September 2019 Weather Discussion for the PNW

[Requiem]

18Z GFS is nice... glad I broke my rule and checked it out.

 

Very little rain for the next 12+ days after tomorrow.

 

I'd prefer, ya know, wetter, but that's okay too I guess.

 

EDIT: I looked at it, and it's as bleh as I'd imagined!

[TT-SEA]

66 and mostly sunny here... ended up with a lovely afternoon.

[Phil]

The background state from April - June was more ridgy than not. Which helps explain why it was so dry.

 

phyllus.png

I forecasted May-Sep. The same “background” tropical forcing structure will teleconnect differently to the mid-latitude wavetrain in April vs the summer months..you have to be careful with the timeframe you use.

 

April-June makes little dynamic sense if you’re looking to run any sort of seasonally-independent correlations for analogs. I never make forecasts for that trimonthly period since it’s almost always transitional even w/ unchanging forcing on the low pass.

[Frontal Snowsquall]

I hate when storms impact the Sunday morning commute

I commute 45-50 mins to work. Fortunately my church commute is less than 5 mins.

[ShawniganLake]

He’s trolling a little. Would probably be the first to admit it.

 

Although I can definitely see the draw to trolling Flatiron’s tendency to overplay recent or incoming airmasses.

I’m curious to see how this plays out down here. Feels like we’ve played with these early season continental airmasses before. And the results often end up milder than people might expect, at least up this way. Some 70/45 type weather with a NNE wind on Saturday wouldn’t be too surprising in SW BC. Then we’ll see who escapes the wind on Sunday/Monday as too who sees any possible frosts.

[Frontal Snowsquall]

Yeah, an Arctic airmass filtered into WA on the 6th and got hung up just south of Portland. Like Dewey said, a warm front swung in and a baroclinic band intensified along the OR/WA border on the 7th and persisted through the 8th and 9th.

 

There was an incredible gradient across the Portland metro where the upper level boundary stalled. Everyone in the metro area west of the West Hills and south of about Stark Street had just a few inches of snow but got a major ice storm with 1-2" of freezing rain. Portland was the transition zone and everywhere east of I-205 or north of the Columbia had about 48 hours straight of heavy snow. There were 20-30" totals throughout Vancouver and Gresham, and outlying areas like Ridgefield had about 3 feet over the three days.

 

The gorge was absolutely paralyzed with 71.5" in 3 days at Hood River.

 

Interestingly that storm also peaked 100 years to the day after the 1880 craziness.

I didn't know that storm dumped that much snow out here on the east side. Wish I was alive to experience it.

[ShawniganLake]

Calgary could see a sub freezing high on Saturday. I don’t believe they have recorded that in September before.

[TacomaWaWx]

Wasn’t very much sun here today. 64/58 0.11” of rain.

[ShawniganLake]

Pretty impressive to see a Winter storm Watch for north east Wa. Earliest I've ever saw.

You had a fair bit of snow at your cabin last September didn’t you. I seem to remember you posting pics.

[Frontal Snowsquall]

PDX is the driest place in the Portland metro, isn’t it?

 

They record about 36”/year. Tualatin Valley is the next driest place in the metro.

Here's a map Mark posted a few years ago showing average annual rainfall around the area.

 

1. The driest parts of the metro area are in the lowest elevations in the Tualatin Valley and along the Columbia River from Vancouver Lake to NE Portland.  That includes the Hillsboro, Portland, and Vancouver airports.  These areas typically average less than 38″ of rain each year.  Another dry spot, although not quite as dry, is the northern Willamette Valley south of Wilsonville.

 

 

https://fox12weather.wordpress.com/2015/09/06/

[Front Ranger]

I changed it. Happy now?

I don't care, just want consistent forum moderation.

