bluewave

Figures that the strongest MJO 8 since December would wait until the start of astronomical spring. So we may have to be really patient for our next 70° day. It could take until April if the models are correct about the next 10 days.

Maybe such an extreme SST rise leading into the El Niño altered the usual timing of the global temperature response surrounding this event.

NYC is on track to make it to the top 10 wettest Marches. Some really hot summers followed years with this much March precipitation. Time Series Summary for NY CITY CENTRAL PARK, NY - Month of Mar Click column heading to sort ascending, click again to sort descending. Rank Year Total Precipitation Missing Count 1 2010 10.69 0 2 1983 10.54 0 3 1980 10.41 0 4 1876 8.79 0 5 1953 8.76 0 6 1912 7.70 0 7 2001 7.48 0 8 1977 7.41 0 9 1993 6.64 0 10 1913 6.47 0 11 1994 6.33 0 12 1984 6.30 0 13 2011 6.19 0 14 1933 6.08 0 15 1944 5.98 0 16 1967 5.97 0 17 1919 5.96 0 18 1942 5.91 0 19 1932 5.82 0 20 1881 5.81 0 21 1899 5.77 0 22 1974 5.76 0 23 1951 5.62 0 24 1877 5.56 0 25 1871 5.54 0 26 1922 5.52 0 27 1890 5.50 0 28 1901 5.47 0 29 1936 5.45 0 30 2007 5.35 0 31 1896 5.28 0 32 2017 5.25 0 33 1872 5.24 0 34 1997 5.18 0 35 2018 5.17 0 36 1991 5.16 0 37 1998 5.08 0 38 1956 5.03 0 39 1906 5.01 0 40 2005 4.96 0 41 1989 4.93 0 - 1987 4.93 0 43 1902 4.84 0 44 1931 4.83 0 45 1968 4.79 0 46 1939 4.78 0 47 1920 4.75 0 48 1914 4.74 0 49 1940 4.73 0 50 2015 4.72 0 51 1880 4.66 0 52 1888 4.62 0 - 1884 4.62 0 54 1869 4.61 0 55 2024 4.57 12

The timing of the jump in temperatures this year was related to the onset of the El Niño. But the magnitude of warmth was a function of the record heat being released from the oceans. Much more heat available this El Niño than previous ones. So even a significantly weaker El Niño than 2015-16 had more warming potential. But it will still take more research specifically as to why this lead to a sharper temperature increase earlier in the year than past El Niño events.

My guess is that this warming spike is related to the rapid subtropical SST warming which has occurred since the last super El Niño in 15-16. https://www.nature.com/articles/s43247-023-00839-w In this study, we evaluate the ocean warming pattern derived from four decades of satellite measurements. We find widespread strong subtropical ocean warming, concentrating mostly on the western ocean basins. In contrast to these observations, studies of paleoclimate suggest that the greatest ocean warming occurs at higher latitudes. By pairing the observed warming pattern with SST evolution in long-term climate simulations, we propose that the observed warming pattern is constrained by ocean dynamics of surface convergence (downwelling, subtropical gyres) and divergence (upwelling, subpolar gyres) rather than being dominated by internal variabilities, such as the PDO. This pattern emerges only at the early stage (a few decades) of anthropogenic warming when absorption of heat concentrates in the upper ocean. On centennial (for the Northern Pacific Ocean) to millennial (for the North Atlantic Ocean and Southern Hemisphere) timescales, when deep ocean water warms, the greatest ocean warming is expected to occur in the subpolar region, as indicated by paleo-reconstructions and the long-term and equilibrium climate simulations.

Extremely steep lapse rates and some CAPE should allow for gusts over 40 and small hail with the convection later today.

