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The month of December is almost upon us so we figured it was time to create a December winter thread. Looks like it could be a cold month with possible time frames that may support good conditions for winter storms. Let the breakdown begin! BTW Go VOLS today, #beatmizzou
Chicago WX posted a topic in Weather Forecasting and DiscussionSeason snowfall totals and the DJFM mean NAO and AO/NAM states for 16 Midwest and Northeast cities. I used the DJFM NAO and AO/NAM states as defined by Dr. James Hurrell: https://climatedataguide.ucar.edu/climate-data/hurrell-north-atlantic-oscillation-nao-index-station-based https://climatedataguide.ucar.edu/climate-data/hurrell-wintertime-slp-based-northern-annular-mode-nam-index First up, the overall statistics sorted by DJFM NAO values. I used median season snowfall totals for each city (1899-00 to 2013-14), to see if a season was "above normal" (AN), "below normal" (BN), or "around normal" (NM). HI in the chart is highest season total in each category, LO is the lowest, and AVG would be the average snowfall. Thing to keep in mind in all of this, is that these are all statistically based values/results. What the actual hemispheric charts look like may vary from certain NAO and AO/NAM values...and thus differing outcomes in some seasons. So despite all of this...buyer beware. Still, I think it's kind of interesting to see it broke down statistically. Columbus and Des Moines do better overall, in -NAO DJFM regimes. Green Bay is pretty much a toss up...and then you have Detroit, which does better overall in +NAO seasons. Matter of fact, it looks they are the opposite of every Midwest city in most categories. Indianapolis and St. Louis have better seasons with a -NAO...but I was a little surprised how badly STL did in strong -NAO's (-3 or lower). Chicago and Minneapolis are a little more mixed. Boston, Buffalo, and Burlington all seem to like a -NAO. Washington DC does too, as long as it's -2 or lower where 75% of the seasons are above the longterm median. A weak +NAO also sees DCA do well. All four have better season snowfall totals, overall, in -NAO winters...PIT especially so. PWM isn't as "dependent"...but still does better in -NAO seasons, -1 or lower particularly. Individual season charts up next.