CAPE

The NAO is notoriously unpredictable at long leads. One thing we have to go on is persistence. The NAO has been predominately positive during winter for many years.

Go back and read the previous few pages ITT. This has been discussed at length. Also I am not sure anyone is 'canceling' winter. Well maybe Ji has, but he doesn't count.

It will snow this winter. Projected mean patterns are just that. We normally get a few shots each winter. Last winter was an o-fer for most, and while it could happen again this winter, it probably won't. Nina winters don't often produce above avg snow, and can be super frustrating with the typical NS dominant flow/late developing coastals. I will say this again- the last 2 Ninas produced slightly below median, and slightly above avg snowfall here, respectively. Both produced big snowstorms(one was a blizzard) for the immediate coastal plain, with no blocking. Clearly better outcomes than the so called Nino and warm neutral of the past 2 winters for my yard. And yes, while DC-BWI and west missed both of those Nina events, it wouldn't have taken much for better outcomes in those areas. Ofc this is a imby business, so I don't care.

Significant HL blocking can mitigate a lot of bad elsewhere. Unfortunately we are on a bad run in that dept. I suppose we are due.

Looking at the latest LR global means, some significant changes up top. Lots of blue, and CFS weeklies continue that through November. The -NAO period was possibly just a transitional thing. The CFS run of indicating HL help for the winter months seems to have finally ended. Its h5 depiction for DJF aligns with most other climate/seasonals now. Has a +AO/NAO throughout. The mean EPAC ridge location/orientation could be worse though. Actually has hints of an EPO ridge, esp for late winter. fwiw.

It likes to do this in the LR.

Boilerplate. I guess it's as good as anything else for a general winter outlook.

There are other factors/indices that influence snowfall here in a given winter, as you well know.

Unless it is a legit, sustained west-based block- but that is unlikely to occur unless the AO is also negative. I guess there is some possibility the mean Pac ridge is close enough to the west coast in early winter to pop a +PNA for a time. Some of the climate models have suggested this before the Pac goes to total crap by mid winter. Latest CFS runs have backed off on that idea, and also any semblance of HL help. It is starting to get a clue.

This is true but one thing to consider here is the official method for measuring the AO and NAO phases(surface based), vs the sensible weather impacts we associate with the h5 heights in those domains. They mostly should be aligned, but not always.

The 840 hour GEFS looking good for mid November.

They generally are all depicting a 'typical Nina' look, and we are clearly in a Nina. People get too locked into these monthly means though, as if the h5 pattern will always look like a LR smoothed mean in real time lol. Ultimately, we just cant know, and there will be some chances even if the winter does overall end up a dumpster fire.

The last 2 winters were weak, wimpy undefined Nino/warm neutral, and the sensible weather that resulted could have easily occurred in a Nina. So I guess its debatable, lol.

We pretty sure it wont be a Nino.

I'll go with the black squirrels. I have never seen one imy until this Fall. Now seeing them all over- It has to mean something. Low solar...black squirrels...yeah baby. HL blocking winter incoming.

^This is all good. Expect median, or less, and be content. Much more realistic than thinking you are going to see average or above most winters.

Odds are this winter will be better in the snowfall dept. Would be difficult not to be. It could still be completely awful by most folk's standards though. If your yard received 6" of slop spread over 3-4 events, with 5 total days of snow on the ground, in an overall torchy winter, would that really be more satisfying than last winter?

This doesn't make much sense honestly. Plenty of variability in Nina winters, year to year and month to month.

Having the AO in the negative phase is key for above avg snowfall in DC, and we typically see a -NAO when the AO is negative. It can happen other ways, but it mostly occurs when there is HL blocking.

EL NIÑO/SOUTHERN OSCILLATION (ENSO) DIAGNOSTIC DISCUSSION issued by CLIMATE PREDICTION CENTER/NCEP/NWS and the International Research Institute for Climate and Society 8 October 2020

A legit wintertime -AO/NAO would help our cause immensely. It has been awhile.

Not a flake within 200 miles of the far western highlands for that period on the 12z GFS. Shocked?

None of these seasonal/climate models are very good more than a month out. Even the Euro is pretty bad. That said, as a group they are worth monitoring to get some idea of the big picture pattern. Nice thing about the CFS is it constantly updates, and it has weeklies out to 6 weeks. Makes it more entertaining. It has been on one of its "good look" runs the past few days. What it is currently advertising for winter would be completely acceptable for this area.

True, but it does happen. Remember the NC snowstorm a few years ago while we were smokin' cirrus?

They both "mean something". You have to keep in mind it is a super LR mean- a monthly mean at that. I pay more attention to the height anomalies on these panels, as it is indicative of where the features of interest may set up in general. Outside of a super blocked up pattern though, clearly there will be some shifts in the location and intensity of the + and -height anomalies.