When does the rain return?

 After a rather showery week prior to the Memorial Day weekend, the weather pattern has definitely shifted.  Dry air from the west has pushed the humid air out of our area, leaving us with cooler temperatures and much lower dew points.  This allowed our low temperatures to drop into the 30s in some locations, including a 35F reading at Springdale.

This weather pattern is great for 1st cutting.  The low dew points mean low humidity, along with sunshine and breezy afternoons.  The ground is still pretty wet so it may take a little extra drying time.  But how long will this last?

The image below shows atmospheric moisture anomaly.  Green/blue colors indicate more moisture than normal, brown is for drier than normal.  You can see how dry air pushed into Washington and Oregon, but there's higher moisture to our south and east.  This pattern will continue through the weekend.  Temperatures meanwhile will start to warm, into the 80s by this weekend and sticking around all next week, possibly reaching the lower 90s.



The atmospheric moisture pattern will change next week.  By Tuesday, our dew points will be going up and moisture will be increasing over our area.


By next Thursday, our atmosphere will have a lot more moisture.  Say good bye to those low dew points and humidities (along with the chilly mornings).  


The warmer temperatures coupled with the higher moisture will bring the threat of thunderstorms back into the forecast next week.  At first, the odds are pretty low.  Here's the probability of 0.01" of rain from the GFS ensemble for Tuesday.  You can see only about a 16% chance of rain for the Inland NW.


By next Thursday, the GEFS model is giving our area a 60% chance of rain.  The European model (not shown) agrees with the GEFS on this.





Here's the chance of rain at Deer Park from the NBM (blend of multiple models) for the next 10 days.  You can see the odds of showers start to ramp up Tuesday, and really increase by Thursday.



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