A strong dome of hot high pressure over the Inland Northwest pushed afternoon high temperatures into record territory. In late June 2021, a long-lived heatwave broke many daily, monthly, and all time maximum high and low temperature records at several stations.

Excessive Heat in OKANOGAN HIGHLANDS, WASHINGTON
From 26-JUN-21 12:00:00 to 30-JUN-21 23:59:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Republic reached an all time record high temperature of 109 degrees on the afternoon of June 28th. On June 30th, there was a report, from the Washington State Department of Transportation, that there was damage to road surfaces at Sherman Pass due to the heat. Local libraries were arranged to act as cooling centers across the area. There are no known heat related deaths.

Excessive Heat in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 26-JUN-21 12:00:00 to 30-JUN-21 23:59:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Two locations reached an all time record high temperature on the afternoon of June 28th: Plain at 109 degrees and Mazama at 112 degrees. Local broadcast news reported that, near Inspiration Lake, a hiker was rescued after suffering from heat exposure. Local libraries were arranged to act as cooling centers across the area. There are no known heat related deaths.

Excessive Heat in OKANOGAN VALLEY, WASHINGTON
From 26-JUN-21 12:00:00 to 30-JUN-21 23:59:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

From June 26th through 30th, peak temperatures across the Okanogan Valley reached 100 to 117 degrees. Overnight low temperatures cooled to a warm 67 to 73 degrees. Omak reached an all time record high temperature of 117 degrees on the afternoon of June 29th. Local libraries were arranged to act as cooling centers for those with out air conditioning across the area. A report from the Washington Department of Health stated that there were four heat-related deaths in Okanogan County. Further specifics were statewide and not given by counties.

Excessive Heat in WATERVILLE PLATEAU, WASHINGTON
From 26-JUN-21 12:00:00 to 30-JUN-21 23:59:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

From June 26th through July 2nd, the town of Mansfield recorded six consecutive days with a high temperature at 100 degrees or above. Local cooling centers were set up by emergency management for those without air conditioning across the area. A report from the Washington Department of Health stated that there were two heat-related deaths in Douglas County. Further specifics were statewide and not given by counties.

Excessive Heat in NORTHEAST MOUNTAINS, WASHINGTON
From 26-JUN-21 12:00:00 to 30-JUN-21 23:59:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

The town of Northport set a new all-time maximum temperature of 113 degrees on June 28th. Over a five day range, Deer Park Airport afternoon highs reached 100 to 111 degrees and one overnight low only cooled to 74 degrees. There was a report, from the Washington State Department of Transportation, that there was roadway peeling on State Route 20, west of Tiger. There are no known heat related deaths.

Excessive Heat in UPPER COLUMBIA BASIN, WASHINGTON
From 26-JUN-21 12:00:00 to 30-JUN-21 23:59:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: RAWS

Two new all time record high maximum temperatures were set across the upper Columbia Basin on June 28th: Wilbur reached 110 degrees and Odessa 115 degrees. Due to the extreme high temperatures, local libraries for those without air conditioning across the area. There are no known heat related deaths.

Excessive Heat in SPOKANE AREA, WASHINGTON
From 26-JUN-21 12:00:00 to 30-JUN-21 23:59:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

A period of excessive heat left numerous heat-related impacts and new all time record high maximum temperatures in the Spokane Metropolitan area. Spokane International Airport broke their record when they observed an afternoon high of 109 degrees on June 28th. The record warmest low temperature followed on June 30th when only cooling to 78 degrees. Avista Utilities performed two blackouts due to the heat which impacted approximately 8300 customers. There are eight known heat-related deaths in Spokane County. There are no other known specifics about the fatalities.

Excessive Heat in WENATCHEE AREA, WASHINGTON
From 26-JUN-21 12:00:00 to 30-JUN-21 23:59:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

An extended period of excessive heat occurred across the Wenatchee area from June 26th to July 2nd. Afternoon high temperatures ranged from 102 to 114 degrees most afternoons. Overnight lows only fell into the mid-to-upper 70 degrees. There were two all time records set in the Wenatchee area. On the 28th, a new record high maximum temperature was set at Chelan with a high of 111 degrees. On the 30th, Wenatchee's overnight low only dropped to 79 degrees setting a new record high minimum temperature. Numerous cooling centers opened for those without air conditioning during the extreme heat. There are no known heat related deaths.

Excessive Heat in WASHINGTON PALOUSE, WASHINGTON
From 26-JUN-21 12:00:00 to 30-JUN-21 23:59:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Two new all time records were set across the Palouse. The town of Rosalia set a new all-time maximum temperature of 111 degrees on June 28th and Pullman reached 106 degrees on June 29th. There was a report, from the Washington State Department of Transportation, that there was pavement buckling on Highway 195 due to the heat. Due to the extreme high temperatures, Pullman cooling center was established for those without air conditioning across the area. There are no known heat related deaths.

Excessive Heat in MOSES LAKE AREA, WASHINGTON
From 26-JUN-21 12:00:00 to 30-JUN-21 23:59:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

From June 26 to 30th, Moses Lake and Ephrata had high temperatures reach between 103 to 116 degrees, which is abnormally warm for end of June. Ephrata broke their all time high maximum temperature when the airport reached 116 degrees on June 29th. Local libraries were arranged to act as cooling centers for residents without air conditioning. There are no know heat-related deaths.