Pacific NW August 2014 Discussion

[TT-SEA]

Yeah this time of year (late August through late September) is usually my least favorite...especially when it's warm.

 

If there's one thing I cannot stand, it's an Indian Summer

Right... nice fall weather is pretty horrible.

 

BTW - Indian Summer is an October thing after the first freeze. Not something in late August.

 

You also seem to really hate long, cold springs and cold in the summer. And endless snow and wind all winter. At least according to your reports.

 

But I can definitely see how pleasant fall weather with the trees turning color has to be the worst of all!  Those gorgeous 70-degree fall days with chilly mornings are truly horrific.    Much better when leaves are ripped from the trees by cold wind and rain.  

[Phil]

Right... nice fall weather is pretty horrible.

 

BTW - Indian Summer is an October thing after the first freeze. Not something in late August.

Maybe that's what an Indian summer is in the PNW. It usually starts snowing here in the middle of October. It snows in September every now and then. Your dumb definition doesn't necessarily apply to everyone else.

 

You also seem to really hate long, cold springs and cold in the summer. And endless snow and wind all winter. At least according to your reports.

 

But I can definitely see how pleasant fall weather with the trees turning color has to be the worst of all!

I like variability...I hate endless anything. And I despise a warm September.

[TT-SEA]

Maybe that's what an Indian summer is in the PNW, not not in these parts. It usually starts snowing here in mid October.

 

 

I like variability...I hate endless anything.

 

 

Better get that endless cold and snow started very early then!    So you can be complaining about that by early November.

 

God forbid its pleasant in October.     I can totally understand how much you would hate that.  

[Phil]

Better get that endless cold and snow started very early then! So you can be complaining about that by early November.

You wanna talk about complaining? Hahaha.

 

I want variability. Yeah I'll be miserable if this winter features the same s**t 24/7. We went over 5 months without seeing any liquid-form precip in 2013-14.

 

 

God forbid its pleasant in October. I can totally understand how much you would hate that.

We don't get much in the way of pleasant weather here after mid October, dude.

 

http://weatherspark.com/averages/30165/Elkins-West-Virginia-United-States

 

At that stage, consistent warmth requires zonal flow, which leads to endless upslope clouds/fog.

[richard mann]

More quiet boring weather.

As I'd suggested more at the beginning of this week, at this point things looked at generally, should be beginning to move toward showing a bit more definition leastwise.

 

Basic elements as I see things, there's still some amount of heat potential. This with where looking at colder air mass, its having just begun over the past three days to spread more south, while otherwise being set to slow its over-all movement and pace more eastward.

[TT-SEA]

Surprisingly warm with a lack of status given the rather strong trough overhead today.

 

Warm air and even some smoke has rotated in from the north.   

 

Looking at just the 500mb pattern today... I would guess we would be socked in with low clouds and it would be really cool.

 

http://mag.ncep.noaa.gov/data/nam/12/nam_namer_012_500_vort_ht.gif

[Deweydog]

Surprisingly warm with a lack of status given the rather strong trough overhead today.

 

Warm air and even some smoke has rotated in from the north.

 

Looking at just the 500mb pattern today... I would guess we would be socked in with low clouds and it would be really cool.

 

http://mag.ncep.noaa.gov/data/nam/12/nam_namer_012_500_vort_ht.gif

Inside slider.

[richard mann]

-

 

http://www.atmos.washington.edu/weather/sat.shtml

 

http://coastwatch.pfeg.noaa.gov/coastwatch/CWBrowser.jsp?edit=Grid+Data&pointVectorDataSet=%28None%29&synchronizeTimes=true

[Black Hole]

Zonal, (E/-, W/+) but this easterly belt is global and displaced N of the equator (between 10-20N). Already a sign of poleward-propagating AAM balance, which is a tell-tale sign of a -AO regime down the road

Getting back to this thought. So how could you tell from this that there is poleward propagating AAM? Is that obvious from anomalous westerly or easterlies? In other words, how does one draw that conclusion from looking at that map?

