June Weather in the Pacific Northwest

[Jbolin]

Just took a look at meso data and WAAAAAAY better dynamics here in Wa than down in OR

[TT-SEA]

Need to check the Euro. No updates on it so hopefully a good sign!!

 

 

Very nice run!

 

I got pulled into a training session.

[Front Ranger]

Live look outside the weather window... I will say late June/July are one in the same now. Used to not really feel like summer until around the 4th of July. Last 5-6 years it has been Mid-May.

 

 

There has been a shift for sure in recent years, but it hasn't been entirely one-sided towards longer warm seasons.

 

3 of the last 5 Septembers have been near normal to below normal across the region. Meanwhile, every single May and June since 2012 has been above normal (most well above) except for June 2014. 

 

So I think the shift has been heavily towards warmer late springs/early summers. Sort of a bounce back from a period that was pretty cool overall 2007-12, save 2009.

[TT-SEA]

I often wonder, who cares if the weekend is nice or not if every day is your weekend?

 

Weekends matter!  

 

The entire family is together... no school and no work.  

[TT-SEA]

There has been a shift for sure in recent years, but it hasn't been entirely one-sided towards longer warm seasons.

 

3 of the last 5 Septembers have been near normal to below normal across the region. Meanwhile, every single May and June since 2012 has been above normal (most well above) except for June 2014. 

 

So I think the shift has been heavily towards warmer late springs/early summers. Sort of a bounce back from a period that was pretty cool overall 2007-12, save 2009.

 

 

December, January, and September have been the consistently dry months up here in recent years.

 

February, March, and October always seem to deliver copious rain lately.   Wet going into dry season and wet coming out of dry season.  

 

[Front Ranger]

A "wet August" is not even a thing in the Willamette Valley. I remember some cool troughy/somewhat wet periods in late August 20-25 years ago, but that is about it. 

 

The last time SLE had 1"+ of rain in August was 2008. 

 

SLE has actually only had 2"+ of rain in August 6 times since 1892. Only once did they exceed 3", when they received 4.17" of rain in August 1968. One legitimately wet August in 126 years. 

 

Hell, SLE has only had over 4" in June twice ever. August 1968 was a Jesse wet dream...and not just because it was the height of hippie mania.

[Front Ranger]

Definitely a little troughier overall on Monday and Tuesday. Then a mid week relaxation in troughing before more swings in later on.

 

Looks decidedly normalish overall after today.

[Front Ranger]

I often wonder, who cares if the weekend is nice or not if every day is your weekend?

 

On this forum, sometimes it feels like every day is Monday...

[Phil]

Lol.

 

Tbh, I think it’s difficult to project from arbitrary parameters like PNW rainfall during seasonal transitions, since that is largely subject to nonlinear intraseasonal dynamics rather than lower frequency boundary conditions. Often times it either tells you nothing or arises from a decaying boundary state structure which speaks more to the past than the future.

 

I’m personally relying on -QBO years with enhanced zonal SST gradients across the tropical Pacific, with colder IO/NATL and/or +PMM years getting more weight during the J/J/A/S/O period versus years lacking those analogous peripheral circulations.

In which case, you could theoretically argue for a range of possible years/outcomes, most of them before 1998.

 

In various ways, 2001, 1996, 1987, 1985, 1984, 1979, 1977, 1970, 1968, 1965, and 1963 meet some/most of these requirements. But there’s still a very large degree of variance in there. However, that can be somewhat reconciled by tuning for low frequency structural homogeneities beneath the intraseasonal oscillations.

[Front Ranger]

Lol.

 

Tbh, I think it’s difficult to project from arbitrary parameters like PNW rainfall during seasonal transitions, since that is largely subject to nonlinear intraseasonal dynamics rather than lower frequency boundary conditions. Often times it either tells you nothing or arises from a decaying boundary state structure which speaks more to the past than the future.

 

I’m personally relying on -QBO years with enhanced zonal SST gradients across the tropical Pacific, with colder IO/NATL and/or +PMM years getting more weight during the J/J/A/S/O period versus years lacking those analogous peripheral circulations.

 

Gotcha. 

 

So what would you say are the top 5 overall matches in terms of QBO/SST gradients right now?

[TT-SEA]

Looks decidedly normalish overall after today.

 

 

Perfect.

[BLI snowman]

There has been a shift for sure in recent years, but it hasn't been entirely one-sided towards longer warm seasons.

 

3 of the last 5 Septembers have been near normal to below normal across the region. Meanwhile, every single May and June since 2012 has been above normal (most well above) except for June 2014. 

 

So I think the shift has been heavily towards warmer late springs/early summers. Sort of a bounce back from a period that was pretty cool overall 2007-12, save 2009.

 

OLM hasn't seen a September departure of -1 or less since 2005.

[TT-SEA]

12Z EPS starts warming up around day 7... nothing crazy but definitely not showing deep troughing.

 

Out through day 14 now... here is the day 9-14 mean:

 

[Phil]

Gotcha.

 

So what would you say are the top 5 overall matches in terms of QBO/SST gradients right now?

Matches are great, however, your guess is as good as mine re: which ones have the right progressions running forward. You can have years with matching boundary conditions, but are progressing in opposite directions, metaphorically speaking.

