bluewave

1993 was the leader in 95° and 100° days at Newark. You can see how much warmer our summers have become since 2010. Even though 2010 and 1993 still stand at the top, many other years haven’t been far behind. This is mostly due to the onshore flow influence. If we ever got westerly flow and a real summer drought, then this records would easily be eclipsed in this much warmer climate than 2010 and 1993. 95° days at Newark Time Series Summary for NEWARK LIBERTY INTL AP, NJ - Jan through Dec Click column heading to sort ascending, click again to sort descending. 1 1993 25 0 2 2010 21 0 3 2022 20 0 - 1988 20 0 - 1944 20 0 4 2021 18 0 5 2012 17 0 - 2011 17 0 - 2002 17 0 - 1955 17 0 6 1949 16 0 7 2005 14 0 - 1953 14 0 8 2016 13 0 - 1999 13 0 - 1991 13 0 - 1987 13 0 9 1994 12 0 - 1983 12 0 - 1966 12 0 10 2018 11 0 - 1973 11 0 100° days Time Series Summary for NEWARK LIBERTY INTL AP, NJ - Jan through Dec Click column heading to sort ascending, click again to sort descending. 1 1993 9 0 2 1949 8 0 3 2022 6 0 - 1953 6 0 4 1988 5 0 - 1966 5 0 5 2011 4 0 - 2010 4 0 - 1955 4 0 - 1944 4 0

95° and 100° days were close in 2022 to 2010 in NJ. 2022 95° days Data for January 1, 2022 through December 31, 2022 Click column heading to sort ascending, click again to sort descending. Newark Area ThreadEx 20 NEWARK LIBERTY INTL AP WBAN 20 FREEHOLD-MARLBORO COOP 16 HARRISON COOP 16 SOUTH JERSEY REGIONAL AIRPORT WBAN 16 CANOE BROOK COOP 14 LONG BRANCH-OAKHURST COOP 13 SOMERSET AIRPORT WBAN 13 HIGHTSTOWN 2 W COOP 12 INDIAN MILLS 2 W COOP 10 NEW BRUNSWICK 3 SE COOP 10 CALDWELL ESSEX COUNTY AP WBAN 10 ESTELL MANOR COOP 10 New Brunswick Area ThreadEx 10 MANASQUAN 1 NW COOP 10 NJ 100° days Data for January 1, 2022 through December 31, 2022 Click column heading to sort ascending, click again to sort descending. NEWARK LIBERTY INTL AP WBAN 6 Newark Area ThreadEx 6 SOMERSET AIRPORT WBAN 5 FREEHOLD-MARLBORO COOP 5 CANOE BROOK COOP 4 HARRISON COOP 4 2010 95° days Data for January 1, 2010 through December 31, 2010 Click column heading to sort ascending, click again to sort descending. WRIGHTSTOWN COOP 24 SOMERDALE 4 SW COOP 22 Newark Area ThreadEx 21 NEWARK LIBERTY INTL AP WBAN 21 MOORESTOWN 4 E COOP 19 ATLANTIC CITY INTL AP WBAN 18 Atlantic City Area ThreadEx 18 CANOE BROOK COOP 18 RINGWOOD COOP 18 ESTELL MANOR COOP 18 TRENTON-MERCER AIRPORT WBAN 17 Trenton Area ThreadEx 17 HARRISON COOP 16 SOUTH JERSEY REGIONAL AIRPORT WBAN 16 PENNSAUKEN 1N COOP 16 FREEHOLD-MARLBORO COOP 15 NEW BRUNSWICK 3 SE COOP 15 New Brunswick Area ThreadEx 15 2010 100° days Data for January 1, 2010 through December 31, 2010 Click column heading to sort ascending, click again to sort descending. Newark Area ThreadEx 4 WRIGHTSTOWN COOP 4 NEWARK LIBERTY INTL AP WBAN 4 HARRISON COOP 4 Trenton Area ThreadEx 3 FREEHOLD-MARLBORO COOP 3 TRENTON-MERCER AIRPORT WBAN 3 CANOE BROOK COOP 3 RINGWOOD COOP 3 SOMERDALE 4 SW COOP 3

