Pacific Northwest Been the Country's Most Extreme Weather Region in 2017

Brian Donegan
Published: August 2,2017
When it comes to extreme weather, the Pacific Northwest has seen a little bit of everything so far in 2017.
This includes a cold and snowy start to the year followed by a dry summer with some of the hottest temperatures ever recorded.
Here's a closer look at each season.

A Cold, Snowy Winter

The first three weeks of January featured four separate winter storms in parts of the Pacific Northwest: Helena, Iras, Jupiter and Kori.

Tree branches, broken from the weight of heavy snow, are scattered on the ground of the park blocks across from the Portland Art Museum in Portland, Oregon, Wednesday, Jan. 11, 2017.
(AP Photo/Don Ryan)

Iras, Jupiter and Kori all dumped accumulating snow or ice in Portland, Oregon. Winter Storm Jupiter was an unexpectedly crippling snowstorm for Portland, with up to 15.5 inches reported in parts of the metro area. The city's heaviest snowstorm since February 1995, Jupiter led to abandoned vehicles on snow-choked roads.
After 8 inches of snow from Winter Storm Jupiter at the National Weather Service (NWS) office in Portland, at least 1 inch of snow remained on the ground from Jan. 10 through Jan. 17, a streak of eight straight days.
While you wouldn't bat an eye about this streak in, say, Minneapolis or Caribou, Maine, NOAA's ACIS database said there were only six longer streaks of at least 1 inch of snow on the ground at Portland International Airport or the NWS office, where official data is now taken, dating to 1940.

1. 29 days (Jan. 13 - Feb. 10, 1950)
2. 20 days (Jan. 20 - Feb. 8, 1949)
3. 13 days (Jan. 20 - Feb. 1, 1943)
4. 12 days (Jan. 27 - Feb. 7, 1956)
5. 10 days (Dec. 29, 1968 - Jan. 7, 1969)
6. 9 days (Dec. 19-27, 2008)

Portland averages just two days each winter with at least 1 inch of snow cover.
Winter Storm Helena just missed Portland, but dumped 20 inches of snow near Bend, Oregon, and led to some relatively rare snow along the southern Oregon coast.
Given the number of winter storms, it's no surprise the winter was much colder than usual for the somewhat maritime climate of the Pacific Northwest.
In Portland, all but one January day was colder than average, and only 1979 had a colder Jan. 1-16 period, according to the Southeast Regional Climate Center. The month finished as the seventh-coldest on record.
Seattle also saw a cold January, with 22 of the 31 days below average.
Then, in February, Winter Storm Maya dumped the heaviest snow on the Seattle metro area in five years. Sea-Tac Airport picked up 7.1 inches of snow from Maya Feb. 5-6, 2017, making it the heaviest two-day snowstorm since Jan. 18-19, 2012.
The storm reportedly knocked out power to tens of thousands of Puget Sound Energy customers early Feb. 6, according to KIRO-TV.
Officially, only a trace of snow was measured at the NWS office in Portland from Maya. However, parts of Oregon's coastal range picked up a foot of snow, and the Oregon coast picked up a rare significant snowfall.
Portland ended up experiencing its fifth-coldest winter on record, with an average temperature of only 37 degrees. This is equivalent to its average low in late February.
In Seattle, it was the coldest winter since 1985, and a total of 56 days featured below-average temperatures from December through February.
(MORE: Where Winter Ranked as One of the Warmest, Coldest, Wettest or Driest on Record)

Cloudy, Rainy Spring

The Pacific Northwest may have a rainy, dreary reputation, but the persistence and amount of clouds and rain this year have rewritten the record books in both Seattle and Portland.

A rainy day in Seattle.
(AP Photo)

As of July 31, both cities are experiencing their second-wettest years to date, according to the Southeast Regional Climate Center.
Portland has received 29.26 inches of precipitation (rain and melted snow) since Jan. 1, over 9 inches above average by this point in the year.
Sea-Tac Airport in Seattle has recorded 28.40 inches of precipitation so far in 2017, nearly 9 inches above average through July 31.
(MORE: Sunless in Seattle: New Records Smashed For Rainy-Season Precipitation)
If that isn't depressing enough, Sea-Tac managed a total of five sunny days – defined as a daily average sky cover of 30 percent or less – from Jan. 1 through April 30. Four of those days occurred in January and the other in February, the day before Valentine's Day.
Yes, that means there were no sunny days in March or April. Conditions improved in May when five sunny days were recorded.
There were periods of sunshine here and there, despite this meager sunny-day statistic. But the gloomy stretch challenged the patience of even long-time residents – or stoked a good sense of humor, at least.
A mid-March sun sighting elicited a highly retweeted post from NWS-Seattle.
One month later, a NWS meteorologist in Seattle wrote a short poem in a forecast discussion in hopes of breaking the cloudy curse. Dr. Cliff Mass humorously referred to western Washington as a "sunless disaster area" in an April 23 blog post.
(MORE: America's Dreariest Cities)
But then the tables turned as spring transitioned to summer.

Abnormally Dry Conditions

Wet days are not a common occurrence in Seattle during July since it's typically the driest month of the year.
The dryness in July 2017, however, has entered the record books. No measurable rain was observed at Sea-Tac Airport through the entire month.
Seattle has had only 10 other months without measurable precipitation in records dating to 1894, most recently in July 2013 and August 2012.
(MORE: Seattle's Rainy Reputation is Well-Deserved)
Additionally, as of July 31, Seattle is in the midst of its fourth-longest dry streak on record at 44 days, last seeing rain on June 17 – but this comes with a bit of an asterisk.
Many Seattleites saw drizzle July 27, but these tiny raindrops only accumulated to a trace of rainfall. This is not considered measurable rainfall, which means that Sea-Tac – the official measurement site for Seattle – continues its dry streak.
This prolonged dry stretch has led to the development of "abnormally dry" conditions on the U.S. Drought Monitor analysis. As of July 25, 18 percent of Washington and 34 percent of Oregon was classified as abnormally dry.

Summer Heat Wave Threatens All-Time Record Highs

A blistering heat wave will sear the West Coast this week, threatening some all-time record highs in parts of Oregon and Washington, pushing Seattle toward a rare triple-digit high.
(MORE: Western Heat Wave May Near All-Time Record Highs in Oregon and Washington)
The NWS office in Portland warned this upcoming heat wave could be the city's strongest in eight years.
The peak of the heat wave will likely be Wednesday and Thursday, with highs in the 100s commonplace from California's Central Valley and western Nevada into Oregon and much of Washington's lower elevations away from the immediate Pacific coast. Some of the hottest interior locations may even flirt with 110-degree highs.
(MORE: Hottest Temperatures Recorded in All 50 States)
Roughly a handful of cities will flirt with their all-time record highs.

Forecast Highs

In records dating to 1894, Seattle has only had three days of 100-plus-degree heat, all in July:

• July 29, 2009: 103 degrees
• July 20, 1994: 100 degrees
• July 16, 1941: 100 degrees

Seattle could flirt with that rare century mark late this week. The dry ground, courtesy of the dry streak detailed above, will contribute to the heat wave in the Emerald City.
(MORE: How Often Your City Reaches 100 Degrees)
In Portland, this may be only the eighth heat wave in 77 years featuring at least three consecutive days of triple-digit highs. There's a chance that Portland could see four days in a row with triple-digit heat this week, and that would be a first since August 1981.
Brian Donegan is a digital meteorologist at weather.com. Follow him on Facebook and Twitter.
MORE: Winter Storm Maya, February 2017