December 2015 in the Pacific Northwest

[Front Ranger]

Some subtle difference from the GFS at hour 192, but really quite similar for 8 days out. Looking good.

 

 

[Deweydog]

Some subtle difference from the GFS at hour 192, but really quite similar for 8 days out. Looking good.

 

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Zonal flow is chicken soup for the soul.

[Gradient Keeper]

HR 192 After the initial trough slides southeast pattern resetting, new ridge building over Aleutians

[Front Ranger]

Zonal flow is chicken soup for the soul.

 

The 0z models are all showing more amplification offshore. Cool zonal but with cold air much closer than before, and would only take some minor tweaks of the pattern to produce widespread lowland snow.

[TT-SEA]

00Z ECMWF shows potential for a white Christmas here if it were to verify.  

 

http://old.ecmwf.int/products/forecasts/d/getchart/catalog/products/forecasts/medium/deterministic/msl_uv850_z500!Geopotential%20500%20hPa%20and%20Temperature%20at%20850%20hPa!240!North%20America!pop!od!oper!public_plots!2015121500!!chart.gif

[Deweydog]

The 0z models are all showing more amplification offshore. Cool zonal but with cold air much closer than before, and would only take some minor tweaks of the pattern to produce widespread lowland snow.

I think that's a bit of a stretch, but hey...

[Gradient Keeper]

Whereas it isn't all that cold, definite improvement tonight on both 00z GFS/ECMWF. Negative anomalies and arctic air building up north. -PNA takes hold, pattern flips, amplification and we turn cold/snowy! YEP

[Front Ranger]

I think that's a bit of a stretch, but hey...

 

Of course you do. Just reporting the latest, good sir. The 0z models all improved, there's no disputing that.

 

The encouraging thing for now is that we're seeing much better model agreement on the evolving pattern.

[Front Ranger]

0z GFS ensembles also improved moderately over 12z.

 

Moving in the right direction tonight, we'll see if it continues tomorrow.

[Deweydog]

Of course you do. Just reporting the latest, good sir. The 0z models all improved, there's no disputing that.

 

The encouraging thing for now is that we're seeing much better model agreement on the evolving pattern.

Shirley an improved 0z suite, in the long range, but putting out the fact a few minor tweaks and the lowlands are coated with a blanket of joy is pretty disingenuous. At best we're talking about a progressive, maritime-polar pattern without an Arctic tap.

[High Desert Mat]

Dewey, get a life. Really? All you do is try to burst bubbles and break down hopes. Funny that this is what you do for "fun". Some peoples lives.....

[Gradient Keeper]

To cut the possible tension and hostility I just wanted to announce that the 6z NAM begins in 20 minutes!

[Front Ranger]

Shirley an improved 0z suite, in the long range, but putting out the fact a few minor tweaks and the lowlands are coated with a blanket of joy is pretty disingenuous. At best we're talking about a progressive, maritime-polar pattern without an Arctic tap.

Actually, the models improved in the mid range as well.

 

I didn't say anything outrageous, or disingenuous. Widespread lowland snowfall (hint: that doesn't mean everyone sees snow) would be very possible if temps ended up slightly colder, which would only require a couple tweaks.

 

You've been quite the contrarian nitpicker lately.

[Deweydog]

Dewey, get a life. Really? All you do is try to burst bubbles and break down hopes. Funny that this is what you do for "fun". Some peoples lives.....

If you were reacting that way and it was currently snowing on the high AND low desert, you'd be totally spot on. If your life's hopes and bubbles depend on the opinions of weather novices, maybe you need to wise up a bit. I can help if you want.

[Deweydog]

Actually, the models improved in the mid range as well.

 

I didn't say anything outrageous, or disingenuous. Widespread lowland snowfall (hint: that doesn't mean everyone sees snow) would be very possible if temps ended up slightly colder, which would only require a couple tweaks.

 

You've been quite the contrarian nitpicker lately.

I guess we'll see how close we end up in a few days and find out just how nitpicky and contrarian I've been. Generally I pick my nit spots pretty well. I think it's a bit above and beyond to look at the upcoming (7-10 days) pattern and see a widespread lowland snow/verge of pattern in the works. Requires quite a bit of creativity. Widespread 1,000 foot snow levels is another story...

