Newcomer's Handbook Seattle

Weather and Disaster Preparedness

“The bluest skies you’ve ever seen are in Seattle,” sang Perry Como, “and the hills the greenest green…” The late crooner was right. On a sunny summer day, the city is wrapped in aquamarine and the landscape glows green. Such brilliantly lush environs led in part to the city’s nickname of the Emerald City. But Como forgot to mention the rain, and the accompanying mudslides, the frequent windstorms, occasional earthquakes and, every now and then, a drought; such are some of the challenges that Gore-Tex–clad residents contend with every year. In Seattle, jokes about the perpetual precipitation are as constant as the rain. One holds that residents of Seattle don’t tan—they rust. Then there’s the one that asks, “What do you call two straight days of rain in Seattle?” A weekend. The soggiest time in Seattle is November through February, with an average rainfall of nearly 22 inches during those four months. In November 2006 nearly 16 inches of rain fell on the region, dousing the previous record set back in 1933. While waterlogged years like 2006 (when it rained for 27 days in a row, not quite beating the 1953 record of 33 straight days of rain) stand out because they are extraordinary, Seattle is, generally, a soggy city throughout the winter, though stories of nine months of solid rain should be discounted.

When heavy rains do arrive, they are sometimes accompanied by damaging mudslides and floods. The same hills that offer residents spectacular views render homes, trees, and roads vulnerable in extreme weather. In the aftermath of heavy rains and snowstorms residents face mudslides and sinkholes that damage houses and wash out roads, a fact that new residents should keep in mind when searching for a new home. Though mudslides certainly aren’t an everyday occurrence during the rainy months, they happen often enough to cause concern. Geologists recommend that homeowners try to determine if they are at risk for a slide by understanding how water causes damage and what triggers slides. According to experts, steep bluffs and hillsides where earth movement has occurred in the past or where the geology favors such movement are most at risk. That includes the bluffs that encircle Puget Sound and parts of Lake Washington, like West and North Seattle, Magnolia, and Bainbridge Island. With this in mind, folks should search a prospective property for signs of earth movement or signs that the property is getting a lot of water. Indicators include leaning or bent trees, and cracks in the yard, the foundation, driveway or patio. A property that is getting a lot of water may have spots on the lawn that stay greener or that are continually wet, and/or mossy. If you find potential problems, you may want to hire a civil or geo-technical engineer to analyze the drainage situation and make recommendations. Both can be found in the Yellow Pages or by searching online.

Despite its proximity to both the Cascade and Olympic mountain ranges, Seattle is not a snowy city, receiving on average only 8.1 inches per year, though years without any measurable snowfall in the urban areas are common. Communities to the east, like Issaquah, North Bend, and Snoqualmie, get a little more snowfall. Of course, there are exceptions, like the winter of 1999, when record snow levels were recorded in the Northwest and more than 300 inches piled up at the base of the Mount Baker Ski Area. Thing is, it doesn’t take much snow to bring Seattle to a screeching halt. In 2010, a mere 2.5 inches virtually crippled the city, and many people believe the city’s haphazard response to the winter storms of 2008–2009 cost Greg Nickels his third term as mayor.

If you are looking for sun, you may have to drive to find it in abundance. According to the Western Regional Climate Center, Seattle enjoys only 71 days of clear skies a year. In comparison, Yakima, about two and a half hours east of the city, experiences 109 clear days. The WRCC defines a clear day as one that sees zero to 3/10 average cloud cover. The clearest months here are July, with 12 days, August, with 10 days, and September, with nine days. November through February average just three clear days each month. The mixed blessing is that there are also 93 partly cloudy days a year, defined by the WRCC as days with 4/10 to 7/10 cloud cover. Breaks in the clouds can send people racing outdoors to enjoy a couple of hours of sun, regardless of the time of year.

Because sunshine is not a daily occurrence, and weeks can pass without a break in the clouds, about 10% of the region’s residents suffer from Seasonal Affective Disorder (SAD), according to David Avery, a professor of psychiatry and behavioral sciences at the University of Washington. Another 10% experience milder forms of depression. The National Mental Health Association says that as the seasons change, a shift occurs in our internal biological clocks that can cause us to be out of step with our daily schedules. Symptoms include sadness, sluggishness, change in appetite, and excessive sleeping. If you are moving from a sunny state like California or Florida, you should be aware of possible seasonal depression. Many people affected by the disorder have found relief using portable light boxes, like the ones sold by The SunBox Company (

Washington does occasionally experience drought conditions, which in turn set the stage for dangerous wildfires. During drought years, local governments usually ask residents to limit yard watering, and farming communities may impose rolling dry-outs to conserve irrigation water. Wildfires generally are confined to the eastern part of the state, though forested neighborhoods like those in southeast King County also can be at risk. At its website,, the National Fire Protection Association offers tips on protecting your home from wildfire.

Climatologists predict that we’ll see an increase in extreme weather around the world as a result of global warming, and their fears seemed realized when 2010 turned out to be the wettest and hottest year on record. It’s likely that, overall, Seattle will be a wetter and a warmer city in years to come, but it will be more difficult to predict the weather in any given season. In 2011, for instance, the temperature at Sea-Tac airport did not crack 75 degrees until June 23rd—the latest date ever recorded.

