frd Posted October 30, 2018 Share Posted October 30, 2018 This is of interest as to any relationship with the NAO and the type of El Nino ( Central vs Easter based ) Some, not here, state a -NAO is more likely in a West Pac or Central El Nino, but I believe here the research proves otherwise. Please note to fully grasp the relationship or lack ( trival in nature ) you need to read the complete study, very interesting as I said. I read the research but honestly do not recall if I missed anything on the phase change re the QBO or solar. This winter season I imagine those areas require careful consideration. Note : in the research many factors to come into play , for example the state of the Walk Cell., also all bets or off as Amy states, below, if there is a SSWW then -NAO probs might increase . Recent research https://journals.ametsoc.org/doi/10.1175/JCLI-D-16-0132.1 Only during CP El Niño winters with SSWs do the CMIP5 models simulate a negative AO pattern at the surface, although the coupling to the surface is weaker than during EP El Niño winters, particularly over Europe. This seems to be more related to the occurrence of SSWs than to the effect of CP events, as revealed by the frequency of occurrence of SSWs, which is not statistically different from the climatology in this case (at the 95% confidence level). This indicates that CP El Niño does not favor a perturbed stratosphere, whose most extreme manifestations are SSWs. Older research https://link.springer.com/article/10.1007/s00382-012-1570-2 Long model integrations suggest that the response to the two types of El Niño are similar in both the extratropical troposphere and stratosphere. Namely, both Central Pacific and Eastern Pacific El Niño lead to a deepened North Pacific low and a weakened polar vortex, and the effects are stronger in late winter than in early winter. However, the long experiments do indicate some differences between the two types of El Niño events regarding the latitude of the North Pacific trough, the early winter polar stratospheric response, surface temperature and precipitation over North America, and globally averaged surface temperature. These differences are generally consistent with, though smaller than, those noted in previous studies. Link to comment Share on other sites More sharing options...
Eskimo Joe Posted October 30, 2018 Share Posted October 30, 2018 I believe this year will be the first winter with the new NWS Hazard Simplification (HazSimp) for winter weather products. No more Blizzard Watches, instead everything will originate from a Winter Storm Watch then either a Winter Storm Warning, Ice Storm Warning or Blizzard Warning. Link to comment Share on other sites More sharing options...
clskinsfan Posted October 30, 2018 Share Posted October 30, 2018 3 hours ago, WinterWxLuvr said: Its obvious that the people making those maps don't understand where the mountains actually start. Snowfall west of Winchester is pretty much the same as it is in Winchester until you get well to the west. Move that 60-90 about 10 miles east and you have where the mountains are. Agreed. But that map has those of us west of town 10-20 inches above normal. I would take that in a heartbeat. Link to comment Share on other sites More sharing options...
nw baltimore wx Posted October 30, 2018 Share Posted October 30, 2018 1 hour ago, Eskimo Joe said: I believe this year will be the first winter with the new NWS Hazard Simplification (HazSimp) for winter weather products. No more Blizzard Watches, instead everything will originate from a Winter Storm Watch then either a Winter Storm Warning, Ice Storm Warning or Blizzard Warning. I posted a NWS survey in the banter thread yesterday regarding something similar to this, but I understood one of the options to be for everything that ends up being warned, it would come from a general Winter Storm Watch, then go under the classification of Winter Storm Warning for X. The X could be for blizzard conditions, accumulating snow, mix, or ice accumulations. I'm assuming they'd still have the advisory for storms that don't meet the warning criteria, but the idea is one warning for winter events and eliminate Blizzard Warnings and Ice Storm Warnings. I think that several Great Lakes weather offices have already discontinued the Lake Effect Snow Warning and now just use WSW. Link to comment Share on other sites More sharing options...
PrinceFrederickWx Posted October 30, 2018 Share Posted October 30, 2018 6 hours ago, clskinsfan said: Tucker Barnes and his team are with the snowy and late winter call as well. Nice write up from them by the way: http://www.fox5dc.com/weather/2018-2019-winter-outlook-for-dc-colder-snowier-winter-for-region#/ This map makes no sense for southern MD. I'm just saying... Link to comment Share on other sites More sharing options...
yoda Posted October 30, 2018 Share Posted October 30, 2018 1 minute ago, PrinceFrederickWx said: This map makes no sense for southern MD. I'm just saying... Because of the large range or something else? Link to comment Share on other sites More sharing options...
