualmie, Satus, etc. and Loup Loup (37-37-37) was the only one that showed all three matching, and then only for about fifteen minutes.

You might think we ought to eliminate the temp in the pass report box to eliminate confusion - and we would except that the info in the yellow box is what also appears on several other of our web pages, the 5-1-1 phone system and Highway Advisory Radio's, and NOAA's web site which is what Associated Press uses to provide its member's "news". All of those systems are automated and when conditions do change rapidly, forcing us to change the traction restrictions sooner than the standard "every four hour" schedule, then all of those change, too. It really wouldn't make much sense to update the mountain pass reports every 3 to 10 minutes because the temperature changed a degree or two - and if someone is looking at the pass pages, between the picture, the pass report and the current information, they ought to be able to decide if they want to go or not.