November 2016 Observations and Model Discussion for the Pacific Northwest

[Front Ranger]

That Alaskan troughing is a problem, actually. Need to see more ridge amplification there.

Cold air in interior AK and the Yukon, usually accompanied by troughing, often precedes PNW Arctic outbreaks.

 

Obviously, to lead to an Arctic outbreak, it has to be displaced to a certain extent by ridging.

[Phil]

Cold air in interior AK and the Yukon, usually accompanied by troughing, often precedes PNW Arctic outbreaks.

Sure, but I'm not talking about "cold". I'm referring to the mature cyclonic wave situated there..that's never a good thing and seldom precedes a blast.

 

Would like to see that wave (or technically a pair of waves) situated farther E/SE by a few hundred miles at least.

[bainbridgekid]

Incredible how fast it comes up!

[Gradient Keeper]

6z GFS..... Nice 500mb pattern. Ridge retrogrades. IF we just had amplification we would see multiple cold shots, modified blasts and lots of snow as we see one BC slider system after another. There might be lowland snow on this run as it is, or if not very low snow levels. Real close to being a great run. Painful to see the real potential, but not realized due to the lack of the block amplifying.

 

Onto 12z! begins in 4 hours 23 minutes

[westcoastexpat]

Let's just say Bastardi must be crying in his cheerios right now.

 

As irritating as I find him, I don't see why he'd be crying. The east gets rocked with cold on the GFS. I'd expect him to be gloating, not crying.

 

He hasn't said much about the west, mostly just about how the east is going to be rocked. The east AND west can be rocked at the same time. Dec 2008 was pretty epic out east as well.

[Bodhijr]

Columbia River is due for a good freeze! It's been awhile since we have been able to drive on it!

[FroYoBro]

I hope the weenies understand that nothing shown has been arctic looking on the models yet. Definitely looks like an interesting cool period coming up though. 

[Timmy]

I hope the weenies understand that nothing shown has been arctic looking on the models yet. Definitely looks like an interesting cool period coming up though.

details... the large scale pattern is there or almost there, and while it hasn't advertised a true arctic outbreak here yet, someone is going to get it in the lower 48 and it may be us.

[SilverFallsAndrew]

I hope the weenies understand that nothing shown has been arctic looking on the models yet. Definitely looks like an interesting cool period coming up though. 

 

Thanks for bringing this up I was about to. I think a "warning" shot is very possible though...A lot of good winters had a nice warning shot in the early December timeframe....Like 92-93. 

[Parksvillewx]

Quite windy here last night. Woke me up around 3am. Checked my weather station and highest gust it recorded was around 40mph and it's in a crap spot on my roof to record wind. Gusts sounded much higher.

[Sometimesdylan]

Picked up a half inch of snow overnight here in Tenakee Springs. The thermometer says it is 33, was 35 when I went to bed last night. Think we're getting that whole "wet bulb" effect here right now. Looks like more today. Rain or snow.... what will it be.

 

Just checked thermometer and it dropped to 32... Happy hunting.

[ShawniganLake]

Quite windy here last night. Woke me up around 3am. Checked my weather station and highest gust it recorded was around 40mph and it's in a crap spot on my roof to record wind. Gusts sounded much higher.

Wind warnings for the coastal areas have been issued. Totally calm here.

 

Looks like Mt Washington got a huge dump of snow overnight.

[dairyd]

I use the Bellingham to Williams Lake pressure gradient. A -negative value denotes N-NE flow. I believe typically a gradient of -15 to -18mb produces gusty, strong winds. Anything -20mb+ is when you see high wind warnings. Feel free to correct me anyone if that seems incorrect.

 

http://wxweb.meteostar.com/meteogram/link_pdiff.shtml?choice=KBLI+CYWL

That is very helpful, thanks.  On Saturday, 11/20 we had a 10-15 mph NNE wind with gusts to 20 on about a -5 mb pressure gradient.  It doesn't take a lot to push the air out, particularly if there is a low to the SW, which is why I am suspect of the system this coming weekend with the weak ridge building in the BC interior and the lows hugging the coast pulling the modified arctic air through the canyon and ongoing into the following week with stronger arctic ridges.  It is the classic setup we can get here.  Does everyone believe the cold air is coming down later this week?  Temps seem to move around some on the southern periphery but seem to consistently spill out to western WA next week with parts of EWA in the teens by next week.