PrinceFrederickWx Posted October 30, 2018 Share Posted October 30, 2018 48 minutes ago, yoda said: Because of the large range or something else? I'm not sure why western Charles County would have so much more snow than the rest of us- that's never a climo cutoff. Most of southern MD averages 15-19" (except southern St. Mary's) yet everyone else outside of western Charles County is in the 8-18" range. That means they're forecasting above-normal snow for Charles, near or below normal for Calvert and much of St. Mary's, and anywhere from below normal to above normal for southern St. Mary's (given that range). It gets even more ridiculous if you start looking down by the tidewater and lower Delmarva- that would be well above average for most areas. Link to comment Share on other sites More sharing options...
WxUSAF Posted October 30, 2018 Author Share Posted October 30, 2018 I wouldn’t take these maps too literally. I think mets would be better served with text ranges because it’s clear they don’t (and probably shouldn’t) take too much effort to place contours. They are mostly trying to say “more N and W and less S and E” which is a obvious thing in our area. Link to comment Share on other sites More sharing options...
wxdude64 Posted October 30, 2018 Share Posted October 30, 2018 3 hours ago, clskinsfan said: Agreed. But that map has those of us west of town 10-20 inches above normal. I would take that in a heartbeat. I average 27 inches, they have me smack in the middle of 48-60...so they are saying double?? They should take psuhoff's advice. And I agree, if they are saying double, then double 'Shoe's and Canaan's and make a 200-300 line lol. Link to comment Share on other sites More sharing options...
WxUSAF Posted October 30, 2018 Author Share Posted October 30, 2018 I think if you focus on the 95 corridor and the cities where they are obviously focusing the message is 100-150% of normal for most of these public winter outlooks. Adjust as needed for your location with those percentages in mind. Link to comment Share on other sites More sharing options...
CAPE Posted October 30, 2018 Share Posted October 30, 2018 13 minutes ago, WxUSAF said: I think if you focus on the 95 corridor and the cities where they are obviously focusing the message is 100-150% of normal for most of these public winter outlooks. Adjust as needed for your location with those percentages in mind. Yeah this is the take away. Not much thought went into the subtleties of areas like the Delmarva or the far western highlands. They likely don't know/don't care. Link to comment Share on other sites More sharing options...
psuhoffman Posted October 30, 2018 Share Posted October 30, 2018 2 hours ago, WxUSAF said: I wouldn’t take these maps too literally. I think mets would be better served with text ranges because it’s clear they don’t (and probably shouldn’t) take too much effort to place contours. They are mostly trying to say “more N and W and less S and E” which is a obvious thing in our area. 1 hour ago, WxUSAF said: I think if you focus on the 95 corridor and the cities where they are obviously focusing the message is 100-150% of normal for most of these public winter outlooks. Adjust as needed for your location with those percentages in mind. I agree with both. And this isn't a big deal. I don't care much or lose sleep over this. But it's always struck me as bad form to have a map and be so sloppy with the edges. If your not going to put any effort into making PA or WV accurate then why not just zoom the map in and not have them at all? It's no big deal but I've never understood it. It also seems worse in the D.C. area. When I lived in the Philly, Scranton/Wilkes Barre or State College PA markets they didn't seem as bad. Their maps would only cover the area they were giving a legit forecast for. Often the map wouldn't even be a square and would simply include the counties in their viewing area and it was obvious they put effort into the whole area. Not sure why the D.C. and Baltimore outlets put out these huge area maps then only bother with the viewing area. Just seems silly but maybe I'm crazy! Link to comment Share on other sites More sharing options...
mattie g Posted October 31, 2018 Share Posted October 31, 2018 11 minutes ago, psuhoffman said: I agree with both. And this isn't a big deal. I don't care much or lose sleep over this. But it's always struck me as bad form to have a map and be so sloppy with the edges. If your not going to put any effort into making PA or WV accurate then why not just zoom the map in and not have them at all? It's no big deal but I've never understood it. It also seems worse in the D.C. area. When I lived in the Philly, Scranton/Wilkes Barre or State College PA markets they didn't seem as bad. Their maps would only cover the area they were giving a legit forecast for. Often the map wouldn't even be a square and would simply include the counties in their viewing area and it was obvious they put effort into the whole area. Not sure why the D.C. and Baltimore outlets put out these huge area maps then only bother with the viewing area. Just seems silly but maybe I'm crazy! It’s ugly to have a map that just ends as a block at the far reaches of your viewing area. Besides, it can make those areas appear to be unimportant (which they are...let’s be fair ) by being on the edges. If you expand the map to show areas outside the viewing area, by default you include in the heart of the map those at the edge of the viewing area. Link to comment Share on other sites More sharing options...