Of course 90° days are increasing in the city. I showed you how the drop in 90° days is a function of measuring the temperatures under the trees in Central Park since 1995. Several areas had their warmest summer on record for 90° days as recently as 2022. The immediate South Shore isn’t representative of what most of this forum experiences in the summer. This is a function of the ridge extending east of New England and turning the flow more onshore. So the sea breeze fronts have been setting up north of JFK and the Southern State Parkway on Long Island. Very rare in recent years for the sea breeze fronts to remain along the South Shore beaches like they did from the 1990s to 2013. https://mesonet.agron.iastate.edu/plotting/auto/?_wait=no&q=74&network=CTCLIMATE&station=CT1762&season=all&dir=above&var=high&threshold=90&year=1950&_r=t&dpi=100&_fmt=png

90° days have been increasing across the entire region. The only areas that haven’t seen a big increase are at near the immediate shore. But most people live away from the immediate shore areas.

Yeah, spring 90° days at Newark have been increasing at a much slower rate than 50° and 60° days during the winter. https://mesonet.agron.iastate.edu/plotting/auto/?_wait=no&q=74&network=NJCLIMATE&station=NJTEWR&season=winter&dir=above&var=high&threshold=50&year=1893&_r=t&dpi=100&_fmt=png

Looks like another over the top warm up this week. We could actually see the heaviest rains to our south instead of to the north which is different from the recent pattern. Then we cool down closer to average for late May with the wet pattern continuing. May 12-19 May 19-26

When you look at the regional increase in 90 days, NYC is the only outlier. LGA has seen a slower increase in 90° days than New Brunswick which is in a more rural to suburban type setting with grass and nearby trees. The base period that I am using for comparison is 1961-1990. This is the base period many of us grew up in before the summers and other seasons began to rapidly warm. So it was the last time we had anything approximating a stable climate. Summer warming especially accelerated from 2010 to 2024. 12 out of those 15 summers were above normal warmth to record warmth across the area. We only had 3 summers near to slightly below average temperatures in 2014, 2017, and 2023. The last time we had an actual cool summer was back in 2009. NYC has only seen an increase of 5.5% in the number of 90° days. Newark is at a 43.5% increase. LGA has increased 78.5%. New Brunswick has jumped 93.7%. POU to our north has seen a 50% increase. So NYC is the obvious outlier. LGA has been subject to cooling breezes off the water in recent summers since the ASOS is right on the water. There have been several more 90° days to the south closer to Corona, Queens. Newark has also had several summers recently with more onshore flow. This is why areas to the west have seen more 90° days. If the NYC ASOS wasn’t moved into the shade back in 1995, then the average would be at around 29 days reaching a year now vs 19. So this does a big disservice to residents living in Manhattan where the number of 90° days has been getting undercounted. I arrived at 29 days since this represents around a 60% increase when the Newark and LGA rate of increase is averaged out. So this is what the actual NYC annual number of 90° days would be closer to if the measurements were taken in a clearing like the Great Lawn rather than in a dense area of vegetation under a tall stand of cool shade trees. 1961 -1990 to 2010-2024 change in 90° days NYC….18 to 19……..+5.5% EWR….23 to 33……..+43.5% LGA…..14 to 25……..+78.5% NBW….16 to 31……..+93.7%…….My abbreviation for New Brunswick POU…..14 to 21……..+50%

Yeah, moving the ASOS into the shade in 1995 really skewed the values. In the roughly 30 year period since 1996 NYC has had only 461 days reaching 90 vs 817 days at Newark and 631 at LGA. The previous 30 year period from 1961 to 1990 featured 550 days in NYC with 689 at Newark and 410 at LGA. Harrison has become the new 90° day leader across the area surpassing Plainfield from 1961-1990. 1961-1990 # of 90 days EWR….689 NYC….550 LGA….410 1996-2024 #90 days EWR…817 LGA…631 NYC…461 Data for January 1, 1996 through December 31, 2024 Click column heading to sort ascending, click again to sort descending. NJ HARRISON COOP 871 NJ CANOE BROOK COOP 836 NJ NEWARK LIBERTY INTL AP WBAN 817 NJ TETERBORO AIRPORT WBAN 778 NY LAGUARDIA AIRPORT WBAN 631 NJ CALDWELL ESSEX COUNTY AP WBAN 589 NJ TETERBORO AIRPORT COOP 512 CT DANBURY COOP 498 NJ CRANFORD COOP 485 NY NY CITY CENTRAL PARK WBAN 461 Data for January 1, 1961 through December 31, 1990 Click column heading to sort ascending, click again to sort descending. NJ PLAINFIELD COOP 724 NJ NEWARK LIBERTY INTL AP WBAN 689 NY NEW YORK LAUREL HILL COOP 645 NJ LITTLE FALLS COOP 635 NY WEST POINT COOP 614 NY NY CITY CENTRAL PARK WBAN 550 NY NY WESTERLEIGH STAT IS COOP 536 NY SCARSDALE COOP 523 NJ CANOE BROOK COOP 521 NJ CRANFORD COOP 468 NJ ESSEX FELLS SERVICE BLDG COOP 455 NY DOBBS FERRY-ARDSLEY COOP 454 NJ WANAQUE RAYMOND DAM COOP 443 NY NEW YORK AVE V BROOKLYN COOP 438 NY LAGUARDIA AIRPORT WBAN 410

