September 2019 Weather Discussion for the PNW

[TacomaWaWx]

Safe to say the latest gfs run is not backing down. Feeling a little more confident about this now but will see how this goes for a couple more days.

[Phil]

Could it be that we're seeing lag still from the Nino last winter?

I wouldn’t call it lag, since the coupling is still present and the system state (+IOD/Cool Indo-Pacific/+PMM/dateline warm pool) is very well-established. Where the system goes in F/M/A 2020 is debatable..some forecasters are thinking the beginning of the move to the heavy multiyear La Niña/-PMM/-PDO starts next spring/summer, but I’m not so sure. I think that happens a year later (2021/22) now, but that’s way out there.

[Jesse]

He made a forecast that made no sense

For the warm September did not commence

Now he's hoping to even the score

While with every trough, he'll cry some more

The frost will come, the leaves will turn

And much to his despair, the fires won't burn

Ooooohhhhh...now I wanna write a Tim/Dewey poem!

[Phil]

Both 1971 and 1985 were not +ENSO. Throw them out.

 

- Phil Seymour Hoffman

I wouldn’t throw 1985 out.

[Front Ranger]

I wouldn’t call it lag, since the coupling is still present and the system state (+IOD/Cool Indo-Pacific/+PMM/dateline warm pool) is very well-established. Where the system goes in F/M/A 2020 is debatable..some forecasters are thinking the beginning of the move to the heavy multiyear La Niña/-PMM/-PDO starts next spring/summer, but I’m not so sure. I think that happens a year later (2021/22) now, but that’s way out there.

Perhaps. But it's possible Jim is right...what we've seen to this point is remnants of last winter's regime, and now the atmosphere is turning as the ENSO lag fades.

 

A neutral system state is very much on the table for this winter, I think.

[TigerWoodsLibido]

I wouldn’t throw 1985 out.

 

Oh boy...

[Front Ranger]

I wouldn’t throw 1985 out.

Good man. Solar min after all...

[Jesse]

00z looks pretty darn cold.

[Phil]

Perhaps. But it's possible Jim is right...what we've seen to this point is remnants of last winter's regime, and now the atmosphere is turning as the ENSO lag fades.

 

A neutral system state is very much on the table for this winter, I think.

We’ll see, I guess.

 

But keep in mind, the structure of tropical convection right now is very El Niño-like..one of the strongest phase 8/1 MJO cycles for mid/late September in recent decades. So it’s hard to argue that the atmosphere is moving “away” from El Niño, in that context.

 

What you’re seeing now across in the middle latitudes is a consequence of the culminating cycle of AAM transport poleward and the seasonal transition in the wavenumber/ET dynamics. With time, these boundary conditions must change. Question is, how will the wavetrain respond?

[Requiem]

00z looks pretty darn cold.

 

It does, for sure. In fact I would say it's a tad bit colder than the 18Z.

[TacomaWaWx]

It does, for sure. In fact I would say it's a tad bit colder than the 18Z.

Id have to agree. Very good run little less than 4 days out now.

[Requiem]

Geez, 00Z stays pretty chilly too. Nothing like a week out from now, but not a bad start, I would say

[Jesse]

[GHweatherChris]

Smh

[Jesse]

Smh

 

What are we in trouble for this time, Chris? 

[VancouverIslandSouth]

Another 0.27" of rain today, brings the monthly total to 2.41"; not bad for September.

[Omegaraptor]

Geez, 00Z stays pretty chilly too. Nothing like a week out from now, but not a bad start, I would say

 

00z GFS is entertaining the possiblity of frost in Roseburg on 9/30 and 10/1. They have only ever experienced September frost once - and it was 32ºF on September 30, 1954.

 

Actually, the morning of the 30th looks pretty impressive just about everywhere in the NW:

 

[Geos]

This has been quite the wild weather month. Been enjoying the weather ride ever since those strong thunderstorms came through that one night. Getting kind of windy out there tonight. Will be interesting to see how early we have a frost in the Puget Sound area. 

 

Been a couple hectic months for me and now that things are calming down - I can spend time again here. 

[Requiem]

This has been quite the wild weather month. Been enjoying the weather ride ever since those strong thunderstorms came through that one night. Getting kind of windy out there tonight. Will be interesting to see how early we have a frost in the Puget Sound area. 

 

Been a couple hectic months for me and now that things are calming down - I can spend time again here. 

 

Yes, it hasn't been a bad summer by any definition (unless one's definition is constant torching-- if then, it was terrible). Strong thunderstorms for both Portland and Seattle. Strong wind for Portland a week ago or two. Heavy rain for both cities from convective events. And no smoke! I'd call it a win!

 

I'm glad things are settling down for you, as well.

[Deweydog]

He made a forecast that made no sense

For the warm September did not commence

Now he's hoping to even the score

While with every trough, he'll cry some more

The frost will come, the leaves will turn

And much to his despair, the fires won't burn

Is that James Joyce?