psuhoffman Posted October 31, 2018 Share Posted October 31, 2018 45 minutes ago, mattie g said: It’s ugly to have a map that just ends as a block at the far reaches of your viewing area. Besides, it can make those areas appear to be unimportant (which they are...let’s be fair ) by being on the edges. If you expand the map to show areas outside the viewing area, by default you include in the heart of the map those at the edge of the viewing area. Interesting take...i wonder why the smaller markets didn't seem to do that. More humble maybe? Lol Link to comment Share on other sites More sharing options...
mattie g Posted October 31, 2018 Share Posted October 31, 2018 30 minutes ago, psuhoffman said: Interesting take...i wonder why the smaller markets didn't seem to do that. More humble maybe? Lol Big cities are more liberal, thus more inclusive. Link to comment Share on other sites More sharing options...
wxdude64 Posted October 31, 2018 Share Posted October 31, 2018 1 hour ago, mattie g said: Big cities are more liberal, thus more inclusive. 'They' may be more inclusive, but definitely have no idea what they are doing that far out, still agree with psu. Link to comment Share on other sites More sharing options...
nj2va Posted October 31, 2018 Share Posted October 31, 2018 They aren't even trying out in the western highlands on that map. With the general call of above normal snow across the whole region, places like Canaan should be pushing 200.I thought the same. Avg in McHenry is 105-110” yet they’re calling for 60-90” in an otherwise AN winter. Canaan would be close to 200” for sure. Link to comment Share on other sites More sharing options...
frd Posted October 31, 2018 Share Posted October 31, 2018 Whether this Euro forecast for snowfall is is even close to being accurate and reality , if there is that much snow North and Northwest of us we are going to shiver at some point. Wow, to the snow cover and the the depth of the snow in Eastern Canada. We are putting down the pathway for cold air with little moderation if we get the right pattern later in the winter, or sooner. Link to comment Share on other sites More sharing options...
Wxdavis5784 Posted October 31, 2018 Share Posted October 31, 2018 16 hours ago, PrinceFrederickWx said: This map makes no sense for southern MD. I'm just saying... I agree. It’s really only the extreme southern parts of St. Mary’s and Calvert where totals drastically drop as you head down. I grew up in Northern St. Mary’s county on the Charles County line and we typically did just as well as everyone near the city. It’s a huge misconception about how little snow we get. Do we get as much as the mountains or even upper Montgomery? No. But I can tell you as a native southern Marylander I’ve seen it go from 6” at my house to zippy about 15 min south of there. The One thing we typically battle with strong coastal lows is the mixing of sleet at times which can diminish overall accumulations depending on the track. Link to comment Share on other sites More sharing options...
Maestrobjwa Posted October 31, 2018 Share Posted October 31, 2018 Okay, so...is this officially gonna be a Modoki El Niño this year? If so...I wanna ask about why some of the weak Modoki's we've had the last 60+ years failed...(like 1952/53, 58/59 76-77, 94/95, 04-05,) Link to comment Share on other sites More sharing options...
psuhoffman Posted October 31, 2018 Share Posted October 31, 2018 17 minutes ago, Maestrobjwa said: Okay, so...is this officially gonna be a Modoki El Niño this year? If so...I wanna ask about why some of the weak Modoki's we've had the last 60+ years failed...(like 1952/53, 58/59 76-77, 94/95, 04-05,) 52/53, 58/59, and 76/77 aren't listed as modoki nino's on the two sources I used to identify modoki years. 53 and 59 were listed as a neutral years 77 was a traditional nino 92 and 95 were modoki nino's and were complete failures 05 was a modoki and like most modoki's mid January through March featured a pretty good pattern and we did recover to an average snowfall winter but just got a little unlucky not to get a flush hit from any storm. A couple just missed, and a couple had big time potential but ended up only being moderate storms and didnt get their act together. I am about to do a longer post regarding what the analogs indicate regarding this winter. Not necessarily a prediction just a "what does the data show". Link to comment Share on other sites More sharing options...