In general, the 2023 temperature anomaly has come out of the blue, revealing an unprecedented knowledge gap perhaps for the first time since about 40 years ago, when satellite data began offering modellers an unparalleled, real-time view of Earth’s climate system. If the anomaly does not stabilize by August — a reasonable expectation based on previous El Niño events — then the world will be in uncharted territory. It could imply that a warming planet is already fundamentally altering how the climate system operates, much sooner than scientists had anticipated. It could also mean that statistical inferences based on past events are less reliable than we thought, adding more uncertainty to seasonal predictions of droughts and rainfall patterns. Much of the world’s climate is driven by intricate, long-distance links — known as teleconnections — fuelled by sea and atmospheric currents. If their behaviour is in flux or markedly diverging from previous observations, we need to know about such changes in real time. We need answers for why 2023 turned out to be the warmest year in possibly the past 100,000 years. And we need them quickly. Nature 627, 467 (2024) doi: https://doi.org/10.1038/d41586-024-00816-z

The 1980s and 1990s were no comparison to the warmth and lack of snow during the 2020s so far. I will use LGA stats to compare since NYC has been consistently undermeasuring snowfall. While we are only half way through the 2020s, we would need a significant cool down and snowfall increase next 5 years to avoid the warmest and least snowiest decade on record. If global and local temperatures continue rising at the same rate, then we will eventually have a whole decade with the average snowfall under 10” and the average winter temperature over 40.0°. LGA 2020s so far snowfall average….15.8”….DJF ave temp…39.2° ………1990s………..27.1”………………………….36.7° ………1980s………..21.0”…………………………34.5°

Yeah, it would be interesting to see specifically which aspect of the warming in the system lead to this outcome. Notice the extreme volatility of the AO between positive and negative. Maybe the IO to WPAC MJO driven Rossby wave train competing with the El Niño was interfering with the coupling. So every drop of the -AO was answered by and quick increase.

Yeah, beach erosion and coastal flooding have become the new normal with the more extreme storms and rising sea levels.

Much more model spread than we typically see around 5 days out. The potential for heavy rains is there if everything gels. But this is a lower confidence forecast than usual since cutoffs in spring are the hardest for models to resolve. Each model has a different low position at 120 hrs.

They did much better last March with the -NAO and record MJO 8.

Gorgeous photos of the roll clouds on the South Shore yesterday. https://www.facebook.com/permalink.php?story_fbid=pfbid0ehVZDaAGaxnLjfGngNWK82TSG5WHZYNaYbRUhBtJ3u6WtsFnrfUuyyhYjH31z153l&id=100000492031103

It’s the areas that sustain a hard freeze in the mid 20s that are most susceptible to plant damage after an early bloom. https://hortnews.extension.iastate.edu/faq/hard-freeze-early-spring-damaged-newly-emerged-growth-several-trees-and-shrubs-will-plants Question: A hard freeze in early spring damaged the newly emerged growth on several trees and shrubs. Will the plants recover? Answer: Newly emerged tree and shrub foliage is susceptible to damage from below freezing temperatures. The new growth on many trees and shrubs can tolerate temperatures in the low 30s and upper 20s. Freeze damage is most likely when temperatures drop into the middle 20s or below. Symptoms of freeze damage include shriveling and browning or blackening of damaged tissue. Damaged growth usually becomes limp. Eventually, damaged or destroyed leaves drop from the tree or shrub. Fortunately, trees and shrubs have the ability to leaf out again if the initial growth is damaged or destroyed. Damaged trees and shrubs have only suffered a temporary setback. Healthy, well established trees and shrubs will produce additional growth within a few weeks. Good care during the remainder of the year, such as watering during dry periods, should aid the recovery of trees and shrubs planted within the past two or three years.

The Seattle forecast zones actually got to 80° before our area this March.

Yeah, March was more like a winter month during the 2010s and now it’s a spring month in the 2020s. So it’s a challenge reaching normal seasonal snowfall when we don’t get much snow these days in December and March since they have become so warm. Very hard to get to normal when you are just relying on January and February. Plus the warmth has been encroaching on those months also reducing snowfall potential. So a continuation of our climate becoming more like what areas to our south in the Mid-Atlantic used to be like in the old days.

