September 2016 Observations and Model Discussion for the Pacific Northwest

[Phil]

So we want a warm west and a cold east for SON?

I wouldn't necessarily say that.

 

If you're looking for clues in the pattern itself, the strongest correlation to "failed" Niña winters is actually zonal flow over North America in October/November (high Z/M ratio) while the strongest correlation to "successful" Niña winters is a vortex to the East of Greenland in October.

 

None of these are perfect predictors, however.

[Front Ranger]

How does the start of this September compare to the start of September 2015 down your way. We are running 2F warmer and much drier than last year.

 

Most places are still running -2 to -3 below normal for the month.

[Front Ranger]

5 times as much rain last year at my location... 5 inches vs just over 1 inch.   

 

And it was colder.   

 

2015 had a significant warm period the 9th - 12th. This year will feature a cool clipper. As a result, 2016 will end up cooler through the 13th, at least.

[Front Ranger]

There's a bit more humidity today than I figured there would be; currently sitting at 71F / 61F dewpoint with mostly sunny skies and very little wind. It's about as close to being perfectly comfortable as it gets. Tomorrow will be interesting, the upper level pattern looks cold but the outflow starts early and most sunny summer days without a sea breeze end up above average.

 

Tomorrow will definitely not be above normal most places.

[Front Ranger]

The city of North Bend must be thinking a snowy winter... they took down all the summer banners this week with people rafting and rock climbing and put up the winter banners with people skiing.   Normally they put up fall banners and then the winter ones in November.  

 

 

Budget cuts.

[VancouverIslandSouth]

This is pretty late though.  I find it nearly impossible you could end up above normal tomorrow, but then again this year has had some weird surprises. 

 

Yeah, I doubt it will be the case everywhere, or even across the Saanich Peninsula but the wind direction can overcome seemingly unfavorable upper level conditions when it induces down sloping/suppresses the sea breeze. Up to 76F here today in a pocket of warmth, while YYJ a bit to the north is sitting at 66F and the harbor a bit to the south is sitting at 68F.

[Front Ranger]

You mean like someone saying that it was highly probable that Seattle had seen its majority of 80 degree highs for the year at the end of June. 

 

Yes, that was not a smart call either.

[TT-SEA]

Tomorrow will definitely not be above normal most places.

 

 

65 at SEA tomorrow.

[VancouverIslandSouth]

2006-2014 had: Nov 2006, Jan 2007, epic snowfall above 1000' in 2007-08 (the east side did amazing), Dec 2008, multiple other snow events in early 2009, Dec 2009, Nov 2010/Feb 2011 (both top tier arctic outbreaks for when they occurred), Jan 2012, Dec 2013, and Feb 2014. 

 

It actually was not a bad stretch at all. It was only missing a big Arctic event in January, but it performed big time in every other way. It was followed up by a 2 year terrible stretch.

 

Aside from a small part of SE Vancouver Island that got dumped on with heavy wet snow late Feb 2014, that doesn't apply to much of Northern WA / SW BC. January 2012 was the last one that saw widespread snow up this way and even then a few areas missed out (I don't think YVR did very well with that or any winter that followed). The terrible stretch started over 4 years ago up this way.

[Front Ranger]

Aside from a small part of SE Vancouver Island that got dumped on with heavy wet snow late Feb 2014, that doesn't apply to much of Northern WA / SW BC. January 2012 was the last one that saw widespread snow up this way and even then a few areas missed out (I don't think YVR did very well with that or any winter that followed). The terrible stretch started over 4 years ago up this way.

 

Obviously, not all of those events delivered significant snowfall everywhere. But they were Arctic events and/or major snowfalls. Not a bad stretch for the PNW overall.

[snow_wizard]

I wouldn't necessarily say that.

 

If you're looking for clues in the pattern itself, the strongest correlation to "failed" Niña winters is actually zonal flow over North America in October/November (high Z/M ratio) while the strongest correlation to "successful" Niña winters is a vortex to the East of Greenland in October.

