Summer Rain update

 
I wanted to provide a quick update to our upcoming rain event.  Now that we're within 48 hours, there are computer forecast models that show a depiction of what they think the radar will look like.   Again, these are just computer forecasts, not necessarily reality.

Below is one model's expectation of the rain event.  There are others that are wetter, and others that are drier.  I chose this one as somewhat a middle-of-the-road.  The main things to take away from this are:

  • There will be multiple impulses of rain moving into eastern Washington from the east.
  • Each impulse looks like it will be a bit farther north than its predecessor.
  • Spokane and points north could see a light sprinkle Saturday morning, but the heavier showers in northeast WA will be more likely starting in the late afternoon.
  • There will be multiple impulses moving through the area Saturday night.



The actual amount of rain is still very difficult to forecast.  Here's the average of 5 high-resolution computer models.  You can see that some areas get less than 0.1" of rain, while others get over half an inch.



It still looks like that second storm from the west will bring more rain to us on Monday.  So here's a few rainfall forecasts for both events combined.

First, the European model.  This paints a widespread 1 to 2 inches of rain north of highway 2.



The Canadian model has almost the opposite idea.  It forecasts the heaviest rain to be south of Highway 2.


Lastly, the U.S. model is probably somewhere in between the Euros and Canucks.



And here's the timeline for the rain events at Deer Park.  The top graph shows that the chances of rain start off small Saturday morning, but then ramp up considerably by about 6pm and stay high through Monday afternoon.  It's not going to rain for 48 hours straight, but expect off-and-on showers through that period.  

The bottom graph shows the amount of rainfall.  The combination of the 2 systems is forecast to give Deer Park about 3/4".



Also, daytime temperatures will be rather cool, mainly due to all of the cloud cover.  We've probably seen the last of the 90s for more than a week, and odds are that a few days won't even reach 80F.  But we also won't be dropping into the 40s overnight, thanks to the blanket of clouds.  Dew points are going to approach 60, so it might feel a little muggy.


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