Warming Up But How Long Will it Last?

Our anticipated rain pretty much delivered what was expected.  Amounts range from about 0.50" in the Spokane area to around an inch in the northern and eastern mountains.  After some showers on Tuesday, the weather will warm up and dry out.  By Saturday, afternoon temperatures will be in the mid-80s to near 90.  But how long will it last?

As the weather warms, the atmosphere will become more unstable.  Afternoon showers and thunderstorms will become common to our south.  These form over the high terrain of eastern Oregon and southern Idaho, and this is a very common pattern during the summer months.


But then on the weekend, most of the computer forecasts are expecting a weak weather system to move into our area.  When it hits the unstable air over us, showers and thunderstorms will be the result. Saturday will probably be dry, but by Saturday night and Sunday the odds of showers will increase.  Here's the chance of rain for Sunday from the European models.  About a 25-40% chance of showers for much of the area.


The U.S. models are a bit higher on their chances of showers, with a 45-60 percent chance.


It's worth noting that the upcoming weather system is very different from the one we just received in the last 24 hours.  The upcoming system would be hit-and-miss showers.  And there's no guarantee of this weather system.  Strong storms like yesterday's rain tend to have higher confidence.  Weaker weather systems (like the one this weekend) tend to have lower confidence.

After this Sunday/Monday disturbance, high pressure is forecast to rebuild over the area for continued warm weather.  I'll provide another update in a couple of days on the outlook for chances of rain this weekend.


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