December 2020 Weather Observations for the PNW

[Christensen87]

Massive windstorm again showing up on the 18z a week from today for western WA, followed by some snow with another low coming further south into OR. 

[Gradient Keeper]

4 minutes ago, AbbyJr said:

Click the Twitter link and you can read through the whole thread.

That was some seriously impressive detailed analysis he did. January 2004 was one of 3 main analogs he was using based on an Aleutian low, SSW, -ENSO. I would gladly be just fine with a January 2004 repeat.

[AlTahoe]

1 minute ago, Christensen87 said:

Massive windstorm again showing up on the 18z a week from today.

Yeah that is starting to get concerning. If a low of that strength comes onshore in Washington lake Tahoe will get winds in the 80-110mph range down in town. I would rather not have that happen. 

[TheNewCulverJosh]

This was the end of the 220 PM Portland AFD.

 

Finally something to keep an eye on...while most model guidance
does not show it at this point, the overall weather pattern
appears at least somewhat conducive for a larger scale windstorm
to affect at least a portion of the waters off the Pacific
Northwest Coast towards the middle of next week. -BPhillips/Neuman

[TheNewCulverJosh]

Druncle was nothing to stumble in an alley about.

[SouthHillFrosty]

Everybody scores with this model run for wind

[SilverFallsAndrew]

16 minutes ago, DJ Droppin said:

That was some seriously impressive detailed analysis he did. January 2004 was one of 3 main analogs he was using based on an Aleutian low, SSW, -ENSO. I would gladly be just fine with a January 2004 repeat.

When was the SSW in January 2004? Because unless it was in December it would not have had much to do with the pattern we ultimately experienced. 

[Deweydog]

Gonna be a tough pattern for models to latch onto any one solution.  Lots of energy just kind of roiling about within the broad trough.  Jet support is kind of sporadic.  

[Cloud]

6 minutes ago, SouthHillFrosty said:

Everybody scores with this model run for wind

60+mph gusts for Seattle? That's very concerning. 

[Front Ranger]

16 minutes ago, AbbyJr said:

Click the Twitter link and you can read through the whole thread.

Here we go. Of course, given timing it's hard to attribute the late Dec 2003/early Jan 2004 events in the PNW to the January 2004 SSW. But Jan 1960 did have an Arctic event and Feb 2006 had a very brief one.

Assuming the 2020 SSW occurs in January (and we aren't too strict on ENSO), then there are only 3 years with Aleutian Low/Urals High in December that were non-El Niño (many were Niño). They are 1959-60, 2003-04 and 2005-06. 

[SouthHillFrosty]

Looks like Tacoma could see sustained gusts of 48mph+  for over 12 hours on Jan 5th @TacomaWaWx

[Kolk1604]

26 minutes ago, DJ Droppin said:

That was some seriously impressive detailed analysis he did. January 2004 was one of 3 main analogs he was using based on an Aleutian low, SSW, -ENSO. I would gladly be just fine with a January 2004 repeat.

A couple of weeks of snow ending with a serious overrunning event and freezing rain. My winter vacation was extended for 3 days. I'm down. 

Of course, winter was over after that. I think everyday was in the 50s until spring. 

 

[Deweydog]

11 minutes ago, SilverFallsAndrew said:

When was the SSW in January 2004? Because unless it was in December it would not have had much to do with the pattern we ultimately experienced. 

It happened just after the Arctic pattern, so not relevant to that particular event.  Probably maybe aided the close call late in the month.

Ironically, the event in January 2003 was much stronger.

[SilverFallsAndrew]

3 minutes ago, Front Ranger said:

Here we go. Of course, given timing it's hard to attribute the late Dec 2003/early Jan 2004 events in the PNW to the January 2004 SSW. But Jan 1960 did have an Arctic event and Feb 2006 had a very brief one.

Assuming the 2020 SSW occurs in January (and we aren't too strict on ENSO), then there are only 3 years with Aleutian Low/Urals High in December that were non-El Niño (many were Niño). They are 1959-60, 2003-04 and 2005-06. 

I would be good with a January-March 1960 redux. 2004 had essentially nothing in most of the PNW after the early January event. 2006 had the brief sharp arctic intrusion in late February and some snow showers in March that produced some spotty accumulations in NW Oregon. 

[Timmy Supercell]

1 minute ago, Kolk1604 said:

A couple of weeks of snow ending with a serious overrunning event and freezing rain. My winter vacation was extended for 3 days. I'm down. 

Of course, winter was over after that. I think everyday was in the 50s until spring. 

 

It was a full week off for the Beaverton School District. That storm hit right when kids got off winter break.

Same thing happened Dec 2008, it all started a week before break, and that was an extended week off.

[SouthHillFrosty]

[SilverFallsAndrew]

The upcoming week is going to produce a ton of mountain snow. 

