bluewave

There is a difference between needing a jacket and whether the pattern is warm or cold for this time of year. Most days we’ll need a jacket even it’s +10 since it’s only March. The means do a good job at showing the warmth. As for frozen precip, very unlikely coastal sections see much next few weeks.

I removed the original post since you completely missed the points that I was trying to make. I will try to break it down piece by piece in this new post. While the geographic locations of the temperature anomalies this winter we’re correlated to the El Niño, the magnitude of departures could not simply be reduced to saying it was a result of the El Niño. Sections to the north and the CONUS had their warmest winter on record with departures in spots above +10 against the warmest 30 year climate normals over the 91-20 period. The intensity of this El Niño wasn’t nearly as strong as the past winters which were previous the warmest record holders. So there was much more than just the El Niño going on this winter. My reference to the difference in the 500 mb anomalies this winter from past El Niño instances goes to the issue of why the deeper trough which was modeled by the Euro seasonal didn’t occur in the South. First, we saw record warmth for the WPAC basin during an El Niño. This is what I was pointing out in this thread last fall. My concern was that the risks to the winter forecasts would be much warmer than the computer models from various centers were indicating. It’s also why one dimensional model forecasts based mostly on El Niño were biased so cold. The more westward forcing even at times back to the eastern IO combined with the El Niño to produce warmth well beyond any seasonal forecast this winter. So these marine heatwaves in the warm forcing areas for North America realized through unusually active MJO 4-7 action for an El Niño contributed to the much warmer departures than a one dimensional El Niño model would suggest. So the more westward forcing for an El Niño would tend to weaken this trough and cold potential in the south. This forcing combined with the El Niño through the El Niño set of MJO composites also created the stronger 500 mb and ridge and warmth to the north. A second reason I showed 500 mb charts was to illustrate how different a response we got from the Aleutian low this winter than has typically been the case with stronger El Niños.This was the weakest Aleutian low response we have seen from a stronger El Nino. My guess is this is related to the more westward forcing lean which actually produced a ridge south of the Aleutians and to the NW of Hawaii instead of the trough being forecast by the models. Now you can say this is related to the -PDO and to an extent this is the case. But the -PDO this winter was more defined by the warm waters near Japan and west of the Dateline rather than the usual cold ring In the east. So we have seen a shift in the way the PDO has be manifesting in recent years. Plus there have been recent studies that the PDO is more of an effect than a cause of the pattern across the North Pacific. This SST pattern may just be an effect of the predominant forcing at any given time. I would agree with you that the enhanced STJ was one of the more typical El Niño responses this winter which did work out. But the extreme flooding and record rainfall in places like California was stronger in spots than even the 97-98 El Niño which was much stronger could muster. So another example of the overlapping influences this winter.

No cold air.

No cold air in sight as the ensembles remain much warmer than average next few weeks.

Top 10 warmest start to March. Time Series Summary for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Rank Ending Date Mean Avg Temperature Mar 1 to Mar 3 Missing Count 1 1991-03-03 55.3 0 2 1972-03-03 54.3 0 3 2004-03-03 54.0 0 4 1882-03-03 49.8 0 5 1966-03-03 48.7 0 6 2024-03-03 48.5 0 7 1983-03-03 48.2 0 - 1921-03-03 48.2 0 8 2017-03-03 47.7 0 9 1902-03-03 47.5 0 10 1871-03-03 47.3 0

It would be interesting find out why the timing and magnitude of the warmth with this El Niño was so different from past events.

Very impressive warmth.

Warm and super amped up MJO facing off against the strong -AO due to the final or major SSW is a very rainy pattern in the early spring. So a raging Pacific Jet undercutting the -AO block. Another case in recent times of the Pacific overpowering the Atlantic.

