NOAA's Sunrise/Sunset Calculator - http://www.srrb.noaa.gov/highlights/sunrise/gen.html
Many sunrise/sunset calculators give you the current day's sunrise/sunset, but this site will also give you the sunrise/sunset for any date (1492, 2050) and location.
Northwest Asthma & Allergy Center - http://www.nwasthma.com/resources/pollen.asp
For the allergy sufferer, this site provides reliable pollen counts for Seattle. For counts in other U.S. locations, try the National Allergy Bureau.
Northwest Weather and Avalanche Center - http://www.nwac.us
For the hiker/skier, this site provides current and 10 days' past from several monitoring stations, plus live video cameras from DOT and ski areas. Mountain weather forecasts are also available.
Pacific Northwest Earthquake Information - http://www.geophys.washington.edu/SEIS/PNSN/
This site is from the PNW Seismograph Network at the University of Washington. Reports on latest seismic events, as well as what's happening on the Cascade volcanoes. Includes regional earthquake and fault maps.
Real Time Road & Weather Traveler Information - http://www.wsdot.wa.gov/rweather/
The Washington State Department of Transportation provides weather reports, cameras, pass information and more, on an easy-to-use clickable map. The "I-90 Info" link provides a handy window with weather & road info from Seattle to Ellensburg. WSDOT also provides a traveler page, which includes emergency highway closures and construction reports.
Wind Chill Chart - http://188.8.131.52/om/windchill/
In November 2001, the National Weather Service revised the Wind Chill Temperature Index. This site presents the new chart, plus a wind chill calculator (enter air temp & wind speed to get wind chill.)