MN Transplant Posted September 19, 2012 Share Posted September 19, 2012 In case anyone wants to calc. the avg. snowfall for weak Ninos that have followed Ninas (I don't have the data): DCA -PDO DJF: 1911-2, 1951-2, 1963-4, 1968-9 21.8, 10.2, 33.6, 9.1 +PDO DJF: 1904-5, 1939-40, 1976-7 41.0, 25.3, 11.1 BWI -PDO DJF: 1911-2, 1951-2, 1963-4, 1968-9 22.4, 14.1, 51.8, 18.6 +PDO DJF: 1904-5, 1939-40, 1976-7 40.7, 23.4, 11.1 Hmmm. Link to comment Share on other sites More sharing options...
brad1551 Posted September 19, 2012 Share Posted September 19, 2012 Wes, I hear you on not being convinced but weak-nino's are better then Neutral for the most part. El Nino's have a better moisture supply!! I will know more the later part of October or early November before I make any type of forecast. Always a road bump and changes in patterns to make a soild forecast yet. Preliminary's are one thing and a overall forecast is another. Even are Arctic sea ice being so low could play against us possibly. Time will only tell and thanks again Wes!!!! Link to comment Share on other sites More sharing options...
easternsnowman Posted September 19, 2012 Share Posted September 19, 2012 If you notice BWI does a little better than DCA in a weak nino especially with a -PDO which we'll probably have. Link to comment Share on other sites More sharing options...
usedtobe Posted September 19, 2012 Share Posted September 19, 2012 In case anyone wants to calc. the avg. snowfall for weak Ninos that have followed Ninas (I don't have the data): -PDO DJF: 1911-2, 1951-2, 1963-4, 1968-9 +PDO DJF: 1904-5, 1939-40, 1976-7 Larry, I'm not sure we have enough cases to have such a break down mean much statistically. Link to comment Share on other sites More sharing options...
GaWx Posted September 19, 2012 Share Posted September 19, 2012 DCA -PDO DJF: 1911-2, 1951-2, 1963-4, 1968-9 21.8, 10.2, 33.6, 9.1 +PDO DJF: 1904-5, 1939-40, 1976-7 41.0, 25.3, 11.1 BWI -PDO DJF: 1911-2, 1951-2, 1963-4, 1968-9 22.4, 14.1, 51.8, 18.6 +PDO DJF: 1904-5, 1939-40, 1976-7 40.7, 23.4, 11.1 Hmmm. So, regarding weak Ninos that follow Ninas, avg. for all/-PDO only/+PDO only: 1) DCA 22"/19"/26" vs. ~17" longterm avg. all winters. Median of the 7 is 21.8" vs. ~12" longterm median all winters. 2) BWI: 26"/27"/25" vs. ~21" longterm avg. all winters. Median of the 7 is 22.4" vs. ~16" longterm median all winters So, looks good overall vs. avg. and median of all winters, but with the typical large variance one would expect with snowfall. Due to this variance (snowfall is so hit and miss) and there not being a large sample size, statistical crediblity isn't high, especially for the breakdowns for -PDO vs. +PDO snowfall. (For temp.'s I think credibility is decent as it makes met. sense for +PDO's to be colder than -PDO's and temp.'s aren't nearly as hit and miss as snowfall.) However, I do think these stats help somewhat in giving at least a hint of what might occur and at least suggest less than the average chance for a horrible season. For DCA, there really isn't anything far below the median. The three that are slightly below are 1951-2 (warmest by far of all 7 winters), 1968-9, and 1976-7. For BWI, only one of the seven is significantly below the median (1976-7), two are near it, and four are well above it. Link to comment Share on other sites More sharing options...
GaWx Posted September 19, 2012 Share Posted September 19, 2012 Larry, I'm not sure we have enough cases to have such a break down mean much statistically. With snowfall being so hit and miss (large variance), the stat. credibility isn't high, especially for the -PDO vs. +PDO snowfall breakouts. I do think temp. breakout has more credibilty since it makes met. sense that +PDO's would be colder. Even though the focus of posters is on snowfall outlooks, the high level of variance for snowfall often keeps me from trying to predict it. That's one reason I often focus only on temp.'s. Regardless, looking at these seven analogs together certainly beats looking at any one individual analog from a stat. credibility standpoint. Also, since DCA and BWI are not that far north, it makes met. sense that weak Nino's being sig. colder than normal on avg. produce a bit more than the normal/median snow on average at those locations. Let's face it: snowfall is incredibly difficult to predict, especially for locations not that far north. So, I figure that looking at these seven analogs is about as good as anything as far as trying to get at least some feel for the range of likely possibilities for the upcoming winter. In this case, it would appear to be somewhat more in favor of good snow than against it (vs. longterm averages/medians) for weak Ninos that follow Ninas fwiw. Link to comment Share on other sites More sharing options...