The only real heat that summer was the memorable heatwave in mid-July. The summer average was cool compared to our warmer summers since 2010. Those 70s heatwaves lacked the staying power that we get regularly today. The NYC summer monthly departures for todays climate in 1977 were -1.8,+1.5, and -0.4. Monthly Mean Avg Temperature for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Year Jun Jul Aug Season Mean 73.4 80.1 77.4 77.0 2023 71.6 80.6 76.7 76.3 2022 74.4 82.6 80.5 79.2 2021 76.2 78.8 80.0 78.3 2020 74.4 80.8 77.7 77.6 2019 72.7 80.6 76.2 76.5 2018 72.1 78.2 79.2 76.5 2017 72.7 77.3 74.0 74.7 2016 72.9 79.9 79.9 77.6 2015 72.0 79.0 78.7 76.6 2014 72.8 77.0 74.5 74.8 2013 73.3 80.9 74.7 76.3 2012 72.4 80.8 77.6 76.9 2011 74.5 82.7 76.9 78.0 2010 76.2 82.3 77.7 78.7 Monthly Mean Avg Temperature for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Year Jun Jul Aug Season Mean 71.6 77.0 76.2 74.9 1979 69.3 77.0 76.6 74.3 1978 71.6 75.0 76.6 74.4 1977 70.3 78.1 75.1 74.5 1976 73.6 74.9 74.4 74.3 1975 71.6 76.9 75.0 74.5 1974 70.1 77.1 76.4 74.5 1973 74.6 78.6 79.6 77.6 1972 68.8 77.9 75.9 74.2 1971 74.8 77.7 76.0 76.2

The summer of 1977 was cool by todays standards. People remember the 10 day heatwave in mid-July. But the rest of the summer was cool.

Thanks for creating that chart. NYC would have more top 10 warmest months If they measured the temperatures the same way as before the 1990s. Switching to measurements under the fully leafed out trees during the warmer months since the 90s lowered the rankings of recent years. We can see how during the colder months when the leaves on the trees aren’t an issue, NYC has a similar amount of top 10 warmest months as the surrounding stations. But it has fallen behind during the summer when the deep shade artificially cools the readings since the 1990s. Plus NYC is also losing top 10s after the spring leaf out and before the fall leaf drop. NYC top 10 warmest summers dense ranked by temperature https://www.sqltutorial.org/sql-window-functions/sql-dense_rank/ Summers since 2010 bolded NYC 5 top 10 warmest temperature summers Time Series Summary for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 2010 77.8 0 2 1966 77.3 0 3 2005 77.1 0 4 2020 76.9 0 - 1993 76.9 0 - 1983 76.9 0 5 1949 76.8 0 6 2022 76.7 0 - 2016 76.7 0 - 1999 76.7 0 7 1988 76.6 0 - 1980 76.6 0 - 1906 76.6 0 8 1995 76.5 0 - 1944 76.5 0 9 2015 76.3 0 - 1991 76.3 0 - 1952 76.3 0 - 1943 76.3 0 - 1908 76.3 0 10 1994 76.2 0 LGA 8 top 10 Time Series Summary for LAGUARDIA AIRPORT, NY Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 2020 79.5 0 2 2010 79.1 0 3 2016 78.8 0 4 2022 78.1 0 5 2005 78.0 0 6 2018 77.9 0 7 2021 77.5 0 - 1966 77.5 0 8 2006 77.4 0 - 1999 77.4 0 9 2019 77.3 0 - 2012 77.3 0 - 1991 77.3 0 10 1994 77.2 0 Newark 6 top 10 Time Series Summary for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 2022 79.2 0 - 1993 79.2 0 2 2010 78.7 0 3 1994 78.5 0 4 2021 78.3 0 5 2011 78.0 0 6 2005 77.8 0 7 1988 77.7 0 8 2020 77.6 0 - 2016 77.6 0 - 1973 77.6 0 9 1999 77.1 0 10 1995 77.0 0 JFK 7 top 10 warmest Time Series Summary for JFK INTERNATIONAL AIRPORT, NY Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 2010 77.1 0 2 2016 76.5 0 3 2022 76.1 0 4 2015 76.0 0 5 2011 75.8 0 6 2020 75.7 0 7 1983 75.6 0 8 1984 75.4 0 9 2012 75.3 0 - 1991 75.3 0 10 1971 75.2 0 - 1949 75.2 0 BDR 10 top 10 warmest Time Series Summary for IGOR I SIKORSKY MEMORIAL AIRPORT, CT Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 2016 75.4 0 2 2020 75.3 0 3 2010 75.0 0 4 2022 74.4 0 5 2018 74.3 0 6 2021 74.2 0 - 2012 74.2 0 7 2019 74.0 0 - 2011 74.0 0 - 1994 74.0 0 - 1993 74.0 0 8 2005 73.9 0 9 2013 73.8 0 - 1973 73.8 0 10 1949 73.7 0 ISP 10 top 10 warmest Time Series Summary for ISLIP-LI MACARTHUR AP, NY Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 2010 74.7 0 2 2022 74.6 0 - 2020 74.6 0 3 1999 74.5 0 4 2016 74.4 0 5 2011 73.9 0 6 2019 73.8 0 7 2021 73.7 0 8 2018 73.5 0 - 2005 73.5 0 9 2013 73.4 0 10 2012 73.3 0 - 1991 73.3 0

