No Measurable Rain Since May, Some in Northwest Nearing Record Dry Streaks

Jon Erdman
Published: August 25,2015

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In what is perhaps the most jarring statistic of the severe-to-extreme Northwest drought, some locations in Washington and Oregon haven't picked up any measurable rainfall since May.

Locations Without Measurable Rain Since May

According to the National Weather Service office in Pendleton, Oregon, three cities in southeast Washington and northern Oregon have not seen measurable rain -- at least 0.01 inch -- since mid to late May.

• The Dalles, Oregon: May 12
• Kennewick, Washington: May 23
• Pasco, Washington: May 27

This is a record such dry streak -- 88 straight days -- for Pasco, Washington, dating to 1948 and nearing the all-time record streak in The Dallas, Oregon -- 108 straight days ending June 26, 2012. As it happened, a stray thundershower ended the record streak late Monday night in Pasco, dumping a whopping 0.03 inch of rain.
Summer is typically the driest time of the year in the interior Northwest, with June through August average rainfall only in the range of 0.75 to 1 inch. However, a complete lack of any June through August measurable rain in these areas is very rare.
Since 1948, this has only happened once before in The Dalles, Oregon (2003), located in the Columbia Gorge about 85 miles driving distance east of Portland.
In Kennewick, Washington, examining years with complete monthly records, there is no record of this occurring dating to 1894, though several summers (1949: 0.01 inch; 1919: 0.03 inch; 1906: 0.02 inch) came close.
Even two of the driest locations in the United States, Death Valley, California (0.25 inch), and Yuma, Arizona (0.42 inch), have been wetter than The Dalles, Kennewick and Pasco since June 1.

Current Drought Monitor Analysis

It stands to reason, then, the drought has worsened quickly in the Northwest since spring.
Furthermore, Washington state has for the second summer in a row witnessed the largest wildfire in state history.
Due to tinder box conditions, episodes of strong winds and thunderstorms producing little rain but ample lightning, roughly 50 large wildfires are burning in the Northwest as of August 25.
(IMAGES: Air Quality Worse Than Beijing)
Is there any hope ahead?
While the heart of the Northwest's rainy season doesn't kick in until November, there is a welcomed pattern change on the way.
(FORECAST: The Dalles, Oregon | Kennewick, Washington)
Not only could this bring the first summer rain to these parched cities, but it will also help remove the stagnant, smoky air that has settled into parts of the Northwest and also bring cooler temperatures.
It's not all good news. Strong, gusty winds ahead of the front may fan existing wildfires, and hit-or-miss mainly dry thunderstorms ahead of the cold front may lead to more lightning-ignited fires.
Unfortunately, the fall does not provide a lot of drought relief hope. The strengthening El Nino is expected to keep the Northwest drier than average through November, according to NOAA's Climate Prediction Center, and possibly through the winter and spring wet season ahead.

MORE: Western Wildfire Photos (August 2015)