[Front Ranger]

I guess we'll see how close we end up in a few days and find out just how nitpicky and contrarian I've been. Generally I pick my nit spots pretty well. I think it's a bit above and beyond to look at the upcoming (7-10 days) pattern and see a widespread lowland snow/verge of pattern in the works. Requires quite a bit of creativity. Widespread 1,000 foot snow levels is another story...

How things end up down the road has no bearing on this. It has nothing to do with your picking of nits.

 

I'm not predicting anything. The fact that you're acknowledging widespread 1,000' snow levels agrees with my point: the pattern as depicted is close to supporting very low snow levels.

 

There are enough legitimate disagreements on here without fabricated ones like this. Don't be lame. Just enjoy the ride like everyone else, and leave the condescension behind.

[BLI snowman]

To cut the possible tension and hostility I just wanted to announce that the 6z NAM begins in 20 minutes!

 

Lots of lives depend on the model rides. It's a touch and go situation for many. Deadly serious.

[BLI snowman]

If nothing else that's going to be one helluva SE ridge towards Christmas. That's always a good start. Probably will be all kinds of severe weather somewhere with that airmass.

[Deweydog]

How things end up down the road has no bearing on this. It has nothing to do with your picking of nits.

 

I'm not predicting anything. The fact that you're acknowledging widespread 1,000' snow levels agrees with my point: the pattern as depicted is close to supporting very low snow levels.

 

There are enough legitimate disagreements on here without fabricated ones like this. Don't be lame. Just enjoy the ride like everyone else, and leave the condescension behind.

You know just as well as I do there are very big differences between a pattern which supports widespread lowland snow and one which supports 1,000 foot snow levels. Don't be a boob just for the sake of drawing this out.

[Front Ranger]

Lots of lives depend on the model rides. It's a touch and go situation for many. Deadly serious.

Model riding often ends up like Final Destination 3 around here.

[Gradient Keeper]

*.*.*.*.*.*.*.*.*.*.*.*.*.*.*.*.*.*.*.*.*.*.*.*.*
*.*.*. MERRY CHRISTMAS .*.*.*
[Model Countdown] 12/15/15
Next up................
*6z GFS in 1 hour 26 minutes
12z GFS in 7 hours 26 minutes
12z GEM in 8 hours 24 minutes
12z ECMWF in 9 hours 49 minutes
I added the Merry Christmas thingy because well, it's 10 days until Christmas, and because I did it last year....AND because 'Merica.

[Front Ranger]

You know just as well as I do there are very big differences between a pattern which supports widespread lowland snow and one which supports 1,000 foot snow levels. Don't be a boob just for the sake of drawing this out.

Maybe you are interpreting widespread lowland snow differently than me. January 2002 produced widespread lowland snow. A lot of places in the lowlands saw snow. But not everyone!

 

Do you think there is a huge difference between what the 0z GFS showed and January 2002?

[Bryant]

Shirley an improved 0z suite, in the long range, but putting out the fact a few minor tweaks and the lowlands are coated with a blanket of joy is pretty disingenuous. At best we're talking about a progressive, maritime-polar pattern without an Arctic tap.

Honestly I'm with you here. If it hasn't proven itself already, the pattern is very progressive and shows no signs of changing. While the +PV wants to speed up the pattern, the tropical forcings want to slow it down. We may get lucky and see some snow, which would be more than I saw all last winter, but it's going to come with a very borderline pattern if it does at all. We're limited in time here, and in my opinion, once this temporary forcing shifts out of the Maritime region and back to the dateline, the Aleutian low and Pacific jet extension will return.

 

Given what I've learned from Phil (who's been a huge help), once we shift back into an Aluetian low pattern, it's only a matter of time until we see some solid wave 1 displacment of the PV leading to a full blown SSW. This is via mass transport and wave bombardment on the PV due the domain locations of the Aleutian low / Eurasia high. Only issue is, once the PV is broken down and cold air is available, seasonal forcings will shift in favor of the East coast, throwing a ridge over the West.

[Deweydog]

Maybe you are interpreting widespread lowland snow differently than me. January 2002 produced widespread lowland snow. A lot of places in the lowlands saw snow. But not everyone!

 

Do you think there is a huge difference between what the 0z GFS showed and January 2002?

One, two, three, four I declare a semantic war! When you say something like that here you know how it's gonna be interpreted. If favored CZ areas see a little something or Whatcom County perhaps I would hardly consider that widespread. There's a reason why those areas are considered a different breed on a microscale level.

