2011’s wacky weather

  • Text by the Seattle forecast office of the National Weather Service
  • Friday, January 6, 2012 5:38pm
  • Local NewsLocal news

Depending on which day on the calendar you point to, the weather of 2011 was unseasonably wet, unseasonably dry, unseasonably cool or unseasonably warm. There was an unusual number of low-temperature and precipitation records. At Sea-Tac International Airport, April was the coolest ever. Spring was also one of the wettest on record. And yet we finished the year with less precipitation than normal.

Last year began with one of the strongest La Niñas of the past 60 years in full swing, and 2011 finished with La Niña returning — for only the fifth time in consecutive years since 1950. La Niña years typically bring active winter weather. As if to throw us off, though, there was also relatively tranquil weather last January and again in December.

The year began with a pause in La Niña and relatively mild weather in January. Temperatures were about 1 to 2 degrees above normal. Then La Niña conditions returned in February. Temperatures were between 3 degrees and 5 degrees below normal.

La Niña hung on through the spring, with temperatures well below average and precipitation above normal. Sea-Tac International Airport saw the coldest April ever. And the combined April-May precipitation at the airport was the third-wettest ever.

The wet spring also resulted in one of the latest winter-season flood events at the end of March and in early April. The Snoqualmie River at Carnation recorded major flood stage on April 1, the latest ever.

Many felt we did not have summer, that it was cool and wet. Yet with the exception of the north coast of Washington, June, July, August and September were all below normal for rain. June and July were between about 1 degree to 1.5 degrees below average. August was close to average, and September was quite warm, with average temperatures running between 2 degrees and 3 degrees above normal.

With La Niña returning, temperatures turned cooler in November and December. Precipitation was close to normal for October and November, but there was well-below-normal precipitation in December. In fact, December was of the driest on record. Thanks to the dry December, many locations in Western Washington ended the year with below-normal precipitation.

Highlights and lowlights of 2011

Flooding

Jan. 13-19: A period of rainfall resulted in flooding and a landslide that affected a segment of the Mountain Loop Highway east of Granite Falls. Flooding on the north fork of the Skykomish River washed away a cabin near Index. The Snohomish River reached major flood stage. Other flooding rivers included the Carbon, Cedar, Chehalis from Grand Mound downstream, Green, Newaukum, Nisqually, Nooksack and Puyallup near Orting, Satsop, Skagit, Skokomish, Stillaguamish, Skookumchuck, Snoqualmie and Tolt.

March 30-April 3: More heavy rainfall produced one of the latest winter season flood scenarios on record on the Snoqualmie, Skykomish, Snohomish, Tolt and Stillaguamish.

Nov. 22-24: A period of heavy rainfall of up to 10 inches in the mountains produced the first flood scenario of the fall/winter season. Rivers that exceeded flood stage included the Stillaguamish.

Snow

Feb. 22-23: Snow fell over much of western Washington. Amounts varied from one to 10 inches with Mount Vernon reporting 16 inches.

Landslide

March 10-17: A period of rainfall helped create a landslide that damaged four homes on a slope near Snohomish.

Snowpack

Given the healthy mountain snowpack during the winter of 2010-11 and the cool, wet spring, the snowpack was slow to melt in 2011. Paradise on Mount Rainier on Aug. 15 still had 44 inches of snow — the highest ever on that date.

High winds

Sept. 25-26: Strong southerly winds blew along the coast, the north interior and the Puget Sound region. Winds up to 75 mph were recorded in Whatcom County. Nine thousand households lost power in Snohomish County.

Extreme high pressure

Dec. 1: Sea-Tac Airport recorded the highest atmospheric pressure on record going back to 1948. The barometer hit 1043.4 millibars, or 30.81 inches, of mercury, breaking the previous record set in 1949.

More information about local climate

National Weather Service, Seattle: www.wrh.noaa.gov/sew

Office of the Washington State Climatologist: www.climate.washington.edu

University of Washington Department of Atmospheric Sciences: www.atmos.washington.edu

Talk to us

> Give us your news tips.

> Send us a letter to the editor.

> More Herald contact information.

