40/70 Benchmark Posted 3 hours ago Share Posted 3 hours ago 4 minutes ago, mitchnick said: Once the Niño starts to weaken, there should be a return of the sst warmth back west with the trade's influence increasing. Of course, it won't be overnight, which is why a weakening of the Niño sooner than later improves our chances of decent snowfall imho. Absolutely....this is what happens in my composites. The ridges is displaced SE and makes for an awful December, before it lifts northward more into the NAO domain after El Nino peaks and collapses westward. 1 Link to comment Share on other sites More sharing options...
40/70 Benchmark Posted 3 hours ago Share Posted 3 hours ago Here is a section from my polar domain write-up in July. The most glaring commonality between the QBO composite and both the solar and intense El Niño composites is the pronounced ridging stretching from the northeastern CONUS and into central Canada, which obviously is a rather mild signal for the forecast area in the seasonal mean. However, it has been mentioned on numerous occasions that neither of these winter composites are entirely bereft of high latitude blocking or even shorts bursts of severe winter weather. This is evident in the bifurcation of the composite below. This is a signal that is emergent among some seasonal guidance. What is clear is that as El Niño begins to wane and perhaps shift somewhat to the west as the season evolves, the Gulf of Alaska low begins to retrograde, which allows the central Canadian-Northeastern CONUS ridge to lift up into the NAO domain. This mid-to-latter season progression is the crux of the volatility and Modoki-like episode(s) that have been referenced with the respect the overall characterization of the polar domain. The primary risk here for a transition to a significantly colder pattern is that the block is more oriented towards the Eastern portion of the NAO domain, which is especially evident in the more meager El Niño analogs that did not have the very cohesive Gulf of Alaska low that is synonymous with El Niño. The inference is that the development of the more Modoki like intervals during the second half of the season is contingent on the progression of the mid latitudes of the northern Hemisphere growing more redolent of traditional El Niño as boreal winter ensues, which should take place given the forecast for this warm ENSO event to reach an unprecedented magnitude as Mother Nature gives her best shot at the redistribution of that stagnant west Pacific warm pool. A prime example of the failure of this effort is the earlier referenced MC-oriented El Nino event of 2023-2024, which actually maintained a North Pacific ridge more characteristic of cool ENSO, with a split low on either side. This essentially allowed ridging to persist overt the northeastern CONUS as if it were a cool ENSO season. However, it has made clear when discussing the implication of El Niño on the polar domain that the developing uber-El Nino event is unlikely to be as biased towards the MC-end of the spectrum as the 2023-2024 event due to it's extreme intensity, and instead end up more akin to the 2015-2016 event, which had a more subdued MC influence and ultimately did indeed boast a bonafide Gulf of Alaska low. This is consistent with the expectation for the polar domain throughout out the 2026-2027 winter season. Largely void of high latitude blocking throughout the first half of the season before some intervals of a more disturbed polar domain mixed in throughout the second half. This is a theme that is consistent throughout the vast majority of the analogs, which are littered with notoriously wintry periods such as March 1958, February 1983, March 2005 and latter January into February 2016, a stretch which featured the historic east coast blizzard of January 22-24 and the record cold of Valentine's Day. This shift towards fleeting bouts of severe winter weather later in the season is consistent with research concerning the behavior of the higher latitudes during the westerly phase of the QBO, which concluded that the polar vortex is less prone to disruption from Sudden Stratospheric Warmings (SSWs) overall, but grows more susceptible later in the season per what is referred to as the Holton-Tan relationship. This is due to the fact that the default direction of the zonal winds in the polar region is from the west, thus a westerly QBO is consistent with this and is thus less likely to lead to disruption, or a complete reversal of these winds in the case of a technical SSW (Holton, Tan 1980), until later in the season if at all. This is largely because it is theorized that westerly winds in the stratosphere inhibit the development of a stronger Aleutian high, which is more conducive to the development of said SSWs that entail the full reversal of zonal winds that subsequently leads to either a splitting or displacement of the PV. The inference here is that although a positive NAO and stronger than average PV are favored in the DJFM seasonal mean per previously referenced research on years descending from solar max and westerly QBO, the shear magnitude of warmth throughout the entire ENSO basin should disrupt the antecedent MC regime enough to allow for at least some transient intervals of high latitude blocking and potentially severe winter weather later in the season, as El Niño peaks and potentially allows the Gulf of Alaska low to retrograde. Research by Gray et al, 2004 elaborates on this complex relationship between the solar cycle and the QBO phase. 2 Link to comment Share on other sites More sharing options...
