November 2017 PNW Discussion Thread

[Phil]

Well, step one (to winter bliss) is already showing up on the long range 00z GEFS and EPS. A wave-1 -> wave-2 sudden stratospheric warming is now progged to occur the middle of December.

 

http://i724.photobucket.com/albums/ww243/phillywillie/Mobile%20Uploads/D9337414-73E9-4EC8-B589-05FC71C9A467_zpsn3we3txi.png

[Gradient Keeper]

Well, step one (to winter bliss) is already showing up on the long range 00z GEFS and EPS. A wave-1 -> wave-2 sudden stratospheric warming is now progged to occur the middle of December.

 

http://i724.photobucket.com/albums/ww243/phillywillie/Mobile%20Uploads/D9337414-73E9-4EC8-B589-05FC71C9A467_zpsn3we3txi.png

Step one? How many steps does it take? Is it a 12-step program? I'm a Snow-a-holic and I NEED MY D**n SNOW.... I'm getting withdrawal symptoms. I've been looking at Winter pics in the group and I get the shakes and jitters. WHEN !!!!

[Gradient Keeper]

Pretty big changes on 6z. Ridge through day 8 is not shoved as far east and seems to be building at 140 W. Hmmm...

 

Model comparison

 

 

Day 8 - 00z last night

http://maps1.pivotalweather.com/maps/models/gfs/2017112700/192/500h_anom.na.png

 

 

Day 8 - 6z 

http://maps1.pivotalweather.com/maps/models/gfs/2017112706/192/500h_anom.na.png

[Gradient Keeper]

Ridge just stops at 135 W. Very chilly run, especially Gorge east with a fairly deep cold pool compared to previous runs.

[Gradient Keeper]

6z GFS Extracted Data for Moses Lake. Yep, check out the extended period. That's pretty much a modified arctic air mass with highs in the 20s.

http://wxweb.meteostar.com/sample/sample.shtml?run=2017112706&text=KMWH

 

 

I wonder if there will be any improvement on the ensembles. I hope so. We'll know in 5-10 minutes.

 

[Gradient Keeper]

 

6z GFS Extracted Data for Moses Lake. Yep, check out the extended period. That's pretty much a modified arctic air mass with highs in the 20s.

http://wxweb.meteostar.com/sample/sample.shtml?run=2017112706&text=KMWH

 

 

I wonder if there will be any improvement on the ensembles. I hope so. We'll know in 5-10 minutes.

 

 

[SilverFallsAndrew]

No the ensembles are almost unanimous in showing upper level ridging in the extended. One has to wonder when this breaks down if we don't head into a roaring Pacific firehose jet situation such as in late December 2005. That is probably the best early season example of fake cold, the preceding regime in Dec. 05'. Extended periods of "fake cold" are fairly rare this early though. Usually late December into January is a better time if we are talking more than a couple days. 

[SilverFallsAndrew]

Climatologically speaking an AR situation the first or 2nd week of December would be a much better sign.

[Gradient Keeper]

Climatologically speaking an AR situation the first or 2nd week of December would be a much better sign.

Ya. The likely outcome will be a rather extensive cold pool and east winds. Still better than mild SW flow with no blocking. I think retrogression is possible, but I would lean towards the block breaking down and W-SW jet slamming us.

 

12z GFS in 3 hours 34 minutes

[SilverFallsAndrew]

Ya. The likely outcome will be a rather extensive cold pool and east winds. Still better than mild SW flow with no blocking. I think retrogression is possible, but I would lean towards the block breaking down and W-SW jet slamming us.

 

12z GFS in 3 hours 34 minutes

 

I agree with this. 

[TT-SEA]

Climatologically speaking an AR situation the first or 2nd week of December would be a much better sign.

 

I was thinking about this yesterday.    My sense is that cold and dry in the first 2 weeks of December tends to lead to another long-term rainy and warm scenario by Christmas and beyond.   Example... 2005.

[SilverFallsAndrew]

I was thinking about this yesterday.    My sense is that cold and dry in the first 2 weeks of December tends to lead to another long-term rainy and warm scenario by Christmas and beyond.   Example... 2005.

 

I think 2005 is an extreme example, but obviously I agree with your overall point. Most of the blasts in the Dec 15-25 timeframe had an early December torch. 

 

I think December 2005 is an extreme example because it was a very extended fake cold episode, almost unprecedented for early December. We won't get that cold, and it won't last as long this time. Hopefully meaning any blow torch episode to follow only lasts a week or two. Could be more similar to the slightly below normal inversion pattern we had in December 2011. 

[MossMan]

39 and mostly cloudy currently.

[Parksvillewx]

Quite frosty here this AM. 32F

[Jesse]

Snow is back in the mtntns!!

[TT-SEA]

Snow is back in the mtntns!!

 

Beautiful at Crystal Mountain this morning...

 

[SilverFallsAndrew]

Looks like the 00z is building that ridge overhead!

