jrodd321 Posted November 13, 2013 Share Posted November 13, 2013 Don it's nice to see you posting in here along with the other met's. Thanks. Thanks Andy. I agree with Andy. Can't wait for your analysis during upcoming storms this winter, Don. Link to comment Share on other sites More sharing options...
donsutherland1 Posted November 13, 2013 Share Posted November 13, 2013 For those who are interested, the following are some statistics related to the AO, ENSO and Philadelphia's seasonal snowfall. Apparently, one of my snowfall amounts referenced in #320 was incorrect. I regret the error. This data incorporates the correct seasonal snowfall amount. Link to comment Share on other sites More sharing options...
Rainshadow Posted November 13, 2013 Author Share Posted November 13, 2013 For those who are interested, the following are some statistics related to the AO, ENSO and Philadelphia's seasonal snowfall. Apparently, one of my snowfall amounts referenced in #320 was incorrect. I regret the error. This data incorporates the correct seasonal snowfall amount. Don, Great info as always. I can tell you since 1950 the NAO has been negative or was negative in the days leading up to 6 inch or great events in PHL 64% of the time and 71% of the time for single events greater than or equal 10 inches. Link to comment Share on other sites More sharing options...
GD0815 Posted November 13, 2013 Share Posted November 13, 2013 For those who are interested, the following are some statistics related to the AO, ENSO and Philadelphia's seasonal snowfall. Apparently, one of my snowfall amounts referenced in #320 was incorrect. I regret the error. This data incorporates the correct seasonal snowfall amount. Don, do you have some stats on how often the NAO and AO are in the same state--in other words, what percentage of time is there a -AO with a -NAO? Link to comment Share on other sites More sharing options...
donsutherland1 Posted November 14, 2013 Share Posted November 14, 2013 Don, do you have some stats on how often the NAO and AO are in the same state--in other words, what percentage of time is there a -AO with a -NAO? Yes. Here's the chart for AO+ (I'll make a chart to include the AO- data and post it a little later this evening): Link to comment Share on other sites More sharing options...
donsutherland1 Posted November 14, 2013 Share Posted November 14, 2013 Here's the AO-NAO chart when the AO is negative: Link to comment Share on other sites More sharing options...
Rainshadow Posted November 17, 2013 Author Share Posted November 17, 2013 I did some quick math and barring the early of next week not being somewhat torchy and/or the last week not being cold, looks like this November should end in the "normal third". It seems of late we have not had many enso neutral years as many of the analogs are quite old and kind of bland in the snowfall department. Link to comment Share on other sites More sharing options...
mupawxnut Posted November 17, 2013 Share Posted November 17, 2013 Any idea when this dry pattern may end? Link to comment Share on other sites More sharing options...
Rainshadow Posted November 22, 2013 Author Share Posted November 22, 2013 Any idea when this dry pattern may end? No. Precip outlooks have lower skill scores than temps. Link to comment Share on other sites More sharing options...
Rainshadow Posted November 22, 2013 Author Share Posted November 22, 2013 November is going to make a run for a bottom third. Given that 2012-13 is in that warm/cold list and this December has no low 40s look to it, this analog list is going to be ancient, not too many warm Octobers have been followed by chilly Novembers. Link to comment Share on other sites More sharing options...
chubbs Posted November 22, 2013 Share Posted November 22, 2013 November is going to make a run for a bottom third. Given that 2012-13 is in that warm/cold list and this December has no low 40s look to it, this analog list is going to be ancient, not too many warm Octobers have been followed by chilly Novembers. A difficult year to pattern. Does a cool August/September/November mean anything? Link to comment Share on other sites More sharing options...
Rainshadow Posted November 22, 2013 Author Share Posted November 22, 2013 A difficult year to pattern. Does a cool August/September/November mean anything? I looked at September when I first did this study for NYC winters in the 80s and there was some lean in the same direction as its departure for the following winter, but not on the same level of either October and November. I never looked at August. BTW the best ranked correlators for the ensuing winters in term of chi square testing (they all are in the same temp departure category) in that study were 1) warm October, 2) cold November and 3) cold October. So basically this fall like last fall guarantees no matter the outcome, one of these months (if not both if the winter is "normal") will fail. Link to comment Share on other sites More sharing options...
