January 2024 Weather in the PNW (Part II)

[fubario]

1 hour ago, SouthHillFrosty said:

 

got one of them for your OLM homies? gracias.

[the_convergence_zone]

7 minutes ago, Phil said:

There is something to be said for internal consistency in guidance. So rare that I ever say this, but given the relative stability of the GFS/GEFS suite (relative to other guidance) I’d hedge ~65-70% in that direction, with a 30-35% hedge towards other guidance. At least in terms of 500mb pattern.

Vice versa, guidance with the coldest solutions (such as the ICON) have been the most unstable with their solutions at 500mb (for what reason(s), I don’t know).

Though if there’s a mesoscale element to the model differences related to topography/etc, that’s something you all would understand better than me, in which case my opinions above are probably moot. I’m not great with mesoscale dynamics in unfamiliar regions (I’m slowly learning how that works in the PNW but can’t master it without living there).

IMO one of the unique aspects of the PNW is that the giant Pacific Ocean is upstream of us, so these little shortwaves are poorly sampled. It's unclear to me which model(s) are getting hurricane hunter data and where they are sampling, but that could be a big X-factor here. 

I'm inclined to think they will meet in the middle...especially given the number of EPS members that do show a more northerly solution. 

[AlTahoe]

Jesus Christ on a unicycle that fantasy land storm on the Gfs is something else at hour 342. Looks like you model riders will need stock up on supplies if that keeps showing up. lol 

[TT-SEA]

1 minute ago, snow_wizard said:

I thought people were saying the UKMET was warm.  Sure doesn't look like it.

No one said warm... its very suppressed with precip.  

[the_convergence_zone]

6 minutes ago, Front Ranger said:

FWIW, the FV3 hi res shows Portland area getting clobbered pretty good tonight.

 

Also shows a decent Arctic front CZ signature later for Puget Sound.

The HRRR has been hammering Portland as well. 

[MossMan]

Starting to get a bit breezzzzy again 

[LowerGarfield]

24 minutes ago, Frontal Snowsquall said:

Wow, moisture way south. Misses us all.

Except @DRG's cabin just south of Oregon and @MWG in Medford.

[TacomaWx]

9 minutes ago, MR.SNOWMIZER said:

I will bet 50 bux in the end it comes in between Astoria and long beach.

I’m not so sure…I think things might move slightly north at the very most but I’m betting on this mostly being a PDX event and Seattle being on the fringe. 

[snow_wizard]

2 minutes ago, Christensen87 said:

My sister is subbing in Enumclaw and the teachers want my prediction if school will be cancelled Friday due to weather. My first thoughts are of course, no way to tell yet. GFS has snow coming in that day, so it could be a good idea. Don’t think the wind would be an issue yet. What do you guys think? 

Who knows.  I think an inch or so with the Arctic front is a good bet.  Not sure when the snow from the big system will start....assuming it happens.

[Rubus Leucodermis]

The way the ride has been this time, I would not be completely surprised to see the 12Z Euro come up with a more GFS-like solution.

[snow_wizard]

Just now, TacomaWx said:

I’m not so sure…I think things might move slightly north at the very most but I’m betting on this mostly being a PDX event and Seattle being on the fringe. 

I'm betting snow pushes up to Everett at the very least.

[snow_wizard]

1 minute ago, LowerGarfield said:

Except @DRG's cabin just south of Oregon and @MWG in Medford.

Oh....people must have meant it was on the fringe to the south.

[MR.SNOWMIZER]

Haha people are crazy skiing in this, crystal mountain web cams look like a blizzard

[Minion]

6 minutes ago, Christensen87 said:

My sister is subbing in Enumclaw and the teachers want my prediction if school will be cancelled Friday due to weather. My first thoughts are of course, no way to tell yet. GFS has snow coming in that day, so it could be a good idea. Don’t think the wind would be an issue yet. What do you guys think? 

It will be fine 

[MossMan]

1 minute ago, snow_wizard said:

I'm betting snow pushes up to Bellingham at the very least.

Fixed it for you! 

[SnarkyGoblin]

Didn't someone say that the euro follows the gem?  Which was hot garbage for snow lovers in the latest run.

[SnowWillarrive]

Time to pull out Cliff’s favorite. 

[MR.SNOWMIZER]

Just a average 40hr blizzard at the end of the gfs.

[MossMan]

Still open with Chains required…But I’m sure they won’t be open much longer. 

[Weiner Warrior]

1 minute ago, SnowWillarrive said:

Time to pull out Cliff’s favorite. 

This is definitely correct. Wonder if he'll go all in with this

[snow_wizard]

Just to make things more interesting.  The MJO is getting into some good regions for us to be cold. 7 coming up late month.

[MossMan]

2 minutes ago, SnowWillarrive said:

Time to pull out Cliff’s favorite. 

I would be okay with that. 

