November 2017 PNW Discussion Thread

[Front Ranger]

I'm not seeing a 2007 like outcome.  This year is much more blocky.

 

I agree. Doesn't mean it should be completely disregarded as an analog, though. I think we have to look at analogs as a blend of likely possibilities, varying outcomes that still produce a coherent signal.

[Jesse]

The mountain snowpack, at least in Oregon, has been completely destroyed. I'm pretty sure there are no survivors.

I did a webcam tour and was actually surprised how much remains above 4,000’ or so. The fact that we didn’t get a ton of rain when temperatures were the warmest helped.

[Dave]

I did a webcam tour and was actually surprised how much remains above 4,000’ or so. The fact that we didn’t get a ton of rain when temperatures were the warmest helped.

Looking at the tripcheck cams, it is pretty bleak at the pass levels.  Santiam had 30" just last week.  It's pretty spotty now.  Unfortunate, but common in November.

[Gradient Keeper]

12z re-cap
CMC, ECMWF, GEM (Images posted in that order)

 

Centered at day 8(FCST HR 192)

 

Viewing all 3 Operational runs the GFS was certainly the most progressive with the ridge tending to be shoved eastward broadening out/flattening and thus not setting up in a favorably. GFS also lacks any amplification and features above normal heights/ridge over the southern rockies. Perhaps resulting in more of a "fake cold" pattern.

 

CMC and ECMWF are in quite good agreement days 5-8 with cold trough digging southward over WA/OR and above normal heights/ridge over southern plains. Much better teleconnection pattern also. Both models suggest possible arctic air, but the amplification needed is lacking, for now. Anytime in late November through the heart of Winter we see the ridge axis around 150-160 W at the very least it is encouraging. We need that if we have any shot at cold, arctic air.

 

http://maps3.pivotalweather.com/maps/models/ggem/2017112412/192/500h_anom.na.png

 

 

http://maps1.pivotalweather.com/maps/models/ecmwf/2017112412/192/500h_anom.na.png

 

http://maps1.pivotalweather.com/maps/models/gfs/2017112412/192/500h_anom.na.png

 

 

12z Ensembles - 500mb

12z GEFS flow is simply too progressive. Chilly NW flow at times. Ridging is transitory and very flat after day 7. Extended period is not in agreement with CMC/ECMWF.

 

12z CMCE. Too progressive. Block is initially 150-140 W, builds closer to the Coast after day 8-10. Above normal heights over us. Fake cold pattern potentially. Not an arctic pattern.

 

12z EPS less progressive. Block sets up 160-150 W, then edges towards 145-140 W and remains there through day 8-10. Definitely seeing a bit better amplification, but ridge axis just a bit too close. Chilly NW to perhaps N flow at times. Potential is there for improvement. Possible backdoor intrusion of cold air into eastern Washington/Columbia Basin.

[Jesse]

Looking at the tripcheck cams, it is pretty bleak at the pass levels.  Santiam had 30" just last week.  It's pretty spotty now.  Unfortunate, but common in November.

 

The Mt. Hood sno-tel site (5,400') still is reporting over a foot on the ground. Granted they had well over 30" just a few days ago. But it isn't completely gone.

[Front Ranger]

Looking at the tripcheck cams, it is pretty bleak at the pass levels.  Santiam had 30" just last week.  It's pretty spotty now.  Unfortunate, but common in November.

 

Yeah, mid Dec-Mar is really the key period for building snow pack. Not that good snowpack can't be built earlier, it's just much more likely to survive into the spring later.

 

DJ droppin-inspired new name?

[Phil]

Good call. It's obvious there will be a cold snap of some sort during week 2.

 

It should be noted December 1970 was pretty cold and snowy for many though.

I also think there should be a (brief) troughy episode in early December as a Rossby wave packet rides through, but I think overall the month will run well above average.

 

I'm very excited for you guys January, though. I might even find an excuse to visit my extended family in Everett, if it starts to look like a slam dunk.

[Phil]

This would fit with most leading analogs featuring a generally warm West in December. Of course, this doesn't mean wall to wall warmth in December, as discussed in the Winter Predictions thread the past couple weeks. Some of these years had cool spells with some snow.

 

post-949-0-15240400-1510796688.png

Fascinating.

 

I know it's subjective, but to me this really feels like an old timer's Niña. At least in terms of the pattern progression. Haven't seen an east-based Walker Cell/IPWP under a +SIOD/-QBO since the 1950s. Throw in weakening solar, and you have a recipe for some interesting stuff centered in the mid-winter period.

[Phil]

I wondering if you realize almost none of your analogs line up with what the NE Pacific looked like in Oct-Nov. I think that stubborn positive height / pressure anom out there is key to this winter. Past history is adamant the persistent positive anoms out there are a big deal.

Remember, though, that there was a well-timed MJO wave in tandem with that residual warm pool/off-equator forcing that really enhanced that GOA ridge last month.

 

I'm not confident it was a background state at the time, though I'm assuming it will indeed become a background state sometime this winter.

[Jesse]

Fascinating.

 

I know it's subjective, but to me this really feels like an old timer's Niña. At least in terms of the pattern progression. Haven't seen an east-based Walker Cell/IPWP under a +SIOD/-QBO since the 1950s. Throw in weakening solar, and you have a recipe for some interesting stuff centered in the mid-winter period.

The Thanksgiving blowtorch out here is actually pretty textbook for an "old school" type of Niña.

[Phil]

As far as climate is concerned, I'm very happy to see the -NAM return. Tropical convection is finally strengthening and consolidating equatorward as a result (this following the prolonged anemic state that had dominated since 2013).

