Excessive heat watch is issued starting Monday

By Terry Murry on Saturday, August 12th, 2023 in Columbia Basin News More Top Stories

PENDLETON – The National Weather Service has issued a widespread excessive heat watch beginning Monday morning and lasting through Thursday evening. Here is the forecast for:

Eastern Columbia River Gorge of Oregon-

Lower Columbia Basin of Oregon-John Day Basin-

Foothills of the Northern Blue Mountains of Oregon-

Foothills of the Southern Blue Mountains of Oregon-

North Central Oregon-Eastern Columbia River Gorge of Washington-

Kittitas Valley-Yakima Valley-Lower Columbia Basin of Washington-

Foothills of the Blue Mountains of Washington-Simcoe Highlands-

Lower Slopes of the Eastern Washington Cascades Crest-

Including the cities of Arlington, The Dalles, Boardman,

Hermiston, Ione, Dayville, John Day, Mitchell, Monument, Spray,

Pendleton, Pilot Rock, Heppner, Condon, Fossil, Dufur, Maupin,

Moro, White Salmon, Ellensburg, Thorp, Naches, Sunnyside,

Toppenish, Yakima, Connell, Prosser, Tri-Cities, Dayton,

Waitsburg, Walla Walla, Goldendale, Bickleton, Appleton,

Cle Elum, and Cliffdell

…EXCESSIVE HEAT WATCH REMAINS IN EFFECT FROM MONDAY MORNING

THROUGH THURSDAY EVENING…

* WHAT…Dangerously hot conditions with high temperatures

exceeding 100 degrees each day (95-100% confidence) and 50-85%

confidence in the hottest temperatures exceeding 105 degrees.

* WHERE…Portions of central, north central and northeast

Oregon and central, south central and southeast Washington.

* WHEN…From Monday morning through Thursday evening.

* IMPACTS…Extreme heat will significantly increase the

potential for heat related illnesses, particularly for those

working or participating in outdoor activities.

* ADDITIONAL DETAILS…Hottest temperatures are forecast Tuesday

afternoon with widespread chances (95-100%) of exceeding 100

degrees for most of the lower elevations of central, north-

central, and northeast Oregon as well as central, south-

central, and southeast Washington. Medium-high confidence

(50-85% chance) exists in the warmest locations exceeding 105 on

Tuesday. Overnight low temperatures Monday night and Tuesday

night are anticipated to be very warm in the upper 60s to

mid-70s for the aforementioned areas. Regarding the warmest

overnight low temperatures, there is a medium-high probability

(50-85% chance) of staying above 75 degrees for climatologically

warm locations such as the eastern Columbia River Gorge and

Columbia Basin of Oregon.

Confidence is still very high (90-100%) in exceeding 100 degrees Wednesday and Thursday, though with a bit more uncertainty in whether temperatures will reach 105 degrees, therefore the lower end of the above range looks reasonable at this time.

(Map: dark red is excessive heat watch. Tan is fire weather watch. Pink is red flag alert. Gray is air quality alert)