psuhoffman Posted October 31, 2018 Share Posted October 31, 2018 41 minutes ago, Maestrobjwa said: Okay, so...is this officially gonna be a Modoki El Niño this year? If so...I wanna ask about why some of the weak Modoki's we've had the last 60+ years failed...(like 1952/53, 58/59 76-77, 94/95, 04-05,) I went back and did some digging on 1953 and 59... both peaked at +0.6 on the ONI scale. This is borderline weak nino status, but many data sources don't list a nino unless it reaches .7 for a seasonal ONI. NCEP now lists a nino as + or - .5 which means very few neutral years and a much lower threshold to get an enso event. I am not sure including such borderline events is really pertinent as we are already at a monthly value near 1 and almost all guidance suggests this nino event peaks around December somewhere between +.8 and +1.4 with a mean near +1 on the guidance. If this event totally collapses then some of those borderline neutral/very weak nino events could become better analogs, but on the other hand there are lots of factors that could change that would change the analogs in other ways, we have to go with some kind of expected state to eliminate years. But there were other weak modoki years where the results were good as I will show in the data I compiled so I am not sure it matters much. Link to comment Share on other sites More sharing options...
frd Posted October 31, 2018 Share Posted October 31, 2018 2 hours ago, Maestrobjwa said: Okay, so...is this officially gonna be a Modoki El Niño this year? If so...I wanna ask about why some of the weak Modoki's we've had the last 60+ years failed...(like 1952/53, 58/59 76-77, 94/95, 04-05,) Some mets actually say that this will be a hybird Nino . Meaning they think the warmer SSTs will also be located in the Eastern regions as well. Eh, I was looking at the latest SSTs and I am not so sure about that. And, as you can see above from @psuhoffman not even a Modaki is a sure win for an awesome winter. @bluewave mentioned in the NY thread that the SST profile and atmospheric response is still a battling combination of Nina and Nino. He also mentioned this might be the reason for the huge changes in the models. Any one with a seasonal forecast this year is really going to face a challenge. I read Judah Cohen this morning and he posted the CFS and he showed the model with a pattern for December ( cough, cough ) that is a classic El Nino . Looked great by the way. Link to comment Share on other sites More sharing options...
psuhoffman Posted October 31, 2018 Share Posted October 31, 2018 So I decided to compile some data for the winter and just see what it suggests. We have discussed all this before I just wanted to put it all together. This is all obviously subjective but I started with looking for enso years that were somewhat close since we know that is one of the most significant driving factors on the pattern AND its one that we can predict with reasonable accuracy now from this range. So we are expecting a central based enso event that will probably peak with an ONI somewhere near 1 for the winter months. So lets give ourselves a leeway of .3 plus or minus that and identify central based events that peaked with a winter ONI value between .7 and 1.3, and that gives us 8 seasons. A reasonable sample size. The winters of (using January as the year) 1964, 1969, 1978, 1987, 1995, 2003, 2005, and 2015. If somehow this event ends up stronger then expected the years of 1958, 1966, 1992 and 2010 become enso analogs. I am not totally sure how much the strength matters versus where the forcing is. This is partially because I found the 4 years that were stronger still had many of the same tendencies as the weaker ones. You will see that below. So before we start to break the analogs down even more by additional factors there is a pretty clear overall tendency in those years. If we look at all 12 modoki nino's since 1950, 8 were above normal snowfall. 2 were about average. And 2 were total crap. So just using modoki nino we would have a 67% chance of above normal snowfall. 17% normal and 17% below. What if we narrow it down to the 8 ninos similar in location AND strength. Then we get 5 above normal, 2 near normal, and 1 dud (1995). That gives us 63% chance at above normal snowfall, 25% chance of normal, 13% chance below. Considering the small sample size that isn't a significant difference in our odds. Furthermore the characteristics of the seasons were similar among the sample of stronger modoki nino's as the weaker ones. 3/4 of the stronger ones were good winters. 