The new EC-AIFS looks like a better defined version of the EPS without the smoothing longer range. It would be great if it can correct some of the long range biases of the Euro and EPS. So it will be interesting to see going forward. https://openmeteo.substack.com/p/artificial-intelligence-weather-model The open-data weather forecasting landscape is experiencing a breath of fresh air with an exciting development the European Centre for Medium-Range Weather Forecasts (ECMWF). ECMWF Opens the Doors to AIFS: In a significant move towards open-data, ECMWF has made data from its cutting-edge artificial intelligence weather model (AIFS) publicly available. Unlike traditional numerical models, AIFS leverages Graph Neural Networks (GNNs), similar to those used in AI image generation, but with significantly more data. This shift, made possible by recent advancements in computing power, allows AIFS to learn complex weather patterns with high accuracy. In recent years, several AI weather models have emerged, with Google's GraphCast gaining attention for surpassing even the world-renowned IFS model. However, AIFS now takes the crown, demonstrating superior accuracy as shown in the provided forecast performance chart below. While all models perform well in the short term (first few days), AI models like AIFS excel in longer-range forecasts, exceeding 5 days. This development is a significant step forward for AI in weather forecasting, paving the way for more accurate and accessible weather information for everyone.

Some stations in the Northeast are over 50 to 1 top 10 warmest to coldest months since 2010.

It didn’t even take 10 years to surpass the CONUS warm record set in 15-16.

Historic pattern of winter warmth since the +13.3 December 2015 continues. This makes it a first 9 warmer to record warm winters in a row. It included 21 out of the last 27 winter months finishing warmer than average. NYC Feb 24…+4.2 Jan 24..+3.3 Dec 23..+5.5 …………..+4.3 Feb 23…+5.2 Jan 23…+9.8 Dec 22…-0.6 …………..+4.8 Feb 22….+1.4 Jan 22….-3.2 Dec 21….+4.7 ……………..+1.0 Feb 21….-1.7 Jan 21….+1.1 Dec 20…+1.7 …………..+0.4 Feb 20…+4.8 Jan 20….+6.5 Dec 19….+0.8 …………….+4.0 Feb 19….+0.9 Jan 19….-0.1 Dec 18…+2.6 …………….+1.1 Feb 18…+6.7 Jan 18….-0.9 Dec 17…..-2.5 …………….+1.1 Feb 17…..+6.3 Jan 17….+5.4 Dec 16….+0.8 …………….+4.2 Feb 16….+2.4 Jan 16….+1.9 Dec 15….+13.3 …………….+5.9

Arctic outbreaks are getting much shorter and covering a smaller geographic region than they used to. We can still get stronger Arctic outbreaks from time to time but they don’ have the lasting power, geographic coverage, and intensity like they did up through around 1994. One of the more interesting events was the Valentines Day Arctic outbreak of 2016. This was the first time an Arctic outbreak below 0° in NYC occurred during a 40° winter. We couldn’t even pull off below 0° during February 2015. So these days we have Arctic outbreaks surrounded by 60° days which was much rarer in the old days when we had much more extended cold. We can remember the brief single digits Arctic shot last winter and the 60° days surrounding. So we can still get very cold days from time to time. But it’s been very difficult since 14-15 to get extended cold. A great example of this was the impressive cold from after Christmas in 2017 into early January. If this had occurred 30 years earlier in a colder climate, then the whole winter would have finished with below normal temperatures. Instead the temperatures rebounded to all-time winter warmth of 80° which was much more impressive vs the long term records that the cold around Christmas was. So the average in February close to 40° resulted in a warmer than average winter.

While it’s always possible to eventually have a colder winter or series of winters again, the coldest winters have been steadily warming over time. None of our colder winters since the late 1970s can come close to a winter like 76-77 for the magnitude and duration of that cold. Our coldest recent winter in 14-15 had 60s on Christmas and NYC averaged 40.5° in December. The last top 10 coldest month in February 2015 was answered by over 30 top 10 warmest months around the region throughout the year since then.

