Ellinwood Posted August 12, 2011 Share Posted August 12, 2011 Winter 2011-2012: The monthly breakdown: METHODOLOGY: Used rough ENSO analogs (neutral ENSO to weak Nina summer going into weak/moderate Nina), coupled with NAO analogs based on correlation to -NAO summers (-NAO summer can imply a -NAO winter) (EDIT: I thought this correlation had more merit when catching the discussion on it... have since discounted this "reasoning" and went with the low Sun activity explanation) along with a -PDO and weighted accordingly. Not all analogs fit the NAO/PDO correlations, but still fit most of the requirements. They aren't perfect, but then again what is. ANALOGS: in [year (weight)] format 1995 (more) 2008 (more) 1970 (normal) 2000 (normal) 1962 (less) 2010 (less) Edited to add the PDO discussion because I forgot to write it in initially. NOTE: Anomalies are against 1971-2000 normals. Link to comment Share on other sites More sharing options...
BethesdaWX Posted August 12, 2011 Share Posted August 12, 2011 Well you pwned everyone on the outlook for summer 2011 One question, is there a reason you didn't at least slightly weight analogs before 1950? ENSO record doesn't go back all that far in specifics/certainty, but some years such as 1917-18 not only fit the 2010-11 La Nina for nationwide chill (1916-17), but also the Low Sun Aspect as well. AA-index values were very similar as well it seems. And if so, would years such as 1974-75 make sense? Link to comment Share on other sites More sharing options...
Ellinwood Posted August 12, 2011 Author Share Posted August 12, 2011 Well you pwned everyone on the outlook for summer 2011 One question, is there a reason you didn't at least slightly weight analogs before 1950? ENSO record doesn't go back all that far in specifics/certainty, but some years such as 1917-18 not only fit the 2010-11 La Nina for nationwide chill (1916-17), but also the Low Sun Aspect as well. AA-index values were very similar as well it seems. And if so, would years such as 1974-75 make sense? RE: Pre-1950 analogs: I didn't feel like digging up pre-1950 data RE: 1974... I'm discounting it for the same reason I discounted it in the summer: It wasn't anywhere close to the temperature pattern I was expecting and had seen from the other analogs I used. Link to comment Share on other sites More sharing options...
SoCoWx Posted August 13, 2011 Share Posted August 13, 2011 I agree and this is similar to my prelim. thoughts. Good luck! Link to comment Share on other sites More sharing options...
Ellinwood Posted August 15, 2011 Author Share Posted August 15, 2011 Bump to add the precip forecast: Not a snowfall forecast... The forecast and the verification for last winter can be found on my blog: http://t.co/RnAhvpj Link to comment Share on other sites More sharing options...
Roy Posted August 16, 2011 Share Posted August 16, 2011 I am in the very dry. Unfortunately, that forecast makes sense with the analogs and likely return of La Nina. Link to comment Share on other sites More sharing options...
Riptide Posted August 16, 2011 Share Posted August 16, 2011 Ugh, the la nada dryness returns. At least it won't be warm and dry.... I will hold your forecast with high regard, you are my favorite met. Link to comment Share on other sites More sharing options...
SoCoWx Posted August 16, 2011 Share Posted August 16, 2011 Seems very reasonable. I agree. And remember folks, just because precipiation is below normal doesnt mean snowfall cant be above normal. Link to comment Share on other sites More sharing options...
Ellinwood Posted October 20, 2011 Author Share Posted October 20, 2011 Here's the updated forecast for this winter. I used the same six analog years, with different weights (more below). IMPORTANT: The updated outlooks use the NEW 30-year normals (1981-2010), whereas the original forecast used the OLD normals (1971-2000). Overall, there were no drastic changes to the forecast. Winter 2011-2012: The monthly breakdown: ANALOGS: in [year (weight)] format 2010-11 (more) 1995-96 (more) 2008-09 (normal) 2000-01 (normal) 1970-71 (less) 1962-63 (less) So what changed? Overall there was slight warming in northern California, cooler Gulf Coast and a warmer northern New England. Most, if not all, of the changes can be attributed to subtle strengthening in the blocking pattern (more negative AO/NAO) that will allow the cold to work further into the south-central and southeastern U.S. At the same time, this blocking pattern will pull slightly warmer air in off of the Atlantic into northern New England. The ridging in the western U.S. has shifted slightly further west, which is why northern California turned warmer. It is also the other contributing factor that caused Texas to turn cooler. Warm risks are in place in Texas and the Southeast as ridging could be more prevalent in these areas. Precip/snowfall forecasts that I made previously are fairly similar to the update, so there isn't any need to go into detail about these. There is a wet risk in the Northeast, which I decided to leave as near normal while the region is borderline normal to above normal (especially in southern New England). From the analogs, 2010-11 was given more weight (equal to the weight of 1995), while 2008-09 and 1970-71 were given slightly less weight. I was going back and forth on whether or not to add 1955-56, but I decided that the La Niña in 1955-56 was too strong from the start of the summer through most of the winter compared to what is forecast (which will likely be a borderline weak/moderate La Niña). Link to comment Share on other sites More sharing options...