5/8 of the weaker ones were. And the seasonal variance and how they got there was similar. The good years featured help in the north pacific from either an Aleutian low or an epo ridge and blocking over the top. The two dud winters (one from each set) featured little help in the north Pacific AND a raging positive AO/NAO that pretty much ruined the winter. There was also a tendency to finish strong. A few years had early starts, but except for the dud's they all had strong second halfs with a snowy period sometime in January/February. So some started bad then recovered. The ones that started with snow in December all went on to be blockbuster years. So a good start would be a very good sign, but a bad start doesnt mean we are doomed a few years in our analog set had no snow before January and went on to be good years like 1978, 1987, and 2015. However on the down side having a bad start does open the door to 1995 being an analog. So what if we try to narrow down the analogs by other factors. Here is where it gets tricky. I can look at the factors but I have no idea which is actually most important in any given year. There are a lot of conflicting signals. But if we take the 8 best enso matches this is how they fit in for other factors like qbo, and solar. I ranked the matches based on similarity of enso, QBO phase and solar. The snowfall is for BWI 1964: ONI 1.3, QBO was very similar, also a low solar year. GREAT MATCH BWI Snowfall: 51.8" 1995: ONI 1.1, QBO almost identical, Also a low solar year, GREAT MATCH BWI snowfall 8.2 1978: ONI .8, QBO almost identical to this year, Solar was average, GOOD MATCH BWI snowfall 34.3 1969: ONI 1.1, QBO was somewhat similar but the flip happened later, Solar was a bad match, Decent Match BWI snowfall 18.6" 2005: ONI .7, QBO similar value but opposite phase flip, Solar medium, Decent Match BWI snowfall 18" 1987: ONI 1.2, QBO was almost opposite of now, Also a low solar year, Decent Match BWI snowfall 35.2 2003: ONI 1.1, QBO similar value but during the opposite phase flip, Solar high, Decent Match BWI snowfall 58.1 2015: ONI .7, QBO not a good match, Solar not a good match, weak Match overall BWI snowfall 28.7" So the best matches were 1964 and 1995. 1978 was also a very good match. That doesn't really help because the two best matches were almost total opposites. I wish I could say for sure what made 1995 be the lone bad outlier. I can say the SST's that year in the north pacific were almost opposite right now and most of the other years since 1984. The problem is I cannot compare 1995 to 1978 or 1964 the other closest matches because I cannot find good SST data for those years. If someone has that information I would gladly do the comparison. But given what I have to look at those two years seem very similar. As for what went wrong in 1995 compared to the others. It seems clear in the set that there is a high frequency of both a favorable north pacific pattern that features lower hights near and south of the Aleutians and an EPO ridge. There is also a high prevalence of NAO blocking. Some of those years only had one or the other but that was able to compensate for the lack of the other. 1992 and 1995 were the only years in the 12 year set where neither established at any point in the winter and so the whole year was crap. I would say the thing we want to look out for, if we start to see lower heights setting up over Alaska and a raging positive NAO going into December, that would be a sign we are heading towards 1992 and 1995. That was the characteristic of those fails. Having a warm December but with ambiguous patterns in those areas would be more similar to the years we recovered later. As for the worry by some about a weak modoki being worse...the data just doesn't indicate that. 1978 only peaked with an ONI of .8 which is below where we are expected to peak. 2003 was only 1.1 and 2015 only peaked at .7. 1995, the worst case peaked at 1.1 so it was stronger then some of the better years. And the other total dud 1992 peaked at 1.7 on the ONI. Because it's such a small sample size one year can skew things and that is probably what is happening on the correlations that say weaker is worse... because just looking at the years and the results it doesn't seem to indicate that. So what do I take out of this... Well first of all 8/12 and 5/8 doesn't guarantee us anything. 1992 and 1995 happened and are a cautionary tale. 2005 is another cautionary tale, the second half of that year featured a good pacific and Atlantic pattern and could easily have been another 1958 or 2015 type ending but we just didn't get lucky. But we did get snow so it wasnt a disaster. But these probabilities are almost the exact opposite of what we were dealing with the last 2 years when I broke down the analogs and we were left praying for that fluke year or two that was good in the set. This year any way you slice it the majority of years are good. So while we have to wait and see how this is evolving, and make sure some crazy shift in the expected pattern isnt taking place, I like where we are right now way more then where we were heading into the last few winters. Link to comment Share on other sites More sharing options...
CAPE Posted October 31, 2018 Share Posted October 31, 2018 CFS finally has hit on the right h5 look for January. Of course if you invert everything you see on this panel, that will probably be it's solution for the same period in another week lol. Link to comment Share on other sites More sharing options...
