CAPE

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.

This is probably the sort of look we have to "hope" for. Latest CFS h5 mean for December. Maybe if the PDO goes positive it can aid in sustaining an early winter PNA-ish ridge for a while before the pattern retros and turns to complete suckage. Just a bit of help up top here too. Fwiw, CFS looks decent for Jan as well. All the usual disclaimers apply.

I took a peek at the monthly h5 means posted in the NE thread. December isn't that bad, with a west based -NAO, and the Pac ridge s/w of the Aleutians' has not yet become an absolute monster. Most likely the NAO would just keep us from torching, but if that PAC ridge is not yet a fixture and/or is positioned a bit further NE, ya never know. Verbatim that would probably produce for central and northern NE.

The CFS yo-yo is back to advertising a general h5 pattern for winter that could certainly tease, and likely never deliver.

I am down for this. Need to get acclimated to the new normal. Resistance is futile.

Just saw this thread on the character of the Nina from HM.

I am gonna beat Mersky to the punch, and give you a weenie here. Make that multiple weenies.

How is this relevant? Give me some hard numbers, not anecdotal crap. And not some puny data set, either.

October is not a winter month. Wrong thread.

You might as well stop monitoring this. It is clear where it is heading as we move into winter. There is nothing particularly good that can result from this, esp in a Nina.

That is simply a function of a smoothed mean. The primary takeaway on that panel is the location of the average positive and negative h5 height anomalies for the month. You cant just ignore the colors and focus on the height lines. The +(-)heights generally correlate with the temp anomalies at the surface. I wont bother posting that panel- you can imagine what that looks like lol. Clearly these models are not very good at this range, so hopefully that area of +heights in the PAC ends up parking further NE, shifting the phase of the longwave pattern some. That would suppress the SER and give us a better chance for cold air delivery here.

That is a pretty terrible look for a LR h5 height anomaly mean. But sure, its a smoothed mean, so there would obviously be some perturbations in the overall pattern. Big picture is crap though. The CFS, CanSIPS. JMA, etc, might all have the wrong idea at this juncture, but it fits recent winters, and is characteristic of Ninas in general. It really is all about the placement/strength/orientation of the Pacific ridge. If we luck into a legit HL block, even if the EPAC ridge parks in an unfavorable location as currently advertised, the impact could be mitigated somewhat.

That' is typical. It will eventually hone in on the most likely solution though. It has pretty much been the only climate model pushing a half decent Pacific and favorable HL look.

CFS seems to be off the crack and now looks pretty much identical to the CanSIPS for early winter now.

Its not decadal. Unless you mean we see a -NAO an average of once a decade lol. That's probably about right over recent decades. There may be some cyclical nature to it, but with a longer period. The NAO has been predominantly positive since the early 1980s. The 40-50 year period preceding that, there were more negative phase years than positive. IIRC, the frequency of ++NAO years has increased since the early 1990s. Somewhere in this thread I posted a long term time series of the NAO phase (or maybe it was the AO) for the winter months. I cant find it atm. There is a significant correlation between the AO and NAO though. A legit -NAO (not transient bootleg crap) typically occurs when the AO is negative.

We should be beyond the point of having to use disclaimers on this stuff,, but the climate models are what they are, and ofc we are looking at projected mean patterns. No, we should not expect wall to wall winter(probably ever), but otoh, there will likely be a few weeks within climo winter with some cold and chances for winter weather, even in an overall crappy pattern.

The October (full edition) of the CanSIPS is now out. Looking at the monthly h5 height anomalies, it is pretty much a dumpster fire for DJF. The EPAC ridge is a one eyed pig throughout, but gets worse for Jan and esp Feb. Eastern ridge, and no help up top. Temp anomalies for DJF-