eurojosh Posted September 19, 2012 Share Posted September 19, 2012 GAWX - thanks, I found that a very clear post. As a non-scientist, I hope this question isn't too dumb: It seems like there's always a lot of debate about which factors are most important to winter forecasts for our area - pdo, nao, ao, nino, someone even argued for siberian snowcover earlier. Why isn't it possible to look at the top 10 or 15 variables, see the correlations, and then make a prioritized list of which variable is statistically most correlated with, say, temps or snowfall for purposes of long range planning? Thanks. If this is a dumb question, please don't feel free to pile on me... Link to comment Share on other sites More sharing options...
Quixotic1 Posted September 20, 2012 Share Posted September 20, 2012 GAWX - thanks, I found that a very clear post. As a non-scientist, I hope this question isn't too dumb: It seems like there's always a lot of debate about which factors are most important to winter forecasts for our area - pdo, nao, ao, nino, someone even argued for siberian snowcover earlier. Why isn't it possible to look at the top 10 or 15 variables, see the correlations, and then make a prioritized list of which variable is statistically most correlated with, say, temps or snowfall for purposes of long range planning? Thanks. If this is a dumb question, please don't feel free to pile on me... There are a few reasons but the biggest one would be lack of data points. Link to comment Share on other sites More sharing options...
WEATHER53 Posted September 20, 2012 Share Posted September 20, 2012 I agree that high latitude blocking would be helpful. That is the case with about any ENSO phase. However, keep in mind that weak Ninos overall (longterm) have been the coldest ENSO phase on average for much of the E US (colder than mod to strong Ninos, neutral, and Ninas on avg.), especially those following La Ninas. So, if we can get the blocking, look out below! Those that also have good blocking (-NAO/-AO) have been especially cold. Granted, without an accompanying halfway decent -NAO, the chances for a cold winter are admittedly low. That's not to say that a weak Nino winter following a Nina can't be quite cold (1904-5). It also helps to have a +PDO averaged out over DJF as 1904-5 had. Admittedly, with the PDO so negative recently, the odds are against it becoming + in time for the winter. However, I do wonder if a persistent +PNA can provide enough feedback to raise the PDO a good bit. It will be interesting to see whether or not the current +PNA pattern will do just that between now and 10/1. This is what I posted elsewhere a few days back about weak Ninos following Ninas broken out by PDO: **I'm not addressing snowfall in this post. For snow, I'll leave it up to you to see what you got during these years if you're interested as I don't have this readily available.** The good news for cold chances is that we're almost definitely going to have a weak Nino peak this fall /winter and we already know it followed a Nina. Now, if I want the best shot at a very cold winter for the E US during a weak Nino that follows a Nina, I'd certainly hope for a +PDO for DJF (along with a -AO/-NAO, of course) as these charts illustrate well: +PDO weak Nino winters that followed a Nina (all three cold to very cold): -PDO weak Nino winters that followed a Nina (3 of 4 cool to cold; only 1951-2 warm..it had -PDO and +NAO) -PDO weak Nino winters that followed a Nina excluding 1951-2: I like 63-64 and 68-69 very much also and then you bring up stuff of legends:76-77. Link to comment Share on other sites More sharing options...
mitchnick Posted September 20, 2012 Author Share Posted September 20, 2012 fwiw, this morning's CFS2 is showing a real collapse of the NINO, though the CFS looks the same Link to comment Share on other sites More sharing options...
mattie g Posted September 20, 2012 Share Posted September 20, 2012 Cold and dry. Link to comment Share on other sites More sharing options...
Quixotic1 Posted September 20, 2012 Share Posted September 20, 2012 Jamstec Seasonal Forecast for September is out: http://www.jamstec.go.jp/frcgc/research/d1/iod/sintex_f1_forecast.html.en Coast to coast cold. Link to comment Share on other sites More sharing options...