Rainshadow Posted November 25, 2013 Author Share Posted November 25, 2013 Final answer: ITS OUR ANNUAL LOOK TO SEE IF THE PAST CAN HAVE SOME CLUES AS TO HOW THIS UPCOMING WINTER WILL BE. GIVEN THE RARE COMBO AGAIN OF A WARM (TOP THIRD) OCTOBER AND A COLDER THAN THE LONG TERM MEDIAN NOVEMBER, WE HAD TO ASK SOME ARCHAEOLOGISTS FOR ASSISTANCE. WHILE LAST AUTUMN WE HAD A SIMILAR COMBINATION, THE NON-TROPICAL PACIFIC OCEAN IS IN A WHOLE DIFFERENT LEAGUE AND FOR BETTER OR WORSE 2012-13 DID NOT MAKE THE CUT. IN TERMS OF ENSO, THE LATEST CONSENSUS OF ALL DYNAMICAL MODELS FOR A DECEMBER, JANUARY AND FEBRUARY AVERAGE IS A MR. BLUTARSKY 0.0C. THE OUTLOOK CONSENSUS LEADING INTO THE SUMMER OF 2014 IS FOR AN EL NINO TO START DEVELOPING. THERE ARE ALREADY WARMER RELATIVE TO NORMAL WATERS ALONG THE EQUATORIAL PACIFIC WEST OF THE ENSO 3.4 REGION. FOR THIS REASON, THE ANALOGS CHOSEN VARIED FROM ENSO NEUTRAL NEGATIVE TO A WEAK EL NINO. BECAUSE OF THE DIRECTIONALITY, WE ONLY INCLUDED ONE WEAK LA NINA BECAUSE ITS DEPARTURES SINCE AUGUST WERE SIMILAR TO THIS YEAR. CLIMATOLOGICALLY SPEAKING SINCE THE WINTER OF 1949-50, THERE HAS BEEN AN INTERESTING CLIMATOLOGICAL SPLIT WITH ENSO NEUTRAL WINTERS IN PHILADELPHIA. ENSO NEUTRAL POSITIVE WINTERS HAVE LACKED LARGER SNOW EVENTS. THERE HAS BEEN ONLY TWO SIX INCH OR GREATER EVENTS (OUT OF SIX ENSO NEUTRAL POSITIVE WINTERS) SINCE 1950. COMPARE THIS TO A WEAK EL NINO THAT HAS HAD EIGHT (OUT OF TEN WINTERS) AND ENSO NEUTRAL NEGATIVE THAT HAS HAD THIRTEEN (OUT OF FOURTEEN WINTERS). OF LATE SNOW STORMS THAT HAVE AFFECTED OUR AREA HAVE BEEN MORE WHOPPERS THAN RUN-OF-THE-MILL ONES. OF THE TWENTY-ONE TEN INCH OR GREATER EVENTS IN PHILADELPHIA SINCE 1950, TWELVE OF THEM HAVE OCCURRED SINCE THE WINTER OF 1995-96 AND FIVE OF THE LAST SIX SNOWFALL EVENTS THAT HAVE CROSSED THE SIX INCH THRESHOLD WERE TEN INCHES OR MORE. LAST WINTER THE OUTLOOK TREND WAS TOWARD EL NINO, BUT THE EASTERN NON-TROPICAL PACIFIC WAS MORE HOSTILE. TAKING US TO THE REST OF THE PACIFIC. WARMER THAN NORMAL SEA SURFACE TEMPERATURE DEPARTURES HAVE MADE IT INTO THE EASTERN PACIFIC. THE PACIFIC DECADAL OSCILLATION WHICH WAS STRONGLY NEGATIVE LAST FALL AND WINTER (WHEN THE WARMEST WATERS WERE CONFINED WEST), IS CLOSER TO NEUTRAL HEADING INTO THIS WINTER. WE HAVE ALREADY SEEN THE EFFECTS OF THIS IN NOVEMBER AS THE EASTERN PACIFIC OSCILLATION TELECONNECTION INDEX HAS BEEN NEGATIVE (MORE EASTERN PACIFIC RIDGING) AND HAS SET IN MOTION A STRING OF VERY STRONG HIGH PRESSURE SYSTEMS FROM CANADA INTO THE UNITED STATES. AS FOR TRYING TO OUTLOOK THE NORTH ATLANTIC OSCILLATION WE HAVE LOOKED AT APPROXIMATELY SEVEN DIFFERENT METHODS THAT HAVE HAD SOME DEGREE OF SUCCESS IN THE PAST. THE SCOREBOARD FOR THIS WINTER IS THREE FOR NAO POSITIVE, AND FOUR FOR NAO NEGATIVE. THE MORE POPULAR ONE (DEFACTO NAO BECAUSE IT IS AN AO OUTLOOK. THE FORMER NORMALLY FOLLOWS ABOUT 75 PERCENT OF THE TIME) OF