[Front Ranger]

Honestly I'm with you here. If it hasn't proven itself already, the pattern is very progressive and shows no signs of changing. While the +PV wants to speed up the pattern, the tropical forcings want to slow it down. We may get lucky and see some snow, which would be more than I saw all last winter, but it's going to come with a very borderline pattern if it does at all. We're limited in time here, and in my opinion, once this temporary forcing shifts out of the Maritime region and back to the dateline, the Aleutian low and Pacific jet extension will return.

 

Given what I've learned from Phil (who's been a huge help), once we shift back into an Aluetian low pattern, it's only a matter of time until we see some solid wave 1 displacment of the PV leading to a full blown SSW. This is via mass transport and wave bombardment on the PV due the domain locations of the Aleutian low / Eurasia high. Only issue is, once the PV is broken down and cold air is available, seasonal forcings will shift in favor of the East coast, throwing a ridge over the West.

Things may or may not evolve like 2006-07, but if they do, keep in mind that these things take time and cold air can become available long before the PV breaks down, which happened for the West that winter.

 

Also, there's more than one way to skin a cat.

[Front Ranger]

One, two, three, four I declare a semantic war! When you say something like that here you know how it's gonna be interpreted. If favored CZ areas see a little something or Whatcom County perhaps I would hardly consider that widespread. There's a reason why those areas are considered a different breed on a microscale level.

That's not what happened in January 2002. Way to avoid the question (insert lawyer joke here).

[BLI snowman]

Maybe you are interpreting widespread lowland snow differently than me. January 2002 produced widespread lowland snow. A lot of places in the lowlands saw snow. But not everyone!

 

Do you think there is a huge difference between what the 0z GFS showed and January 2002?

 

FYI, everyone actually did see snow in January 2002 in western OR and western WA. Some places right at sea level probably didn't get more than 1/2" or so accumulation but everyone did have multiple periods of snow in the air.

[Bryant]

Things may or may not evolve like 2006-07, but if they do, keep in mind that these things take time and cold air can become available long before the PV breaks down, which happened for the West that winter.

 

Also, there's more than one way to skin a cat.

http://0.media.collegehumor.cvcdn.com/76/47/adb2e1eb2a215032c04621db1723ae51.jpg

[Deweydog]

That's not what happened in January 2002. Way to avoid the question (insert lawyer joke here).

 

Are you really seeing a January 2002 repeat here?  The references to the CZ and Whatcom County are to what MAY happen over the next 7-10 days in what would be considered a 1,000 foot snow level pattern.  

 

January 2002 featured an extremely robust hybrid trough with a significant Arctic tap (-30c into eastern Alberta) and a fairly well-established quasi-block.  Unless you're being creative about the lay of things right now, there's nothing like that on the horizon.  Progressive with minor tweaks to how far into 520's thicknesses may sneak is the screaming message at the moment.  

 

Now if you want to talk about a strictly onshore flow setup, look at March 2006.  Of course, again, there's no indication of a monster like that.  Pretty freakin' rare...

[BLI snowman]

December 23-25 has some potential for a cold core shower setup, albeit with an inconsistent signal, but otherwise there's not a lowland snow threat anywhere in sight. 

 

Even the simplest of weenies can tell you the real main ingredient in getting lowland snow is offshore or dead gradients and I don't see much potential for either in the current model range. 

 

Shame too because late December is the season for scoring snow with wimpy offshore flow setups (see 12/29/2009 or 12/22/1997). 

[Front Ranger]

FYI, everyone actually did see snow in January 2002 in western OR and western WA. Some places right at sea level probably didn't get more than 1/2" or so accumulation but everyone did have multiple periods of snow in the air.

Literally everyone, huh?

 

Well, according to Dewey one must specify the exact nature of such terms as "widespread", "lowlands", and "snow". Does the phrase widespread lowland snow mean 75% of the population below 700' saw accumulating snow, or does it mean 90% saw some snow-like substance in the air?

 

These are the questions we must answer.

[Deweydog]

Literally everyone, huh?

 

Well, according to Dewey one must specify the exact nature of such terms as "widespread", "lowlands", and "snow". Does the phrase widespread lowland snow mean 75% of the population below 700' saw accumulating snow, or does it mean 90% saw some snow-like substance in the air?

 

These are the questions we must answer.

