August 2023 Weather in the PNW

[Cloud]

A very fall-like morning with the deep marine layer intrusion. Feels nice!

[TT-SEA]

The only way its fall is if we have well below 500mb heights?   It will still be fall even when we have inevitable ridging in September and October.   Just like our mega-trough in June was still summer.    

On a side note... we might get to do some water activities this coming weekend per the EPS even though its winter now.  

 

[Phil]

00z EPS looks nice out there!

[TT-SEA]

06Z ECMWF on the fun coming tonight and tomorrow morning.  

 

[Phil]

Anecdotally it’s always seemed to me that the Atlantic waking up signals the start of the seasonal transition in the synoptic pattern/WT, with the muted/quiet years having the most consistent low frequency ET patterns.

Of course I can’t prove this, and given the timing it could simply be a coincidence.

[Cloud]

16 minutes ago, TT-SEA said:

06Z ECMWF on the fun coming tonight and tomorrow morning.  

 

Guess I'm busting out the rain jacket tonight for work! 

[Phil]

FWIW, the east-based niño/p8 structure in tropical forcing statistically favors a troughy pattern in the west during S/O/N.

Come D/J/F that reverses, of course.

[TT-SEA]

3 minutes ago, Phil said:

Anecdotally it’s always seemed to me that the Atlantic waking up signals the start of the seasonal transition in the synoptic pattern/WT, with the muted/quiet years having the most consistent low frequency ET patterns.

Of course I can’t prove this, and given the timing it could simply be a coincidence.

I would say the Earth's axial tilt and it's orbit around the sun are also responsible.   

 

[Cloud]

7 minutes ago, Phil said:

Anecdotally it’s always seemed to me that the Atlantic waking up signals the start of the seasonal transition in the synoptic pattern/WT, with the muted/quiet years having the most consistent low frequency ET patterns.

Of course I can’t prove this, and given the timing it could simply be a coincidence.

Anecdotally, I look at the Western Pacific and have been last couple years during this time of the year since my wife is currently there, but what I noticed is that their monsoon season (starting in June) is starting to wind down now, with rain and t-storms becoming less frequent as we transition to fall  here. Obviously, I can't prove this either, but it's what I've been noticing last couple years since I start monitoring the SE Asia weather more frequently. 

[Phil]

1 minute ago, TT-SEA said:

I would say the Earth's axial tilt and it's orbit around the sun are also responsible.   

 

Now that’s a radical, groundbreaking take if I’ve ever heard one.

[Phil]

1 minute ago, Cloud said:

Anecdotally, I look at the Western Pacific and have been last couple years during this time of the year since my wife is currently there, but what I noticed is that their monsoon season (starting in June) is starting to wind down now, with rain and t-storms becoming less frequent as we transition to fall  here. Obviously, I can't prove this either, but it's what I've been noticing last couple years since I start monitoring the SE Asia weather more frequently. 

ASM forcing definitely matters, and on very large scales. Your intuition is correct.

[Phil]

The phase-8 RMM often associated w/ warm west/cold east in the winter actually favors the opposite for almost all of autumn and even the first half of December.

It isn’t until the holiday season that the winter teleconnection establishes.

[Dave]

Some light drizzle here this morning. Not much, but it is refreshing. 

[TigerWoodsLibido]

Cool and pleasant morning.

[Port Angeles Foothiller]

[FroYoBro]

Actually a few little drops of moisture falling on my car this morning. This week will be a nice change of pace! 

[Rubus Leucodermis]

AQI around 115 this morning.

860 at Diablo Dam on the Skagit River and 657 at Kanaka Bar in the Fraser Canyon.

[BLI snowman]

1 hour ago, Phil said:

The phase-8 RMM often associated w/ warm west/cold east in the winter actually favors the opposite for almost all of autumn and even the first half of December.

It isn’t until the holiday season that the winter teleconnection establishes.

Which also aligns with the way Ninos tend to actually be sort of favorable for us in the first half of the season. Even the horrifically bad ones (1991-92, 2014-15) are typically very front-loaded with the cold opportunities that we do see.

Edited August 28 by BLI snowman

[Chewbacca Defense]

1 hour ago, TT-SEA said:

I would say the Earth's axial tilt and it's orbit around the sun are also responsible.   

 

Would that have any impact on sun angles?

[Cloud]

6 minutes ago, Chewbacca Defense said:

Would that have any impact on sun angles?

We’re losing so much daylight now! Did that answer the question?

[LowerGarfield]

My wife took this photo of a mantis, hanging out on our doorbell. This is the time of year when we start seeing them everywhere, late Aug/Sept. Non native but still cool.

[SilverFallsAndrew]

Now this is a marine push.

[iFred]

23 minutes ago, Chewbacca Defense said:

Would that have any impact on sun angles?

I feel attacked.

[Cloud]

14 minutes ago, LowerGarfield said:

My wife took this photo of a mantis, hanging out on our doorbell. This is the time of year when we start seeing them everywhere, late Aug/Sept. Non native but still cool.

Every time I see a mantis, it instantly reminds me of the one that preyed on a hummingbird and eating it. I swear, if this thing is big enough, it could eat a human.

[iFred]

2 hours ago, TT-SEA said:

The only way its fall is if we have well below 500mb heights?   It will still be fall even when we have inevitable ridging in September and October.   Just like our mega-trough in June was still summer.    

On a side note... we might get to do some water activities this coming weekend per the EPS even though its winter now.  