 

At any rate I think fall is getting started in the next little bit with the series of troughs coming into the west. Anybody have any ideas on how long it lasts?

[TT-SEA]

Interesting afternoon. Hearing almost constant thunder here for 90 minutes while sitting in the warm sun the entire time.

[richard mann]

-
.. Not to interrupt your exchange with and question more main directed to "Phil" here just above Derrick. But regarding your thought more focused on the idea of ".. fall['s appearing / being set, to be] getting started ... with the series of troughs coming into the west", ...
 
I'd say, more myself, that what's taking shape, along with what's looking to be set to be over the next week to 10 days, is perhaps otherwise looked at, more an indicator as to what—either whether will, or may—come about with fall's truer main approach, more post the 16th of Sept. (where looking at a more specific date).

— This that is, to be more clear, at that point and following, both the main period of more tough-generating cold from the north that we're looking at now more broad-scope, and also, a general recession of cold more, more between the first days of Sept., and Sept. 16th or so.
 
.. Indicator, more an harbinger, than more specific approach, un-changing.
 
— Certainly still, both noteworthy and significant.

[Black Hole]

-

.. Not to interrupt your exchange with and question more main directed to "Phil" here just above Derrick. But regarding your thought more focused on the idea of ".. fall['s appearing / set, to be] getting started ... with the series of troughs coming into the west", ...

 

I'd say, more myself, that what's taking shape, along with what's looking to be set to be over the next week to 10 days, is perhaps otherwise looked at, more an indicator as to what—either whether will, or may—come about with fall's truer main approach, more post the 16th of Sept. (where looking at a more specific date).

 

— This that is, to be more clear, at that point, following both the main period of more tough-generating cold from the north that we're looking at now more broad-scope, and also a general recession of cold more, more between the first days of Sept., and Sept. 16th or so.

 

.. Indicator, more an harbinger, than more specific approach, un-changing.

 

— Certainly still, both noteworthy and significant.

Thanks for the insight and generally I agree. I think September will be more trough-dominated than we have seen in recent years for sure.  

[Phil]

+VP anoms going strong in WPAC.

 

#westerntroughing

 

http://catchmypicture.com/SPDne4.jpg

[Phil]

However, looks like things flip around eventually...finally a legit low frequency wave. It's been like....forever

 

http://catchmypicture.com/f/12C4Gn/640.jpg

[Phil]

The system has been screaming niño for awhile now, but streamfunctions look a hybrid between the Niños of old (pre-1979), and the more recent Niños..

 

Classic Niño circulation leading to equatorialward eddy flux over North America/ATL

 

http://catchmypicture.com/CUsp8g.jpg

 

 

 

Here are post-1979 Niños:

 

http://catchmypicture.com/kfwFWP.jpg

 

 

Pre-1979 Niños:

 

http://catchmypicture.com/BCN1p5.jpg

[Jesse]

However, looks like things flip around eventually...finally a legit low frequency wave. It's been like....forever]

What does a low frequency wave entail?

[Phil]

What does a low frequency wave entail?

It's a legit, stratospherically-coupled MJO wave...not a s**ty, high-frequency CCKW playing dress up.

 

So, in this case, we should see quite the pattern progression over the next 5-8 weeks as the winter regime takes hold...though it's looking like we may see a multitude of patterns this winter due to competing Walker Cell/ENSO forcing and QBO/MJO/SAO (stratospheric/tropical-resonance) forcing.

 

If everything times right, looks a lot like a 1960s Niño, imo

[richard mann]

It's a legit, stratospherically-coupled MJO wave...not a s**ty, high-frequency CCKW playing dress up.

.. Very "colorful"

 

#chomama.

[chinook]

.. Very "colorful"#chomama.

Why stewardess I speak jive...

 

Anyhoo...nice day in the valley. A tad bit windy which amplified a wild-land fire up the road in Lafayette.

 

Waiting for my first vine ripe slicers...should be in the coming days.