[SouthHillFrosty]

WOW

[SilverFallsAndrew]

The pattern coming up is not looking incredibly wet in the lowlands (Though the EURO is a lot wetter than the GFS), but it is looking pretty wet for orographically favored areas, which is going to be great for the snow pack. 

[SilverFallsAndrew]

The GFS seems to be trending towards just keeping the storm parade going through the long range. Honestly it would beat west coast ridging. 

[Omegaraptor]

PDX at 39. Nailbiter!

Sub-40 looks just about guaranteed at HIO. They are stuck at 37.

[TigerWoodsLibido]

Willamette Valley Special?

[Chewbacca Defense]

41 minutes ago, TheNewCulverJosh said:

This was the end of the 220 PM Portland AFD.

 

Finally something to keep an eye on...while most model guidance
does not show it at this point, the overall weather pattern
appears at least somewhat conducive for a larger scale windstorm
to affect at least a portion of the waters off the Pacific
Northwest Coast towards the middle of next week. -BPhillips/Neuman

Kinda crazy for them to give it any kind of mention this far out, that in and of itself is noteworthy of the potential.

[TT-SEA]

1 minute ago, Chewbacca Defense said:

Kinda crazy for them to give it any kind of mention this far out, that in and of itself is noteworthy of the potential.

The overall pattern for the next week is pretty locked in and it will be a pattern that is ripe for windstorms and its worth mentioning.  

[TheNewCulverJosh]

3 minutes ago, Chewbacca Defense said:

Kinda crazy for them to give it any kind of mention this far out, that in and of itself is noteworthy of the potential.

Lots of cold and not so cold near each other.  Where is that dividing line going to end up next week?  I would say it stops in Seattle with most Portlanders luck :).

[Kolk1604]

28 minutes ago, SouthHillFrosty said:

WOW

Game.Set.Match

Please verify lol

[TheNewCulverJosh]

2 minutes ago, Kolk1604 said:

Game.Set.Match

Please verify lol

Not much of an inland push on the winds though.  Looks like more of a coastal storm.

[Phil]

42 minutes ago, Deweydog said:

It happened just after the Arctic pattern, so not relevant to that particular event.  Probably maybe aided the close call late in the month.

Ironically, the event in January 2003 was much stronger.

FWIW, the initial stages of the 2003/04 SSW began in late December. PV was already taking body blows during the 2nd week of December, with 10mb u-winds roughly half their climatological speed by the winter solstice.

[Kolk1604]

4 minutes ago, TheNewCulverJosh said:

Not much of an inland push on the winds though.  Looks like more of a coastal storm.

Lame. It looks good though. Plenty of time to change.

[Blizzard777]

48 minutes ago, Cloud said:

60+mph gusts for Seattle? That's very concerning. 

Not a fan of anything in that range.  Putting in a request to notch it down just a bit 

 

39/31 so far today

[Phil]

33 minutes ago, SilverFallsAndrew said:

The GFS seems to be trending towards just keeping the storm parade going through the long range. Honestly it would beat west coast ridging. 

Should see a substantial retraction of the jet starting mid-month.

[TheNewCulverJosh]

2 minutes ago, Jginmartini said:

Not a fan of anything in that range.  Putting in a request to notch it down just a bit 

 

39/31 so far today

Looks like a run of the mill, coastal/NW interior windstorm.  Don't see 60 even making it inland anywhere.

[Deweydog]

3 minutes ago, Phil said:

Should see a substantial retraction of the jet starting mid-month.

Add a week and you’re golden.

[Blizzard777]

2 minutes ago, TheNewCulverJosh said:

Looks like a run of the mill, coastal/NW interior windstorm.  Don't see 60 even making it inland anywhere.

We shall see how it plays out ! 

[TheNewCulverJosh]

Working on another sub-28 high...day.  27.7/15.3 today after 26.7/21.5 yesterday.  Not bad for a little inversion.

[Front Ranger]

The jet will almost certainly retract at some point next month.

[Phil]

3 minutes ago, Front Ranger said:

The jet will almost certainly retract at some point next month.

Yeah it kind of goes without saying. Once +EAMT ceases to be source for AAM, flow across the NPAC could get real wavy real fast, given the circumstances.

[SilverFallsAndrew]

PDX has achieved 40. Knew they would find some way to pull it off. Calendar year 2020 will go down with 0 sub-40 highs.

An almost wintry 38/24 today at SLE. 

Still better than even odds SLE has already seen their coldest max of the winter with the 33 on Christmas Eve. 

[Gradient Keeper]

3 minutes ago, Phil said:

Yeah it kind of goes without saying. Once +EAMT ceases to be source for AAM, flow across the NPAC could get real wavy real fast, given the circumstances.

EAMT East Asia or Eurasian Mountain Torque? or no?

[Phil]

Global SSTA anomaly is finally coming down to Earth. Only ~ 0.1C above 1981-2010 climatology now.