SnowGoose69

The NAM was pretty scary though at 84 if you’re in SNE or especially NYC. It’s flat as a pancake but basically on its own at this stage. The NAM almost always has a south bias though beyond 48 with any sort of event that resembles a SWFE. It’s been that way since it’s inception or switch over from the ETA

The NAM at 84 meanwhile has practically no indication this would come north of the PA/MD border

The last 2 weeks and the next 2 weeks are a good example of what if....someone should post an image of what this pattern would have looked like with a positive AO/NAO vs what we currently have. It would be 60-70 every day here

There is a real fine line for sure. Even if the SE ridge pumps enough for the wave to ride along BWI-ACY which is ideal for us the system is still going to undergo dampening which would probably result in a place like Easton seeing way more snow than NYC because you are likely going to lose lift/forcing as this goes more east.

The 2nd or 3rd system is probably the one to watch...the 1st really dampens and strings out on most guidance...it could still change but that is not going to be a huge storm by any means I don't think

Yeah I feel people in DC are getting too happy about this event given there is an SER...this is not 2/6/2010, even if there is blocking in place. Its gonna be next to impossible to see a significant snow event that stays PHL south with the degree of SER we see (and lets face it, its ALWAYS underdone the last few years at this range). I think this could easily be a setup where even this region goes snow to rain

This feels like a 2/8-2/11/94 sort of event...it has potential to be a rare SWFE type setup where the metro is mostly snow or at least all frozen.

I believe shortening wavelength as we progress through Feb would make that link up less likely to occur but I'm not sure on that.

I think some snow may occur the next 10-14 days but the odds of something big are low. If it happens it'll be some type of February 94ish event probably. I don't think in this pattern we are going to get a classic KU or even a big coastal.

I'm beginning to think we need another 82-83/97-98/15-16 Nino to change this

In that setup the block would have to be much further SW. that’s not necessarily an east based -NAO but it’s too east based for the pattern over the US. Also that piece over the northern plains might phase in to an extent. It might work out for New England but not the MA.

I would not be surprised if this is just a repeat of the weeklies from the last 2 winters. They want to keep bringing in the ENSO pattern and it never will happen

Yes and no. Its had trouble resolving the blocking pattern and pattern shift about the same...it does not have ensembles so I could not see those but its Op runs were pretty regularly trying to crank southeast ridging and cutting storms 7-10 days ago and look where we are now. Its still occasionally trying to do it. Its best improvement is it has less of a near term cold bias it seems.

Its probably 2 weeks too fast with it. My hunch is this pattern will go til 2/1-2/5 before there is any chance of a flip

I think it technically nailed 2/8/13 before any other guidance so 2023 might be the next coup

The GFS finally resolved not having the SER now its the only model that next Wed-Fri wants to pull a pre torch ahead of the PV drop...it'll end up wrong on that too

Pretty crazy how both the events at 144 and 210 in N AL and N GA are basically both rain due to lack of cold air

Ensemble wise nothing much has changed. The pac change is still showing but both the EPS and the GEFS are showing signs the AO and NAO could move towards neutral by day 15. Given we are in a La Niña that’s entirely possible as mid January approaches. At the same time though ensembles have been trying to show La Niña type pattern shifts on and off at the end of the long range since late November and have continually failed. Even the weeklies are trying to show it somewhat at week 4. It’s possible the true La Niña change never happens because so far every time it pops on models it never comes

I presented on that storm as a research paper and it was truly a cruel evolution. Almost nobody remembers this but the shortwave or upper disturbance which produced the 12/30 storm was responsible for acting as a kicker to a previous shortwave over the southern US that was supposed to phase on 12-28 or 12-29 with a strong Great Lakes shortwave somewhere in the TN Valley or MA. Instead the 12-30 eventual producing disturbance booted that Gulf one out to sea and the big one didn’t happen. The storm that was initially shown on models 4-5-6 days out for 12-28-29 was a monster that would have hit everyone hard up the coast

Up until recently there were hardly any major events with a positive NAO. Certainly there were some big overrunning type storms or southwest flow events but these borderline KU events with deep coastal lows occurring with positive NAOs is mostly something that’s only occurred in the last decade

Not really. The PAC was really good otherwise, even for the earlier December events which I think two changed to rain at the coast. The pattern out west broke down for a while there in mid to late December.

Even the Para has been trying to crank ridges in the east past day 7 on many of its runs. It hasn’t been as awful as the GFS but it’s still doing it. Just look at the difference in the GFS Op runs today at 12Z compared to the Euro at Day 6-10. One has 534 thicknesses to Atlanta the other has highs of 65 in DC

I think it’s classified on a Niña by some and not others. Same as 96-97 and 89-90 are classified as neutral by some and weak Niña by others. 17-18 is a better example of a La Niña winter with several progressive suppressed deep southern snow events

It is amazing to me how much the GFS Op continues to struggle with this pattern. It just wants to cut and build the southeast ridge on most runs beyond day 7-8. The difference in the 12Z runs today for the Euro and GFS day 8-10 is just astounding and it’s been several consecutive runs more or less with that idea

Yeah it was a good example of terrible pacific good Atlantic with a snow event. I always show that event as an example of what a -NAO does