[Phil]

3 minutes ago, the_convergence_zone said:

IMO one of the unique aspects of the PNW is that the giant Pacific Ocean is upstream of us, so these little shortwaves are poorly sampled. It's unclear to me which model(s) are getting hurricane hunter data and where they are sampling, but that could be a big X-factor here. 

I'm inclined to think they will meet in the middle...especially given the number of EPS members that do show a more northerly solution. 

That’s possible too. Though IIRC the whole “sampling” thing isn’t as true today as it was a decade or two ago. The majority of data ingested into models is satellite data rather than radiosonde data/etc, though of course if there’s a storm or feature of particular importance, it doesn’t hurt to have a more precise read of the atmospheric profiles within said storm or feature.

Still, given I don’t live up there (at least not yet, lol) I usually do give weight to the ideas you all put forth, since your knowledge re: regional climate and mesoscale tendencies (and the model biases that come along with such) is vastly greater than mine.

[SnarkyGoblin]

2 minutes ago, MossMan said:

Still open with Chains required…But I’m sure they won’t be open much longer. 

Bet the Olympics are finally going to look like we're in the middle of winter.

[Brian_in_Leavenworth]

3 minutes ago, SnowWillarrive said:

Time to pull out Cliff’s favorite. 

Cliffs model ran yesterday showed about 9" for Leavenworth.

Just measured.  We had exactly 9".  This model, at least the 1.33K resolution version, is spot on for here time after time.  I have been really impressed with it, so much that I ignore all other forecasts.  Of course it only goes out 72 hours, but any snow maps shouldn't go out any further anyway.

 

[Phil]

1 minute ago, snow_wizard said:

Just to make things more interesting.  The MJO is getting into some good regions for us to be cold. 7 coming up late month.

While I’m wary of using unfiltered RMMs alone to reflect MJO, when they project strongly into phase-7, it increases my confidence that a legitimate SSW will come to fruition.

Some of this amplification is a result of the ongoing minor SSW augmenting the Brewer Dobson Circulation (think of that as a mass overturning circulation in the stratosphere from the equator to the pole), but the MJO position in phase-7 (WPAC) also augments wave driving in a way that is favorable for additional PV disruption.

So even when the current blocking episode wanes, I’m very confident there will be another one in February (likely -NAO centric once again).

[snow_wizard]

This is adequate I suppose.  Even the Fife snow dome is only somewhat effective.

[Rubus Leucodermis]

8 minutes ago, SnowWillarrive said:

Time to pull out Cliff’s favorite. 

4km has higher resolution, and it doesn't show me getting skunked so badly with the arctic front.

 

[SimplySmoothWX]

5 minutes ago, snow_wizard said:

Just to make things more interesting.  The MJO is getting into some good regions for us to be cold. 7 coming up late month.

That coupled with a -PDO (which has its strongest effect here from Jan-March) things could get interesting 

[SnarkyGoblin]

7 minutes ago, Weiner Warrior said:

This is definitely correct. Wonder if he'll go all in with this

It would be a big win for the model if it verified.

[Hawksfan2008]

Rare to see the NBM spit out amounts this high in the sound. 

[Snownerd3000]

2 minutes ago, snow_wizard said:

This is adequate I suppose.

 

[Port Angeles Foothiller]

2 minutes ago, Rubus Leucodermis said:

4km has higher resolution, and it doesn't show me getting skunked so badly with the arctic front.

 

8" for me on the front. Now that is believable. Take notes EURO

[Mid Valley Duck]

The WRF shows about 1.5-2.5" of Ice for the PDX metro area. That would not be good.

[Brian_in_Leavenworth]

Just now, Hawksfan2008 said:

Rare to see the NBM spit out amounts this high in the sound. 

Does the NBM use 10:1 ratios?

[Snownerd3000]

1 minute ago, Hawksfan2008 said:

Rare to see the NBM spit out amounts this high in the sound. 

On my drive into Seattle I was listening to Komo 1000 for traffic update getting into the city as shiz was already bad on 405 south.  Their weather forecast for Thursday into Friday was some light accumulations on grassy surfaces but we'd see freezes over the weekend.  What crack are these mets smoking?

[Rubus Leucodermis]

2 minutes ago, Hawksfan2008 said:

Rare to see the NBM spit out amounts this high in the sound. 

It is heavily influenced by the GFS and its more northerly solution.

[Rubus Leucodermis]

2 minutes ago, Port Angeles Foothiller said:

8" for me on the front. Now that is believable. Take notes EURO

Yes, it shows the usual suspects getting hit by strait effect snow.

[OysterPrintout]

2 minutes ago, Brian_in_Leavenworth said:

Does the NBM use 10:1 ratios?

10:1 bad to good model input ratio yes

[MR.SNOWMIZER]

These Arctic fronts can be really good or terrible, they normally fizzle out once they get down around Seattle.