raindancewx Posted November 20, 2020 Share Posted November 20, 2020 December is favored to do what I expected in my outlook from October now that the earlier November idea of a late Nov -NAO seems to be off the table. Still think the NAO will go negative at some point in December, but I had December pretty warm anyway, and that still looks right to me. Link to comment Share on other sites More sharing options...
40/70 Benchmark Posted November 21, 2020 Share Posted November 21, 2020 2 minutes ago, 40/70 Benchmark said: ACE is up to 180....I think @raindancewx said 175 was the breaking point for snowier outcomes in the NE, but since they name every pop up shower today, maybe 170 is a more accurate assessment of this season's activity. Close. Link to comment Share on other sites More sharing options...
40/70 Benchmark Posted November 21, 2020 Share Posted November 21, 2020 2 minutes ago, WxWatcher007 said: 175-180 ACE is legit IMO. Maybe there were some early in the season that wouldn’t have been named back in the day but they were all short lived. This season produced. Yea, I was being conservative. 1 Link to comment Share on other sites More sharing options...
40/70 Benchmark Posted November 21, 2020 Share Posted November 21, 2020 19 minutes ago, WxWatcher007 said: What I do wonder is whether the backloaded nature of the season has an impact. The Greek letters really carried what would have been an unspectacular ACE season in late October and November. I don't see why it should...its hurricane season. Do we look at 2015 and 2005 any differently in terms of snowfall? 1 Link to comment Share on other sites More sharing options...
raindancewx Posted November 22, 2020 Share Posted November 22, 2020 I never said 175 or 180 is a breaking point for the NE. It's a breaking point for what I forecast. The years well above 180 are all very hot here, and start to become the best analogs. My unweighted blend actually had about 155 ACE, but since I like 2007 I gave it half weight. It's not just not 1995 in my blend that does it either, I had 2003 in there which is almost identical to the ACE this year. What I did say is the top snowfall in the NE in La Nina years tend to cluster above 150 ACE. NYC/Philly in particular have literally no good snowfall years in a La Nina below 150 ACE. But it's about a coin-flip above 150. 1933, 1995, 2005, 2010, 2017 are the good ones for you guys I think. 2010 is not awful here, but I don't like it as an analog, and the others are very hot/dry here. This pattern is definitely a lot wetter/different here than the non-2010 years though. We've also already had more snow than all of those years just in October where I am. 2 Link to comment Share on other sites More sharing options...
40/70 Benchmark Posted November 22, 2020 Share Posted November 22, 2020 17 minutes ago, raindancewx said: I never said 175 or 180 is a breaking point for the NE. It's a breaking point for what I forecast. The years well above 180 are all very hot here, and start to become the best analogs. My unweighted blend actually had about 155 ACE, but since I like 2007 I gave it half weight. It's not just not 1995 in my blend that does it either, I had 2003 in there which is almost identical to the ACE this year. What I did say is the top snowfall in the NE in La Nina years tend to cluster above 150 ACE. NYC/Philly in particular have literally no good snowfall years in a La Nina below 150 ACE. But it's about a coin-flip above 150. 1933, 1995, 2005, 2010, 2017 are the good ones for you guys I think. 2010 is not awful here, but I don't like it as an analog, and the others are very hot/dry here. This pattern is definitely a lot wetter/different here than the non-2010 years though. We've also already had more snow than all of those years just in October where I am. Thanks for the clarification. Link to comment Share on other sites More sharing options...
raindancewx Posted November 22, 2020 Share Posted November 22, 2020 For the La Ninas since 1930, I found something like 0/18 are 'snowy' for NYC/Philly <150 ACE, and 5/10 are snowy >=150 ACE. It's not as important for Boston, but still preferential for higher ACE. Snowy here meaning more than +20% compared to average. One warning with the La Nina ACE stuff - the correlations aren't just for the NE, they are for the SW too. The correlation here is already likely to be pretty wrong for snow - although it's much weaker than for temperatures overall. The real strong La Nina ACE correlation here is Dec 16-Jan 15 highs. Albuquerque averages ~six inches of snow in La Ninas. But we've already had 4.4" officially. So if you throw out the La Ninas with less than 4.4" snow, you end up with a La Nina average of 8.1", which is near the long-term average of 9.6". Locally, 100% of years with measurable snow (10/10) see at least five months of measurable snow Oct-May. In years without October snow, it's more like 30%. That's the main effect. Years without October snow, tend to see 2-4 months of snow. These are my guidelines locally at this point - but you can see none of them really gel with the ACE index idea now. Basically: October + La Nina average the rest of the way --> 10.6" snow (4.4" + 6.2" --> +10%) La Nina with at least four inches of snow average 8.1" snow (4.4" + 3.7" --> -15%) October + Average of "five month" snow years from Nov-May --> (4.4" + 8.2" --> 12.4" snow (+30%) I'd say the 10.6" is the most likely, but 1/3 of La Ninas will see <3.7" in Nov-May, and 1/3 will see >8.2" in Nov-May. So I think the outcomes above are useful scenarios. My guess is snow tendencies won't change too much the next six weeks from the established pattern. Just a southward shift as winter arrives. Similar look through mid-January though. 1 Link to comment Share on other sites More sharing options...