NYC will need to see some snowfall improvement the next 5 years for the 2020s to avoid being the lowest snowfall decade following the highest during the 2010s since 1950. Monthly Total Snowfall for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Year Oct Nov Dec Jan Feb Mar Apr Season Mean 0.0 T 2.6 4.4 7.1 0.1 T 14.2 2023-2024 0.0 T T 2.3 5.2 T M 7.5 2022-2023 0.0 0.0 T T 2.2 0.1 0.0 2.3 2021-2022 0.0 T 0.2 15.3 2.0 0.4 0.0 17.9 2020-2021 0.0 0.0 10.5 2.1 26.0 T 0.0 38.6 2019-2020 0.0 0.0 2.5 2.3 T T T 4.8 Monthly Total Snowfall for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Year Oct Nov Dec Jan Feb Mar Apr Season Mean 0.3 1.1 5.3 12.9 11.8 6.0 0.6 37.9 2018-2019 0.0 6.4 T 1.1 2.6 10.4 0.0 20.5 2017-2018 0.0 T 7.7 11.2 4.9 11.6 5.5 40.9 2016-2017 0.0 T 3.2 7.9 9.4 9.7 0.0 30.2 2015-2016 0.0 0.0 T 27.9 4.0 0.9 T 32.8 2014-2015 0.0 0.2 1.0 16.9 13.6 18.6 0.0 50.3 2013-2014 0.0 T 8.6 19.7 29.0 0.1 T 57.4 2012-2013 0.0 4.7 0.4 1.5 12.2 7.3 0.0 26.1 2011-2012 2.9 0.0 0.0 4.3 0.2 0.0 0.0 7.4 2010-2011 0.0 T 20.1 36.0 4.8 1.0 T 61.9 2009-2010 0.0 0.0 12.4 2.1 36.9 T 0.0 51.4 Monthly Total Snowfall for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Year Oct Nov Dec Jan Feb Mar Apr Season Mean T T 6.6 7.2 10.1 3.5 0.5 28.0 2008-2009 0.0 T 6.0 9.0 4.3 8.3 T 27.6 2007-2008 0.0 T 2.9 T 9.0 T 0.0 11.9 2006-2007 0.0 0.0 0.0 2.6 3.8 6.0 T 12.4 2005-2006 0.0 T 9.7 2.0 26.9 1.3 0.1 40.0 2004-2005 0.0 T 3.0 15.3 15.8 6.9 0.0 41.0 2003-2004 0.0 0.0 19.8 17.3 0.7 4.8 0.0 42.6 2002-2003 T T 11.0 4.7 26.1 3.5 4.0 49.3 2001-2002 0.0 0.0 T 3.5 T T T 3.5 2000-2001 T 0.0 13.4 8.3 9.5 3.8 0.0 35.0 1999-2000 0.0 0.0 T 9.5 5.2 0.4 1.2 16.3 Monthly Total Snowfall for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Year Oct Nov Dec Jan Feb Mar Apr Season Mean 0.0 0.8 3.0 6.1 8.7 5.7 0.1 24.4 1998-1999 0.0 0.0 2.0 4.5 1.7 4.5 0.0 12.7 1997-1998 0.0 T T 0.5 0.0 5.0 0.0 5.5 1996-1997 0.0 0.1 T 4.4 3.8 1.7 T 10.0 1995-1996 0.0 2.9 11.5 26.1 21.2 13.2 0.7 75.6 1994-1995 0.0 T T 0.2 11.6 T T 11.8 1993-1994 0.0 T 6.9 12.0 26.4 8.1 0.0 53.4 1992-1993 0.0 0.0 0.4 1.5 10.7 11.9 0.0 24.5 1991-1992 0.0 T 0.7 1.5 1.0 9.4 T 12.6 1990-1991 0.0 0.0 7.2 8.4 9.1 0.2 0.0 24.9 1989-1990 0.0 4.7 1.4 1.8 1.8 3.1 0.6 13.4 Monthly Total