SoCoWx Posted October 20, 2011 Share Posted October 20, 2011 Out of shear bias, I really hope that December forecast verifies. I love a cold holiday season. Nice update! Link to comment Share on other sites More sharing options...
uncle W Posted October 20, 2011 Share Posted October 20, 2011 2010-11 (more) 1995-96 (more) 2008-09 (normal) 2000-01 (normal) 1970-71 (less) 1962-63 (less) good luck...I like your analogs but I'm bias cold......They are either cold or snowy or both...You have 1996 with the blizzard and Dec 62 with a 16" snowstorm in DC...Your top two analogs were blockbuster winters up here...I want a third straight great winter for NYC...At my age there might not be to many more to witness... Link to comment Share on other sites More sharing options...
Lee Posted October 21, 2011 Share Posted October 21, 2011 Ellinwood, your outlook looks very much like Foothills over on the SE board in case some hasn't saw it. His top analogue is last winter. Link to comment Share on other sites More sharing options...
WinterWxLuvr Posted October 21, 2011 Share Posted October 21, 2011 Interesting to note that CPC has now shifted their precip anomaly (wet) firmly into the OH and TN valley spreading east to (and a little east of) the Apps. The temp anomaly (cold) now covers a good portion of the northern tier. This is quite different from just a few months ago. I guess that is to be expected given that we are getting closer. I've seen 95-96 thrown around enough to get a little excited about it. I still think that was the best winter of my lifetime, even better than the 09-10 winter in the MA. Link to comment Share on other sites More sharing options...
tacoman25 Posted October 21, 2011 Share Posted October 21, 2011 Not a critique of this forecast, but I can think of very few times that using the previous winter as the top analog would have worked out well. However, I can definitely see how a lot of things this year do match up fairly well to last winter - foremost being the solar aspect. Link to comment Share on other sites More sharing options...
Ellinwood Posted October 21, 2011 Author Share Posted October 21, 2011 good luck...I like your analogs but I'm bias cold......They are either cold or snowy or both...You have 1996 with the blizzard and Dec 62 with a 16" snowstorm in DC...Your top two analogs were blockbuster winters up here...I want a third straight great winter for NYC...At my age there might not be to many more to witness... I do believe another 50" season is in store for NYC given the slightly above normal precip and colder temps (not to mention using last winter as a solid analog). Ellinwood, your outlook looks very much like Foothills over on the SE board in case some hasn't saw it. His top analogue is last winter. I did notice his forecast... glad to see some others holding onto a cold Southeast, whereas more people are siding to the neutral/above regime under some ridging. I am under the impression that, given weaker blocking overall compared to last year, the winter storms that rocked the Southeast last year will track a little further north this winter (possibly NC and southern VA to cash in more). Interesting to note that CPC has now shifted their precip anomaly (wet) firmly into the OH and TN valley spreading east to (and a little east of) the Apps. The temp anomaly (cold) now covers a good portion of the northern tier. This is quite different from just a few months ago. I guess that is to be expected given that we are getting closer. I've seen 95-96 thrown around enough to get a little excited about it. I still think that was the best winter of my lifetime, even better than the 09-10 winter in the MA. Most people are calling for a wetter OH/TN valley just west of the Apps, but I'm not convinced. I see longer spells of the cold/dry balancing out the periods of heavier precip, leading to a near normal year overall. While I'm a bigger proponent of 95-96 compared to most, one has to remember that 4 of my 6 analog years had below normal snowfall (at least at DCA). Not a critique of this forecast, but I can think of very few times that using the previous winter as the top analog would have worked out well. However, I can definitely see how a lot of things this year do match up fairly well to last winter - foremost being the solar aspect. Normally you wouldn't think so, but look at what happened during the summer... summer 2010 was the best analog for summer 2011! Given that most of the core values are setting up to be within an acceptable range of last year's numbers, there really isn't much reason to not use last winter. Sometimes it just works (if not always for the right reasons ) Link to comment Share on other sites More sharing options...
BethesdaWX Posted October 21, 2011 Share Posted October 21, 2011 Normally you wouldn't think so, but look at what happened during the summer... summer 2010 was the best analog for summer 2011! Given that most of the core values are setting up to be within an acceptable range of last year's numbers, there really isn't much reason to not use last winter. Sometimes it just works (if not always for the right reasons ) Summer 2011 really surprised me. But even more surprising is you nailed it months in advance flying in the face of past history, thats just scary man. If you nail this one be prepared for plenty of weenie imby PMs Link to comment Share on other sites More sharing options...
Midlo Snow Maker Posted October 21, 2011 Share Posted October 21, 2011 looks nice and cold just the way i like it good luck. i think you have alot mets in your camp. Link to comment Share on other sites More sharing options...
brad1551 Posted October 22, 2011 Share Posted October 22, 2011 Bravo, Bravo on the winter 2011-2012 forecast. I def concur on your forecast. The analouges match very well for this year. I have been looking a lots of info and I see an early snow in December this year. Good job again on your winter forecast. Link to comment Share on other sites More sharing options...
Ellinwood Posted March 4, 2012 Author Share Posted March 4, 2012 Verification time! So much fail... Monthly Temperature Grades: Dec: F Jan: F Feb: D- DJF Grades: Temp: F Precip: D Side-by-side comparisons on my blog: http://madusweather.com/2012/03/winter-2011-2012-forecast-verification/ Link to comment Share on other sites More sharing options...
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