The warm (hot) conditions in our region during the last several weeks are over for now. Seattle tied a record for the most consecutive days over 85 degrees, 9 days. That should end today, Tuesday July 31. The reason for the warm conditions was a strong upper level ridge of high pressure that was anchored over our region. This ridge will shift to the east today and be replaced by a trough of low pressure that forms off our coast.
With this trough, temperatures will cool and bring a chance of showers at times mainly for the mountains Thursday and Friday but some drizzle for Seattle as well.
We now are asked whether this is the end of summer in the Northwest? Models disagree! The European model (see map below) indicates a trough of low pressure for this Monday and if this verifies this would continue the cool temperatures and chances of rain early next week. However the US models show the ridge of high pressure rebuilding on Monday (8-6-2018) for a return to dry and warm conditions. Stay tuned!! My best guess is the ridge of high pressure will rebuild and thus lean to the US models.
|500 mb (18,000') for Monday August 6, 2018|