There is actually a cool bias at times at Newark since the ASOS is right on the water and gets a sea breeze. You will notice several more inland NJ sites having a similar number or more 90° days than Newark does. This is the total 90° count for the 2020s in NJ so far with the Harrison and Hightstown beating Newark for 90° days. 90 day Data for January 1, 2020 through May 9, 2025 Click column heading to sort ascending, click again to sort descending. HIGHTSTOWN 2 W COOP 204 HARRISON COOP 195 Newark Area ThreadEx 183 NEWARK LIBERTY INTL AP WBAN 183 CANOE BROOK COOP 173 FREEHOLD-MARLBORO COOP 170 ESTELL MANOR COOP 169 SOMERSET AIRPORT WBAN 167 CALDWELL ESSEX COUNTY AP WBAN 162 SOUTH JERSEY REGIONAL AIRPORT WBAN 160 New Brunswick Area ThreadEx 154 NEW BRUNSWICK 3 SE COOP 154

Yeah, we’ll see how it goes. But it does look like 90° potential will probably wait until after the Memorial Day weekend. While recent years had under 40 days at Newark with the first 90° holding off until after June 1st, the last time the first 90° getting delayed into June reached 40 days was 1983. But that was after a super El Niño winter and not a La Niña like this year. The real test will probably come during the last week of May which is beyond the 15 day model range. If a 90° day can’t sneak in that week, then the chances for Newark reaching 40 days this year could be diminished based on the past. All years at Newark with 40 days reaching 90° and the 1st 90° day 2010….54….4-7 2022….49….5-21 1993…..49….5-9 1988….43…..5-31 2021....41……5-19 1991….41……5-12 2016...40…..5-25 1983…40…..6-12 1959….40…..5-12

Looks like a delayed first 90° of the season for the warm spots like Newark. Models still have the upper low sitting over the Northeast on Memorial Day weekend. If this forecast does indeed verify, then it could mean that a summer like 2021 and 2022 for over 40 days reaching 90° near Newark may be less likely. This was the case in 2020 with the delayed first 90° into early June signaling fewer 90° days overall. These days Newark needs 40 or more days reaching 90° to be considered to be a high number. First/Last Summary for NEWARK LIBERTY INTL AP, NJ Each section contains date and year of occurrence, value on that date. Click column heading to sort ascending, click again to sort descending. Minimum 04-13 (2023) 08-27 (2020) 81 Mean 05-16 09-11 118 Maximum 06-06 (2020) 10-02 (2019) 147 2024 05-02 (2024) 90 08-28 (2024) 95 117 2023 04-13 (2023) 92 09-08 (2023) 92 147 2022 05-21 (2022) 95 09-04 (2022) 93 105 2021 05-19 (2021) 91 09-15 (2021) 91 118 2020 06-06 (2020) 91 08-27 (2020) 93 81 2019 05-26 (2019) 90 10-02 (2019) 96 128 2018 05-02 (2018) 90 09-06 (2018) 98 126 2017 05-17 (2017) 92 09-25 (2017) 90 130 2016 05-25 (2016) 91 09-23 (2016) 90 120 2015 05-25 (2015) 90 09-09 (2015) 91 106 Time Series Summary for NEWARK LIBERTY INTL AP, NJ - Jan through Dec Click column heading to sort ascending, click again to sort descending. 2024 33 0 2023 29 0 2022 49 0 2021 41 0 2020 31 0 2019 27 0 2018 36 0 2017 22 0 2016 40 0 2015 35 0

