bluewave

The late November weeklies in 2015 completely missed the record warmth for December. They had a stock Nino ridge in NW Canada and SE Nino trough for December. Instead we got the opposite with a PAC NW trough and SE ridge. My guess is that the error was missing the record MJO 5 El Niño pattern which produced the historic +13 warmth with that ridiculous standing wave. https://fox12weather.wordpress.com/2015/11/

Also a very Niña-like Northern branch of the jet stream with the December 2010 La Niña flooding record getting challenged in parts of Washington State. Plus the wettest first week of December on record ahead of La Niña years 2007 and 1975. Time Series Summary for Olympia Area, WA (ThreadEx) Click column heading to sort ascending, click again to sort descending. Rank Ending Date Total Precipitation Dec 1 to Dec 7 Missing Count 1 2023-12-07 6.73 2 2 2007-12-07 6.13 0 3 1975-12-07 5.91 0

We’ll we have been getting those regularly since the start of the month. In the old days, we didn’t regularly get 40°+ Decembers as frequently as we have since 2011. I bolded the 40°+Decembers since 2011. Time Series Summary for NY CITY CENTRAL PARK, NY - Month of Dec Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 2015 50.8 0 2 2001 44.1 0 3 2021 43.8 0 4 1984 43.7 0 5 2006 43.6 0 6 2011 43.3 0 7 1998 43.1 0 8 1982 42.7 0 9 1990 42.6 0 10 1891 42.5 0 11 1994 42.2 0 12 1923 42.0 0 13 2012 41.5 0 14 1996 41.3 0 - 1953 41.3 0 15 1979 41.1 0 16 1956 40.9 0 - 1931 40.9 0 17 1971 40.8 0 18 2014 40.5 0 - 1965 40.5 0 19 1957 40.2 0 20 2018 40.1 0

What do you consider a torch? To me any December over 40° in NYC is warm.

The models don’t have any real cold. It’s an average of normal days like today and near +10 days in the 50s to perhaps around 60° like we saw last weekend. So when you average out normal and +10 it’s still warm.

Just remember, there isn’t any difference in the warming potential to the pattern from a strong +1.9 El Niño and a super +2.1 El Niño. The important thing is how it combines with other signals like the MJO. The Maritime Continent phases will be active like we are seeing this month with an extensive +30C warm pool in the region which hasn’t happened before in an El Niño. The area around the Philippines near MJO 4-5 just had their warmest November on record. Plus there has been a rebound in SSTs north of Australia which is more Niña-like also. So these competing influences near the Dateline to the Maritime Continent amplify and slow the MJO in the warm MJO 4-7 phases. December starting with a very amplified forcing signal in MJO 4 and 7 which is very warm in North America

Yeah, what was left of the snowpack in the Long Beach West End turned into icebergs like in this video from the 950 mb benchmark blizzard in Mass when the storm surge came in. They froze into concrete blocks with the flash freeze the next morning.

We know that we can get Great Lakes cutters in El Niños as well as La Ninas. But some of the solutions showing up look as strong if not stronger than any December La Niña cutter of the last 3 years. It will be interesting to see if some of the stronger solutions verify.

The be all end all is getting the pattern right and finding the appropriate tools to get it done.

Yeah, a continuation of the fall pattern of the only cold in the Northern Hemisphere lining up on the other side of the globe.

Last December was the warmest La Niña on record around NYC with a -2.000 or lower monthly AO reading. If we can hold onto a -AO for the December average, then this could be the first El Niño -AO for NYC with a monthly average temperature over 40.0°. La Niña Decembers with -AO lower than -2.000 and NYC average temperature 2022….-2.719…38.5° 2010…..-2.631….32.8° 2005….-2.104…..35.3° 2000….-2.354….31.1° 1995…..-2.127….32.4° All El Niño -AO Decembers and NYC average temperature 2009….-3.413….35.9° 2002….-1.592….36.0° 1997…..-0.071…..38.2° 1987…..-0.534…..39.5° 1977…..-0.240…..35.6° 1976…..-2.074…..29.9° 1969…..-1.865…..33.4° 1968…..-0.783….34.2° 1963…..-1.178…..31.2° 1958……-1.687…..29.3°

This will be two Decembers in a row with a disappointing -AO pattern under both La Niña and El Niño patterns due to the very hostile Pacific.

But that isn’t what I said. MJO 8 is still warm during an El Niño but we see improvement with phases 2 and 3 in January. As for the weak SPV this month during the El Niño, all the cold is currently over in Eurasia. So it isn’t doing us any good. Hopefully, we see changes on that front during the winters 2nd half should blocking persist.