More in Local News

Trader Joe’s customers walk in and out of the store on Monday, Nov. 20, 2023 in Everett, Washington. (Olivia Vanni / The Herald)
New Trader Joe’s opens this week at Everett Mall

It’s a short move from a longtime location, essentially across the street, where parking was often an adventure.

Ian Bramel-Allen enters a guilty plea to second-degree murder during a plea and sentencing hearing on Wednesday, March 6, 2024, at Snohomish County Superior Court in Everett, Washington. (Ryan Berry / The Herald)
‘Deep remorse’: Man gets 17 years for friend’s fatal stabbing in Edmonds

Ian Bramel-Allen, 44, pleaded guilty Wednesday to second-degree murder for killing Bret Northcutt last year at a WinCo.

Firefighters respond to a small RV and a motorhome fire on Tuesday afternoon in Marysville. (Provided by Snohomish County Fire Distrct 22)
1 injured after RV fire, explosion near Marysville

The cause of the fire in the 11600 block of 81st Avenue NE had not been determined, fire officials said.

Ashton Dedmon appears in court during his sentencing hearing on Tuesday, March 5, 2024, at Snohomish County Superior Court in Everett, Washington. (Ryan Berry / The Herald)
Everett Navy sailor sentenced to 90 days for fatal hit and run

Ashton Dedmon crashed into Joshua Kollman and drove away. Dedmon, a petty officer on the USS Kidd, reported he had a panic attack.

A kindergarten student works on a computer at Emerson Elementary School on Wednesday, Feb. 28, 2024, in Everett, Washington. (Ryan Berry / The Herald)
‘¡Una erupción!’: Dual language programs expanding to 10 local schools

A new bill aims to support 10 new programs each year statewide. In Snohomish County, most follow a 90-10 model of Spanish and English.

Cassie Franklin, Mayor of Everett, delivers the annual state of the city address Thursday morning in the Edward D. Hansen Conference Center in Everett, Washington on March 31, 2022.  (Kevin Clark / The Herald)
At Everett mayor’s keynote speech: $35 entry, Boeing sponsorship

The city won’t make any money from the event, city spokesperson Simone Tarver said. Still, it’s part of a trend making open government advocates wary.

Logo for news use featuring the Tulalip Indian Reservation in Snohomish County, Washington. 220118
Woman drives off cliff, dies on Tulalip Reservation

The woman fell 70 to 80 feet after driving off Priest Point Drive NW on Sunday afternoon.

Everett
Boy, 4, survives fall from Everett fourth-story apartment window

The child was being treated at Seattle Children’s. The city has a limited supply of window stops for low-income residents.

People head out to the water at low tide during an unseasonably warm day on Saturday, March 16, 2024, at Lighthouse Park in Mukilteo, Washington. (Ryan Berry / The Herald)
Everett shatters record high temperature by 11 degrees

On Saturday, it hit 73 degrees, breaking the previous record of 62 set in 2007.

Snohomish County Fire District #4 and Snohomish Regional Fire & Rescue respond to a motor vehicle collision for a car and pole. The driver was pronounced dead at the scene, near Triangle Bait & Tackle in Snohomish. (Snohomish County Sheriff’s Office)
Police: Troopers tried to stop driver before deadly crash in Snohomish

The man, 31, was driving at “a high rate of speed” when he crashed into a traffic light pole and died, investigators said.

Alan Dean, who is accused of the 1993 strangulation murder of 15-year-old Bothell girl Melissa Lee, appears in court during opening statements of his trial on Monday, March 18, 2024, at Snohomish County Superior Court in Everett, Washington. (Ryan Berry / The Herald)
31 years later, trial opens in Bothell teen’s brutal killing

In April 1993, Melissa Lee’s body was found below Edgewater Creek Bridge. It would take 27 years to arrest Alan Dean in her death.

Logo for news use featuring the municipality of Snohomish in Snohomish County, Washington. 220118
Man dies after crashing into pole in Snohomish

Just before 1 a.m., the driver crashed into a traffic light pole at the intersection of 2nd Street and Maple Avenue.

Support local journalism

If you value local news, make a gift now to support the trusted journalism you get in The Daily Herald. Donations processed in this system are not tax deductible.