Typhoon Tip

The majority doesn't appear to have this right, anyway. There is no SSW.... there never was yet. There may be one about Dec 7 or so... but antecedent to the -WPO/ -D(EPO) that was not the case. This is a ridging that is emerging from mid to upper troposphere and the tropopausal heights are elevated around the N arc of the ridge at upper levels; that does have an effect on the morphology of the PV. As I explained the other day, it may be splitting hairs? Either way, a -WPO/-EPO arc can arrive into that scenario however it does, when it gets into that mode, we load ... cold air in the winter. The cold you noted in Canada ( 2-meter temp anomalies... and 850...etc), that is a direct result of the activated loading pattern. This is just -WPO/-EPO, nothing else. Not sure why social media can't help itself but go from 0 to sci fi drama with such little excuse to do so - sometimes I suspect it's society dopamine plague since we've become tech zombies. How's that for sci fi. jesus As far as the colder pattern, this is all greater confidence than people are letting on - a lot of which I suspect is not having patience. Part of the problem of visualizing these changes at long leads ... ( over 15 days in some case...), about 5 days in waiting all the doubts start happening ... People expect to see things now. Meanwhile, models will come in and out of the signal ( operational versions). By the way, here's the 360hr 10 hPa GFS prog... this is a warm intrusion - we'll see if it's real.

Fell for the bait ... after 20 something years of this pastime, too

You're a lost soul to the realm you were meant to roam. Utqiagvik calls to you. The sun just set at that location and won't rise again until January 22nd.

Definitely a colder complexion returned to the guidance overnight. There were some odd solutions there for a couple cycles when considering the principle component/indexes. Likely it was just typical pattern change guidance games all along. We see this going the other way in April where the indexes suggest the season's first big warm up ... but then the GFS wanders off in a spontaneous pita-flop day dream in the other direction. So in this situation .. I'm wondering if we might end up in a split flow type during those first couple of weeks of Dec. There's likely to verify that large scale -WPO/-EPO changing of the guard over the Pacific, but there's been some persistence in the various ensemble clusters to pin the geopotential anomalies along 120 W. Typically that results in flow bifurcation over the Pac NW, with the N resulting stream being a cold loader flow spanning across Canada, while the S branch meanders through the S Rockies... This can be good for overrunning storm types. If the blocking features lose latitude if/where they set up ...that may trigger more +PNA response underneath than we are presently seeing - whole different ball game. But the idea here is a seasonal dump ( we'll see if all this results in more as the times near) of polar-arctic cold at least down to 40 N across the Continent. As far as particularly dailies and what storms form, if/where those do or not... etc etc... too vague for the time being to make much of any play call.

Shhhhh My internal monologue sarcastically said something similar when I saw that run... But it looked less coherent with the EPO aspects... it's like it dropped below the threshold ( probably in error by doing so - ) where it's no longer forcing down stream over the continent by being too weak. That's why it has semblances of the NE Pac mode but dwindles. Goes without saying .. we don't sweat it beyond D7.

That's an ugly Euro run... It's also a fantastic continuity break for a span of time outside of D7 so meh. But it's attempting a -EPO with zero discernible pattern implications for S of 40 N across the continent. that'd be a neat trick.

26 here already

That’s always possible in fast flow but those look spaced reasonably well. It also helps that they’re both flat waves and probably more middling intensity

I don’t understand what the big deal is with the Epstein files anyway… you’re not gonna be seeing the real ones anyway. The only reason why there’s any kind of impetus to release those files finally is because they’re finally done redacting them – obviously

It's more the 29th ... but yeah. It's too low confidence to know about track and amplitude - the latter's probably too strong in this run though. Might be the first multi-region/full synoptic event of the season; don't need it to be heading for the 980s in order to do it. This is open wave NJ model low. They can bomb so we can't through the idea away entirely, but given to the progressive nature ... a middling system fits better.

Fwiw or not ... I'm not a big fan of the MJO unless it's in constructive interference with the WPO mode...or it has a tough time propagating convection out of the marine subcontinent. It has to do that or there's no latent heat flux --> dispersion forcing to the modulate the subtropical coupling to the mid latitudes ..etc. Right now, the RMM shows the wave struggling on the 6 wave number region, probably also because it's negatively interfering with the W. Pac/La Nina. To me that's like a "predictive firewall" ... we'll see what happens if that wave collapse tendency is real. If it is not, then the way may indeed escape the W. Pac gauntlet later in 7 ... The 7 composite is actually a cool anomaly from the NP-GL-NE regions... and then it would be in positive interference in the Americas in 8-1-2. So it's like a yes-no-yin-yang- neg-pos along this wave's progression. I figure the WPO/EPO signal is precedent (there first) ...the MJO arriving late is liable to get damp some. The question is ... does it punch through. I'm aware the RMM has it going nuts in some of the guidance types way out there in late 7. The MJO is not a pattern forcer... it's a pattern modulator. And the latter depends on the whether neg or pos interference. It needs to be positive

But again ... it's may be splitting hairs. If there's -WPO/-EPO through other means, you're ending up in the same consequence.

That's about right.... it takes about 20 days ( three weeks)... I've shown this before but here. This example was 2004. Text book high altitude intrusion event, then nodal mass down welling with 3 or so week lag prior to AO forcing/'blocking' This example actually first became evident over Xmas week prior to Jan 1 ... and the AO crashed by the 20th.

the other clue ... if this pattern change, which we're at t-minus 6 or 7 days from actively reconstructing, was preceded and ultimately coupled to a canonical SSW, the latter would have taken place by the first week of the month. There was nothing...

I don't like the fact that it isn't (first) emergent in the 10 hpa ... This appears to be up-welling from a very strong constructive interference at mid and upper level troposphere between Asia and the N. Pacific. I'm not sure it matters? ha. I mean, whether it's a SSW --> down-welling in the canonical sense and total behavior, or... some sort of fantastic ridge resonance that's bulging the disk from the bottom, the end result may end up with the same consequence... You get blocking and jet distributions S of normal PV latitudes ...and that in this case (sometimes it affects/offloads in Europe/Eurasia preferentially) modeled to favor our side of the hemisphere for a cold mass delivery/jet. It's an interesting question... but if you look at the GFS's 10hpa, no clue there's a warming event. All SSWs in the monitoring history going back to the late 1970s start between 1 and 10hpa, and then down well. This appears to be a "bulging" event. Similar to what Kevin lacks on his anniversary nights...