Bob Chill Posted September 20, 2012 Share Posted September 20, 2012 Enso is pretty much a lock now. It's not going to hit mod and everything is pointing towards it waning as the winter progresses. I think we should start looking at the other factors that can help around here. We're getting close to Oct now so early signs of trends may start to show up. Anyone even remotely interested in the siberian snowcover theory needs to read this: http://www.nws.noaa....ohen_062211.pdf The snow cover is off to a good start: As stated in the thread in the main forum, it's too early to say whether the recent bump will hang around and build from here or is it transient. Snow cover is really easy to track. This link covers it: http://www.nohrsc.no...v/nh_snowcover/ Another thing that we need to keep our eye on is the ak vortex from hell that basically ruined our winter last year. There are signs that it may be shifting away from the position that it was stuck in last year. We have to pray that it doesn't return because it will singlehandedly kill our winter. Just a wag but I would have to assume the odds are on our side for that thing to set up shop elsewhere. I would imagine that it would be unusual for it stick in the same spot 2 winters in a row. Link to comment Share on other sites More sharing options...
MN Transplant Posted September 20, 2012 Share Posted September 20, 2012 Cold and dry. Still gets us snow. Link to comment Share on other sites More sharing options...
MDstorm Posted September 21, 2012 Share Posted September 21, 2012 Jamstec Seasonal Forecast for September is out: http://www.jamstec.go.jp/frcgc/research/d1/iod/sintex_f1_forecast.html.en Coast to coast cold. 180 degrees from what it was showing last month. The August outlook for the upcoming winter featured warm temps in Canada and in the western and central US. The coldest anomalies were along the east coast. The September outlook for the winter features cold temps in Canada and the western/central US. The only spots at or above normal are in the mid-Atlantic and the northeast. At least precip is above normal in the southeast and mid-Atlantic . Not exactly a "model" of consistency, though. MDstorm Link to comment Share on other sites More sharing options...
easternsnowman Posted September 21, 2012 Share Posted September 21, 2012 It's track record is not very good especially long range, but if you pick and choose august or sept one will be right....lol Link to comment Share on other sites More sharing options...
Huffwx Posted September 21, 2012 Share Posted September 21, 2012 When can we go "now cast" on winter outlooks? We do need to hear what KA has to say.. his outlooks are good "sometimes". Link to comment Share on other sites More sharing options...
Deck Pic Posted September 21, 2012 Share Posted September 21, 2012 The new model spread is quite tight....and consensus among dynamical models is 0.8..I think the 0.6 - 1.0 range is very likely with such a tight spread even 0.7-0.9 is a better target for DJF.....models do pretty well with ninos..ninas not as much...2008-09 was a debacle for models...very few saw the nina coming http://iri.columbia.edu/climate/ENSO/currentinfo/SST_table.html If we look back to the last 4 ninos, september consensus was very good... 02-03 1.0, actual 1.1 04-05 0.8, actual 0.6 06-07 0.9, actual 0.7 09-10 1.3, actual 1.6 Link to comment Share on other sites More sharing options...
mitchnick Posted September 21, 2012 Author Share Posted September 21, 2012 The new model spread is quite tight....and consensus among dynamical models is 0.8..I think the 0.6 - 1.0 range is very likely with such a tight spread even 0.7-0.9 is a better target for DJF.....models do pretty well with ninos..ninas not as much...2008-09 was a debacle for models...very few saw the nina coming http://iri.columbia..../SST_table.html If we look back to the last 4 ninos, september consensus was very good... 02-03 1.0, actual 1.1 04-05 0.8, actual 0.6 06-07 0.9, actual 0.7 09-10 1.3, actual 1.6 I'm not sayin' another 76/77, but I will say that that Sept. so far has been a pattern change with N/BN temps been a while since we could say that I know memory plays tricks on us, but this Sept. has a completely different feel than the last 2 after the 1st week Link to comment Share on other sites More sharing options...
Huffwx Posted September 22, 2012 Share Posted September 22, 2012 Umm, Isn't Keith Allen out there now? Link to comment Share on other sites More sharing options...
brad1551 Posted September 22, 2012 Share Posted September 22, 2012 The fading El Nino is probably due to the upward MJO pulse is currently over the western Pacific , and that is helping to lower the pressures closer to Darwin, Australia, and it is giving the appearance that El nino is weakening, when it actually is not, and with the MJO closer to Darwin, it is forcing lower pressures over that area, thus raising the SOI. The SOI also specifically focuses on the eastern Pacific, and with the SOI in positive territory, what that is signaling is the waters near and just west of the coast of South America are cooling, and this would mean that the waters over the central pacific closer to the international date line are remaining warm, if not warming even further, which just further supports the ideas that we’ve had that this El nino would be central pacific based, not like your typical El nino or La nina that is focused farther east over the pacific. However, I would not be too surprised to see the el nino weaken to warm neutral. Link to comment Share on other sites More sharing options...
