Will the cool pattern to continue? Only 3 days has the average temperature in Seattle been at least 2 degrees above normal. Also during this period the average temperature departure from normal has been 1.2 degrees (F) below normal. Why? The map below is a 500 mb chart (at about 18,000 to 19,000 foot level) and this has a trough of low pressure just to our north and this is for the date July 28. This has been the weather theme for much of the summer as a trough of low pressure has been anchored over the Northwest and this usually brings below normal temperatures and above normal precipitation.
The standard joke use to be summer in Seattle begins July 5 well this year it was 84 on July 6 so maybe summer ended on July 6.