LATE HAS BEEN THE ADVANCE OF SNOW COVERAGE IN SIBERIA IN OCTOBER. FROM THE RUTGERS WEB SITE, WE SAW THAT SNOW COVERAGE ADVANCED QUICKLY IN SEPTEMBER AND THE FIRST HALF OF OCTOBER, BUT THEN SLOWED IN THE SECOND HALF OF OCTOBER. IN SPITE OF THIS, EURASIAN SNOW COVERAGE FOR THE MONTH OF OCTOBER WAS THE GREATEST SINCE 2002. LOCALLY WE HAVE FOUND ITS A BETTER INDICATOR OF SNOW THAN TEMPERATURES. SEASONAL SNOWFALL STATISTICALLY SPEAKING IS NOT A NORMAL DISTRIBUTION, BUT A GAMMA DISTRIBUTION. THE SNOWY WINTERS SKEW THE AVERAGE HIGHER. THE MOST LIKELY OUTCOME FOR ANY GIVEN WINTER IS BELOW AVERAGE SNOWFALL. PHILADELPHIA`S MEDIAN SNOW SINCE 1967 HAS BEEN 17.75". SINCE SNOW COVERAGE HAS BEEN MAPPED BY SATELLITE, 33 PERCENT OF ALL WINTERS HAVE HAD SNOWFALL ABOVE THE CURRENT NORMAL. BUT WHEN EURASIAN SNOW COVER IS GREATER THAN NORMAL IN OCTOBER, THE PAST PERCENTAGE HAS INCREASED TO ABOUT 50 PERCENT. THIS DID NOT HELP US LAST WINTER. OF COURSE IF THE EPO REMAINS STRONGLY NEGATIVE, THE NAO STATUS WILL NOT MATTER AS MUCH. THIS TAKES US TO OUR FALL TEMPERATURES. OF THE 46 WARMEST WINTERS IN PHILADELPHIA ON RECORD, HALF OF THEM HAVE OCCURRED AFTER A WARM OCTOBER. THIS NOVEMBER WILL END RIGHT AROUND THE CUSP BETWEEN THE UNSEASONABLY COLD AND NORMAL TERCILES. REGARDLESS THIS IS A RARER OCCURRENCE AND A CONTRADICTION IN THE STUDY FIRST DONE IN WHICH THE STRONGEST CORRELATOR FOR A WARM WINTER IS A WARM OCTOBER WHILE THE STRONGEST CORRELATOR FOR A COLD WINTER IS A COLD NOVEMBER. OUR COLLEAGUE FROM ACROSS THE AISLE USED TO USE OCTOBER MINS AND NOVEMBER MAXES (THAT EXPLAINED ABOUT 50% OF THE VARIANCE) FOR HIS WINTER OUTLOOK. IN HIS STUDY, THESE TWO MONTHS WOULD NEARLY CANCEL EACH OTHER OUT. SO THE YEARS IN THIS ANALOG MAY LOOK FAMILIAR, SOME WERE REPEATS FROM LAST WINTER`S OUTLOOK. OF THESE SEVEN, THREE WERE ENSO NEUTRAL NEGATIVE, TWO WERE ENSO NEUTRAL POSITIVE, ONE WAS A WEAK EL NINO AND ONE WAS A WEAK LA NINA. THERE WERE ABOUT 10 OTHER CANDIDATES, BUT WE REMOVED ANY THAT HAD UNSEASONABLY WARM OR COLD DECEMBERS. AT THIS JUNCTURE NEITHER EXTREME APPEARS LIKELY. SO HERE ARE OUR LUCKY SEVEN ANALOGS FOR THIS UPCOMING WINTER FOR PHILADELPHIA. THEIR MILEAGE MAY VARY: SEASON DEC JAN FEB WINTER SEASONAL WINTER AVG AVG AVG AVG SNOWFALL* PCPN 1882-3 36.2 30.6 37.0 34.6 N/A 11.14 1914-5 33.3 36.6 38.8 36.2 32.3 19.64 1924-5 36.2 31.8 42.2 36.7 12.1 8.52 1941-2 38.3 30.5 30.8 33.2 10.3 9.24 1951-2 38.7 37.3 38.2 38.1 16.2 7.58 1954-5 36.0 32.6 36.1 34.9 12.1 5.60 1959-0 38.2 34.2 35.4 35.9 21.8 10.17 AVG 36.7 33.4 36.9 35.7 17.5 10.27 1981-2010 NML 37.5 33.0 35.7 35.4 22.4 9.24 THE OFFICIAL CPC OUTLOOK FOR THE WINTER IS FOR EQUAL CHANCES OF IT BEING EITHER WARMER OR COLDER THAN NORMAL AND EITHER WETTER OR DRIER THAN NORMAL. WE WANT TO WISH EVERYONE A VERY HAPPY THANKSGIVING AND MAY THIS WINTER LIVE UP TO YOUR EXPECTATIONS. Link to comment Share on other sites More sharing options...