WxUSAF Posted October 31, 2018 Author Share Posted October 31, 2018 Raleighwx’s winter outlook: http://raleighwxmodels.com/awhuffma/Winter/Winter2018-19Forecast.pdf going with a generally cold snowier than average winter. Backloaded. Link to comment Share on other sites More sharing options...
AfewUniversesBelowNormal Posted October 31, 2018 Share Posted October 31, 2018 El Nino is really impacting right now. Link to comment Share on other sites More sharing options...
Maestrobjwa Posted November 1, 2018 Share Posted November 1, 2018 7 hours ago, psuhoffman said: So I decided to compile some data for the winter and just see what it suggests. We have discussed all this before I just wanted to put it all together. This is all obviously subjective but I started with looking for enso years that were somewhat close since we know that is one of the most significant driving factors on the pattern AND its one that we can predict with reasonable accuracy now from this range. So we are expecting a central based enso event that will probably peak with an ONI somewhere near 1 for the winter months. So lets give ourselves a leeway of .3 plus or minus that and identify central based events that peaked with a winter ONI value between .7 and 1.3, and that gives us 8 seasons. A reasonable sample size. The winters of (using January as the year) 1964, 1969, 1978, 1987, 1995, 2003, 2005, and 2015. If somehow this event ends up stronger then expected the years of 1958, 1966, 1992 and 2010 become enso analogs. I am not totally sure how much the strength matters versus where the forcing is. This is partially because I found the 4 years that were stronger still had many of the same tendencies as the weaker ones. You will see that below. So before we start to break the analogs down even more by additional factors there is a pretty clear overall tendency in those years. If we look at all 12 modoki nino's since 1950, 8 were above normal snowfall. 2 were about average. And 2 were total crap. So just using modoki nino we would have a 67% chance of above normal snowfall. 17% normal and 17% below. What if we narrow it down to the 8 ninos similar in location AND strength. Then we get 5 above normal, 2 near normal, and 1 dud (1995). That gives us 63% chance at above normal snowfall, 25% chance of normal, 13% chance below. Considering the small sample size that isn't a significant difference in our odds. Furthermore the characteristics of the seasons were similar among the sample of stronger modoki nino's as the weaker ones. 3/4 of the stronger ones were good winters. 5/8 of the weaker ones were. And the seasonal variance and how they got there was similar. The good years featured help in the north pacific from either an Aleutian low or an epo ridge and blocking over the top. The two dud winters (one from each set) featured little help in the north Pacific AND a raging positive AO/NAO that pretty much ruined the winter. There was also a tendency to finish strong. A few years had early starts, but except for the dud's they all had strong second halfs with a snowy period sometime in January/February. So some started bad then recovered. The ones that started with snow in December all went on to be blockbuster years. So a good start would be a very good sign, but a bad start doesnt mean we are doomed a few years in our analog set had no snow before January and went on to be good years like 1978, 1987, and 2015. However on the down side having a bad start does open the door to 1995 being an analog. So what if we try to narrow down the analogs by other factors. Here is where it gets tricky. I can look at the factors but I have no idea which is actually most important in any given year. There are a lot of conflicting signals. But if we take the 8 best enso matches this is how they fit in for other factors like qbo, and solar. I ranked the matches based on similarity of enso, QBO phase and solar. The snowfall is for BWI 1964: ONI 1.3, QBO was very similar, also a low solar year. GREAT MATCH BWI Snowfall: 51.8" 1995: ONI 1.1, QBO almost identical, Also a low solar year, GREAT MATCH BWI snowfall 8.2 1978: ONI .8, QBO almost identical to this year, Solar was average, GOOD MATCH BWI snowfall 34.3 1969: ONI 1.1, QBO was somewhat similar but the flip happened later, Solar was a bad match, Decent Match BWI snowfall 18.6" 2005: ONI .7, QBO similar value but opposite phase flip, Solar medium, Decent Match BWI snowfall 18" 1987: ONI 1.2, QBO was almost opposite of now, Also a low solar year, Decent Match BWI snowfall 35.2 2003: ONI 1.1, QBO similar value but during the opposite phase flip, Solar high, Decent Match BWI snowfall 58.1 2015: ONI .7, QBO not a good match, Solar not a good match, weak Match overall BWI snowfall 28.7" So the best matches were 1964 and 1995. 