BethesdaWX Posted January 17, 2012 Share Posted January 17, 2012 Alaska is having it's coldest winter in over 40 year thus far, very impressive. Link to comment Share on other sites More sharing options...
donsutherland1 Posted January 17, 2012 Share Posted January 17, 2012 Alaska is having it's coldest winter in over 40 year thus far, very impressive. IMO, it remains a fairly high confidence idea that February will also be cold in Alaska. Link to comment Share on other sites More sharing options...
donsutherland1 Posted January 18, 2012 Share Posted January 18, 2012 Speaking further about long-range forecasting: For the month ahead, I run a variety of scenarios on a regular basis (usually weekly, sometimes more frequently as the month in question approaches). Here's a comparison of what I came up with for the weeks beginning January 9 and January 16. At the bottom, I also compared the 1/17 CFSv2 forecast for February and also provided a table of the observed change in temperatures for February over the past decade. The observed change in decadal temperatures helps me adjust my thinking e.g., for January, it suggested that cool anomalies would be confined to the Pacific Northwest and possibly Florida (Lower 48 States). As noted previously, I continue to expect the East to come out warmer than normal in February/perhaps Western half or third colder than normal. However, it is a close call with coast-to-coast warmth. Later data seems to lean in that direction, as does the CFSv2. IMO, the latter chart showing a warm Alaska is suspect in that area given my expectations for a predominant EPO+. Finally, it should be noted that I draw from multiple years. However, in the first chart, 1956 was perhaps the best analog. In the second, 1976 was the best one. By "best," I mean the year for which the most dates showed up. From now to near the end of January, things can still change. I very much hope that they will. Link to comment Share on other sites More sharing options...
BethesdaWX Posted January 18, 2012 Share Posted January 18, 2012 Long-range forecasting is very challenging and a high degree of "art." Having said that, December was very consistent with a pattern one would expect from an extreme AO+ month. The December 2011 anomalies are on the left and the composite based on the AO is on the right: Also, from my perspective, January has not been "highly abnormal." IMO, it has largely been what would be expected given the evolution of the ENSO, AO+, PNA neutral, and EPO+. The raw charts show January (top) and February (bottom) for my assumptions: NOTE: These charts are not adjusted for the observed warming that has been occurring in recent decades. The proper adjustment for January would be to confine the cool anomalies to the Pacific Northwest and to forecast the Northern Plains and New England to be warmer than normal. Florida would also be adjusted to somewhat cooler than shown on the map. In February, the cold should be sufficient to overwhelm the observed warming in the Northern Plains. For another perspective, here's the latest forecast for February from the CFSv2: February is not yet locked in. There remains a prospect of coast-to-coast warmth. It is a close call, though I lean against it at present. IMO, what might have proved confusing was the two modeled stratospheric warming events. The assumption was that each would be of a magnitude to disrupt or even split the polar vortex, leading to strong blocking. Neither event reached that magnitude. The minor events have resulted in a modest weakening of the polar vortex. The decay due to other factors has also been ongoing. Hence, a period of blockiness may lie ahead, but it probably won't be sufficient to overwhelm the other teleconnections (PNA and EPO). My February map assumes a modestly negative AO for the month as a whole. A positive AO would lead to a warmer outcome and, as noted above, it is a very close call. I agree with you in that one would expect the warm pattern in a +AO, but determining the length I think has been harder to do in recent years. As for your February map, is the +EPO/COD expectations statistically based? I guess the climo thing is the difference, I think given where the higher heights are progged to be over the next few weeks that a west based -NAO would be the outcome once the MJO begins to move. Link to comment Share on other sites More sharing options...
donsutherland1 Posted January 18, 2012 Share Posted January 18, 2012 I agree with you in that one would expect the warm pattern in a +AO, but determining the length I think has been harder to do in recent years. As for your February map, is the +EPO/COD expectations statistically based? For me, the first guess at the EPO idea is based on statistics and correlations. As the month draws closer, ensemble guidance carries much greater weight. As noted earlier, my first guess for February is probably a negative to neutral AO.There is some extended range ensemble support for such an idea at the beginning of February. Statistics also play a role based on past long-duration mainly/wholly AO+ regimes. The ensembles will carry greater weight as the month approaches. Link to comment Share on other sites More sharing options...
easternsnowman Posted January 18, 2012 Share Posted January 18, 2012 Statistics can only go so far, they did'nt work too well the last 2 winters. Link to comment Share on other sites More sharing options...
donsutherland1 Posted January 18, 2012 Share Posted January 18, 2012 Statistics can only go so far, they did'nt work too well the last 2 winters. Probabilities allow one to assess uncertainty. Forecasting is a highly probabilistic exercise. Certainty is not the typical condition. Statistics provide insight. And yes, the extreme AO- (2009-10 and 2010-11) overwhelmed the pattern in El Niño and La Niña winters. The Northern Hemisphere temperature anomalies best fit that kind of extreme event. Moreover, similar to 1957-58 when a moderate/strong El Niño coincided with strong blocking, there were multiple KU snowstorms. Similar pre-1950 combinations of moderate La Niña events-strong blocking e.g., 1909-10, witnessed multiple KU-type snowstorms. Probabilities give insight. They do not give the entire answer, but they do beat treating scenarios as random events. Assumptions are key. Wrong assumptions lead to wrong solutions. Dr. Judah Cohen nailed the temperature anomalies for winters 2009-10 and 2010-11 by making the correct assumption concerning the predominant AO state during those winters. His finding some correlation between October Eurasian snowcover and the winter AO state has been published in a number of papers. Link to comment Share on other sites More sharing options...