Rainshadow Posted November 25, 2013 Author Share Posted November 25, 2013 Our products still go out with all caps, I'm not shouting at anyone. Link to comment Share on other sites More sharing options...
famartin Posted November 25, 2013 Share Posted November 25, 2013 IN TERMS OF ENSO, THE LATEST CONSENSUS OF ALL DYNAMICAL MODELS FOR A DECEMBER, JANUARY AND FEBRUARY AVERAGE IS A MR. BLUTARSKY 0.0C. THE I'm pretty sure that's the first "Animal House" reference I've seen in an AFD Link to comment Share on other sites More sharing options...
Rainshadow Posted November 25, 2013 Author Share Posted November 25, 2013 I'm pretty sure that's the first "Animal House" reference I've seen in an AFD Shirley, you must be kidding. Link to comment Share on other sites More sharing options...
Absolute Humidity Posted November 26, 2013 Share Posted November 26, 2013 "DECEMBER, JANUARY AND FEBRUARY AVERAGE IS A MR. BLUTARSKY 0.0C." Almost sprayed the PC monitor with coffee when I read that! good stuff Link to comment Share on other sites More sharing options...
Isotherm Posted November 27, 2013 Share Posted November 27, 2013 Good stuff Tony. I had to look up that reference but once I saw the youtube video was laughing out loud. Link to comment Share on other sites More sharing options...
uncle W Posted November 27, 2013 Share Posted November 27, 2013 Our products still go out with all caps, I'm not shouting at anyone. nice read Tony...I came up with these analogs with a mild October and cold November...I'm using NYC temps...1947 and 1995 are on the list but so is 2007-08...I'll sign up for 1959-60 in a heart beat even though January and February was lacking in snow and cold.... 1920... 1947... 1955... 1959... 1971... 1995... 2007... Link to comment Share on other sites More sharing options...
Quakertown needs snow Posted November 27, 2013 Share Posted November 27, 2013 Our products still go out with all caps, I'm not shouting at anyone. I've been wondering this for a long time, thought it was a stress thing 0.0, nice touch Link to comment Share on other sites More sharing options...
Rainshadow Posted November 27, 2013 Author Share Posted November 27, 2013 nice read Tony...I came up with these analogs with a mild October and cold November...I'm using NYC temps...1947 and 1995 are on the list but so is 2007-08...I'll sign up for 1959-60 in a heart beat even though January and February was lacking in snow and cold.... 1920... 1947... 1955... 1959... 1971... 1995... 2007... Uncle, I had about 16 or 17 candidates and what my WAG December was going to look like (not extreme in either direction) I saw 1947 and 1995 on my radar too, but those Decembers looked too cold and I believe today's 63 or 64 solidifies "a normal" third November for PHL. On the other end same reason I chucked 1971 and 2012, their Decembers looked too warm. My research was solely based on temps, so the snow is kind of a tag along. Only enso states I feel confident about snow are the extremes and strong ninos only after December is done. Link to comment Share on other sites More sharing options...
Rainshadow Posted November 27, 2013 Author Share Posted November 27, 2013 By the way thank-you everyone for a very enjoyable outlook thread this fall! I hope you and your families have a very Happy Thanksgiving! Link to comment Share on other sites More sharing options...
snowlurker Posted November 28, 2013 Share Posted November 28, 2013 By the way thank-you everyone for a very enjoyable outlook thread this fall! I hope you and your families have a very Happy Thanksgiving! Happy Thanksgiving Tony! I enjoy your forecast discussions and you and your colleagues' winter outlooks. Link to comment Share on other sites More sharing options...
mcwx Posted November 28, 2013 Share Posted November 28, 2013 By the way thank-you everyone for a very enjoyable outlook thread this fall! I hope you and your families have a very Happy Thanksgiving! Happy Thanksgiving Tony. I always enjoy your commentary Link to comment Share on other sites More sharing options...
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