 

I’ve got to finish reseeding and a couple other landscape projects, so kind of banking on our typical September and October warmth

[Front Ranger]

7 minutes ago, iFred said:

I’ve got to finish reseeding and a couple other landscape projects, so kind of banking on our typical September and October warmth

Last year aside, that's been a lot less dependable than July/August warmth. 2021, 2019, 2018, 2016, and 2015 all had seasonable to cool Septembers.

[SilverFallsAndrew]

Right now if we look at SLE, they should still end up with their hottest August ever, beating out August 2017. However, it may be close in terms of whether or not they can beat out July 2021 for hottest month ever. Right now if they hit the NWS forecast marks they will tie it. However, any under achievement and things will be tough. Forecast high today is 81, gonna need some clearing to make it. 

[BLI snowman]

Looks like the first storms are firing up now on the northern Hood Canal.

[BLI snowman]

15 minutes ago, SilverFallsAndrew said:

Right now if we look at SLE, they should still end up with their hottest August ever, beating out August 2017. However, it may be close in terms of whether or not they can beat out July 2021 for hottest month ever. Right now if they hit the NWS forecast marks they will tie it. However, any under achievement and things will be tough. Forecast high today is 81, gonna need some clearing to make it. 

Definite underachiever potential for highs these next few days, given the depth of the stratus and the lack of mixing with this thing staying a bit parked.

[Front Ranger]

6 minutes ago, SilverFallsAndrew said:

Right now if we look at SLE, they should still end up with their hottest August ever, beating out August 2017. However, it may be close in terms of whether or not they can beat out July 2021 for hottest month ever. Right now if they hit the NWS forecast marks they will tie it. However, any under achievement and things will be tough. Forecast high today is 81, gonna need some clearing to make it. 

Different story further north, at least away from PDX (which should easily have their hottest August/month on record).

Downtown Portland, Battle Ground, Longview, OLM, and SEA will all fall short of hottest August or month. July 1958 or August 1967 remain the king for downtown Portland and the rural stations, while July 2015 remains hottest month for SEA, and August 1967 remains the hottest August.

My guess is August 1967 will remain #1 for Silver Falls as well.

[Front Ranger]

NHC expects Idalia to become a hurricane very soon and reach Cat 3 by landfall: https://www.miamiherald.com/news/weather/hurricane/article278677029.html

[BLI snowman]

12z GFS would be an absolute godsend for western OR. Stratiform rain all day Thursday with highs in the low 60s. 

The Canuck sucks, unfortunately.

[ChristheElohim]

[seattleweatherguy]

3 hours ago, Phil said:

The phase-8 RMM often associated w/ warm west/cold east in the winter actually favors the opposite for almost all of autumn and even the first half of December.

It isn’t until the holiday season that the winter teleconnection establishes.

So up until the second half of December there could be snow? Otherwise not possible the rest of the year? Sounds like 2019

[Cloud]

Look like we’re getting the convective party started. Got startled by fat rain drops hitting the roof with this one popping right on top of me. Didn’t know what the hell was going on outside. 

[Cascadia_Wx]

Cloudy and drizzly here, with the marine layer all the way up to the Cascade crest. Reminds me of the olden days. Looks like PDX has picked up 0.03” this morning in drizzle. About the same here.

Currently 63 after a low of 61.

[Cloud]

The cell that was right over me really exploded as it zoomed north. So are the other cells. Fun!

[Meatyorologist]

Seattle is about to hear some thunder. Still in Cle Elum right now... Headed back home soon. Great sign for tonight.

[Front Ranger]

12z GEFS keeps troughing going through foreseeable future.

 

[Cascadia_Wx]

49 minutes ago, BLI snowman said:

12z GFS would be an absolute godsend for western OR. Stratiform rain all day Thursday with highs in the low 60s. 

The Canuck sucks, unfortunately.

Really hoping the Euro still shows something similar. Should find out in the next few frames.

[Hawksfan2008]

Been a while friends! Looking forward to more exciting weather as we head towards fall. Speaking of which, BOOM! 

[Cascadia_Wx]

14 minutes ago, Cascadia_Wx said:

Really hoping the Euro still shows something similar. Should find out in the next few frames.

12z Euro is washed out trash for the Thursday system down here. Hopefully it makes a comeback on the next run. Last nights 00z was pretty good.

[Cascadia_Wx]

Looks like the 12z Euro redeems itself a bit by being much wetter over the long weekend.

[Phishy Wx]

2 hours ago, BLI snowman said:

Which also aligns with the way Ninos tend to actually be sort of favorable for us in the first half of the season. Even the horrifically bad ones (1991-92, 2014-15) are typically very front-loaded with the cold opportunities that we do see.

white Halloweens around here, usually white t-giving.  likely brown xmas/NYE in similar scenarios 

[Phishy Wx]

 

 

[SilverFallsAndrew]

Looks like a lot of rain coming for folx north of Seattle. 

[Anti Marine Layer]

11 hours ago, Cloud said:

European rain totals.

Not as much as Hilary.

[Omegaraptor]

1 hour ago, Front Ranger said:

12z GEFS keeps troughing going through foreseeable future.

 

Tim finally got tired of the heat and ridging and fired up the weather machine?

[TT-SEA]

70+ steak ends today at SEA rare swing and miss by ECMWF with marine stratus.   GFS actually did much better.   

[Meatyorologist]

Driving west on I90, I can see the anvils of the storms over the Sound right now. Some overshooting tops