 

My hunch is, if you want to avoid unnecessary complexity, just go simple and run with weak ENSOs that are warmer in the WPAC and colder in the EPAC, ideally with warm Pacific/cold Atlantic peripherals (which tend to occur from the 1960s to the 1990s). Then maybe weight for QBO and solar if you’re happy with your sample size.

 

But it’s no guarantee, haha. I’ve screwed this up many times in the past.

[Jbolin]

Moving along the crest.

Moving east

[Phil]

That’s a strong GOA ridge signal on the D15 EPS.

 

Climatologically speaking, a quasi-stationary GOA/EPO style ridge favors a weaker 4-corners high but also a relatively dry PNW/BC.

 

However, in a +NAO/Baffin vortex regime, it’s not a guarantee, since EPAC tropical activity/off-eq convection is often enhanced under a +NAO/-EPO circulation.

 

[Phil]

12Z EPS starts warming up around day 7... nothing crazy but definitely not showing deep troughing.

 

Out through day 14 now... here is the day 9-14 mean:

 

Ugh..that’s the most humid pattern possible here.

[Phil]

And, unfortunately for some/fortunately for others, the probability of a warm S/O/N is increasing.

 

The vast majority of +PMM/dateline forcing analogs tend to build +PNA/west coast anticyclones starting in late August or September. There are exceptions, though.

 

Watch the Antarctic Oscillation & AMO. The older years w/ more -AAO/-AMO in JJA run much colder in the west during S/O/N.

[Jbolin]

My apologies.

NP

[TT-SEA]

Strange to have all the blow off from the convection heading to the west and northwest while the cells are moving to the east.  

 

Obviously some wind shear at the upper levels.  Normally the blow off clouds are moving in the same general direction as the cells.

[El Nina]

88 at PDX per the 2 o'clock observation. 90 is a lock.

[Jesse]

#4!

[Jesse]

88 at PDX per the 2 o'clock observation. 90 is a lock.

Never underestimate PDX.

[FroYoBro]

91 here. 

[TigerWoodsLibido]

85 here and cooler as you go down the valley. Doubt we see any action.

[Front Ranger]

OLM hasn't seen a September departure of -1 or less since 2005.

 

And the western lowlands haven't seen a May or June with anomalies like this since 2012. Point stands...the warmth has been heavily weighted towards early in the warm season.

 

 

[Phil]

This is freaking hilarious. No matter how the pattern changes elsewhere, Baffin Island and Greenland stay in the freezer. Nothing budges the vortex.

 

First 3 images are the EPS control run, the second 3 are the EPS mean.

 

D1-5:

 

 

D5-10:

 

 

D10-15:

 

 

D1-5:

 

 

D5-10:

 

 

D10-15:

 

[Front Ranger]

And, unfortunately for some/fortunately for others, the probability of a warm S/O/N is increasing.

 

The vast majority of +PMM/dateline forcing analogs tend to build +PNA/west coast anticyclones starting in late August or September. There are exceptions, though.

 

Watch the Antarctic Oscillation & AMO. The older years w/ more -AAO/-AMO in JJA run much colder in the west during S/O/N.

 

Sounds like it's time to crank up that fall forecast contest!

[Front Ranger]

Never underestimate PDX.

 

Until they smash their all-time high, PDX is still playing second fiddle to SEA, though.

[FroYoBro]

Some really impressive looking storms on radar east of Corvallis. 

[El Nina]

Some really impressive looking storms on radar east of Corvallis.

 

You mean Eugene?

[BLI snowman]

And the western lowlands haven't seen a May or June with anomalies like this since 2012. Point stands...the warmth has been heavily weighted towards early in the warm season.

 

Sep16TDeptWRCC-NW.png

 

Sep15TDeptWRCC-NW.png

 

Nah, we had two roughly average Septembers and that's it. Last September was scalding, 2014 was an inferno, 2013 was very mild, 2012 was slightly warm, and 2011 was torchified. September has very heavily been weighted towards the hot side this decade, as of course has August. It takes some real mental gymnastics to argue against the idea that our summers have been extending on both ends lately.

[Perturbed Member]

Radar looking decent Cascades and east. 

 

The National Weather Service in Portland has issued a

* Severe Thunderstorm Warning for...
Southeastern Marion County in northwestern Oregon...

* Until 345 PM PDT..

* At 308 PM PDT, a severe thunderstorm was located near Detroit, and
is nearly stationary.

HAZARD...Half dollar size hail.

SOURCE...Radar indicated.

IMPACT...Damage to vehicles is expected.

* This severe thunderstorm will remain over mainly rural areas of
southeastern Marion County.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Prepare immediately for large hail and deadly cloud to ground
lightning. Seek shelter inside a well-built structure. Stay away from
windows.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

[Farmboy]

[Farmboy]

 

HAZARD...Half dollar size hail.

 

SOURCE...Radar indicated.

 

IMPACT...Damage to vehicles is expected.

 

 

 

 

Wow, that is some real midwest type there...

[El Nina]

Now a severe warning for SE Clackams county.

[Dave]

There's a decent streaming webcam that you can view a nice storm with. Click the "downtown" link.

 

http://www.eyeonbend.com/

[Deweydog]

I swear someone at the NWS office is messing with J-dog.

[Jesse]

There's a decent streaming webcam that you can view a nice storm with. Click the "downtown" link.

 

http://www.eyeonbend.com/

Cool link. I have been watching that storm to the south of town on it.

[Dave]

Eugene is boned. Marine push apparently here. Down to 73 degrees.