Damage In Tolland Posted November 22, 2020 Share Posted November 22, 2020 9 hours ago, donsutherland1 said: With sunshine that persisted into the afternoon, temperatures rose well into the 60s in much of the region. Tomorrow will be cooler under mainly cloudy skies. Showers are likely. A steadier rain could develop later in the day or at night. Most of the remaining days this month could see readings near or above normal with some short-lived cool shots possible. One such cool shot is likely early next week. December could see above to perhaps much above normal temperatures redevelop during the first week of the month. The ENSO Region 1+2 anomaly was -0.3°C and the Region 3.4 anomaly was -1.0°C for the week centered around November 11. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.98°C and the ENSO Region 3.4 anomaly has averaged -1.44°C. La Niña conditions will likely prevail at least through the winter. The SOI was +2.86. Today, the preliminary Arctic Oscillation (AO) figure was +3.262. On November 20 the MJO was in Phase 2 at an amplitude of 1.401 (RMM). The November 19-adjusted amplitude was 1.581. Based on the latest guidance, no significant stratospheric warming event is likely through at least November 25. The lack of such warming could favor the gradual strengthening of the stratospheric polar vortex. A strong polar vortex, which is favored on the long-range guidance, could have implications for the opening of meteorological winter. Since 1950, there have been five cases where a La Niña developed during June-July-August or afterward following an El Niño winter. 4/5 (80%) of those cases saw a predominant EPO+/AO+ winter pattern. The most recent such case was 2016-17. 10/11 (91%) of the La Niña winters that followed an El Niño winter featured a predominantly positive EPO. A predominant EPO+/AO+ pattern is very likely for winter 2020-21. It is likely that the Middle Atlantic and southern New England areas will see a warmer than normal winter with below normal snowfall. The November run of the seasonal European guidance suggests that winter 2020-21 will likely be warmer to much warmer than normal in the region. The potential also exists for below to much below normal seasonal snowfall in the Middle Atlantic and southern New England areas. Since 1970, there were 9 winters that saw the AO and EPO average +0.25 or above. Mean snowfall for Boston, Harrisburg, New York City, Philadelphia, and Washington, DC averaged 50% of the most recent 30-season mean. The largest snowfall deficits relative to the most recent 30-season mean figure were located in the Philadelphia to New York City corridor. In addition, 33% of cases saw less than 10" seasonal snowfall in New York City and 44% saw less than 10" seasonal snowfall in Philadelphia. Based on sensitivity analysis applied to the latest guidance, there is an implied 99% probability that New York City will have a warmer than normal November. November will likely finish with a mean temperature near 51.2°. The implied probability for a November mean temperature of 50.0° in Central Park is now approximately 81%. Since 1869, there have been 19 cases where November had a mean temperature of 50.0° or above. 14/19 (74%) went on to have a warmer than normal December, including 9/19 (47%) with a December mean temperature of 40.0° or above (2.5° or more above normal). The winter mean temperature for those 14 cases was 37.5° (2.2° above normal). The winter mean temperature for the subset of December cases with a mean temperature of 40.0° or above was 38.9° (3.6° above normal) and four of those cases wound up having an average winter temperature of 40.0° or above. Terrible news here 1 2 Link to comment Share on other sites More sharing options...
CoastalWx Posted November 22, 2020 Share Posted November 22, 2020 I’ll take 16-17 despite the pack never surviving. Two great storms and another one that was epic for deep interior. 1 1 Link to comment Share on other sites More sharing options...
Baroclinic Zone Posted November 22, 2020 Share Posted November 22, 2020 Saw Harv talking to Judah on news. Warmer then normal temps but calling for slightly above normal snow. Link to comment Share on other sites More sharing options...
Baroclinic Zone Posted November 22, 2020 Share Posted November 22, 2020 7 minutes ago, CoastalWx said: I’ll take 16-17 despite the pack never surviving. Two great storms and another one that was epic for deep interior. Couple footers + that season a month apart. Link to comment Share on other sites More sharing options...
ORH_wxman Posted November 22, 2020 Author Share Posted November 22, 2020 39 minutes ago, Baroclinic Zone said: Couple footers + that season a month apart. Yeah down there I think you had 1/7-8/17 and 2/9/17. Link to comment Share on other sites More sharing options...
Baroclinic Zone Posted November 22, 2020 Share Posted November 22, 2020 26 minutes ago, ORH_wxman said: Yeah down there I think you had 1/7-8/17 and 2/9/17. Yeah Link to comment Share on other sites More sharing options...
DavisStraight Posted November 22, 2020 Share Posted November 22, 2020 2 hours ago, Baroclinic Zone said: Saw Harv talking to Judah on news. Warmer then normal temps but calling for slightly above normal snow. I'll take that. Link to comment Share on other sites More sharing options...