Snowfall for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Year Oct Nov Dec Jan Feb Mar Apr Season Mean T 0.1 2.3 7.9 5.4 3.0 1.0 19.7 1988-1989 0.0 0.0 0.3 5.0 0.3 2.5 0.0 8.1 1987-1988 0.0 1.1 2.6 13.9 1.5 T 0.0 19.1 1986-1987 0.0 T 0.6 13.6 7.0 1.9 0.0 23.1 1985-1986 0.0 T 0.9 2.2 9.9 T T 13.0 1984-1985 0.0 T 5.5 8.4 10.0 0.2 T 24.1 1983-1984 0.0 T 1.6 11.7 0.2 11.9 0.0 25.4 1982-1983 0.0 0.0 3.0 1.9 21.5 T 0.8 27.2 1981-1982 0.0 0.0 2.1 11.8 0.4 0.7 9.6 24.6 1980-1981 0.0 T 2.8 8.0 T 8.6 0.0 19.4 1979-1980 T 0.0 3.5 2.0 2.7 4.6 T 12.8 Monthly Total Snowfall for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Year Oct Nov Dec Jan Feb Mar Apr Season Mean T 0.3 2.0 8.0 9.9 2.3 0.1 22.5 1978-1979 0.0 2.2 0.5 6.6 20.1 T T 29.4 1977-1978 0.0 0.2 0.4 20.3 23.0 6.8 T 50.7 1976-1977 0.0 T 5.1 13.0 5.8 0.6 T 24.5 1975-1976 0.0 T 2.3 5.6 5.0 4.4 T 17.3 1974-1975 0.0 0.1 0.1 2.0 10.6 0.3 T 13.1 1973-1974 0.0 0.0 2.8 7.8 9.4 3.2 0.3 23.5 1972-1973 T T T 1.8 0.8 0.2 T 2.8 1971-1972 0.0 T T 2.8 17.8 2.3 T 22.9 1970-1971 0.0 0.0 2.4 11.4 T 1.3 0.4 15.5 1969-1970 0.0 T 6.8 8.4 6.4 4.0 T 25.6 Monthly Total Snowfall for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Year Oct Nov Dec Jan Feb Mar Apr Season Mean T 0.4 8.3 7.1 10.1 6.1 0.1 32.0 1968-1969 0.0 T 7.0 1.0 16.6 5.6 0.0 30.2 1967-1968 0.0 3.2 5.5 3.6 1.1 6.1 0.0 19.5 1966-1967 0.0 0.0 9.1 1.4 23.6 17.4 T 51.5 1965-1966 T 0.0 T 11.6 9.8 T 0.0 21.4 1964-1965 0.0 0.0 3.1 14.8 2.5 2.8 1.2 24.4 1963-1964 0.0 T 11.3 13.3 14.1 6.0 T 44.7 1962-1963 T T 4.5 5.3 3.7 2.8 T 16.3 1961-1962 0.0 T 7.7 0.6 9.6 0.2 T 18.1 1960-1961 T 0.0 18.6 16.7 18.2 1.2 T 54.7 1959-1960 0.0 0.5 15.8 2.5 1.9 18.5 0.0 39.2 Monthly Total Snowfall for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Year Oct Nov Dec Jan Feb Mar Apr Season Mean 0.1 0.5 3.3 4.8 4.0 6.2 1.0 19.9 1958-1959 0.0 T 3.8 1.5 0.4 6.7 0.6 13.0 1957-1958 0.0 T 8.7 9.2 10.7 15.9 0.2 44.7 1956-1957 0.0 T 0.9 8.9 7.0 2.6 2.5 21.9 1955-1956 0.0 1.0 3.3 1.2 2.7 21.1 4.2 33.5 1954-1955 0.0 T 0.1 2.6 5.2 3.6 0.0 11.5 1953-1954 0.0 2.2 T 12.7 0.5 0.1 0.3 15.8 1952-1953 0.5 1.7 7.5 4.1 0.4 0.9 T 15.1 1951-1952 0.0 T 3.3 6.2 2.8 7.4 0.0 19.7 1950-1951 0.0 T 3.8 0.9 1.9 2.7 0.0 9.3 1949-1950 0.0 0.5 1.3 0.4 8.5 1.4 1.9 14.0

