Hot Summer Days

 As we near the climatologically hottest weeks of the year (last week in July and first week in August), it appears that the atmosphere is pretty much sticking close to the script.  We've had some hot spells already, and those look to increase.

First, we're looking at a hot weekend.  Strong high pressure centered over California has built a ridge over the western states and into BC.  But a low is lurking off the coast with another low over Alaska.


The Alaska low will drop southward into the Gulf of Alaska.  This will kick the current Gulf of Alaska low inland, moving through our area on late Sunday and Monday.  This will be a dry weather system with maybe a few showers near the BC border.  But the main weather with this low will be wind.  Sunday will be hot with a few gusts in the late afternoon.  The wind aloft will increase Sunday night.  This will keep our overnight temperatures warmer.  Dew will probably only form in a very localized sheltered valley.


Winds will increase on Monday with gusts to 35 mph across much of eastern Washington.  Temperatures will drop back into the 80s with the dry cold front passage.  High fire danger for Monday.  Winds will decrease Monday night, but probably not enough to allow widespread dew to form.


Following this, the high pressure ridge rebuilds for warmer temperatures by the end of the week.


By next Saturday, the high pressure is still over the western US.  The deep low off the coast has inched closer, but doesn't appear to have any plans to move onshore.  But there's an important point worth noting.  The axis of the ridge of high pressure (thick black line) is to the east of the Inland NW, over Montana.  This means that we will continue to be "open" to possible cooler air moving in from the west.  If this axis was directly overhead or slightly to our west, the door to the Pacific would be "closed" and we would have nothing but heat.


Looking even further into the future (last week of July), the pattern looks similar.  The 4-corners high looks really strong at this point, which is normal for this time of year.  But again, the ridge axis is over Montana, not Washington.  So there is still hope that while this will be a hot weather pattern, there could be occasional breaks of cooler weather, similar to what we have coming for this Monday.

One positive aspect of this pattern is that the wildfire smoke from northern British Columbia will hopefully stay east of our area.  Here's the current smoke forecast.  The smoke streaming down from Canada should remain east of the Continental Divide for the most part.  


Current air quality sensors confirm the smoke model forecast.


This morning's satellite also confirms a thick plume of smoke to our east.









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