 

None of these are perfect predictors, however.

 

It appears the big thing we want is above normal heights centered over the Bering Sea.  That has been a very dominant feature this summer.  We will see if it continues.

[snow_wizard]

Obviously, not all of those events delivered significant snowfall everywhere. But they were Arctic events and/or major snowfalls. Not a bad stretch for the PNW overall.

 

Except for the lack of snow since 2012.  We are in a terrible snow drought here.  One of the worst on record in fact.  No doubt we have done much better getting cold air.

[BLI snowman]

Obviously, not all of those events delivered significant snowfall everywhere. But they were Arctic events and/or major snowfalls. Not a bad stretch for the PNW overall.

3 of the last 4 winters have been virtually snowless across the entire region. That is a bad stretch.

[Front Ranger]

3 of the last 4 winters have been virtually snowless across the entire region. That is a bad stretch.

I said it's been terrible since 2014. But 2013-14 was a very good winter for OR, and that does count for something.

[BLI snowman]

I said it's been terrible since 2014. But 2013-14 was a very good winter for OR, and that does count for something.

 

3/4 is 3/4. It's fair to say it's been a lame stretch recently overall. 

[Front Ranger]

3/4 is 3/4. It's fair to say it's been a lame stretch recently overall.

Also fair to say 2006-2014 was not a bad stretch at all, which was my point.

[BLI snowman]

Also fair to say 2006-2014 was not a bad stretch at all, which was my point.

 

Not the best modern multi-year stretch, and obviously not the worst. I would take 1988-89 to 1998-99 over it, at least for the Portland area.  Only one true stinker in that stretch here. 

[Front Ranger]

Not the best modern multi-year stretch, and obviously not the worst. I would take 1988-89 to 1998-99 over it, at least for the Portland area. Only one true stinker in that stretch here.

1991-92 was worse than any winter 2006-14, though. For the PNW overall. And 1993-94 was pretty bad outside of a largely snowless modified Arctic event in November that fell short of both Nov 2006 and Nov 2010. I'd put it on the same level as 2012-13, the worst winter in the 2006-14 stretch.

 

Additionally, 2008-09 was a better winter for the PNW overall than any winter in that ten year period. Yes, 1992-93 was better for the Willamette Valley, but not that great for a big part of western WA.

[stuffradio]

I loved that snow event in late Nov 2006. I got about 1-1.5 feet from that.

[Abbotsford_wx]

It's been pretty much the worst ever up here no matter how you slice the data...

 

Worst four year period on recond

Worst five year period on record

Worst six year period on record

Worst seven year period on record

Worst eight year period on record

 

It only becomes second worst when you reach nine years. (For the curious, the worst 9 year period was 1997 to 2005.)

[Front Ranger]

It's been pretty much the worst ever up here no matter how you slice the data...

 

Worst four year period on recond

Worst five year period on record

Worst six year period on record

Worst seven year period on record

Worst eight year period on record

 

It only becomes second worst when you reach nine years. (For the curious, the worst 9 year period was 1997 to 2005.)

Based on just snowfall, I assume.

[BLI snowman]

1991-92 was worse than any winter 2006-14, though. For the PNW overall. And 1993-94 was pretty bad outside of a largely snowless modified Arctic event in November that fell short of both Nov 2006 and Nov 2010. I'd put it on the same level as 2012-13, the worst winter in the 2006-14 stretch.

 

Additionally, 2008-09 was a better winter for the PNW overall than any winter in that ten year period. Yes, 1992-93 was better for the Willamette Valley, but not that great for a big part of western WA.

 

For SW WA, 1991-92 was the worst winter of the bunch and 2008-09 was the best.

 

But the former period was much more consistent overall here. 1993-94 sucked for most of the region but February 1994 delivered a heavy wet snowfall for SW WA late in the month. And then 1988-89, 1989-90, 1992-93, 1994-95, 1995-96, and 1997-98 all had significant (6"+) snowstorms here. 1996-97 had some snow/ice, and 1990-91 and 1998-99 both had major cold spells that surpass anything we've seen since in terms of intensity. That made for 10/11 years with some winter weather event of significance here (heavy snow, arctic airmass, or ice storm or some combination of those). That's a nice track record by modern day standards.