March was more like a winter month during the 2010s and is now a spring month In the 2020s. Monthly Mean Avg Temperature for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Year Mar Season Mean 46.5 46.5 2024 48.7 48.7 2023 44.6 44.6 2022 45.3 45.3 2021 45.8 45.8 2020 48.0 48.0 Monthly Total Snowfall for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Year Mar Season Mean 0.1 0.1 2024 T T 2023 0.1 0.1 2022 0.4 0.4 2021 T T 2020 T T Monthly Mean Avg Temperature for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Year Mar Season Mean 42.7 42.7 2019 41.7 41.7 2018 40.1 40.1 2017 39.2 39.2 2016 48.9 48.9 2015 38.1 38.1 2014 37.7 37.7 2013 40.1 40.1 2012 50.9 50.9 2011 42.3 42.3 2010 48.2 48.2 Monthly Total Snowfall for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Year Mar Season Mean 6.0 6.0 2019 10.4 10.4 2018 11.6 11.6 2017 9.7 9.7 2016 0.9 0.9 2015 18.6 18.6 2014 0.1 0.1 2013 7.3 7.3 2012 0.0 0.0 2011 1.0 1.0 2010 T T

Looks like mid-70s for the warm spots in NJ west of the sea breeze today.

NYC only needs another 2.00” of rain for a top 10 wettest March. So a rainy period later in the month can push NYC into the top 10.

Looks like only scattered showers with the frontal passages over the next week or so. This will translate into below average rainfall with no very heavy rainfalls of several inches expected. Then we shift back to a wetter pattern later in the month as it’s been tough to sustain any drier intervals since last summer.

3 of the top 5 warmest first 2 weeks of March have occurred since the 15-16 super El Niño. 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 14 Missing Count 1 2020-03-14 49.0 0 2 1977-03-14 48.5 0 3 2024-03-14 48.2 2 4 2016-03-14 47.9 0 5 2012-03-14 47.6 0

Too bad the phase wasn’t a little further southeast allowing a benchmark track instead.

UHI isn’t a factor for record cold like that since NYC has needed strong CAA back to around 1900 when UHI became established. It’s that the air masses aren’t as cold anymore as they were as recently as the late 70s to early 90s. Newark had one of their coldest readings of all time as recently as the 1980s while UHI was well established. NYC has always needed northerly flow for the few times it got below -10°. UHI mostly means that on nights with calm winds and clear skies the surrounding areas will radiate much better. But the best Arctic outbreaks in NYC always need strong winds to transport the Arctic air from the north and west. That’s why there isn’t that much difference between NYC and nearby less urban stations when the winds stay strong. It’s on the nights when the winds are calm that we see the big disparity. Time Series Summary for NEWARK LIBERTY INTL AP, NJ - Jan through Dec Click column heading to sort ascending, click again to sort descending. Rank Year Lowest Min Temperature Missing Count 1 1934 -14 0 2 1985 -8 0 - 1933 -8 0 3 1982 -7 0 - 1943 -7 0 4 1936 -4 0 - 1935 -4 0 5 1994 -2 0 - 1977 -2 0 - 1963 -2 0 - 1961 -2 0 6 1984 -1 0 - 1981 -1 0 - 1980 -1 0 - 1979 -1 0 - 1976 -1 0 - 1942 -1 0 7 2016 0 0 - 2004 0 0 - 1957 0 0 - 1945 0 0

It’s easy to beat guidance on days like these when we get clear skies and downslope flow with dewpoints in the 20s. Central Park SUNNY 66 25 21 W13G23