But history is not destiny and it appears August will be far cooler.
Let's start by looking at the latest forecast by weather.com for the first two weeks of the month (see below). Most of the days only get into the mid-70s: about as average as you can get.
The NOAA 6-10 day forecast concurs, with close to normal temps over our region/
The 6-10 day precipitation forecast is for ABOVE-NORMAL precipitation over our region (see below)
What about the next week? Here is the total precipitation forecast over the next 7 days from the National Weather Service GFS model: the Northwest gets some modest rain and only southern CA and Texas are dry.
Why the change?
The persistent high pressure (ridging) over the western U.S. has been replaced by troughing (low pressure). Here are the ensemble (many model) forecasts of the difference of the upper level (500 hPa) heights from normal (the anomaly). Blue indicates below normal heights, while higher than normal height (pressure) by green and reds.
The 72h shows several troughs over our region.
At 168 hr (next Monday) there is a trough right over us.
Bottom line: no heat wave the first half of the month, as the atmosphere stays in a very different configuration. Thus, there is little chance that August will be a record warm month over the Northwest.
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