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Snowy Hibbo

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About Snowy Hibbo

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  1. Hope you are all having a lovely summer Just a quick look at the ENSO SSTs is to look at a rather confusing non-standard setup. +IOD brings warm ocean temps to the Western and Central Indian Ocean. And cooler temps to the Eastern Indian Ocean and Maritime Continent. This looks like a Nino pattern in a vacuum, but then you have got cooling anomalies in the ENSO regions in the Eastern Pacific. And the rest of the Pacific is warmer than normal. What this indicates to me, is that the persistent +AAM atmospheric conditions won’t be shifting too much anytime soon. Another quick thing to note is the cool/warm divide of SSTAs just off the Eastern US Coast, which would be increasing the jet stream there, and making troughing activity in the region more likely. Interesting times as we head slowly into Northern Hemisphere seasonal forecasting season for winter (but not just yet, still the whole of summer to go )
  2. EPS Teleconnection figures from 00z: A continued +AO outlook over the next 15 days. +EPO neutralising to 16th, -EPO to the 21st, neutralising afterwards. A continued +NAO outlook over the next 15 days. Relatively Strong +PNA from the 15th, throughout the rest of EPS outlook, weakening from the 21st. This shows that the Pacific is starting to cooperate in the medium term under the accords of the GSDM, with +GMT and +EAMT in particular occurring over the last few days. But the polar domains of the AO and the NAO (Greenland) are not. We can go on about how the Pacific has been poor, but another factor is that we only really saw a genuine -AO after the SSW for 10-15 days. And that never converted into a proper -NAO. The polar domain has been running against us all season. The SSW happened, but nothing really eventuated. We can't blame the strengthening SPV (in red) above the -NAM/slower zonal winds section of the atmosphere (in blue), from the last days of January, for the lack of a sustained -AO entirely. This is 1. A normal part of the stratospheric process of a SSW, and 2. It is what was actually pushing the -NAM anomalies downwards towards the surface. But however it is plausible to attribute the particular strong nature of the comeback of a strong SPV, to the weakening of the weaker zonal anomalies. But it couldn't have been the only influencer at play. I have circled in orange, a rather extraordinary period of +AO anomaly at the surface for much of February. There could have been downward heat flux from the higher levels of stronger zonal winds. But I can't see the potential for that to be the only cause to that particular anomaly. It's an interesting anomaly that I think would make an interesting topic for a research paper in the near future.
  3. I think the 9-12 March period could work out. There is definitely the spacing in time to make it work, there is certainly the cold to make it work, you really now just need a good surface setup, with adequate precipitation and coastal track. EC and GEM's latest runs have given some relatively good systems for this period. The GFS suite brings large inland rain-bearing lows, but I believe they can push further to the Coast. It has some degree of ensemble support as well. Based on them, the next period for a potential system of some quantity should be around 16-20 March. The reversing MJO signal (weird, but a good sign of things to come) and EPS' suggestion of some +AAM finally pushing through the North Pacific extratropics, makes the later stages of March more hopeful. GEFS also agrees with a D10-D15 speed up of the NP jetstream, but it comes with a +EPO, stretching into a -PNA, so not as good. We want an Aleutian Low playing a role in the mid third of March, to continue the relatively good start to March, in spite of the rest of winter.
  4. GLOBAL WIND OSCILLATION (GWO) These quarterly GWO charts were produced by Klaus Weickmann and Ed Berry from 2008 who devised the GWO phases as well as the GSDM (Global Synoptic Dynamic Model). They then produced some backdated charts from 1957-58. There is not a complete record and most of them cover the winter quarter only. The source for theses charts is on the SCW (South California Weathernotes) which has a vast amount of current and archived data on many of the teleconnections on this link: . The site is no longer fully serviced and some of the current data is no longer auto updating. It is possible that the site will close at any time. So we will prioritise capturing as much useful data as possible, links and charts We wish to ensure that access to the charts will be permanently available to us. The same applies to a number of other sites with current and archived records. 1957-58 1958-59 1963-64 1965-66 1968-69 1969-70 1972-73 1976-77 1977-78 1979-80 1982-83 1983-84 1986-87 1987-88 1991-92 1994-95 1997-98 2000-01 2002-03 2004-05 2005-06 2006-07 2009-10 2011-12 2014-15 2015-16 2018-19 2009 spring/summer 1961-62 1962-63 1964-65 1967-68 1970-71 1971-72 1973-74 1974-75 1975-76 1984-85 1988-89 1995-96 1998-99 1999-2000 2007-08 2008-09 2010-11 2017-18 2016-17 2010 Summer
  5. RELATIVE GLOBAL ATMOSPHERIC ANGULAR MOMENTUM (GLAAM) - ANNUAL CHARTS These annual charts from 1979 to 2014 have been obtained from the archive section on the Nicholas Shiraldi, Albany website which is accessible on this link: It is highly likely that the Albany (Shiraldi) charts will disappear at any time as the site is no longer being updated or serviced. It is possible that the site will close at any time. So we will prioritise capturing as much useful data as possible, links and charts We wish to ensure that access to the charts will be permanently available to us. The same applies to a number of other sites with current and archived records. and the links may stop working. 2014 2013 2012 2011 2010 2009 2008 2007 2006 2005 2004 2003 2002 2001 2000 1999 1998 1997 1996 1995 1994 1993 1992 1991 1990 1989 1988 1987 1986 1985 1984 1983 1982 1981 1980 1979
  6. It's interesting to observe, because that is a +NAMT, that has a descending Alberta High. That is your ideal location for a high in theory. This chart is perfect, except for the big problem with having troughing up the Rockies and down into Mexico, is that is going to speed up the jet, which amps this low behind it, creating a rather warm mess. If there wasn't such troughing in the Rockies and a pushing low behind it, the high would pop right over all of the gradient. And we would have a far more meridional pattern across NA, without it. Instead the Low gets pushed out, and you see a high, reduce any chance of a system after the 5-6 March, for at least 5 days. That is the problem where there isn't really any pressure from the extratropical and polar domains. We want to see a +AAM and westerly momentum, we just don't want to see awkward momentum transports like this, caused by a push back into +AO territory, and possibly the consequences of the fortnight and a bit long WWB in the Pacific finally ending. You want to see solid Teleconnections pressures, not just region specific pressures. Although it creates the opportunity, it also works against us in that it rushes through way too fast. If that High pushes a few degrees further east, and push the Low further east, you would have a far colder system for NYC and surrounding regions. There's plenty of scope for the Synoptics to shift in our favour, but there is plenty of reasons against this too (the season's climatology, and the fact that not a lot of the reasons why this season was so bad have changed now). I hate to be doom and gloom, but this is probably the last good chance at getting snowfall, and it may just be blown, because of the same reasons why they have been so many clippers this season.