easternsnowman Posted January 18, 2012 Share Posted January 18, 2012 Probabilities allow one to assess uncertainty. Forecasting is a highly probabilistic exercise. Certainty is not the typical condition. Statistics provide insight. And yes, the extreme AO- (2009-10 and 2010-11) overwhelmed the pattern in El Niño and La Niña winters. The Northern Hemisphere temperature anomalies best fit that kind of extreme event. Moreover, similar to 1957-58 when a moderate/strong El Niño coincided with strong blocking, there were multiple KU snowstorms. Similar pre-1950 combinations of moderate La Niña events-strong blocking e.g., 1909-10, witnessed multiple KU-type snowstorms. Probabilities give insight. They do not give the entire answer, but they do beat treating scenarios as random events. Assumptions are key. Wrong assumptions lead to wrong solutions. Dr. Judah Cohen nailed the temperature anomalies for winters 2009-10 and 2010-11 by making the correct assumption concerning the predominant AO state during those winters. His finding some correlation between October Eurasian snowcover and the winter AO state has been published in a number of papers. Yes I agree when we have an extrene AO whether positive or negative that does seem to dominate all other indices and enso too. Link to comment Share on other sites More sharing options...
BethesdaWX Posted January 18, 2012 Share Posted January 18, 2012 Yes I agree when we have an extrene AO whether positive or negative that does seem to dominate all other indices and enso too. If there is a deep -PNA and -AO present simultaniously you'll still be warm. Link to comment Share on other sites More sharing options...
easternsnowman Posted January 18, 2012 Share Posted January 18, 2012 If there is a deep -PNA and -AO present simultaniously you'll still be warm. Maybe 1 or 2 above normal as opposed to 5 above. It also will also depend which one is more negative and of course if the nao is negative also. Link to comment Share on other sites More sharing options...
NEOH Posted January 19, 2012 Share Posted January 19, 2012 Feb will be rocking according to JB... just like December and January I assume. "On table:Feb 2012 as nasty asDec 2010..worst case (3-4 wks from now longer term pattern has similarities to 1985 mid/late Jan cold wave)" Link to comment Share on other sites More sharing options...
Chris L Posted January 19, 2012 Share Posted January 19, 2012 Feb will be rocking according to JB... just like December and January I assume. "On table:Feb 2012 as nasty asDec 2010..worst case (3-4 wks from now longer term pattern has similarities to 1985 mid/late Jan cold wave)" I suppose there will be a HECS in February according to JB. Link to comment Share on other sites More sharing options...
uncle W Posted January 19, 2012 Share Posted January 19, 2012 I've been on the February train since November...We are gradually getting colder and we could have a cold February with normal snowfall...1949-50 was one of those years with a mild December and January but had a cold February despite a negative pna and positive ao/nao...It won't take much for February to be the coldest month especially if the January thaw comes Monday... Link to comment Share on other sites More sharing options...
buckeye Posted January 20, 2012 Share Posted January 20, 2012 Feb will be rocking according to JB... just like December and January I assume. "On table:Feb 2012 as nasty asDec 2010..worst case (3-4 wks from now longer term pattern has similarities to 1985 mid/late Jan cold wave)" It's unbelievable that he continues this kind of rhetoric over and over again only to be horribly wrong over and over again. Not an ounce of humility in the face of serial failure. Why is he doing this to himself, (his reputation)? Apparently weenie followers must be all he has. Link to comment Share on other sites More sharing options...
Brian5671 Posted January 20, 2012 Share Posted January 20, 2012 If JB is right about Feb this is a coup on his part. He finally got an individual storm call right as his Tue call for Sat's event looks right on the money...let's see if he can nail the pattern for Feb....although his seasonal winter call has a blowtorch for February.... Link to comment Share on other sites More sharing options...
