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Seems improved pattern favoring a SECS pattern is moving up quicker in time, versus late month or a can kick.

Its coming The AO is going negative, atmospheric river for the month of Feb and early March. TPV in Se Canada and the cherry on top - a PV split with immediate impacts per Bamm. https://x.com/bamwxcom/status/1885678378562310475 Buckle up friends. A total SPLIT of the stratospheric #Polarvortex is showing up in all the data. Splits from the top down deliver impacts quick. Winter is coming back with a vengeance late month into March. The troposphere is driving the heat flux into the stratosphere leading to the split so we’d get cold from the initial tropospheric forcing anyway. What then happens with the split is blocking sets up and allows it to linger as seen below with all model NAO/AO.

AO set to go negative by mid Feb.

https://x.com/burgwx/status/1885138563982917803 From Tomer Regardless of whether a sudden stratospheric warming (SSW) event occurs or not, the stubbornly strong stratospheric polar vortex is likely to weaken — both GFS & ECMWF show anomalously strong 100-hPa poleward heat flux: The TPV tends to remain in SE Canada per Bamm https://x.com/bamwxcom/status/1884994744310178230 We have a continued source region of cold air moving into the middle of Feb and beyond. - NAO looks to develop as mentioned, along with a gradual - NAM state.

This is supported by lastest AO forecast. Also, there is a strong heat flux set to take place next week. Expecting to see a - NAM state by mid Feb.

Going to take a while for maritime forcing to become more favorable for the East. Meanwhile, still awaiting for continued signs regarding a drop in the AO. If and when the cold air takes over in the East, it may coincide with a very active weather pattern. Some late Feb and early March analogs are very active precip-wise.

I imagine that configuration helps guide colder air towards our area, and may have a role with the PV being on our side of the NH. I have not heard of any SSW events, but we do not need them the way the Pac has been cooperating.

Not really surprising to see that blocking over the top. If you look at the previous rise in the AO during mid Fall, you will see several cycles down ( each one a little more negative ) which happened over a period of about 6 weeks. The peak - AO occurred about 10 weeks after the mid October + peak AO, however, not sure if we repeat that amount of time this go around. I believe we will see a continuation of the AO gradually trending negative again with the - AO peak sometime in March. This should favor another snowfall threat for the Mid Atlantic.

Sounds like you are aligning your thoughts with HM. You guys are on the same page, makes sense if we keep the cold on our side, then we can score in early March.

Not a great look for the lowlands once again, and still not at climo here despite the frigid airmasses, to a degree wasted potential like usual. Its been a lower Delaware type of winter and a SE US winter so far from a climo point of view, maybe March redeems for areas that have missed the biggest snowfalls. At least the snow has stuck around, which is a huge win for winter weather lovers ! Looking at trends on the distant AO it appears we are getting some signals that the - AO and blocking return later in the winter.

11 degrees here. FYI Blizzard warning in Louisiana. Crazy times.

I thought Bethany was a ride

We really need a f ing MECS . So everyone participates.

Unfortunately another bust in Northern Delaware. Pathetic models. 1/2 inch here.

Wet snow starting with a little sleet. Temp starting to drop.

Yep, MECS, followed by a clipper all while the 540 line remains to our South to the very end of the run.

Thanks for your insights. Quick question, what is causing that area of increased snowfall along and to the East of the upper Easternshore, in areas such as Chestertowm , MD. Newark, De, Wilmington, De and my area here in Middletown, De. It has been a feature that has showed itself on and off for the last few days.

You were corrent about amping up and less SE of I 95. Much higher totals NW. This will turn out to be a nothing burger in Delaware.

I do recall from my childhood , way way back , this type of acrtic front has brought surprises in regards to snowfall being higher then what was forecasted days prior. Will be cool to observe over the next several days. Lastly, not sure about the effect on sensible weather, but the NAO is dropping agian, wonder the implications for Sunday night's event and the later system next week. The NAO HA signal is there between the 22 nd and 24 th.

14 degrees here presently. Noticed they treated the roads with snow showers in the forecast later today.

Mount Holly with only a 30 % probability of snow Sunday evening, that might be updating later today. Snow before the Siberian airmass moves in would be aswesome !

Well, if you look at tracks of low pressure systems over the past say eight years during the winter months, there has been many inland trackers, coastal huggers and our favorite, "the cutter ". Not sure why this is, blocking, Atlantic ocean SSTs, etc. Have not seen many benchmark storms. Maybe others could chime in as to the reason. But yes, the GFS is lost totally. Sad.

Even if so, that might be a temporary feature. Yet to be determined.

Yep, that was my thought as well. Very interesting.

So what is Webb saying here ? Is it that the coldest air never makes it fully to the East and dumps SW like it did in 2021 ? https://x.com/jamesathomas15/status/1879300372474495096 My experience with these brutally cold Arctic air masses that get dumped on/near the Rockies is that they usually sink southward more quickly than models lead you to believe in the medium range, and end up getting dumped a bit further west like the eps/geps has shown for days Pouring this kind of cold air into a mid level trough will entice it to dig more quickly & the +PVa created above the low to mid level cold dome (a stable layer), “drags” the trough base further west.