40/70 Benchmark Posted November 22, 2020 Share Posted November 22, 2020 5 hours ago, Damage In Tolland said: Terrible news here Nothing new. 1 Link to comment Share on other sites More sharing options...
J Paul Gordon Posted November 23, 2020 Share Posted November 23, 2020 All it takes, though, is the right combo of cold air and precip to wind up a decent snowstorm in the interior even in lousy winters. January 2006 is a case in point of a significantly above average month (only 7 days with a high below freezing at ORH airport) with above average snow (24"). Link to comment Share on other sites More sharing options...
weathafella Posted November 23, 2020 Share Posted November 23, 2020 34 minutes ago, J Paul Gordon said: All it takes, though, is the right combo of cold air and precip to wind up a decent snowstorm in the interior even in lousy winters. January 2006 is a case in point of a significantly above average month (only 7 days with a high below freezing at ORH airport) with above average snow (24"). You probably mean February? Link to comment Share on other sites More sharing options...
Go Kart Mozart Posted November 23, 2020 Share Posted November 23, 2020 7 minutes ago, weathafella said: You probably mean February? Avatar change? Link to comment Share on other sites More sharing options...
weathafella Posted November 23, 2020 Share Posted November 23, 2020 2 hours ago, Go Kart Mozart said: Avatar change? Not since 2001 for me... 1 Link to comment Share on other sites More sharing options...
Go Kart Mozart Posted November 23, 2020 Share Posted November 23, 2020 That's weird. On my screen I am seeing a pic of a 40ish year old man with glasses, no more western-guy. Link to comment Share on other sites More sharing options...
mreaves Posted November 23, 2020 Share Posted November 23, 2020 16 minutes ago, Go Kart Mozart said: That's weird. On my screen I am seeing a pic of a 40ish year old man with glasses, no more western-guy. ? Link to comment Share on other sites More sharing options...
ORH_wxman Posted November 23, 2020 Author Share Posted November 23, 2020 12 hours ago, weathafella said: You probably mean February? Nope, Jan 2006 had over 2 feet at ORH...a couple solid warning events (Jan 2-3 and Jan 23) mixed with a couple smaller ones. Link to comment Share on other sites More sharing options...
Go Kart Mozart Posted November 23, 2020 Share Posted November 23, 2020 2 hours ago, mreaves said: ? OK, I am back to seeing the "western guy", at least on my work computer. That was weird. It looked like a pic of the judge from the old TV show Night Court. I will have to check my laptop when I get home. Link to comment Share on other sites More sharing options...
MJO812 Posted November 23, 2020 Share Posted November 23, 2020 People are already getting hyped on social media for the 1st half of December in the east. Eps looks really good for the 1st week of December with a big pna spike. 5 Link to comment Share on other sites More sharing options...
40/70 Benchmark Posted November 23, 2020 Share Posted November 23, 2020 1 minute ago, MJO812 said: People are already getting hyped on social media for the 1st half of December in the east. Eps looks really good for the 1st week of December with a big pna spike. There isn't any cold air for the PNA to tap, though....that may work during the heart of winter, but it won't in early December....at least not for I95. 1 Link to comment Share on other sites More sharing options...
J Paul Gordon Posted November 23, 2020 Share Posted November 23, 2020 Oh sure it can, at least where you are. We get monster slop/snow/ice storms in some scenarios under a regime like this even early in December. Maybe especially early in December. Ice storms especially. A transitory Quebec High can sometimes do wonders. Link to comment Share on other sites More sharing options...
40/70 Benchmark Posted November 23, 2020 Share Posted November 23, 2020 4 minutes ago, J Paul Gordon said: Oh sure it can, at least where you are. We get monster slop/snow/ice storms in some scenarios under a regime like this even early in December. Maybe especially early in December. Ice storms especially. A transitory Quebec High can sometimes do wonders. There needs to be a cold source......the high is the vehicle for the cold. Worcester hills could probably pull it off, sure. Link to comment Share on other sites More sharing options...
J Paul Gordon Posted November 23, 2020 Share Posted November 23, 2020 28 minutes ago, 40/70 Benchmark said: There needs to be a cold source......the high is the vehicle for the cold. Worcester hills could probably pull it off, sure. Tolland Massiff and NE/NW CT, NW RI, along 95-495 belt northeastward. Sometime interior SE MA can get a good icing in that kind situation in a generally BAH HUMBUG pattern. Have to count the little blessings in the midst of the larger storm. Link to comment Share on other sites More sharing options...
ORH_wxman Posted November 23, 2020 Author Share Posted November 23, 2020 We could pull something off in first week of December if it is well-timed but I'm definitely not expecting it. It would serve us well to wait for at least a little bit of EPO-easing. We don't need a nuclear ridge there, but we need enough to flush the putrid dreck out of Canada. 2 Link to comment Share on other sites More sharing options...
40/70 Benchmark Posted November 23, 2020 Share Posted November 23, 2020 SO MEI value held at -1.2 https://psl.noaa.gov/enso/mei/ Link to comment Share on other sites More sharing options...
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