Though Seattle’s weather picture can seem bleak, its bane—the rain—is also its blessing. If it weren’t for the rain the hills wouldn’t grow nearly as green and the deep blue skies wouldn’t be so revered.

Weather Statistics

Despite the clouds, a reputation for rain and occasional extreme weather, Seattle has a mild, temperate climate, receiving 38.06 average inches of rain in a year, far less than some other areas of the country. According to the Western Regional Climate Center (, the average minimum and maximum temperatures at Sea-Tac Airport are as follows: January 37–46° F; February 37–49° F; March 40–52° F; April 42–58° F; May 48–64° F; June 52–69° F; July 56–76° F; August 56–76° F; September 52–70° F; October 46–59° F; November 40–51° F; December 36–46° F.

Air Pollution

Gazing out at the Sound on a crystal-clear, rain-washed afternoon, it might be hard to believe that Seattle has an air pollution problem. However, the American Lung Association’s 2011 air quality report ranked the city the 18th most polluted in the country for fine particles such as soot. In winter, particles associated with smoke from wood stoves and fireplaces build up. In summer, the region’s traffic congestion, and the emissions from gas engines on boats, jet skis, and lawnmowers creates smog or ozone problems. High ozone levels place Seattle 180th of 220 metro areas for this public health hazard. To help combat the problem, vehicle emission tests are required every other year in King, Pierce, and Snohomish counties. Recent programs to scrap or retrofit the exhausts on older diesel trucks and to reduce school bus emissions are among the efforts to improve air quality in the region. In 2011, the city pledged to become a climate-neutral city, setting the goal of reaching zero net greenhouse gas emissions per capita by 2030.

The Puget Sound Clean Air Agency, which is charged with enforcing federal, state, and local air quality laws, provides current air quality reports and forecasts at its website, You can also view images from its Seattle visibility camera and receive information about local burn bans. The agency recommends the following tips for improving air quality:

  • Use an efficient EPA-certified pellet or wood stove. Uncertified wood stoves are illegal to use during a burn ban.
  • Burn manufactured logs or pellets.
  • Dry firewood at least six months before using it.
  • Give your fire lots of air for optimum heat and minimum smoke.
  • Drive less. Take public transportation, bike, or walk whenever possible.
  • When the weather is hot, refuel your vehicle during cooler evening hours.
  • Make sure your gas cap seals properly.
  • Wait until temperatures decrease and breezes pick up before mowing the lawn or using gas-powered garden equipment.
  • Consider using non–gasoline-powered equipment, like a sailboat instead of a motorboat or a manual push mower instead of a gas-powered lawn mower.

Disaster Preparedness

A federal study released in 2000 found that Washington is the nation’s second-most-vulnerable state to costly damage from earthquakes. Seattle ranks seventh in the nation among major cities that could expect severe quake damage. Knowing this, it was nonetheless shocking when the 6.8-magnitude Nisqually Earthquake struck the Puget Sound region on February 28, 2001. It was the biggest quake to rattle the area in more than half a century. It caused 410 injuries, and damage statewide was estimated at $2 billion. Experts agree that Seattle was lucky. The quake was buried 32 miles deep, so its effects were muted. Experts also agree that the Nisqually Earthquake was not the “Big One” that the region can expect. The Seattle Fault Line, which runs east-west through the heart of downtown Seattle, Bellevue, and Bainbridge Island, is a shallow fault that would cause severe damage if it’s the cause of the next big earthquake. Such a seismic event is overdue, but experts can’t predict if it will happen tomorrow or a hundred years from now. Seattle’s tsunami risk has not been fully studied, but most tsunamis damage open coastlines and not enclosed bodies of water such as Puget Sound.

Aside from luck, the secret to surviving a major earthquake, or any other major disaster, is found in the time-proven Boy Scout adage, “Be prepared.” There are dozens of good books about how to get ready for a seismic onslaught, and plenty of free information available from local, state, and federal agencies. You should prepare to be on your own for three to seven days, as it may take that long for emergency crews to restore power, water, and telephone service to affected areas.

The King County Office of Emergency Management maintains a 3 Days 3 Ways website ( that provides links to disaster preparedness resources and recommends a simple three-step approach to any disaster: make a plan; build a kit; get involved. You can get in-depth information about local hazards, learn how to develop communication and evacuation plans and what kind of supplies to keep in a disaster kit. The basic rule of thumb is to keep enough water and food on hand to supply your family for three days. For a major disaster, however, supplies for seven days are strongly urged. You’ll want supplies like flashlights, a battery-operated radio, and a first aid kit as well. Don’t forget about medications and providing for your pets.

The Red Cross of Seattle King County ( also offers plans and resources for disaster preparation. Both sites urge people to get training in CPR and basic first aid, and outline ways to get involved with helping your neighbors and community. The City of Seattle sponsors SNAP (Seattle Neighborhoods Actively Prepare), a program in which the city trains groups of local people to respond to the needs of their neighbors and coordinate with officials during a crisis. To get more information or to find a SNAP group near you, call 206-233-5076 or visit

Here are a few additional resources for disaster preparedness:

One final note: be sure to purchase a homeowner’s insurance policy that covers quake damage. Generally, earthquake coverage is not part of a standard policy. See Finding a Place to Live for a list of area insurers.

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