I have several times referred to one of my favorite blogs "
Briefly, the whole west coast is heating up, with the highest temperatures off the coast in the interiors of Washington and Oregon, with somewhat lower, but still high temperatures, in eastern California and western Nevada (Death Valley could be interesting). Last week (which was wet and cool here) there was a VERY deep low (italicization same as Mass) over the eastern Pacific, and a high-pressure ridge over the Rockies and western Plains. This setup (at the 500 hPa height) allowed moist air to flow in from the southwest. Yesterday (Friday) the low center and the high pressure ridge moved westward, the high-pressure ridge intensified, and the Northwest dried out. By Monday, the high pressure will intensify and will be located west of the Rockies. The low and high regions are getting "squashed" from east to west, aligning the pressure contours in a north-south configuration. Since the winds follow the contours, warm air will flow into the Northwest from the south. This pattern will continue into Tuesday, bringing dry hot air up from the south into the Northwest. The highest temperatures will be east of the Cascades, but they will not be record breaking. To have new records in western Washington, the ridge would have to be further westward than it currently is, essentially sitting on top of Seattle. Mass predicts that on Monday there is a chance of a record high at SeaTac airport; the current high for that date is 87 F.
|CAPE index for Monday and Tuesday|
From the Cliff Mass blog referenced in the text