[Abbotsford_wx]

Based on just snowfall, I assume.

 

Yeah. I didn't look at temperature. That would be harder to quantify.

[Front Ranger]

For SW WA, 1991-92 was the worst winter of the bunch and 2008-09 was the best.

 

But the former period was much more consistent overall here. 1993-94 sucked for most of the region but February 1994 delivered a heavy wet snowfall for SW WA late in the month. And then 1988-89, 1989-90, 1992-93, 1994-95, 1995-96, and 1997-98 all had significant (6"+) snowstorms here. 1996-97 had some snow/ice, and 1990-91 and 1998-99 both had major cold spells that surpass anything we've seen since in terms of intensity. That made for 10/11 years with some winter weather event of significance here (heavy snow, arctic airmass, or ice storm or some combination of those). That's a nice track record by modern day standards.

 

Yeah, it definitely varies by location. In Tacoma, where I grew up for the most part...

 

1988-89: Very good winter

1989-90: Decent thanks to one snow event

1990-91: Very good, though not as good as further north

1991-92: Terrible

1992-93: Ok, but no true Arctic air or major snowstorms (a couple 2-3")

1993-94: Terrible aside from modified Arctic event with just a dusting of snowfall in November

1994-95: Ok, thanks to a 4-5" snowstorm in early December

1995-96: Good 

1996-97: Good, though we missed out on the huge snows Seattle north had (about 12-13" total in December, so still good)

1997-98: Decent, thanks to big snowstorm in January

1998-99: Ok, thanks to major Arctic blast in December with a little snow, and a little snow in February

 

More recently

 

2006-07: Good

2007-08: Ok, a few small snow events

2008-09: Very good

2009-10: Ok, due to Arctic event and small snowfall in December

2010-11: Good, two major Arctic events and decent snow

2011-12: Good, major snow/ice storm in January

2012-13: Bad, just modified Arctic event in January with a little snow

2013-14: Decent thanks to two Arctic events, but very little snow

 

If 2013-14 had just managed to deliver a significant snowfall or two, it would have been probably the best 8 year stretch since at least 1983-91.

 

EDIT: If I go back to 2005-14 in Tacoma, it was actually a decent 9 year stretch, since Dec 2005 had a significant snowstorm (6") and the Arctic windstorm event in February.

[snow_wizard]

The 18z GFS is really getting aggressive with the trough for next Sunday.  Thicknesses drop to about 543 over SEA.

 

Tomorrow's trough is also getting colder in the home stretch.  The 546 thickness line now drops to Everett.

[TT-SEA]

The 18z GFS is really getting aggressive with the trough for next Sunday.  Thicknesses drop to about 543 over SEA.

 

Tomorrow's trough is also getting colder in the home stretch.  The 546 thickness line now drops to Everett.

 

 

 

 

Here is the 12Z ECMWF for next Sunday.    

 

http://stream.ecmwf.int/data/atls04/data/data01/scratch/ps2png-atls04-95e2cf679cd58ee9b4db4dd119a05a8d-SJt6k4.png

[snow_wizard]

Mark Nelson's two weeks of warm bliss is in serious trouble it would appear.

 

Amazing how it just keeps getting watered down.

 

[Front Ranger]

No doubt that the trend the past couple weeks has been to push back and weaken warm weather.

[snow_wizard]

For SW WA, 1991-92 was the worst winter of the bunch and 2008-09 was the best.

 

But the former period was much more consistent overall here. 1993-94 sucked for most of the region but February 1994 delivered a heavy wet snowfall for SW WA late in the month. And then 1988-89, 1989-90, 1992-93, 1994-95, 1995-96, and 1997-98 all had significant (6"+) snowstorms here. 1996-97 had some snow/ice, and 1990-91 and 1998-99 both had major cold spells that surpass anything we've seen since in terms of intensity. That made for 10/11 years with some winter weather event of significance here (heavy snow, arctic airmass, or ice storm or some combination of those). That's a nice track record by modern day standards.

