As I was picking up dinner for my family yesterday evening, I noticed that the restaurant patios in my neighborhood were packed.  Let’s face it; we all know al fresco dining is much harder to come by as we get closer to our wet season.  This likely explains why patio seating is at a premium on clear and mild September evenings. 

Chances are that you have been enjoying your backyard deck or maybe some outdoor dining at your favorite restaurant.  Coming off the driest August on record in Seattle, rain has been steering clear of Western Washington through this first week of September.  In fact, we have to go back to July 22^nd to find the last day with measurable rainfall at Sea-Tac Airport. 

With sunny skies and upper 80s today, this will be the 47^th consecutive dry day at the airport; the second longest dry streak on record for Seattle.  The all-time driest stretch was back in 1951 when we went 51 days without rain.   In order for us to tie that record, we have to make it through next Tuesday without rainfall.  Now that the record is only a few short days away, it’s looking more and more likely that we will fall short of breaking it. 

Rain chance improving

We have to look way out to the Bering Sea where an area of low pressure is sitting just north of the Aleutian Islands.  This trough will be moving southeast over the coming days, bringing rain into our area Sunday evening through Monday morning. 

Computer forecast models keep the heaviest rain north of Seattle and along the coast.  Rainfall estimates between 0.25” and 0.50” are possible, especially the closer you get to the Canadian border.  Around Sea-Tac airport, much less rainfall is expected.  The central sound will be in the rain shadow of the Olympic Mountains, so forecast rainfall totals are less than 0.10”.  All it takes is 0.01” to break the dry streak. 

With the best chance of showers at Sea-Tac being overnight Sunday into Monday morning, it looks like the streak will end with either 48 or 49 days in the book.  If the rain holds off until after midnight, it will be 49 days.  If it’s before midnight, it will be 48 days.  Of course, there is always the chance that the rain falls apart before making it into Sea-Tac.  If that’s the case, the record will still be alive and we expect to break it with a dry forecast in Seattle on Tuesday and Wednesday.  Stay tuned, we’re down to the wire! 

-Sam Argier, KIRO 7 Morning Meteorologist