[Timmy]

12z out to hour 192, looks like the 00z

[SilverFallsAndrew]

12z GFS looks like a turd sandwich

[BLI snowman]

There's just not a lot of cold air in North America to tap into with this round of potential blocking. Nice enough upper level pattern but it's going to be a struggle to see any deep airmasses with it, as it's looked thus far. 

[ShawniganLake]

GFS is back to having a strong storm crossing Vancouver Island on Friday.  983mb - Big wind potential up here with that, assuming the GFS has a clue. 

[SilverFallsAndrew]

There's just not a lot of cold air in North America to tap into with this round of potential blocking. Nice enough upper level pattern but it's going to be a struggle to see any deep airmasses with it, as it's looked thus far. 

 

Totally agree. 

[Jesse]

PDX would have to average something like 50/43 over the next nine days to avoid a new all-time record warm November.

 

Looking like a tall order at this point.

[SilverFallsAndrew]

I cannot emphasize enough how incredible last nights CFS was for late December and January...

[Front Ranger]

There's just not a lot of cold air in North America to tap into with this round of potential blocking. Nice enough upper level pattern but it's going to be a struggle to see any deep airmasses with it, as it's looked thus far. 

 

The 0z Euro showed plenty of cold air to the north. Just not quite enough amplification. This time of year especially, you need a better upper level pattern to really score.

 

 

[HighlandExperience]

PDX would have to average something like 50/43 over the next nine days to avoid a new all-time record warm November.

 

Looking like a tall order at this point.

Global warming. Hope all the Hillary and Trump supporters are happy about the prospect of no snow again !!

[BLI snowman]

The 0z Euro showed plenty of cold air to the north. Just not quite enough amplification. This time of year especially, you need a better upper level pattern to really score.

 

ps2png-atls14-95e2cf679cd58ee9b4db4dd119a05a8d-8fbU0T.png

 

I think the 00z Euro showcases what I am saying very well. There is a reasonably well placed and well amplified block at 240 hours... and look at where the -10c 850mb temp line is. Hung up north of the border even clear eastward across the continent. You're just not going to see very impressive cold with that, especially to our neck of the woods, in spite of the favorable positioning. There hasn't been much movement of cold air yet across North America. That may very well change shortly thereafter, but for now it seems to be the hang-up.

 

[Jesse]

Global warming. Hope all the Hillary and Trump supporters are happy about the prospect of no snow again !!

 

We're screwed.

[Front Ranger]

I think the 00z Euro showcases what I am saying very well. There is a reasonably well placed and well amplified block at 240 hours... and look at where the -10c 850mb temp line is. Hung up north of the border even clear eastward across the continent. You're just not going to see very impressive cold with that, especially to our neck of the woods, in spite of the favorable positioning. There hasn't been much movement of cold air yet across North America. That may very well change shortly thereafter, but for now it seems to be the hang-up.

 

Well, the EPO has run largely positive this month, and it's usually tough to get cold deep into North America until it goes somewhat negative. There's no doubt the bulk of the cold air this fall has been bottled up on the Asian side due to the -AO, but a true -EPO pattern would definitely lead to cold.

 

You need the right blocking, and while we see things getting closer, it's just not amplified enough to deliver very cold air this time of year. But the 0z Euro clearly showed "cold enough" air to the north. The blocking is decent, but not the type that usually delivers major cold to the PNW in November/early December.

 

528-534 heights over Anchorage is not an Arctic outbreak pattern.

[SilverFallsAndrew]

12z ensembles are decent. Potential for some slightly below average temps to start December...

[HighlandExperience]

We're screwed.

Mountain snow is looking solid in lower elevations at least going into December. Nice change from recent years.

[ShawniganLake]

I cannot emphasize enough how incredible last nights CFS was for late December and January...

CFS monthly has a pretty nice "cold west" look to it. 

[BLI snowman]

Well, the EPO has run largely positive this month, and it's usually tough to get cold deep into North America until it goes somewhat negative. There's no doubt the bulk of the cold air this fall has been bottled up on the Asian side due to the -AO, but a true -EPO pattern would definitely lead to cold.

 

You need the right blocking, and while we see things getting closer, it's just not amplified enough to deliver very cold air this time of year. But the 0z Euro clearly showed "cold enough" air to the north. The blocking is decent, but not the type that usually delivers major cold to the PNW in November/early December.