The one event I remember from that warm winter was the surprise high wind warming right before New Years. A neighbor had thrown out old paneling near the side of the curb. All of it blew away into peoples yards. The only memorable winters in the entire decade were 93-94 and 95-96. March 93 turned into a disappointment when the heavy snow quickly turned to heavy rain and we got a flash freeze the next morning. Had the March 93 superstorm taken a BM track, we could have easily seen widespread 20-30” wit some locally higher amounts possible.

The last time we did 8-1-3 during an El Niño was in January 2016. While phase 8 was still warm early on, we did see big improvements when it got into 1-2-3 with the historic blizzard when the signal finally weakened after 3. I think the record east based warmth in January 1998 held the convection too long in 8 and didn’t allow a colder progression to 1-2-3.

Phase 8 is warm in December into January during and El Niño. The most extreme example of this was January 1998.

You can go back in time in this thread and others and find lengthy papers and studies refuting all the points you brought up. So it’s not my job to to the homework for you.

None of the points that you made had anything to do with my original post.

Maritime Continent to Central Pacific MJO phases with a borderline super El Niño is a very warm signal for the CONUS. So it’s not a surprise that the models are correcting warmer. This pattern has supercharged the Pacific Jet which is flooding North America with mild Pacific air.

One of the main issues with the longer range model forecasts for the MJO beyond 10 days is that the ensembles weaken the convective signal too much. This is also true with the RMM charts. So some of the posts on twitter stating that the MJO will quickly weaken or progress to 8-1-2 are basing that on an an inherent model bias. So it’s no surprise that the convection in the warmer 4-7 phases this week is verifying more intense in the warm phases than the runs back in late November were indicating. This is one of the reasons ensemble forecasts have been correcting warmer for December than they were indicating later in November. So even if the MJO can eventually get over into phase 8 that is also a warmer signal from December into January. New run Old run

One of the main issues with the longer range model forecasts for the MJO beyond 10 days is that the ensembles weaken the convective signal too much. This is also true with the RMM charts. So some of the posts on twitter stating that the MJO will quickly weaken or progress to 8-1-2 are basing that on an an inherent model bias. So it’s no surprise that the convection in the warm phases this week is verifying more intense in the warm phases than the runs back in late November were indicating. This is one of the reasons ensemble forecasts have been correcting warmer for December than they were indicating later in November. So even if the MJO can eventually get over into phase 8, that is also a warmer signal from December into January with an El Niño. New run Old run

I think January 1998 was a case of the super El Niño combined with MJO 8 which is a warm pattern for us. That’s why all the talk of the MJO getting to phase 8 and cooling things off isn’t what we would expect during an El Niño. Pretty good match MJO 8 and El Nino

The MJO has successfully been used as a forecast tool for a while now. But the rapid expansion of the WPAC pool has slowed and amplified it in the warmer phases in recent times. Numerous papers were published in the last 5 years on this topic. So you are hearing about it now more because of the warming influence for us plus more understanding how it’s altering our local climate. Everything from mountain torques to sudden stratospheric warming have there roots in the MJO dynamics. So it’s right up there in importance with El Niño and La Niña. The key is figuring out how the ENSO and MJO will interact and drive the Rossby wave pattern.

The 91-20 baseline is now so warm that a modest +1.7 is still a top 10 warmest temperature. Time Series Summary for ISLIP-LI MACARTHUR AP, NY - Month of Sep Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Departure 1 2015 70.9 0 2 2005 70.2 0 3 2018 69.8 0 4 2021 69.6 0 - 1980 69.6 0 5 2017 69.0 0 - 2011 69.0 0 6 2016 68.9 0 7 2023 68.6 +1.7 - 1998 68.6 0 8 2010 68.3 0 9 2022 68.2 0 10 1983 68.1 0 - 1971 68.1 0

Plus people have to realize that MJO 8 isn’t necessarily cold in December during an El Niño. And that is if we even make it that far. One of the model biases for the ensembles week 2 is to dampen the tropical convection. Sometimes individual OP or ensemble runs can be more informative than a smoothed out lo res mean. So when people look to the end of the run and see the convection weakening it’s often the signal getting washed out in the long range model noise. And not the convection in the warm phases weakening. Then we have the well documented lag with MJO where we are still get a previous phase conditions for up to week following passage. So this is one of the reasons the warm phases tend to outlast what people expect.