Rain Chances for Sunday

Our stormy weather is over and the warmer weather started today. This will culminate in temperatures reaching near 90F by Saturday. This is a rather sudden warm up, considering we haven’t had many days in the 80s this spring. But how long will this warmth last?

The computer forecasts continue to show the potential for a weak Pacific storm to move onshore Saturday night or Sunday. When it does so, it will collide with some very unstable air over our area. The result could be showers and thunderstorms. 

The US model is one of the more aggressive models with this scenario, bringing rain to just about all of eastern Washington  


Some computers like the European don’t bring any showers at all. So this is far from a certain rain event.


If the event does happen, the thunderstorms will be of the wet variety. One thing we look at in this kind of situation is the forecast amount of moisture in the atmosphere.  In this event, the atmosphere will be plenty wet. The map below shows over 1” of precipitable water, which is a healthy amount for our area. That doesn’t mean we’ll get a inch of rain though.  But thunderstorm downpours are possible. Also, dew points will be in the 50s so it’s likely to feel a little muggy this weekend.

  

After this potential weekend rain event, high pressure redevelops. This means dry and warm weather with temperatures in the 80s. Dew points will be in the 40s and each afternoon will be breezy, so hay should cure well. The next chance of rain looks to be the following weekend (I.e. around June 15th).  All of the computer ensembles expect a cool low pressure to replace the warm high pressure.  In other words, the warmth next week won’t last.  It’s too far out to predict how much rain we might get from this pattern switch.

Just as an aside, the three rainstorms we’ve had in the last month have brought above normal rainfall to northeast Washington for the past 30 days, but not to most of the Northwest.



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