[Front Ranger]

I’m curious to see how this plays out down here. Feels like we’ve played with these early season continental airmasses before. And the results often end up milder than people might expect, at least up this way. Some 70/45 type weather with a NNE wind on Saturday wouldn’t be too surprising in SW BC. Then we’ll see who escapes the wind on Sunday/Monday as too who sees any possible frosts.

I don't think we've seen many early season blocking setups like this recently.

 

But maybe that's just my recent/anti-recent bias talking!

[Phil]

I don't care, just want consistent forum moderation.

Karma’s a b*tch.

[Phil]

I don't think we've seen many early season blocking setups like this recently.

 

But maybe that's just my recent/anti-recent bias talking!

Not recently, no. But the 1960s were loaded with them.

 

And the 1950s to some extent as well.

[Front Ranger]

Karma’s a b*tch.

Just ask Kevin Martin.

[Phil]

Lorenzo is a Cat4 hurricane in the E-ATL MDR. Amazing how quickly we’ve bulldozed through the alphabet lately.

 

Seems the return of strong Atlantic hurricanes has also coincided with some cooler (or less death ridgy) PNW autumn patterns in recent years.

[Phil]

Talk about a huge disconnect between the tropical/seasonal background system state and the subseasonal/ET-M AAM gradient. This should resolve in time but still..lol.

 

The low pass tropical forcing structure is analogous to that of a healthy El Niño right now, in many ways:

 

[BLI snowman]

We're secretly in a super Nino right now and the government just doesn't want to admit it.

[Front Ranger]

The atmosphere fell for last winter's head fake so hard, it still thinks we have a Nino.

[MossMan]

Arctic Blast!

https://cliffmass.blogspot.com/2019/09/arctic-express-coming-to-northwest.html?m=1

[Front Ranger]

Arctic Blast!

https://cliffmass.blogspot.com/2019/09/arctic-express-coming-to-northwest.html?m=1

I think this comment speaks for all of us.

 

[Jesse]

I’m curious to see how this plays out down here. Feels like we’ve played with these early season continental airmasses before. And the results often end up milder than people might expect, at least up this way. Some 70/45 type weather with a NNE wind on Saturday wouldn’t be too surprising in SW BC. Then we’ll see who escapes the wind on Sunday/Monday as too who sees any possible frosts.

Yeah, it seems like you often report relatively balmy conditions when it’s cold down here. This airmass looks to affect the area more equally than some of the recent back door cold shots from the east that have favored the Portland area and Oregon overall, though.

[Frontal Snowsquall]

[Deweydog]

Arctic outbreak.

[MossMan]

Officially .64” on the day. 5.24” for the month.

 

56 degrees currently.

[Front Ranger]

Arctic expresso.

[MossMan]

jaya

[Dave]

Annoying drizzle at the moment. I'm not a fan.

[Deweydog]

Annoying drizzle at the moment. I'm not a fan.

Jesse will be with you shortly.

[Jesse]

[Jesse]

Looks like we ended up hitting 66 today with some late afternoon sunbreaks. Ended up being a pretty afternoon with the sun and collection of low and high clouds moving in. Even spotted a pretty distinct sundog in the Winco parking lot!

 

[Anti Marine Layer]

Meteorological fall started 25 days ago, not 26 days ago.

[Jesse]

Meteorological fall started 25 days ago, not 26 days ago.

 

Grizzly Adams had a beard.

[Deweydog]

[TacomaWaWx]

Looking forward to a pattern change and some chilly fall air to arrive. Should deliver the coolest high temps since May and maybe the coldest overnight lows since late April.

[Jbolin]

Grizzly Adams had a beard.

Grizzly Adams DID have a beard!

[High Desert Mat?]

Hoping I get frost in the next week. Not looking good now, the high desert seems to have lost its muster. If I get below 50 I’ll be happy now.

[Jesse]

Grizzly Adams DID have a beard!

 

Glad someone got the sports reference.

[High Desert Mat?]

Anyone seen my lite brite?

[Deweydog]

Anyone seen my lite brite?

Yes.