 

Bottom line is the first post I responded to was misleading to the masses here.  There is no legitimate threat or even a minor-tweak worthy pattern at this point for anyone below 1,000 feet or in heavily favored areas below, IMO.  The enraged response by the desert door mat was a pretty good indication of the fact there's been a little too much hand-wringing compared to what the current/upcoming pattern is probably worth.  It may be a tough pill for some to swallow, but embellishment, semantic laden as you may find it, doesn't help.  

 

Obviously we could wake up tomorrow to a new model world filled with 150w blocks and Vancouver Island surface lows crashing down the coast, but we'll just have to jump off that bridge when we come to it.

[Front Ranger]

The 0z models are all showing more amplification offshore. Cool zonal but with cold air much closer than before, and would only take some minor tweaks of the pattern to produce widespread lowland snow.

 

Are you really seeing a January 2002 repeat here?  

 

Nope. Already said what I'm seeing here.

 

Jan 2002 was a cold maritime air mass. It produced widespread lowland snow, and I think the pattern depicted would only need a few tweaks to produce something similar. Pretty simple, or to put it in a the typical, condescending Dewey way, it's not rocket science. 

[Front Ranger]

Bottom line is the first post I responded to was misleading to the masses here.  There is no legitimate threat or even a minor-tweak worthy pattern at this point for anyone below 1,000 feet or in heavily favored areas below, IMO.  The enraged response by the desert door mat was a pretty good indication of the fact there's been a little too much hand-wringing compared to what the current/upcoming pattern is probably worth.  It may be a tough pill for some to swallow, but embellishment, semantic laden as you may find it, doesn't help.  

 

 

Yes, don't look inward, look outward. That's always the answer.

[BLI snowman]

Literally everyone, huh?

 

Well, according to Dewey one must specify the exact nature of such terms as "widespread", "lowlands", and "snow". Does the phrase widespread lowland snow mean 75% of the population below 700' saw accumulating snow, or does it mean 90% saw some snow-like substance in the air?

 

These are the questions we must answer.

 

I'm pretty sure that PuyallupJon might have missed out on that trough, but the rest were blessed. 

[Deweydog]

Nope. Already said what I'm seeing here.

 

Jan 2002 was a cold maritime air mass. It produced widespread lowland snow, and I think the pattern depicted would only need a few tweaks to produce something similar. Pretty simple, or to put it in a the typical, condescending Dewey way, it's not rocket science. 

 

If you don't see the differences, both synoptic and mircoscale, I'm not sure what else to tell you.  Obviously there's always a chance things could go crazy between now and then but it's gonna take more than minor tweaks, Tweak.  

[Deweydog]

Well the 6z NAM says no snow for the lowlands through Friday morning, even with its raging cold bias.  

[Gradient Keeper]

Lots of lives depend on the model rides. It's a touch and go situation for many. Deadly serious.

This is very true, and admittedly, I too once suffered from the angst of model riding always at the end of my seat, chair, recliner, toilet(What? No one else has ever done this? You're not a real model rider until you've done so anxiously while sitting precariously on the porcelain throne.) BUT now it is no longer a life and death issue for me. I did one time though jump off the cliff in my backyard when the GFS pulled the rug out from under us within 72 hours of a "solid lock" for an arctic blast, but it's only a 2' drop, so I couldn't even manage a sprained ankle. I did roll around pretending I was in agony though. 6z GFS is running!

[Timmy]

06z shows snow at hr 252 (Christmas) to the valley floor.

[Gradient Keeper]

06z shows snow at hr 252 (Christmas) to the valley floor.

Well, through day 7 it was a touch milder, but then..... AND THEN....

I noticed the 2nd ridge after day 9 is more amplified, not enough for a blast, but cold northerly flow as the ridge "stands up" better even as it's being shoved eastward. The result is we may lose the milder pacific surface flow with W-SW winds and northerly flow is present. *After day 10 - Christmas Eve-Christmas Day a weak low moves down from near Vancouver Island. There is not a lot of moisture, but some especially Coast Range west to the beaches. Thicknesses fall to 520-522, 850mb -8c with moisture and light winds. This very well could bring snow levels down to the valley floor, if not sticking at 500'. IF the ridge amplifies a bit further, or rather we see a trend for it to do so, then snow could be more likely everywhere. Unfortunately the pattern is shown to be far too progressive still. Stay tuned! Onto 12z!