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Other Stations in Seattle

About this Station

The Seattle-Tacoma International Airport is located 6 miles south of the Seattle city limits and 14 miles north of Tacoma. It is situated on a low ridge lying between Puget Sound on the west and the Green River valley on the east with terrain sloping moderately to the shores of Puget Sound some 2 miles to the west. The Olympic Mountains, rising sharply from Puget Sound, are about 50 miles to the northwest. Rather steep bluffs border the Green River Valley about 2.5 miles to the east and the foothills of the Cascade Range begin 10 to 15 miles to the east of the airport.

The mild climate of the Pacific Coast is modified by the Cascade Mountains and, to a lesser extent, by the Olympic Mountains. The climate is characterized by mild temperatures, a pronounced though not sharply defined rainy season, and considerable cloudiness, particularly during the winter months. The Cascades are very effective in shielding the Seattle-Tacoma area from the cold, dry continental air during the winter and the hot, dry continental air during the summer months. The extremes of temperature that occur in western Washington are the result of the occasional pressure distributions that force the continental air into the Puget Sound area. But the prevailing southwesterly circulation keeps the average winter daytime temperatures in the 40s and the nighttime readings in the 30s. During the summer, daytime temperatures are usually in the 70s with nighttime lows in the 50s. Extremes of temperatures, both in the winter and summer, are usually of short duration. The dry season is centered around July and early August with July being the driest month of the year. The rainy season extends from October to March with December normally the wettest month, however, precipitation is rather evenly distributed through the winter and early spring months with more than 75 percent of the yearly precipitation falling during the winter wet season. Most of the rainfall in the Seattle area comes from storms common to the middle latitudes. These disturbances are most vigorous during the winter as they move through western Washington. The storm track shifts to the north during the summer and those that reach the State are not the wind and rain producers of the winter months. Local summer afternoon showers and a few thunderstorms occur in the Seattle-Tacoma area but they do not contribute materially to the precipitation. The occurrence of snow in the Seattle-Tacoma area is extremely variable and usually melts before accumulating measurable depths. There are winters on record with only a trace of snow, but at the other extreme, over 21 inches has fallen in a 24-hour period. Usually, winter storms do not produce snow unless the storm moves in such a way to bring cold air out of Canada directly or with only a short over water trajectory.

The highest winds recorded in the Seattle-Tacoma area were associated with strong storms crossing the state from the southwest. Prevailing winds are from the southwest but occasional severe winter storms will produce strong northerly winds. Winds during the summer months are relatively light with occasional land-sea breeze effects creating afternoon northerly winds of 8 to 15 miles an hour. Fog or low clouds that form over the southern Puget Sound area in the late summer, fall, and early winter months, often dominate the weather conditions during the late night and early morning hours with visibilities occasionally lower for a few hours near sunrise. Most of the summer clouds form along the coast and move into the Seattle area from the southwest.

Based on the 1951-1980 period, the average first occurrence of 32 degrees Fahrenheit in the fall is November 11 and the average last occurrence in the spring is March 24.

Data Inventories

Please note that additional data (digital and non-digital) may be available for this station. Contact NCDC if additional details are needed.


Click on the following where available:


• DAT to obtain digital ascii data (charges may apply),
  Please do not order these data if you do not know what a Digital ASCII File is.
  
• INV to view inventory, or
  
• DOC to view documentation

Surface
DAT INV DOC 3200 -Cooperative Summary Of The Day
DAT INV DOC 3210 -Summary Of The Day - First Order
DAT INV DOC SOD -Daily Surface Data (TD3200/3210 combined)
DAT INV DOC 3220 -Summary Of The Month (SOM) Cooperative
DAT INV DOC 3240 -Hourly Precipitation Data
DAT INV DOC 3280 -Surface Airways Hourly And Airways Solar Radiation
DAT INV DOC 3290 -Summary Observation
DAT INV DOC 3292 -Weather Duration
DAT INV DOC 9950 -DATSAV 2 Surface (see Global Surface Station Information).


Upper Air
DAT INV DOC 6301 -
DAT INV DOC 6302 -

DATA

Additional data products may be available for this station. If you can't find what you are looking for here, please try our Most Popular Products page.

Forms, Publications, and Web Pages
Graphs and Other Images
Digital ASCII Files


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Forms, Publications, and Web Pages

Most of these products are publications that have been converted to on-line access. As such, these documents have column headings and are displayed in an easy-to-read format.

For additional information and product samples, click on the icon next to the desired product.

Hourly Precipitation Data for Washington
Daily/Monthly/Annual Washington Climatological Data
Record of Climatological Observations
Annual Climatological Summary
Storm Data Publication


Miscellaneous Storm Events in King County
    *All Drought Dust Storm Flood Fog Hail Hurricane & Tropical Storm Lightning Tornado Wild/Forest Fire Ocean/lake Surf Precipitation Snow & Ice Temperature Extremes Thunderstorm & High Wind

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Graphs and Other Images

Includes contour maps, time series, NEXRAD radar mosaics, and satellite images.

For additional information and product samples, click on the icon next to the desired product.

National Mosaic Reflectivity Images
Miscellaneous Satellite Images


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Digital ASCII Files

These files may or may not contain column headers. In order to use these files, you will need to import them into a spreadsheet or database package for presentation. Please do not order these data if you do not know what a Digital ASCII File is. A sample Digital ASCII File is available for viewing but content varies a great deal depending on your request. Other digital files are available Offline that may contain data for this station.

For additional information and product samples, click on the icon next to the desired product.

SOD -Daily Surface Data (TD3200/3210 combined)
3220 -Summary Of The Month (SOM) Cooperative
3240 -Hourly Precipitation Data

Station History

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