There is a lot of traffic jam in the short strip of I-5 from downtown Seattle north to its city limits during specific timings. The highway starts getting jammed up about 4:30 PM most weekdays.

The express lanes, if you can get on them stay fast-moving until the back-up from the end of them chokes things off, about 4:45 to 5 or so. The jam will last past 6 or 6:30 most weekdays, and it extends well north of the Seattle city limits.

In the mornings, traffic flow is most of the times smooth barring situation in case of some unusual events.

You can get real-time traffic information by visiting the link:

http://www.wsdot.wa.gov/Traffic/seattle/default.htm

Amtrak is also known by the name of National Railroad Passenger Corporation of the United States. It is in fact the only intercity passenger rail service in the US. There are around 500 destinations of Amtrak throughout the United States.

There are mainly three rail routes of Amtrak. These rail routes are Pacific Northwest, Coast Starlight, Cascades and Empire Builder. Of the three, Pacific Northwest is the route that is primarily operational in Seattle.

http://www.amtrak.com/

It is very easy to find information related to the different train schedules by screening the website of Amtrak. All you need to do is mention both to and fro locations and the date of travel needs to be entered and you will get information related to the different rail services.