 

Some places had a nice cold / snow event in Nov 1993.  In fact where I was living in Woodinville it snowed and then got cold and clear for a while.

[snow_wizard]

No doubt that the trend the past couple weeks has been to push back and weaken warm weather.

 

To me that says we have turned the corner more than anything.  The exact opposite had been the case for a long time.

[TT-SEA]

Mark Nelson's two weeks of warm bliss is in serious trouble it would appear.

 

Amazing how it just keeps getting watered down.

 

http://old.wetterzentrale.de/pics/MT8_Seattle_USA_ens.png

 

 

Its NELSEN.

 

And the mean is above normal most of the run.   And its the 18Z GFS.    

 

All he said it that it would be nice with no extreme heat and very little rain.

 

Weren't you all excited about a cold August at the start of the month?   Your cold bliss got in serious trouble fast.   You must have egg on your face huh?   

 

Just repeating what you have said about Mark in the last 24 hours.   

[snow_wizard]

Its NELSEN.

 

And the mean is above normal most of the run.   And its the 18Z GFS.    

 

All he said it that it would be nice with no extreme heat and very little rain.

 

Weren't you all excited about a cold August at the start of the month?   Your cold bliss got in serious trouble fast.   You must have egg on your face huh?   

 

Just repeating what you have said about Mark in the last 24 hours.   

 

No doubt I got egg in my face in August.

[TT-SEA]

No doubt I got egg in my face in August.

 

 

Well... at least you can turn your old timer sayings around on yourself.  

 

Nature will always make fools of anyone trying to predict what she will do!  

[Deweydog]

PDX was a day early.  

[TT-SEA]

PDX was a day early.  

 

 

Last weekend I said the ECMWF showed 80 on both Friday and Saturday for PDX.    You asked if we were going to do this again?  

 

Actual results came in at 84 and 86.

 

This little warm up did not fizzle in the home stretch.   

[Deweydog]

Last weekend I said the ECMWF showed 80 on both Friday and Saturday for PDX.    You asked if we were going to do this again?  

 

Actual results came in at 84 and 86.

 

This little warm up did not fizzle in the home stretch.   

 

You're the only true voice of forecasting reason around here.  What a burden that must be.  

 

I suppose I'd better be prepared for that 95 next Saturday.  We have a doubleheader!  

[TT-SEA]

You're the only true voice of forecasting reason around here.  What a burden that must be.  

 

I suppose I'd better be prepared for that 95 next Saturday.  We have a doubleheader!  

 

 

Hardly.   And I was just reporting what the ECMWF showed.   Not making a forecast.   

 

12Z ECMWF still shows upper 80s and low 90s for next Saturday.  

[Front Ranger]

Its NELSEN.

 

And the mean is above normal most of the run. And its the 18Z GFS.

 

All he said it that it would be nice with no extreme heat and very little rain.

He said warm, with no below normal temps. Never a good idea for a 2 week period.

 

Doesn't he read this forum??

[Deweydog]

Hardly.   And I was just reporting what the ECMWF showed.   Not making a forecast.   

 

12Z ECMWF still shows upper 80s and low 90s for next Saturday.  

 

Not much in the way of offshore flow.  It'll be tough even if the warmer runs prove correct, which I suspect won't be the case.  Could be some upsettingly mild nights coming up, though.  That'll keep you happy.  

[VancouverIslandSouth]

Clouds were entering the Juan de Fuca most of the day (looking southwest over downtown Victoria):

 

http://i131.photobucket.com/albums/p286/jemeric/IMG_3637_zps4dpnzq4p.jpg

 

And breaking up as they hit the head of the Puget Sound (looking southeast over Oak Bay):

 

http://i131.photobucket.com/albums/p286/jemeric/IMG_3643_zpsowcc6nh5.jpg