HeatMiser Posted January 20, 2012 Share Posted January 20, 2012 The best part about this thread is that the title has been appropriate for the last 3 months Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted January 20, 2012 Share Posted January 20, 2012 If JB is right about Feb this is a coup on his part. He finally got an individual storm call right as his Tue call for Sat's event looks right on the money...let's see if he can nail the pattern for Feb....although his seasonal winter call has a blowtorch for February.... I would hope someone could nail a 4-5 day forecast who is a professional met. If your refering to the snow event currently in Chicago. That is very easy. I mean come on. Link to comment Share on other sites More sharing options...
usedtobe Posted January 20, 2012 Share Posted January 20, 2012 I would hope someone could nail a 4-5 day forecast who is a professional met. If your refering to the snow event currently in Chicago. That is very easy. I mean come on. There are plenty of times when a professional met can't hit a forecast 4-5 days in advance because of chaos. I'm not a fan of JB and am not defending him as he makes many deterministic calls that he should not be so aggressive on and because of that he has busted more often than he really needed to. Still hitting a 4 or 5 day forecast is not that easy at least for me. Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted January 20, 2012 Share Posted January 20, 2012 There are plenty of times when a professional met can't hit a forecast 4-5 days in advance because of chaos. I'm not a fan of JB and am not defending him as he makes many deterministic calls that he should not be so aggressive on and because of that he has busted more often than he really needed to. Still hitting a 4 or 5 day forecast is not that easy at least for me. That is the not the point. I agree with you. It is not easy. We just had tornadoes arouind here that no one called. One of the most epic busts in STL ever. The TV Mets all went off the air hours before the event saying showers and maybe some thunder showers no severe. The NWS had no mention of it. So a 4-5 day forecast, expecially in the cold season can be hard to nail down. I was more or less refering to the posters defending of JB by using him nailing the shortwave zipping acrross the CONUS in the zonal flow that has arctic air to tap to defend him when it's just one relatively easy forecast. It's not like JB was predicting a phasing event that the models didn't have major aggrement on days before Tuesday. It distorts how absurd this JB is and gives him credibility where he should have zero at this point. As Buckeye wrote how can he have anyone take him serious. I have seen 30-40 posts since November on our local(St. Louis) weather blog which has thousands of followers and hundreds of posters post JBs predictions and hang on this guy for hope for winter. When he is really a snake oil sales man at this point. Busting a forecast like local legendary Met Dave Murray did in December is one thing. By Jan 5th Dave came on our blog for the first time ever and admitted he blew it. And basically said things didn't work out and this winter turned out warm and pulled back, admited being gun shy, even said he will check over his stuff to see where he missed. That takes integridy. I think that is respectable and Dave will be a better met, even after 30+ years for it. this JB plays on the oxytocin induced religious like nature of winter weather weenies. And it's sad. Link to comment Share on other sites More sharing options...
SpartyOn Posted January 20, 2012 Share Posted January 20, 2012 Don't even know why we are wasting thread space on this guy. Link to comment Share on other sites More sharing options...
Coach McGuirk Posted January 21, 2012 Share Posted January 21, 2012 Don't even know why we are wasting thread space on this guy. Ji or JB? Either way, you're probably right. Link to comment Share on other sites More sharing options...
Ottawa Blizzard Posted January 26, 2012 Share Posted January 26, 2012 JB now seems to think February will average 2 degrees F below normal across the northern tier with bitter cold during the run-up to Valentine's Day. DT, by contrats, thinks this winter is toast. Link to comment Share on other sites More sharing options...
Brian5671 Posted January 26, 2012 Share Posted January 26, 2012 JB now seems to think February will average 2 degrees F below normal across the northern tier with bitter cold during the run-up to Valentine's Day. DT, by contrats, thinks this winter is toast. The way its gone, I'd go with toast. Link to comment Share on other sites More sharing options...
mempho Posted January 26, 2012 Share Posted January 26, 2012 The way its gone, I'd go with toast. Winter is over. X Link to comment Share on other sites More sharing options...
Feb Posted January 26, 2012 Share Posted January 26, 2012 Winter is over. X Y? Link to comment Share on other sites More sharing options...
Ottawa Blizzard Posted January 28, 2012 Share Posted January 28, 2012 http://www.weatherbell.com/saturday-summary--january-28-2012 JB just posted this link on his twitter site. I should emphasize that this is not a link to his paid site. I'm guessing he posted this as an advert for his site. In the video, he lays out his thoughts. Link to comment Share on other sites More sharing options...
michsnowfreak Posted January 29, 2012 Share Posted January 29, 2012 http://www.weatherbe...january-28-2012 JB just posted this link on his twitter site. I should emphasize that this is not a link to his paid site. I'm guessing he posted this as an advert for his site. In the video, he lays out his thoughts. For as much of a hypster as he is, he actually laid out some thoughts/reasonings that made sense why we may be seeing a "fab Feb" lol. Link to comment Share on other sites More sharing options...
Nic Posted January 29, 2012 Share Posted January 29, 2012 For as much of a hypster as he is, he actually laid out some thoughts/reasonings that made sense why we may be seeing a "fab Feb" lol. He had a reasonable explanation, which will make him look better if he busts. Link to comment Share on other sites More sharing options...
Ottawa Blizzard Posted January 29, 2012 Share Posted January 29, 2012 For as much of a hypster as he is, he actually laid out some thoughts/reasonings that made sense why we may be seeing a "fab Feb" lol. I would so laugh if JB gets this right and DT busts Link to comment Share on other sites More sharing options...
Ottawa Blizzard Posted January 29, 2012 Share Posted January 29, 2012 Here is DTs version of what should happen. He says it looks a lot like January 2002. http://www.wxrisk.com/ Link to comment Share on other sites More sharing options...
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