CAPE

BWI: 10.7 DCA: 7.9 IAD: 9.5 RIC: 4.5 SBY: 4.2

Mount Holly has had heavy rain wording in the forecast for here since yesterday. I'm thrilled.

35 when I went to bed. 46 now. Looks like rain by late morning.

The November edition of the CanSIPS is out. Pretty meh overall, but not as bad as last month. Typical boilerplate Nina look with little to no help in the AO/NAO domain. December and March have the "better" h5 looks. Positive temp anomalies throughout.

Been tracking this for awhile on the extended GEFS and EPS weeklies for mid to late Nov. Good to see it showing up on recent op and ens runs now that they are in range. The look on the12z run today would probably suppress the storm track so far south we would miss all the cold rain.

In theory, without considering other factors, it would be "better". We really want the forcing to be a bit further west/further east though.

Not much group think here. Might lean towards weenie think lol, but overall I think we have a pretty nice exchange of information and independent/objective contributions wrt possible outcomes for the upcoming winter. I read the CWG article that included your general thoughts, so please expand on those itt.

Yeah we had a 'snow drought' until the cold powder event at the end of the month ( a fav of mine) but it was hardly a torch lol.

The only concern in my mind is if the SPV remains strong and begins to couple with the troposphere and eventually we end up with sustained lower heights down toward the surface. If that sort of thing happens in the Fall it can become a fixture for winter.

Fwiw, GEFS/extended GEFS still depicting increasing h5 heights up top in about 2 weeks.

Damn, the opinions of BAMWx got some people shook.

I'll go with DT's ideas for the upcoming winter.

That oddity in the regular cycle in 2016-17 really stands out. Makes one wonder if that sort of thing will become more prevalent. I suppose it could have simply been related to the strong Nino during that period, or maybe a sign of things to come.

That tends to be the case with the "legit" blocking winters. Doesn't mean we can't get some HL help though. SPV is not likely going to be disturbed in the near term based on current forecasts. WAFz looks minimal over the next 10 days. Unless the SPV becomes becomes a persistent, giant blue ball of death over the coming weeks and couples to the troposphere, there is still the possibility of HL + h5 heights developing towards the end of November as the long range GEFS and EPS are suggesting. Time will tell, as always.

There is a generally accepted connection between the easterly(negative) phase of the QBO and disruption/weakening of the SPV, but any direct correlation between QBO phase and HL blocking episodes seems a bit more nebulous. It may be that winters with sustained blocking are more associated with easterly QBO due to increased likelihood of a weaker SPV, and this leads to development of a sustained -AO. By the same token, if the SPV remains more intact, but not an absolute beast (say in a somewhat weak westerly QBO), with no coupling to the troposphere/towards the surface, periodic HL blocking episodes may still occur.

I would take it because its pretty rare, and getting cold and and snow when the days are the shortest is cool.

I'm good with QBO 101. But thanks.

The transfer of heat from the equatorial regions to the high latitudes is necessary to build anomalous heights there/warm the upper atmosphere and potentially weaken/disrupt the SPV, so it makes sense there is a connection between the MJO and the AO. The QBO also has an impact as a modulator, and even though it is currently positive, it is only weakly so at this point. I don't know enough about the intricacies of the processes involved and the tendencies (eg location and magnitude of tropical forcing, ENSO state, QBO phase, etc). Above my pay grade. It's interesting, so keep us updated with the techno geek discussions on SW potential.

Continuing to monitor trends in the LR guidance for HL +height anomalies, because it may be the only thing that can save us, along with some semblance of a decent Pacific for a time. Below is the extended GEFS for a month out- towards the end of November, and below that is the Euro(weekies) for approximately the same time period off of the free site. Crappy graphics but I think you can see the look is very similar, and would be an acceptable one heading towards Dec.

Not unrealistic in a Nina.

Yeah I am just looking for hints as we head towards December. There are some thoughts that the first part of winter may favor higher h5 heights up top, while the PAC hasn't gone full puke mode yet. CFS doesn't have a particularly favorable AO/NAO, but hints at a ridge over/north of AK for Dec and Jan.

The GEFS extended range continues to advertise some improvement in the high latitudes for mid to late November. We shall see how this works out, but if there is to be some semblance of a -AO/NAO as we head into December, we should continue to see indications on guidance over the next few weeks.

Yeah it was EPO/WPO driven. The AO/NAO was predominantly positive to neutral at times.

It did seem so easy. It was like the inverse of what we typically see. Temps would start off marginal than get colder as the snow fell. (-AO/NAO) The exception was the late Jan cold powder moderate event with temps in the mid teens. I loved that one, as it ended the "snow drought" and we could see the potential in the LR for what was to come in Feb. That was one winter where "we"(relatively speaking) actually worked. lol.