 

528-534 heights over Anchorage is not an Arctic outbreak pattern.

 

I  would disagree with that, you want to see 850mb temps a little colder than -10c over the Yukon for us to have a prayer of seeing impressive CAA. 

 

I think the first week of December will be a cold air building pattern on this side of the globe. From there, it'll likely take another round of blocking to do the trick for us if we are to see something impressive happen. 

[SilverFallsAndrew]

I  would disagree with that, you want to see 850mb temps a little colder than -10c over the Yukon for us to have a prayer of seeing impressive CAA. 

 

I think the first week of December will be a cold air building pattern on this side of the globe. From there, it'll likely take another round of blocking to do the trick for us if we are to see something impressive happen. 

 

I am thinking our first chance for something legit will be the week after Christmas through the first week of January.

[Front Ranger]

I  would disagree with that, you want to see 850mb temps a little colder than -10c over the Yukon for us to have a prayer of seeing impressive CAA. 

 

I think the first week of December will be a cold air building pattern on this side of the globe. From there, it'll likely take another round of blocking to do the trick for us if we are to see something impressive happen. 

 

That map I posted shows -24C deep into interior AK. Cold air source is not the problem.

 

Again, 528-534 heights over Anchorage rarely produces an Arctic intrusion into the PNW.

[BLI snowman]

That map I posted shows -24C deep into interior AK. Cold air source is not the problem.

 

Again, 528-534 heights over Anchorage rarely produces an Arctic intrusion into the PNW.

 

Deep into Interior AK is not generally a great source for us to see much cold air transported into our region. It really needs to spread eastward (int the Yukon/NW Territories) for us in most cases, and no models currently show much of that through day 10.

[Front Ranger]

Deep into Interior AK is not generally a great source for us to see much cold air transported into our region. It really needs to spread eastward (int the Yukon/NW Territories) for us in most cases, and no models currently show much of that through day 10.

 

Yep, and in order for that to happen you need the right blocking. Which would involve heights higher than 528-534 over Anchorage, 95% of the time.

 

This is not a great blocking pattern that is mysteriously failing to deliver cold enough air because the "source" is too warm. It's just an ok blocking pattern that needs more amplification. Pretty straight forward.

[Deweydog]

560dm or so over Anchorage is typically the magic number.

[BLI snowman]

Yep, and in order for that to happen you need the right blocking. Which would involve heights higher than 528-534 over Anchorage, 95% of the time.

 

That would depend on how cold the air up there was initially, I would think. Given that the entire continent has been perpetually flooded with Pacific air up to this point in the season, it's going to take a rather prolonged or extreme blocking episode to really get the pipeline going for us southern folk. Otherwise the placement of the upper level pattern at the beginning of the month could very well have done the trick for us. 

[Jesse]

Another ridiculously mild day on tap.

[liquidsnow]

It's encouraging to see the Pacific get pretty much shut down at hr 240 on 12z Euro after weeks of mediocre, non-amplified blocking ("flat ridging" as Phil calls it). Also, a SE ridge looks to start developing which could assist in retrograding the ridge to more of a "sweet spot" location, especially considering there aren't any huge areas of low pressure on the backside of the ridge to push it further east or hinder it from pushing back west. Yeah we may not have the coldest air to tap into but at least we are working towards one part of the recipe that we need.

 

Still liking the mid to end of December for a greater chance of lowland snowfall, while the first half works in getting all the pieces we need together.

 

Might be a "turd" to some, but looks semi-promising to me.

 

If it looks like a turd, smells like a turd and sounds like a turd then you can bet it's a stinking turd...

 

You don't want to see that Greenland block develop...or else December could be a snooze and #wintercancel and #whyistherecactusgrowinginmyyard will be trending in the PNW.

 

http://www.tropicaltidbits.com/analysis/models/ecmwf/2016112212/ecmwf_z500aNorm_namer_11.png

[Deweydog]

Another ridiculously mild day on tap.

Midnight highs and/or lows!

[SilverFallsAndrew]

Midnight highs and/or lows!

 

Low 50s is downright cold for this month!

[Abbotsford_wx]

Another ridiculously mild day on tap.

 

Only 43 up here today... surprisingly chilly.

 

Having said that, it's going to be hard to avoid a record warm November. We could squeak into second place behind 1949, but it'll be close.