And strangely, they have cooled while the rest of us have warmed and will warm as the weather cools over the interior this week. Weird weather here in the Northwest!
Consider the temperatures at Newport, Oregon, on the central Oregon coast (station NWP03, see map below). Temperatures had fallen there over the past 10 days to highs of 50-52F, but started warming a bit (to a torrid 55F) yesterday. I might note that while the 50s were observed along the coast, 90s were only a short drive away to the east in the Willamette Valley!
During that period it was not only cold, but windy at Newport and other coastal locations, with winds increasing to over 24 kts! The wind chill temperature is down in the mid 40s. Feels like winter in summer!
A hint of what is going on is found from the latest sea surface temperature chart (see below, in °C, purple is very cold, blue is cold, then warming with green, yellow to red). The coastal Pacific is really cold--at 11 C (about 51F) and cooler. At some locations the coastal Pacific has dropped to around 47F!
Strangely enough the cooling is directly associated with our nice weather in the interior. The warming interior caused pressure to fall relative to the high pressure over the ocean (the East Pacific High). The resulting pressure differences produced day after day of strong northerlies along the coast (thus the origin of the powerful winds). The following forecast of sea level pressure and winds from the UW WRF model for a few days ago illustrates this.
Strong northerly winds cause upwelling of cool water from below...but this only happens near the coast....thus the area of cold, coastal water. (see explanation of upwelling here)
But as the interior cools and an upper trough moves in during the next few days, the winds should relax along the coast and the upwelling should weaken. So strangely, it will warm at Newport and other coastal locations.
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