31-32 was a warm outlier for that much colder era. Now we get 40° winter months or 40° average winters nearly every year around NYC. There is much more than background warming occurring when we have seen an historic 9 warmer to record winters in row. The area is more than +3° above any previous 30 year winter average temperature over nearly the last decade. Why is it so hard to believe that CO2 causes the planet to warm up? The first studies were done in the 1800s on this topic. NYC hasn’t had a winter average temperature below 30° since the 1970s. So the much warmer climate makes this an unlikely occurrence barring some major volcanic eruption. As winters have been steadily warming over time, our area has had more all or nothing type snowfall winters since the 1990s. Either above average or below average snowfall with almost no median seasons for places like Long Island. Those more average snowfall seasons were much more common before the 1990s. The risk with the all or nothing track we have been on since the 1990s is that the nothing will become a more common outcome with continued warming. But like we saw in 21-22, we can still score some more above average snowfall seasons along the way. Nearly every snowfall season on Long Island since the 90s has been under 15” or over 30”. The 20s season common before the 90s is almost non-existent at places like Islip.

We could have used these dewpoints in the single digits ahead of some our winter storms. East Hampton MOSUNNY 33 3

Looks like plenty of clouds and rain to go along with the warmer temperatures. We have a strong blocking signal getting met by an overpowering warm Pacific MJO signal. So flooding could eventually become a concern again like we saw before we dried out in February. Could also be more beach erosion with so much high pressure east of New England with easterly flow and lows undercutting. It’s very hard to do warm and dry in a transition month like March with so much volatility. That 80° warmth with dry conditions in early March 2016 after that super El Niño was a real rarity. Our warmest days this March through the first 10 days will probably be 50s and 60s. Maybe someone in the interior away from the marine influence can make a run on 70°. Data for March 10, 2016 through March 11, 2016 Click column heading to sort ascending, click again to sort descending. State Name Station Type Highest Max Temperature NJ CANOE BROOK COOP 82 NJ NEWARK LIBERTY INTL AP WBAN 81 NJ TETERBORO AIRPORT WBAN 81 NJ TETERBORO AIRPORT COOP 81 NJ HARRISON COOP 80 NY SHRUB OAK COOP 80 NY YORKTOWN HEIGHTS 1W COOP 80 NY PORT JERVIS COOP 79 NY NY CITY CENTRAL PARK WBAN 79 NJ CALDWELL ESSEX COUNTY AP WBAN 79 NJ CHARLOTTEBURG RESERVOIR COOP 79 NY WEST POINT COOP 79 NY MOUNT SINAI COOP 79 NY LAGUARDIA AIRPORT WBAN 78 CT SAUGATUCK RESERVOIR COOP 78 CT STAMFORD 5 N COOP 77 NY WESTCHESTER CO AP WBAN 77 NY BAITING HOLLOW COOP 77 NY CENTERPORT COOP 76 NY CARMEL 4N COOP 76 NY SETAUKET STRONG COOP 76 CT MERIDEN MARKHAM MUNICIPAL AP WBAN 75 CT PUTNAM LAKE COOP 75 CT NORWICH PUBLIC UTILITY PLANT COOP 75 NY RIVERHEAD RESEARCH FARM COOP 75 NY UPTON COOP - NWSFO NEW YORK COOP 75

High pressure will dominate east of New England in early March so plenty of easterly flow with clouds and rain potential. It looks like the kind of pattern where the warmer days are into the 50s to lower 60s around EWR and NYC but clouds and onshore flow limit the 70°+ potential for a while near the metro.

Looks like a warm and wet pattern going into March as this is another example of these south based blocks linking up with the Southeast ridge. March 4-11

No problem. I think the reference to 72-73 came up in discussion about this being a rare case of a -PDO with such a strong El Niño. Not that the actual 500 mb and temperature pattern would be a carbon copy. We are even seeing changes with the -PDO due to so much warming in the entire Western Pacific Basin. In addition to the record tropical marine heatwaves in the warmer WPAC MJO phases for us, the ongoing marine heatwave near Japan has been a compounding warm factor also. I saw a great post recently on twitter on how this is a different flavor of -PDO than we used to see before.

I didn’t say 72-73 was a good match for this winter since that was a much colder winter than this one was across North America. We are in such a different global climate state now, that winter analogs before the 15-16 super El Niño are too different. I mostly focused on the record WPAC warm pool for such a strong El Niño presenting warmer risks to the winter computer model forecasts.

One of the strongest leap day cold fronts on record with 50+ mph gusts and heavy convection to possible snow squalls. Temps will quickly fall from the 60s to 20s.