  7. The 6th system just moved offshore for this one run, because a more dominant lobe at the 300hPa level, and because of the moisture from the North coming in from a different angle. Westerlies pushed it offshore, and it started far too much offshore as well. It's totally plausible to come again in the next EC run, just if we get a little more Atlanticward activity from the previous low, rather than into Northern Canada. It may very well be weighing the two lows against each other, but there is certainly potential they both come through with some sort of snowfall.
  8. Take the latest GFS run. There is an immense amount of +NAMT, caused by the pushing of the Alaskan ridge down into the Rockies. This is pushing in from the -EPO domain, and downwards, which flicks the jetstream down towards the tropics to connect with the still expected to continue WWB/MJO Phase 8-1, that will via tropical convection add to the precipitation and storm potential for this system. This system would have no upper level GOM links, it is just Pacific moisture with warm Atlantic bombing assistance with a very deep low with very cold temperatures out the back (look at the jetstream heading directly south). This should ensure a large snow bearing system in the 2-6 March period, if these work out as expected.
  9. @Isotherm Just following on your comments in the Eastern US thread in here: It's not overally scientific in terms of gathering data, but in the next little while, there seems to be more purple (negative zonal winds), south of say 30S. These streaks of purple are in identifiable lines in the SHEM, that work in between the rossby waves, the cyclones and anti-cyclones. Then you have the well defined tropical setup with reduced/easterly winds in the IO, and more westerly winds in the Pacific. Then you have the negative zonal wind anomaly in the NP, caused by a number of highs in the region. But by and large the Polar jetstream looks rather strong North of 60N, and also within the Atlantic off the the Eastern US Coast. While there is plenty of things slowing down the pattern in the NHEM, there is not nearly as much there as in the SHEM, and it seems to be more erratic, in "clumps", rather than the stripes in the SHEM. This could be just inter-seasonal forcing. But I think the following pattern might just be what is causing it: Save for the low off Eastern South America (which has a corresponding stronger jetstream), the STR and low gradient is rather flat and remains so. Yet the lows are a bit further out from the poles at the moment, because we are in a -AAO pattern (notice the high right on the South Pole line). This is pushing things out, and has brought snow to the Australian continent in the past week or so. Now the -AAO is set to flip in March, which will move the lows back closer to the South Pole, and make the charts look more like this: The polar lows are back in towards the South Pole, which should create a roaring jetstream, as they look to be making a flat gradient with few deviations with the STRHs. This means we should start to see westerly momentum added in the SHEM in March, which would correspondly show up on the total budgets. - Zac
  10. Yeah, I see that, but I am interested to see that this WWB hasn't affected anything in that world. I think that there is downstream patterns that occur onto the MT > AAM, via FT as the WWB passes Maritime Continent. It's something I will look into. As you said, there is a positive Torque addition in the NHEM sub tropical belt, not so much here in the SHEM, at least looking at FT.
  11. No surprises there.... We are in a major WWB, and it is having a negative effect on the SOI, by pushing a more tropical signal out towards Tahiti. More interestingly, the one thing the WWB is not affecting is the FT It is near it's negative low point, which seems to be contrary to the massive addition of westerly momentum. I don't think it is a coincidence, that the only +FT in the last three months was during the only strong WWB in the Eastern Indian Ocean and Maritime Continent on and around the 25th Dec.
  12. A nice writeup from Tom above The highest AAM anomalies are actually on my side of the equator. And I think we can bring this down to what is happening with the current MJO wave caused strong WWB in the Pacific. Most of the recent WWB-associated activity has been occurring within the Southern Hemisphere. This explains the very negative SOI anomalies in the Pacific (because Darwin and Tahiti are both in the SH). The interesting thing is CFS notes this WWB continuing for a while, a whole month long. This would have continued impacts on extratropical weather down the pipeline. The activity heading out towards the Baja California, also indicates to me, the signs of a strengthening STJ, from the region up to the Eastern CONUS. It has been interesting not to see this activity, stir up major positive frictional torque activity, but perhaps it is the location, rather than the strength that prompts the +FT. I have some thoughts that are best for another time, but hopefully we see some big responses to quash negative AAM anomalies at 40N. The best way to do this starts with a +FT. Interesting times. - Zac
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