[Geos]

Up to 4.25" of rain here for the month. Last September only 1.79" and that was for all 30 days. 

[ShawniganLake]

I'm getting more excited about this event the more I look into it. It appears that getting both a fantastic 500mb pattern and a Canadian surface high dropping over us is tremendously rare this early in the season. We could threaten some all time records for cold so early in the season. Landsburg doesn't have a low on record below 29 until October 8. Most of the years that did get to freezing in late Sept / early Oct went on to be very good winters. I have some research to do!

How far back does landsburg have records. September records for wind sheltered areas here are 23 to 25F. From 1926. We won’t be close to that this time.

[Timmy Supercell]

Yeah in the PDX area you'd have to dig quite a while back to actually match a snow that occurred during the hours of Trick or Treating (or even right before or after). Hell, even where I live now in a place that gets 10x more snow, probably has not seen Halloween snow in quite some years. Generally October snow isn't unheard of, but it was probably somewhere in the 1980's when a Halloween snow last happened.

 

I know I live right by people who will say "it can snow in July in K-Falls" but how often exactly does that occur, 1 in every 20-25 years. 

I have an uncle who's been here since 2006 and has not seen snow later than the 3rd week of June or sooner than the first week of October. 

[TacomaWaWx]

00z GFS is entertaining the possiblity of frost in Roseburg on 9/30 and 10/1. They have only ever experienced September frost once - and it was 32ºF on September 30, 1954.

 

Actually, the morning of the 30th looks pretty impressive just about everywhere in the NW:

 

Lots of 30s in the lowlands.

[TacomaWaWx]

This has been quite the wild weather month. Been enjoying the weather ride ever since those strong thunderstorms came through that one night. Getting kind of windy out there tonight. Will be interesting to see how early we have a frost in the Puget Sound area.

 

Been a couple hectic months for me and now that things are calming down - I can spend time again here.

Thunderstorms on 9/7 and 9/12 were pretty great. Has been a fast and sudden onset of fall, looks like it really steps it up a notch this weekend if the forecasts verify. 2.65” of rain so far this month.

[Front Ranger]

How far back does landsburg have records. September records for wind sheltered areas here are 23 to 25F. From 1926. We won’t be close to that this time.

That's insane for the lowlands.

[Geos]

Thunderstorms on 9/7 and 9/12 were pretty great. Has been a fast and sudden onset of fall, looks like it really steps it up a notch this weekend if the forecasts verify. 2.65” of rain so far this month.

 

You're getting shawdowed down there a bit. 

[BLI snowman]

Yeah in the PDX area you'd have to dig quite a while back to actually match a snow that occurred during the hours of Trick or Treating (or even right before or after). Hell, even where I live now in a place that gets 10x more snow, probably has not seen Halloween snow in quite some years. Generally October snow isn't unheard of, but it was probably somewhere in the 1980's when a Halloween snow last happened.

 

I know I live right by people who will say "it can snow in July in K-Falls" but how often exactly does that occur, 1 in every 20-25 years. 

I have an uncle who's been here since 2006 and has not seen snow later than the 3rd week of June or sooner than the first week of October. 

 

 

Actually, the only appreciable October snowfall in Portland area history was on October 29, 1935. There may have also been a dusting in October 1835 according to early records, so I guess we'll be due again in 16 years.

[BLI snowman]

Is that James Joyce?

 

Lord Byron

[MossMan]

1985 was all about November. Historically cold and snowy. It was then followed by a cold and dry December. Some place had snow on the 2nd or thereabouts.

I had just turned 9yrs old and got to experience my first last minute school cancellation as I waited at the bus stop in a driving snowstorm...that was wonderful! Lake Goodwin froze over and there are pics of me in snow up to my waist. Good times!

[ShawniganLake]

That's insane for the lowlands.

From September 22-25, 1926 the Duncan station went 26F, 23F, 25F, 29F for lows.

[MossMan]

Up to .45” on the day. Windy and wet, feels like late October out there!

[GHweatherChris]

What are we in trouble for this time, Chris?

Lol, noone, just hoping the conversation about the upcoming cool snap coming happens a few times during winter, but with brutal cold. Tough for me to be excited for a September snap.

[TacomaWaWx]

You're getting shawdowed down there a bit.

We we’re on the lower end of the totals that some places got. Still roughly an inch above average for the month.

[Deweydog]

Lol, noone, just hoping the conversation about the upcoming cool snap coming happens a few times during winter, but with brutal cold. Tough for me to be excited for a September snap.

The thought police have two units en route your residence. Prepare accordingly.

[GHweatherChris]

The thought police have two units en route your residence. Prepare accordingly.

Locked and loaded, #2ndAmendment!!

[Deweydog]

Euro!!!

[Jesse]

The thought police have two units en route your residence. Prepare accordingly.

[Jesse]

Surprising number of GFS ensemble members going below 0c around days 5-7.

[Deweydog]

Surprising number of GFS ensemble members going below 0c around days 5-7.

Definitely surprising considering how warm the op is around that time.