Rain Chances for Sunday - Update

 Did anyone notice something a little odd with the weather this morning?  Or was it only me?  Northwest winds were blowing in the tree tops right at sunrise, which is pretty rare at this time of year.  Clearly something was going on.  Turns out a very weak, dry cool front pushed into our area from the north this morning.  It was just a glancing blow, so no big cool down.  But those northwest winds brought drier air in with them, keeping the higher dew points to our south.  Why do I bring this up?  This little event will keep our temperatures a little cooler on Saturday.  Mid-80s instead of near 90F.  And it shouldn't feel muggy either.

Then our much anticipated weak weather system will move in from the Pacific.  The models continue to go all over the place on just how much rain (if any) we can expect.  Here's the latest GFS model (which is once again on the wet side)

And the European model continues to be on the drier side.

The National Blend of Models (which factors in over 100 models) is very bear-ish on this event.

What they all do agree on is the overall timing.  The showers will start Sunday morning in the Cascades, and reach northeast Washington and the Idaho Panhandle by Sunday evening.  Some of these showers could be thunderstorms.

After that, the weather stays warm with highs around 80F through Tuesday.  Then an interesting pattern develops.  You can see below that we will have cool low pressure to our north, and warm high pressure to our south.  This squeeze play puts the jet stream right over us, which will bring us breezy days next week.

I bring this up because there could be good and bad aspects when it comes to harvesting hay.  On the good side, the breezy winds coupled with temperatures in the 70s and dew points in the 30s will really help to cure the hay quickly.

The down side is that this may have an impact on dew formation.  What we want for dew is calm, clear nights.  If the wind persists overnight, dew may be hard to come by.

Here's a forecast of wind speed (thin solid line) and wind gust (dashed line) for Deer Park.  You can see that the wind drops to about 5 mph overnight.  So if you're baling next week and your field is sheltered from the wind, dew will probably still form.  But if your field is in a windy place, then dew might be hard to find.

Looking farther ahead, a trough of low pressure is still predicted to form over the Northwest by next weekend.  This will cool our high temperatures down into the upper 60s.  

This will also bring the threat of afternoon showers.  At this point, this doesn't look like a wet pattern.  But the low pressure looks like it will hang around for the following week.