Keith Central PA Posted 2 hours ago Share Posted 2 hours ago 9 hours ago, GaWx said: I assume you know that the warmest month of the winter of 1982-3 in the E US, including SE, was Dec by a wide margin. It was a bonafide torch, the only month like that in the SE to NE. The remainder in the SE was pretty close to normal to slightly BN in some areas. December 1982 was very warm but it did snow in NYC in the middle of the month, which goes to show you when it comes to snowfall it's hard to predict.Of course it's hard to snow when the overall month is warm,but it can. it's December 1 1 Link to comment Share on other sites More sharing options...
Keith Central PA Posted 2 hours ago Share Posted 2 hours ago December 12th 1982..then famous snowplow game in New England 1 Link to comment Share on other sites More sharing options...
mitchnick Posted 2 hours ago Share Posted 2 hours ago 8 minutes ago, Keith Central PA said: December 12th 1982..then famous snowplow game in New England I was watching Channel 7 DC 11pm weather segment (though I was living just south of BWI at the time but still watched DC wx forecasts along with Baltimore 's lol) and I noticed that the precip shield had expanded all the way into the WVA panhandle, which was a good 40 miles to my NW. And thought that was strange because the guy had just said the storm was to stay to our south. Then he said "hmmm, that precip is pretty far north for a miss" and I thought Game On Baby!! 1 Link to comment Share on other sites More sharing options...
GaWx Posted 53 minutes ago Share Posted 53 minutes ago 3 hours ago, 40/70 Benchmark said: Yea, it's gone more east-based than I had envisioned, NVM guidance...which was way off. I don't love that, but like I have been saying, I don't think it makes much of a difference when it's this strong. If anything, it probably helps to limit any residual MC influence that would destructively interfere with potemtial big storm windows. So, while that probably puts the nail in the coffin on any hopes of avoiding a pretty mild season, it may paradoxically help in terms of landing that big fish. I may have to shift from a basin-wide to east-based composite, which makes it more likely that the mean ridge ends up se of Hudson Bay. CANSIPS appears to have a significant Modoki bias based on several years of data. I thought it had this bias even before this year. 1 Link to comment Share on other sites More sharing options...
forkyfork Posted 46 minutes ago Share Posted 46 minutes ago so stop looking at it? i don't even look at the gfs Link to comment Share on other sites More sharing options...
forkyfork Posted 39 minutes ago Share Posted 39 minutes ago Link to comment Share on other sites More sharing options...
LakePaste25 Posted 35 minutes ago Share Posted 35 minutes ago 3 minutes ago, forkyfork said: LFG! Been waiting for this to happen. Link to comment Share on other sites More sharing options...
Prismshine Productions Posted 24 minutes ago Share Posted 24 minutes ago I anticipate a very mild first half, with a stout PV, PAC jet and +NAO....a shift should occur during January which will begin as an AK ridge acting as the catalyst for the first real arctic air of the season, and also ultimately act to trigger big NAO blocking in Feb via wave 1 reflection. Essentially us in New England are closing the shades until Winter 27-28Sent from my SM-S176V using Tapatalk 1 Link to comment Share on other sites More sharing options...
LakePaste25 Posted 15 minutes ago Share Posted 15 minutes ago Almost to +3C on CRW. CRW mostly measures surface temps, so at some point I would expect it to mix down which would increase OISST but decrease CRW. 1 Link to comment Share on other sites More sharing options...
George001 Posted 10 minutes ago Share Posted 10 minutes ago 13 minutes ago, Prismshine Productions said: Essentially us in New England are closing the shades until Winter 27-28 Sent from my SM-S176V using Tapatalk A rouge blizzard is certainly possible, but things don’t look good for northern areas. I agree that 27-28 will offer better chances for sustained winter weather. I would much rather roll the dice with a La Niña than a super Nino. Although weak La Niña is preferred, even in some stronger La Niña years my area has gotten hit hard at times. I dont think there has been even one super El Niño year with AN snowfall locally, and all of them are AN to well AN temps. Even the “better” super Nino analogs like 15-16, 82-83 etc were warm with below average snowfall (82-83 was closer to average, but still a bit below and was warm, so still a bad winter by my standards). Link to comment Share on other sites More sharing options...
GaWx Posted 4 minutes ago Share Posted 4 minutes ago 12 minutes ago, LakePaste25 said: Almost to +3C on CRW. CRW mostly measures surface temps, so at some point I would expect it to mix down which would increase OISST but decrease CRW. Here’s the version of CRW anomalies for Nino 3.4 that best takes into account GW in determining anomalies: it’s +2.5C and rising: Link to comment Share on other sites More sharing options...
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