Cool Weather Ahead

Our expected windy days have arrived, ushering in a rather cool low pressure system into the Northwest this weekend.  Daytime temperatures will be in the 60s, with overnight lows dropping into the mid-30s Sunday morning and possibly Monday morning.

By Monday, here's what the weather map will look like.  Cold low pressure in the West, hot high pressure in the East.  This is pretty much the opposite of what we normally see in the summer.


The cool weather in the West won't make any news headlines, except for some snow in Montana and the high mountains.  But the news will be all over the heat back East.  Below is a map of forecast high temperatures for next Wednesday that will approach or break daily record highs.  Of course, it will be rather humid as well, with nighttime low temperatures in the 70s.



For our area, we'll see showers this weekend, mainly on Saturday.  Here's the European model forecast for Saturday and Saturday evening.  These are going to be showers, so don't get hung up on the exact details of placement and amounts.


This time the US GFS model is the drier forecast.


As I said, Sunday will only see a few showers after a chilly morning.  Then our attention turns to Monday and Tuesday.  As I mentioned in our previous blog, the vast majority of the computer forecasts expect just showers for the first part of next week.  But there continue to be a few forecasts that want to give us a rainy day on Monday.  With the low moving by to our south, this pattern will definitely bring widespread rain to Montana, and some of that rain could spread west into our area.  

Once again, here's the plume diagram for accumulated rainfall from the 30 US models.  As with the previous blog, most of the models bring about 0.25" of rain for the next 10 days, but a few of the forecasts give us a lot more.


Looking further ahead, the overall weather pattern weakens, but doesn't dramatically shift.  The warm weather persists in the East while near-normal temperatures (i.e. around 80F) return to our area.  Dew points will be back in the 40s so we should see dew each morning next week.


Precipitation chances after Tuesday look very low, with the next chance of rain waiting until next weekend.




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