so_whats_happening

Unfortunately those 10 or so days were not all that fun for here. Eastern NC though I'm sure was just in love with this pattern lol. From the looks of the Nina phase 1 passage is taking place this weekend. Large cold dump with warming through much of the plains showing up. Going forward it does show cold building back up into Canada to be unleashed again at some point maybe the last week or so of February into early March as we move into Phase 2/3?

By using that same logic the law of averages would assume we would have extensive cooler than average year(s) coming up too since we have been an endless year after year warm regime.

Honestly we haven't really needed much influence from the strat this year other than it maintaining at or below average in strength most of the season. i'd rather have the 500mb take the lead but it would have been nice to lock it in with an actual split. I will not be looking forward to a below average March and April if one were to occur this late in the season.

https://www.geo.fu-berlin.de/en/met/ag/strat/produkte/winterdiagnostics/

Vortex stretching is the term but Im still not seeing a split take hold even with the Euro to 240. It took roughly 30 days to translate to the surface in 2018 (split occurred around the first few days of February) leading to the snowfall events around presidents day and into March. Much different outlook this go around.

All this to say I do want to go out with a bang for the season but my hopes are slowly fading like the winter season.

Unfortunately it still looks as though things will be intact through Strato to Tropo. There has been residual high latitude blocking on the Pacific side of the arctic a lot this season which has allowed us to remain relatively cold through many of the months. If we can hold that pattern into the second half of February as things relax yet again I would not be surprised at a similar progression as we saw in January for February. The SPV just does not get demolished like we typically want to see. Well again we saw something similar to this last year around this time. From about the 3rd week of February to mid March there really was not a whole lot that took place. I want to say there was a quick snowfall that snuck in but this was the overall pattern at 500mb after the event took place. The graphs below show a funky wave 2 tried to set up but ultimately ended up being a wave 1 event and tiny lobe was over Greenland for a bit. Similar things don't always produce the same event but I wouldn't expect much out of this if we go down that path. That is actually fairly typical in split events (if the split event were to occur) the larger more intact lobe goes to Eurasia while a piece splits off to our side. It is the lack of a true split that leads to almost being another wave 1 displacement event again fairly similar to last year at this time. This was what the Euro and GFS had leading up to the event. I wish I had saved the later portion but I guess I deleted stuff.

This is rather disappointing and honestly can't say I'm surprised. Something like this happened very similar last year around this time with the pinching off of a little lobe of SPV in the Eastern US/ SE Canada. It was around mid to late February when this started to take hold.

DCA _ NYC _ BOS _ ORD _ ATL _ IAH _ DEN _ PHX _ SEA -2.2 -2.3 -2.5 -1 -0.4 0.9 2.1 2.4 1.6

We are officially in a WQBO descending phase so we should be right near that transition come next winter so may be a little interesting to start off. Not sure about the transition to full on Nino but plenty of time to discuss.

Fair point it really has been awhile for that type of pattern. There is a large amount of cold air this year which I have been told ad infinitum that this will not be a thing going forward. The longevity is something else this year.

Yea seems like a coast to coast type of pattern. Which is not terrible for this time of year makes me happy to see a potential moist pattern finally trying to set up regardless of snow or rain.

It does tend to translate to the surface quicker this time of year. As for what Stormchaserchuck has said it needs to be a large event that takes place to really nail that possibility in. I have this feeling we may fall short of an actual split but overall I don't think it impedes our overall pattern progression. The split would just help lock in the pattern longer but at this rate im fine with it not locking in. If we somehow get this system over the weekend I don't know where we will put the snow as it has taken a huge effort to clear what we just had and area wide saw 8-12" of snow/sleet (we saw about 10")

If you click on the link I provided it is important to note there are not a lot of examples to determine either ENSO neutral or Nina of a solid phase 1 passage in February and the resulting effects. Nino is not there at all which is a bit strange. If you look at the Nina depiction it is a big cold press into the east based of the 500mb pattern with a follow of warming into the plains which would alleviate much of the east at some point. Do I think it will happen, well I honestly would not be surprised if we relax the cold pattern a bit but im not expecting torch like behavior. To me it seems the results are more of a mixed bag and could easily be explained by other more prevalent signals such as PDO/ PNA/WPO/ NAO etc. If we do indeed get this SPV split all bets are off into either direction of where we go but one would assume we tend to re enforce the pattern we currently would have leading into the split.

Surface reflection of the Nina is starting to dwindle a bit more quickly so I would assume the idea is the influence as we get into February will be more muted in time. I would like to see just how much of the waters with depth east of Japan have been chewed up this year still have and will probably continue to have the -PDO tongue for quite some time. https://psl.noaa.gov/map/clim/sst.anom.anim.week.html