[Deweydog]

Looks like the 00z is building that ridge overhead!

12z too.

[wx_statman]

The dry weather being talked about for next week reminds of 2005 and 2011. Dry and chilly starts to December in a -ENSO/-QBO situation. 

[Phil]

Step one? How many steps does it take? Is it a 12-step program? I'm a Snow-a-holic and I NEED MY d**n SNOW.... I'm getting withdrawal symptoms. I've been looking at Winter pics in the group and I get the shakes and jitters. WHEN !!!!

Lmao. Actually that's step two, lol. Step one is developing the Siberian vortex to open the poleward WAFz train (already ongoing), step two is weakening the strat-PV, step three is retrograding the western ridge, step four is the the Arctic blast.

 

[Deweydog]

Lmao. Actually that's step two, lol. Step one is developing the Siberian vortex to open the poleward WAFz train (already ongoing), step two is weakening the strat-PV, step three is retrograding the western ridge, step four is the the Arctic blast.

 

So.... Wednesday? Wednesday night?

[luvssnow_spokane]

So.... Wednesday? Wednesday night?

Thursday... the 4th day of the week in the 4 step program. Remember consistency is key. 

[SilverFallsAndrew]

The dry weather being talked about for next week reminds of 2005 and 2011. Dry and chilly starts to December in a -ENSO/-QBO situation. 

 

Yeah, I guess that means a cold March is certainly on the table...

[MossMan]

I need to decide if tomorrow morning or Wednesday morning would be the better travel day over Snoqualmie Pass with a rear wheel drive van. The NWS forecast seems quite vague with “showers” and 2,500 snow levels yet the discussion says between 3-4K feet. Thoughts? Looks like it’s currently snowing pretty good up there.

[TT-SEA]

I need to decide if tomorrow morning or Wednesday morning would be the better travel day over Snoqualmie Pass with a rear wheel drive van. The NWS forecast seems quite vague with “showers” and 2,500 snow levels yet the discussion says between 3-4K feet. Thoughts? Looks like it’s currently snowing pretty good up there.

 

Neither morning looks real good.   

[MossMan]

Neither morning looks real good.

That’s what I was afraid of. Okay thanks!

[TT-SEA]

That’s what I was afraid of. Okay thanks!

 

I think maybe later Wednesday morning would be better.   Precip looks pretty spotty that morning as opposed to the solid front tomorrow.   I am just not sure if that front tomorrow is all snow at Snoqualmie Pass.

[Front Ranger]

The dry weather being talked about for next week reminds of 2005 and 2011. Dry and chilly starts to December in a -ENSO/-QBO situation. 

 

There are several other -ENSO years that had something similar around this time period, too. Including some of the main analogs I've talked about.

 

1995: Dry/chilly from 12/4 to 12/8.

1989: Dry/chilly from 12/9 to 12/18

1984: First week of the month.

1954: 11/28 to 12/3

 

1962 also had something similar a little later in the month.

[BLI snowman]

Could be a rough December for the mountains.

[Jesse]

Could be a rough December for the mountains.

Emotionally crippling at 1,600’ in particular.

[SilverFallsAndrew]

Emotionally crippling at 1,600’ in particular.

 

I'm fine. This is pretty much exactly what I predicted for December. 

[SilverFallsAndrew]

I'm fine. This is pretty much exactly what I predicted for December. 

 

On a side note 2011 is the only year I have not received accumulating snow in my 6 Decembers up here so far. 

[Front Ranger]

On a side note 2011 is the only year I have not received accumulating snow in my 6 Decembers up here so far. 

 

From what I've heard, Jan-Mar kinda made up for that....

[SilverFallsAndrew]

From what I've heard, Jan-Mar kinda made up for that....

 

In a big way. 

 

I just think people have their expectations set way to high this year.

[Front Ranger]

Pretty crazy how the 12z ensembles keep the ridge basically anchored in the same spot over Sitka from days 9-15.

[Phil]

The latest JMA/EPS/CFS weeklies are finally in agreement with regards to the retrogression in January. Some modest timing differences still, but the signal is unmistakable.

[BLI snowman]

In a big way. 

 

I just think people have their expectations set way to high this year.

 

I think we'll truthfully be lucky to see half of what we saw last winter. But it's just the nature of how things work on here,  stupidly high expectations early give way to unyielding pessimism by the time January comes around and someone has gotten "screwed". Very little even-handedness when it comes to weenie winterdom. 

[Kayla]

Pretty crazy how the 12z ensembles keep the ridge basically anchored in the same spot over Sitka from days 9-15.

 

Slightest, tiniest retro there near the end but yeah pretty impressive. At least some cold air starts to build on this side of the hemisphere late in the period.

 

#stagnant

[SilverFallsAndrew]

The 12z GFS wants to have some cold air entrenched over the middle of the country when I am there in a couple weeks. 

[Front Ranger]

In a big way. 

 

I just think people have their expectations set way to high this year.

 

Can't argue with cold, rock hard evidence.