The NAO and AO have become really volatile over the years. With big swings from positive to negative over very short periods. So trying to do a detailed long range AO and and NAO forecast for next winter would probably be low skill at this point. This past winter the AO was negative and the NAO positive. This decoupling between the 2 indices has become more common during the 2020s. Plus on the days with .25 and more of precipitation around NYC this last winter the -AO and -NAO linked up with the Southeast Ridge. My guess is that this is related to surface pressures rising near the Azores during the winter. When the -AO links up with the Southeast Ridge the AO still registers as negative. But when the blocking near Iceland and Greenland links up with the East Atlantic or European Subtropical Ridge, the NAO registers as positive. So the rising pressures to the south near Europe have been preventing more -NAO winters in recent years. If we had lower pressures near the Azores this past winter, then it would have been a -NAO winter since pressures were above average near Iceland. Notice how much different it was from the pattern in 2010 with the record -NAO. The shift to a much more positive EA over time seems to have been also influencing the NAO. https://www.cpc.ncep.noaa.gov/data/teledoc/ea.shtml

While the records only go back to 1998, parts Orange County NY are already the 7th wettest May on record. Time Series Summary for MONTGOMERY ORANGE COUNTY AP, NY - Month of May Click column heading to sort ascending, click again to sort descending. 1 1998 6.80 0 2 2002 6.54 0 3 2011 5.39 0 4 2003 4.98 0 5 2024 4.94 0 6 2017 4.83 0 7 2025 4.77 23 8 2009 4.53 0 9 2021 4.50 0 10 2019 4.44 3

The jet stream weakening after the winter and plenty of blocking in Canada allowing lows to cutoff underneath.

We discussed this over the winter with the October to winter MJO relationship. La Niña mismatches with a strong +PNA out of the gate in December set the tone for those winters. We saw this in 1995-1996, 2000-2001, 2017-2018, 2020-2021, and 2024-2025. The La Niñas or cold neutrals surrounding these were warmer. But we missed out on the heavy snows last winter and much colder readings like we had in the past due to the much stronger Northern Stream of Pacific Jet. So the cold and snow last winter was a big underperformer in this new warmer and less snowy climate The data I am using suggests a rebound in temperatures for next winter based on what I am currently seeing. Plus we haven’t had back to back October MJO indicators like last year. But if we see more amplitude again next October then, I could reconsider my early first guess. But it would require a first in 30 years. The snowfall was so low from Philly to NYC last winter that it wouldn’t take much to come close or even exceed it. My final call on that will have to wait until I see the December early snowfall indicator. Also notice how scarce even months closer to average temperature to a little cooler than average like this past winter have become. We quickly saw a big rebound in temperatures this spring with the warm departures greatly exceeding the cold ones. This is to be expected since the geographic extent of the cold last winter was extremely limited. This is why the Northeast has seen over 50 top 10 warmest months since 2010 to only 1 top 10 coldest.

The extended EPS has this rainy pattern into late May. We may continue the recent years pattern of rain on at least one of the Memorial Day weekend days. As the upper low will still be near the Northeast.

My guess is that next winter will be warmer than this last one was from Philly to Boston. Every La Nina with such a strong +PNA in December had winters around it which were warmer. But since the snowfall was so low anyway, there is a chance that one larger snowstorm if it should occur could rival or exceed last winter from Philly to Boston. I will update again after we see what clues we get in October.

Yeah, the Southeast Ridge or WAR has been very strong this month. So the heaviest rains were pushed up further north than the I-78 to I-80 corridor. Looks like a repeat performance for the next few days.

It already has. The very strong 500mb ridge has returned to the east of Japan and south of the Aleutians this spring. Also notice the Southeast Ridge or Western Atlantic Ridge linking up again with the Greenland to Iceland blocking.