[richard mann]

Why stewardess I speak jive. .....

 

Discúlpeme. ?

 

(Qué. ?)

[BLI snowman]

12z Euro and GFS look super cold. September's gonna be cold.

[TT-SEA]

12z Euro and GFS look super cold. September's gonna be cold.

 

 

12Z ECMWF looks much better for next week.   Way better than the runs yesterday.

 

http://old.ecmwf.int/products/forecasts/d/getchart/catalog/products/forecasts/medium/deterministic/msl_uv850_z500!Geopotential%20500%20hPa%20and%20Temperature%20at%20850%20hPa!216!North%20America!pop!od!oper!public_plots!2014082612!!chart.gif

 

 

Not super cold by any means... very pleasant actually.   

[Deweydog]

12Z ECMWF looks much better for next week. Way better than the runs yesterday.

 

http://old.ecmwf.int/products/forecasts/d/getchart/catalog/products/forecasts/medium/deterministic/msl_uv850_z500!Geopotential%20500%20hPa%20and%20Temperature%20at%20850%20hPa!216!North%20America!pop!od!oper!public_plots!2014082612!!chart.gif

 

 

Not super cold by any means... very pleasant actually.

[Deweydog]

12Z ECMWF looks much better for next week. Way better than the runs yesterday.

 

http://old.ecmwf.int/products/forecasts/d/getchart/catalog/products/forecasts/medium/deterministic/msl_uv850_z500!Geopotential%20500%20hPa%20and%20Temperature%20at%20850%20hPa!216!North%20America!pop!od!oper!public_plots!2014082612!!chart.gif

 

 

Not super cold by any means... very pleasant actually.

Sarcasm.

 

Euro is wrong, though.

 

#septembertoremember

[Jesse]

Sarcasm.

 

Euro is wrong, though.

 

#septembertoremember

 

Hottest ever?

[Jesse]

Euro ensembles look a little troughier than the operational in the long range.

[Jesse]

12z Euro and GFS look super cold. September's gonna be cold.

 

Do you actually believe this?

 

Would make sense after what will likely end up being a record or near-record warm July/August in many locations.

 

At very least I think the month will see a large scale pattern change. Ridging may return but it might be centered offshore more often than not, IMO.

[Jesse]

Won't lie, the 12Z runs have me pretty excited for an early taste of Fall.

 

Even if September is troughy just for the first week or so then we move into a ridgier pattern with warm days/cool nights/offshore flow I would be happy. This muggy/60+ night stuff can take an extended break, though.

 

Was browsing records last night and found out that 2013 set a new record for most 60+ lows at PDX in a calendar year. 2014 is likely right on its tail.....

 

Our summers definitely aren't getting muggier, though.

[Phil]

Not surprised at all by the troughing, as it is to be expected with the WPAC subsidence..

 

I think September will end up near average overall with some ridging returning later in the month. Large scale lift should return to the WPAC from the IO domain mid-month, marking a return to WPAC typhoon action and an amplified Rossby wave train over the NPAC with a poleward eddy flux.

 

That said, the first week or two should be troughy and crisp in the west, IMO. I could see the first 8-12 days of the month averaging well below normal

[Jesse]

Not surprised at all by the troughing, as it is to be expected with the WPAC subsidence..

 

I think September will end up near average overall with some ridging returning later in the month. Large scale lift should return to the WPAC from the IO domain mid-month, marking a return to WPAC typhoon action and an amplified Rossby wave train over the NPAC with a poleward eddy flux.

 

That said, the first week or two should be troughy and crisp in the west, IMO. I could see the first 8-12 days of the month averaging well below normal

 

Any indication that we could return to a muggier pattern later in September?

[BLI snowman]

Do you actually believe this?

 

Would make sense after what will likely end up being a record or near-record warm July/August in many locations.

 

At very least I think the month will see a large scale pattern change. Ridging may return but it might be centered offshore more often than not, IMO.

 

I'm confident that September will not be anomalously warm. I'd say average to below average is a safe bet. Pattern change is ready.