 

http://i724.photobucket.com/albums/ww243/phillywillie/Mobile%20Uploads/6D00B48D-F3D8-4297-8C25-35D655B0AD1C_zps9cgd7hym.jpg

 

The resulting increase in cloud cover and wind speeds (between 30N - 30S) is just beginning to draw down OHC within those latitudes, through a combination of evaporative cooling (extraction and transfer latent heat, which is released via condensation in convection) and reduced insolation.

[Jesse]

Another super torchy day. What a disappointment.

[TigerWoodsLibido]

Another super torchy day. What a disappointment.

But beautiful here. Put up the Christmas lights outside. Nicest Black Friday for me since 2008

[Jesse]

But beautiful here. Put up the Christmas lights outside. Nicest Black Friday for me since 2008

 

What if this is a trend for the rest of the winter though

[WeatherArchive]

What if this is a trend for the rest of the winter though

Welcome to climate change. Like it?   

[Jesse]

Welcome to climate change. Like it?   

 

If it gives us more January supercells I'm all for it.

[WeatherArchive]

When does fake cold become real?

When mankind stops polluting into the air and oceans.

[Timmy]

What if this is a trend for the rest of the winter though

What if it isn’t through ?

[Jesse]

What if it isn’t through ?

Then it must dead end somewhere.

[seattleweatherguy]

The ensemble spread is large, but there are some truly insane members in there, along with many that resemble December 2008 or November 2010. A smaller cluster has the ridge closer to the coast, but that looks like a product of a delayed retrogression and stronger PV, rather than a denied one.

How insane are we talking? And if the ridge is closer wouldn't it cause temp to be warmer vs of it was more offshore?

[umadbro]

How insane are we talking? And if the ridge is closer wouldn't it cause temp to be warmer vs of it was more offshore?

Depends on which side of it You're on.

[Deweydog]

How insane are we talking? And if the ridge is closer wouldn't it cause temp to be warmer vs of it was more offshore?

All signs point to an insanity level in the 6.6 to 6.9 range on the Gifford-Pinchot-Bachman-Turner-Overdrive Insanity Scale (GPBTOIS).

[SilverFallsAndrew]

Another super torchy day. What a disappointment.

 

Beautiful day. Not sure how anyone could be disappointed.

[SilverFallsAndrew]

I did a webcam tour and was actually surprised how much remains above 4,000’ or so. The fact that we didn’t get a ton of rain when temperatures were the warmest helped.

 

WHAT?! I had about 3.5" of rain the 20-23rd with temps mostly in the 50s at 1600'....Pass elevations probably got at least that much rain if not more. 

[Deweydog]

Beautiful day. Not sure how anyone could be disappointed.

I sobbed uncontrollably while hanging lights in the face of slightly mild sunshine.

[SilverFallsAndrew]

I sobbed uncontrollably while hanging lights in the face of slightly mild sunshine.

 

Here at Oregon's Station of the God's it is going to end up with something around a 55/35 day. Not exactly a "torch" in the south valley. Just a few degrees above average. 

[Jesse]

Beautiful day. Not sure how anyone could be disappointed.

WOW

[Gradient Keeper]

Yeah, mid Dec-Mar is really the key period for building snow pack. Not that good snowpack can't be built earlier, it's just much more likely to survive into the spring later.

 

DJ droppin-inspired new name?

I'm not quite sure what you mean

[MossMan]

I sobbed uncontrollably while hanging lights in the face of slightly mild sunshine.

Raining up here most of the day!

[Front Ranger]

I'm not quite sure what you mean

 

You've mentioned your flatulence a lot recently...and dolt's new name is "shart".

[Gradient Keeper]

You've mentioned your flatulence a lot recently...and dolt's new name is "shart".

LOL I mentioned it once in a very poor attempt at humor while drawing comparisons to.... well, you know. I could change my username to Rob, or Gradient Keeper. DJ Droppin in my artist/producer name. Maybe I'll come up with something like SnowBallz. I dunno.

 

00z GFS in 2 hours 42 minutes!

[snow_wizard]

Reality check...the winter of 1861-62 didn't have any cold whatsoever until mid December.  Same is true for many great winters.

[Gradient Keeper]

[Model Countdown]
Next up.................
*00z GFS in 2 hours 29 minutes
00z CMC(Canadian) in 3 hours 14 minutes
00z ECMWF in 4 hours 50 minutes

It would be nice to see both an amplified and less progressive pattern on the runs tonight. I'm not overly confident for either. Cautiously optimistic.

 

Think Cold and SNOW!!!! ❄❄☃❄❄

[Front Ranger]

Reality check...the winter of 1861-62 didn't have any cold whatsoever until mid December.  Same is true for many great winters.

 

This winter already blew it early this month.

[MossMan]

This winter already blew it early this month.

Like I say...we can always count on March!

[Jesse]

Ensembles seem to be gradually trending milder.

[Gradient Keeper]

Ensembles seem to be gradually trending milder.

If you mean GEFS? Yeah.

[Deweydog]

Reality check...the winter of 1861-62 didn't have any cold whatsoever until mid December. Same is true for many great winters.

Many of our warm, snowless winters also had no cold, snow through mid December. Hmmmm...

[Timmy Supercell]

Another super torchy day. What a disappointment.

 

Was quite a bit cooler here, 49 for a high compared to 64 on Thanksgiving.

[Guest El nina]

You've mentioned your flatulence a lot recently...and dolt's new name is "shart".

I thought you were talking about dropping a poo.