1978 was also a very good match. That doesn't really help because the two best matches were almost total opposites. I wish I could say for sure what made 1995 be the lone bad outlier. I can say the SST's that year in the north pacific were almost opposite right now and most of the other years since 1984. The problem is I cannot compare 1995 to 1978 or 1964 the other closest matches because I cannot find good SST data for those years. If someone has that information I would gladly do the comparison. But given what I have to look at those two years seem very similar. As for what went wrong in 1995 compared to the others. It seems clear in the set that there is a high frequency of both a favorable north pacific pattern that features lower hights near and south of the Aleutians and an EPO ridge. There is also a high prevalence of NAO blocking. Some of those years only had one or the other but that was able to compensate for the lack of the other. 1992 and 1995 were the only years in the 12 year set where neither established at any point in the winter and so the whole year was crap. I would say the thing we want to look out for, if we start to see lower heights setting up over Alaska and a raging positive NAO going into December, that would be a sign we are heading towards 1992 and 1995. That was the characteristic of those fails. Having a warm December but with ambiguous patterns in those areas would be more similar to the years we recovered later. As for the worry by some about a weak modoki being worse...the data just doesn't indicate that. 1978 only peaked with an ONI of .8 which is below where we are expected to peak. 2003 was only 1.1 and 2015 only peaked at .7. 1995, the worst case peaked at 1.1 so it was stronger then some of the better years. And the other total dud 1992 peaked at 1.7 on the ONI. Because it's such a small sample size one year can skew things and that is probably what is happening on the correlations that say weaker is worse... because just looking at the years and the results it doesn't seem to indicate that. So what do I take out of this... Well first of all 8/12 and 5/8 doesn't guarantee us anything. 1992 and 1995 happened and are a cautionary tale. 2005 is another cautionary tale, the second half of that year featured a good pacific and Atlantic pattern and could easily have been another 1958 or 2015 type ending but we just didn't get lucky. But we did get snow so it wasnt a disaster. But these probabilities are almost the exact opposite of what we were dealing with the last 2 years when I broke down the analogs and we were left praying for that fluke year or two that was good in the set. This year any way you slice it the majority of years are good. So while we have to wait and see how this is evolving, and make sure some crazy shift in the expected pattern isnt taking place, I like where we are right now way more then where we were heading into the last few winters. Great analysis as usual! Now I've got a few questions: So...what exactly is the QBO now? (and where do we need it?) And what influence does that have on the AO? (And if the QBO doesn't help the AO go negative, what else can?) I saw in another analysis that El Niño winters with a positive QBO didn't have a lot of analogs (that was the an analysis from Raleighwx) (And speaking of that...so I take it there's no sure way to tell at this moment what the AO/NAO will do a month from now?) But overall...I guess that NAO will be the point of greatest interest? (Now that the Niño is practically here?) And that's really crazy that the two best matches for where we are right now had polar opposite results, lol Link to comment Share on other sites More sharing options...
raindancewx Posted November 1, 2018 Share Posted November 1, 2018 1963-64 had a major VEI eruption, and 1994-95 was a recovery year from a major VEI eruption (Pinatubo effect wore off), both in the Tropics. The background conditions for the prior winters (1962-63 and 1993-94) and actual weather in those two years are quite similar nationally. Agung erupted in 1963. For what its worth, in 3/1963 the AMO had been warm for decades, then it cooled. Last year...Agung erupted. Guess what happened? AMO dramatically cooled. Yeah, it could be a coincidence, but it is interesting. Link to comment Share on other sites More sharing options...
Maestrobjwa Posted November 1, 2018 Share Posted November 1, 2018 21 minutes ago, raindancewx said: 1963-64 had a major VEI eruption, and 1994-95 was a recovery year from a major VEI eruption (Pinatubo effect wore off), both in the Tropics. The background conditions for the prior winters (1962-63 and 1993-94) and actual weather in those two years are quite similar nationally. Agung erupted in 1963. For what its worth, in 3/1963 the AMO had been warm for decades, then it cooled. Last year...Agung erupted. Guess what happened? AMO dramatically cooled. Yeah, it could be a coincidence, but it is interesting. But wait...last year's eruption wasn't nearly strong enough to influence anything, right? And when did this dramatic cooling of the AMO occur?... Link to comment Share on other sites More sharing options...
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