Hottest Temperatures on Record for This Early in the Season Possible in Pacific Northwest (FORECAST)

June 7,2015




 

If you live in the Pacific Northwest, we hope your air conditioner is running – if you have one in the first place – because hot conditions have arrived throughout the region.

Current Heat Alerts

Record heat is on tap for much of the Pacific Northwest and will persist into early this week. High temperatures will generally be 10 to 25 degrees warmer than usual for this time of year. In some cases, it may be the hottest weather ever recorded this early in the year.
Such high temperatures can become dangerous for those exposed to the elements for lengthy amounts of time, as heat exhaustion and dehydration may set in. Be sure to drink plenty of water, and schedule plenty of rest in cool, dry areas.
The National Weather Service has issued a heat advisory for the Willamette Valley in Oregon, including Portland and Eugene. A heat advisory has also been issued for inland locations of the Bay Area in California on Monday.

Forecast Highlights

Forecast Highs

Forecast Highs

Yakima, Washington, may see its highest temperatures on record for so early in the season and will flirt with the all-time June high of 105 degrees set on June 23, 1992.
The average high for Yakima, Washington for the first week of June is 78 degrees. Contrast that to the 96 degree high recorded there on Saturday.
On Sunday, Yakima smashed the former record of 96 degrees (set in 1977) when the thermometer broke the century mark and hit 101. The triple-digit heat is expected to continue into Tuesday. Prior to Sunday, Yakima had never recorded a temperature of 103 or higher before June 16 since records began in 1946.
(MAPS: 10-day Forecast)
Most areas in Washington and Oregon, however, will not see temperatures over 100 degrees. Those readings will likely be confined to the Lower Columbia Basin and parts of the Yakima Valley, as well as the Rogue Valley of southwest Oregon.
Parts of the Sacramento Valley of northern California could also soar into the 100s in the days to come. Some locations that are expected to tie or break daily high temperature records include:

• Pendleton, Oregon: Forecast to hit the upper 90s on Monday (record: 98 degrees).
• Redding, California: Thermometers hit 102 degrees on Saturday and 105 degrees on Sunday. Redding is forecast to hit 100+ degrees through Tuesday, though a record high of 111 Monday (set in 2013) will be very tough to beat. The current record high of 104 Tuesday, however, may be broken.
• Spokane, Washington: After a high of 91 degrees on Sunday, thermometers are expected to continue the trend of reaching the low to mid 90s on Monday (record: 91 degrees) and Tuesday (record: 93).

The heat will shift east into Monday and will stretch from the Northwest coast across Idaho, Montana and into the Dakotas. A few daily record highs may fall in Idaho and Montana as well.
(MORE: Record Heat in March for Parts of the West)

Monday's Highs and Departure From Average

Glacier National Park will see temperatures climb to near 90 degrees, which will threaten daily record highs on Monday (89 degrees).
Missoula, Montana will also be in reach of current records on Monday (91 degrees) and Tuesday (90 degrees).
Boise, Idaho will see temperatures surge into the mid-90s, possibly breaking the record high on Monday of 96 degrees set in 1890, as well as the current record of 98 degrees on Tuesday.
Seattle and Portland, Oregon will also see temperatures warmer than expected for this time of year. Highs in Seattle will climb into the 80s, with Portland likely reaching the low 90s or upper 80s. The average high in Seattle for early June is in the upper 60s,  and Portland usually sees highs in the lower 70s. This warm spell comes after the warmest winter on record in both Seattle and Portland.
(MORE: Warmest Winter on Record)
One other interesting tidbit regarding this heat: Temperatures in mid-levels of the atmosphere will flirt with the warmest readings ever seen during the first half of June and may even near all-time records for the month, according to the National Weather Service in Spokane.

What is Causing the Record Heat and How Long Will It Last?

So what is the culprit for this potentially record-breaking heat?
A strong upper-level ridge has built in from the Pacific, covering much of the Northwest since Saturday and will last until early week. This ridge of high pressure will lead to drier and much warmer conditions.
As this area of high pressure begins to slowly slide east, the core of the heat will move east as well.
(MAPS: Weekly Planner)
The good news is that cooler air gradually returns by midweek.
A shortwave trough will pass through western Canada, which will push a weak, but dry cold front through the region. Meanwhile, weak troughing is expected to develop off the West coast. This will lead to a gradual cooling trend. However, temperatures will still likely remain above average through the week.
This subtle pattern change may also draw some moisture back northward and result in a slight chance of showers or thunderstorms midweek.
MORE: Dozens Hospitalized During L.A. Marathon Due to Record Heat