The strong onshore flow kept the upper 80s heat to our West. for May 1, 2025 through May 7, 2025 Click column heading to sort ascending, click again to sort descending. OCEAN COUNTY AIRPORT WBAN 89 Newark Area ThreadEx 88 NEWARK LIBERTY INTL AP WBAN 88 HARRISON COOP 88 TETERBORO AIRPORT COOP 87 TETERBORO AIRPORT WBAN 87 ESTELL MANOR COOP 87 SOMERSET AIRPORT WBAN 86 PHILADELPHIA/MT. HOLLY WFO COOP 86 New Brunswick Area ThreadEx 86 HIGHTSTOWN 2 W COOP 86 NEW BRUNSWICK 3 SE COOP 86 CALDWELL ESSEX COUNTY AP WBAN 86 Atlantic City Area ThreadEx 85 PENNSAUKEN 1N COOP 85 MILLVILLE MUNICIPAL AIRPORT WBAN 85 ATLANTIC CITY INTL AP WBAN 85 MOORESTOWN 4 E COOP 85 FREEHOLD-MARLBORO COOP 85 EWING 3 WNW COOP 85 FLEMINGTON 5 NNW COOP 85 SOUTH JERSEY REGIONAL AIRPORT WBAN 85 Trenton Area ThreadEx 84 MARGATE COOP 84 MANASQUAN 1 NW COOP 84 LONG BRANCH-OAKHURST COOP 84 TRENTON-MERCER AIRPORT WBAN 84 SUSSEX AIRPORT WBAN 83 CHARLOTTEBURG RESERVOIR COOP 83 SCHOOLEY'S MOUNTAIN 1 SW COOP 81 BOONTON 1 SE COOP 81 HIGHLAND LAKES 1SW COOP 80 Data for May 1, 2025 through May 7, 2025 Click column heading to sort ascending, click again to sort descending. NJ NEWARK LIBERTY INTL AP WBAN 88 NJ HARRISON COOP 88 NY LAGUARDIA AIRPORT WBAN 87 NJ TETERBORO AIRPORT WBAN 87 NJ TETERBORO AIRPORT COOP 87 NJ CALDWELL ESSEX COUNTY AP WBAN 86 NY NY CITY CENTRAL PARK WBAN 85 NJ CHARLOTTEBURG RESERVOIR COOP 83 NY SHRUB OAK COOP 83 NY WESTCHESTER CO AP WBAN 83 NY PORT JERVIS COOP 82 NY MONTGOMERY ORANGE COUNTY AP WBAN 82 CT DANBURY MUNICIPAL AP WBAN 82 NY CENTERPORT COOP 82 NY PORT AUTH DOWNTN MANHATTAN WALL ST HEL ICAO 81 NY BAITING HOLLOW COOP 81 CT MERIDEN MARKHAM MUNICIPAL AP WBAN 81 CT OXFORD WATERBURY WBAN 79 NY SYOSSET COOP 79 CT NORWICH PUBLIC UTILITY PLANT COOP 79 NY RIVERHEAD RESEARCH FARM COOP 78 NY JFK INTERNATIONAL AIRPORT WBAN 77 NY ST. JAMES COOP 76 NY ISLIP-LI MACARTHUR AP WBAN 76 NY FARMINGDALE REPUBLIC AP WBAN 75 NY SHIRLEY BROOKHAVEN AIRPORT WBAN 75 NY UPTON COOP - NWSFO NEW YORK COOP 75 CT NEW HAVEN TWEED AP WBAN 74 CT IGOR I SIKORSKY MEMORIAL AIRPORT WBAN 73 CT GUILFORD COOP 73 NY ORIENT POINT STATE PARK COOP 72 NY BRIDGEHAMPTON COOP 71 CT DANBURY COOP 70 NY WESTHAMPTON GABRESKI AP WBAN 70

We have seen a nice improvement since last fall as it’s tough to keep a really dry pattern going in this much wetter climate.

Top 5 warmth across the area for the 1st week of May. EWR…5th warmest LGA….5th HPN….5th JFK….5th ISP…..4th BDR….5th PHI…..5th

Unfortunately, the Pacific Jet has been too strong during the winter. So as the gradient weakens further into the spring, the weaker jet isn’t able to act as a kicker. So these closed lows get stuck in place when people are ready for sunny spring weather. But the good news is that the northern edge of the drought areas to the north of I-80 and into CT has improved with the soaking rains there in recent days.

It may turn out to be another case of the record WPAC warm pool driving the La Niña background more than what is occurring in the traditional ENSO regions east of the Dateline.

Very impressive omega blocking pattern this month.