[TT-SEA]

Hopefully 2009 is still a guide right now.   Rather strong, cool trough to start September and then gorgeous for the rest of the month.   

 

That year has been a very good guide since April as I suspected.   

[BLI snowman]

Hopefully 2009 is still a guide right now.   Rather strong, cool trough to start September and then gorgeous for the rest of the month.   

 

That year has been a very good guide since April as I suspected.   

 

If you're looking at ENSO then 2009 is a terrible guide. That was a strong El Nino. This year won't be close.

[TT-SEA]

If you're looking at ENSO then 2009 is a terrible guide. That was a strong El Nino. This year won't be close.

 

ENSO has followed 2009 almost exactly so far this year... coming up from cool neutral to start the year to warm neutral by summer.   The MEI index in the summer of 2009 was around .90 and in 2014 its been around .85 which is about as close as you can get.

 

The SSTA maps from the summer of 2009 look very similar to 2014.     And my ideas on this summer going in... played out exactly as I thought.

 

Hoping to depart from 2009 in October and end up close to ENSO neutral this year.    The winter of 2009-10 was way too dreary.

 

Neutral worked great in 2013-14.   Lots of dry breaks... in fact it only rained on 50% of the days here.   

[TT-SEA]

 

http://s30.postimg.org/631tsr281/mei.png

2009	-.755	-.72	-.719	-.157	.375	.934	.949	.934	.761	1.021	1.062	1.0032010	1.148	1.517	1.386	.867	.609	-.388	-1.169	-1.846	-2.031	-1.945	-1.604	-1.5842011	-1.682	-1.565	-1.562	-1.488	-.281	-.136	-.076	-.491	-.766	-.963	-.98	-.9852012	-1.049	-.705	-.417	.061	.73	.909	1.138	.555	.268	.105	.165	.0312013	.038	-.165	-.171	.01	.108	-.242	-.436	-.614	-.19	.094	-.093	-.3122014	-.318	-.269	-.017	.152	.932	.878	.815

 

 

Yep... rising from the cold side of neutral to around .80 or .90 in the summer.      2009 and 2014 are very similar to this point.

 

I hope it drops from here... unlike 2009.

[Phil]

The tropical circulations look like a classic case of Niño/-QBO, to me. The 2009-10 analog also has those dynamics, but may ultimately fail for other reasons...in 6 weeks we should have a much better idea on where things seem to be heading, as far as the winter circulations are concerned.

[Phil]

Any indication that we could return to a muggier pattern later in September?

What would constitute a muggy pattern?

[richard mann]

Euro ensembles look a little troughier than the operational in the long range.

....  pattern later in September?

Both more near term, and through to the 5th or so of Sept., I'd say the potential is there for an increasingly more meridional type of patterning. Just how deep the main colder air element of this patterning is [although] being in question at this seasonal point looked at more in particularly where considering just how exaggerated that pattern works out to be. @

  

Beyond Sept. 3rd, my expectation is that main colder air mass will be in general recession more northward. This with some stronger movement of cold more eastward post the 5th and through to the 8th or 9th, before slacking off steadily through to 14th or so .. lending to some amount of more meridional setup, and so trough-generation. If focused progressively more northward.

 

With these ideas, where regarding later Sept., new and fresh colder air beginning - per my estimation, to spread progressively more south again, after the 16th, and if at a more stepped up pace through the 23rd of so. When a next increasingly more meridional patterning should begin. The main question at that point, being just where what "troughing" drops. .... Depth of cold, along with more general pattern evolution (shift, more longitudinal.), being the main questions here.

[TT-SEA]

The tropical circulations look like a classic case of Niño/-QBO, to me. The 2009-10 analog also has those dynamics, but may ultimately fail for other reasons...in 6 weeks we should have a much better idea on where things seem to be heading, as far as the winter circulations are concerned.

 

 

I very much doubt a 2009-10 type winter.

[Jesse]

What would constitute a muggy pattern?

 

Southerly flow.