ORH_wxman Posted September 22, 2012 Share Posted September 22, 2012 I'm not sayin' another 76/77, but I will say that that Sept. so far has been a pattern change with N/BN temps been a while since we could say that I know memory plays tricks on us, but this Sept. has a completely different feel than the last 2 after the 1st week The PDO looks almost the complete opposite of '76-'77 which makes me skeptical of a massive PNA ridge for most of the fall and into early winter. The Nino will try and spike the PNA at times, but the PDO- has been fighting the Nino all summer and early fall. Usually ENSO wins out in the end, but it might take awhile, and occasionally it doesn't win. Link to comment Share on other sites More sharing options...
Deck Pic Posted September 24, 2012 Share Posted September 24, 2012 Link to comment Share on other sites More sharing options...
GaWx Posted September 24, 2012 Share Posted September 24, 2012 As is being discussed in the N.E. forum, this does suggest some recent increase in the PDO due to both slight warming near the west coast of N.A. and the GOA as well as some new cooling near 40N, 170W. Yes, it does show a weaker Nino for now. However, I expect it to start warming back soon and this just about seals the deal for me that the fall/winter peak will be weak and not low end moderate. I do still expect at least five trimonthlies in a row of +0.5+ (based on the weeklies....I'm ignoring the current ONI table because it is so out of whack with the weeklies for MJJ and especially for JJA (NOAA/NCEP agrees)). For those who want a weak as opposed to moderate Nino peak, I see this map as good news. In terms of temperatures, if we get a -NAO for this DJF averaged and if the PDO can somehow get to +, I say look out below as the prospects for a really cold winter would be much higher than average. Even with snowfall, weak Ninos following La Ninas in DC have done pretty well overall with regard to the all important median and even pretty good with regard to the avg. per a post I made here a few days back. Then again, snowfall is more random than temperatures imo and, therefore is harder to predict. Link to comment Share on other sites More sharing options...
Deck Pic Posted September 24, 2012 Share Posted September 24, 2012 As is being discussed in the N.E. forum, this does suggest some recent increase in the PDO due to both slight warming near the west coast of N.A. and the GOA as well as some new cooling near 40N, 170W. Yes, it does show a weaker Nino for now. However, I expect it to start warming back soon and this just about seals the deal for me that the fall/winter peak will be weak and not low end moderate. I do still expect at least five trimonthlies in a row of +0.5+ (based on the weeklies....I'm ignoring the current ONI table because it is so out of whack with the weeklies for MJJ and especially for JJA (NOAA/NCEP agrees)). For those who want a weak as oposed to moderate Nino peak, I see this map as good news. In terms of temperatures, if we get a -NAO for this DJF averaged and if the PDO can somehow get to +, I say look out below as the prospects for a really cold winter would be much higher than average. Even with snowfall, weak Ninos following La Ninas in DC have done pretty well overall with regard to the all important median and even pretty good with regard to the avg. per a post I made here a few days back. Then again, snowfall is more random than temperatures imo and, therefore is harder to predict. which in this forum is precisely 0% of people Nice post though....median snow is a good bet Link to comment Share on other sites More sharing options...
Deck Pic Posted September 24, 2012 Share Posted September 24, 2012 Here is a list of the 8"+ events we have gotten in weak ninos: . Link to comment Share on other sites More sharing options...
mitchnick Posted September 24, 2012 Author Share Posted September 24, 2012 Here is a list of the 8"+ events we have gotten in weak ninos: . strange how that list of snowstorms is so similar to any predictions of 8" snow storms around here Link to comment Share on other sites More sharing options...
Huffwx Posted September 24, 2012 Share Posted September 24, 2012 strange how that list of snowstorms is so similar to any predictions of 8" snow storms around here Umm, either matt gave us a smack down or that list didn't load for me. I'm sure there has to be a few 8+ events. Link to comment Share on other sites More sharing options...
ORH_wxman Posted September 24, 2012 Share Posted September 24, 2012 Umm, either matt gave us a smack down or that list didn't load for me. I'm sure there has to be a few 8+ events. No, he's right. DCA has no 8"+ events in weak Ninos. The suburbs and other areas not too far away have had a few. Link to comment Share on other sites More sharing options...
WxUSAF Posted September 24, 2012 Share Posted September 24, 2012 Isn't all that warm water near Newfoundland, Labrador and Greenland fairly conducive to a -NAO? Isn't that JB's old rule of thumb (one of many...)? NPAC does look crappy though. New England can do the -PDO/-NAO thing alright, but usually it's naso good for us. Link to comment Share on other sites More sharing options...
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