bluewave

2010 to 2018 wasn’t natural variability since the reason the snow increased was due to the warmer atmosphere holding more moisture while the storm tracks remained cold.

That Midwest warmth in March 2012 was more historic than the cold in 2015 was. The few months with -10 or more departures the CONUS since 2015 have been few and far between compared to the months over +10. This is a CONUS wide phenomenon and not just limited to one region. You can see how getting a +10 month nearly every winter since the 2015 higher temperature reset has become the norm while extreme cold is very isolated to places like Montana. Plus our Arctic outbreaks have shrunk the geographic footprint. So an Arctic outbreak into the Plains doesn’t extend all the way to the coast like it did as recently as the 1990s. Dec…2015….NYC….+13.3 JAN…2017….BTV…..+11.0 FEB….2017….ORD….+10.3 FEB…..2018…ATL….+10.6 FEB….2019…MGM….+10.5 JAN….2020…YAM….+9.8 DEC….2021….DFW….+13.2 JAN….2023….DXR….+12.3 FEB….2023…..SSI…..+9.8 DEC….2023….INL…..+15.8 FEB…..2024….FAR…..+17.5 DEC….2024…..LND…..+11.3

Could be the best Noreaster of 2025 this week. While the Euro may be overdone on the intensity, the gradient should be tight enough for easterly gusts over 40 and very rough surf and wind driven heavy rain potential. It’s possible that with the low clouds and easterly flow, that some spots may not get out of the 40s for afternoon highs. This is impressive cold for late May when the average daily high is 73°.

During transition periods from cold to warm like 2010 to 2018 ,we got amazing snows due to the way the pattern was shifting. First, the warming process loaded the atmosphere with more moisture. Second, the colder storm tracks to the south of the big cities had already been in place from 09-10, 10-11, 13-14, and 14-15. But the signs that this was getting ready to change were evident with the pattern during December to March 2011-2012. March near the Great Lakes was one of the most anomalously warm months there since the 1800s with +15° degree warm departures. The warmth continued into January 2013 and we had the Southeast Ridge briefly linking up with the -AO in December. Nemo in February was one of the greatest phasing blizzards with 50dBZ returns from snow which was a first for the Doppler radars which were installed back in the 1990s. Then it was winter cold and snow galore through March 2015. Then in December 2015 the Northeast experienced one of the most anomalously warm months warm winter months ever going over +13. But the lingering cold storm track in January resulted in the greatest snowstorm near 30” around NYC. 2016-2017 followed as one of the warmest winters on record but there were blizzards after days in the 60s with record warmth. Then 17-18 featured our greatest 14 days of cold and snow this century from after Christmas into early January with the amazing benchmark 950mb blizzard. Fast forward to February for our first 80° winter heat before the record snowy February. This continued into November 2018 with the record snowstorm. But the storm track became very warm that 2018-2019 winter with one cutter after another and nearly no snow during DJF. Since that 18-19 that warmer storm shift and much faster Pacific Jet, we have been getting more consistent record warmth a lower snowfall. So we were getting more extended warmth like 22-23 to 23-24 plus the very warm Northern Stream of the Pacific Jet. So the cold storm tracks have been absent even this past winter when we had average to slightly below average cold. It was still 41° with a strong Southeast Ridge in NYC on the days with .25 or more of precipitation. So the warmer storm tracks muted the influence of the cold and snowfall was well below average again. So the winter warming with first began to emerge in 11-12 has become more widespread. Then the warmer storm tracks with started in 18-19 have become more frequent. So when those 2 features become dominant it loads the dice for below normal to well below normal snow into the 2020s. it would be nice if we could get at least get a brief return to colder storm tracks and better snows during the 2nd half of the 2020s. But the climate has already significantly warmed. The strength of the Pacific Jet hasn’t allowed benchmark colder storm tracks during the winter. Instead, it has been all cutters, huggers and suppressed Southern Stream storm tracks. But most on here would be happy with a 16-17 repeat with record warmth and a few nice blizzards.

They have run the climate models pretty far out in time. The summer forecast through later in the century is for drier to our west and wet for our area. Plus an extensive ridge across North America allowing the Western Ridge to link up with the WAR . We have seen this pattern at times over the last decade like in June 2021 and other months. Though the trough which has been over the Ohio Valley between the WAR and Western Ridge has been stronger than what is indicated in the long range forecast. So it could eventually weaken in coming decades with the expansion of drought into the Plains. We see how it goes.

Yeah, areas further south will naturally see the declines in snowfall first since they were always more marginal to begin with. The further north lake effect zones and higher elevations of the Northeast will still do well since warmer storm tracks for the coast are good for snowfall in those areas. While we can’t completely rule out some major volcanic event which could temporarily cool the climate, those type of events have been pretty rare and aren’t easily predictable.

Newark isn’t the warmest location in NJ since the ASOS is right on the bay and is subject to cooling sea breezes. Several other locations in NJ have had more 90° days since the flow turned more onshore in recent years. There are 4 stations in NJ with more 90° days than Newark over the last 10 years. These sea breezes are why the areas east of the Hudson River in New York don’t have as many 90° days as NJ does. Data for January 1, 2015 through December 31, 2024 Click column heading to sort ascending, click again to sort descending. HIGHTSTOWN 2 W COOP 383 HARRISON COOP 376 FREEHOLD-MARLBORO COOP 351 CANOE BROOK COOP 348 NEWARK LIBERTY INTL AP WBAN 343 Newark Area ThreadEx 343 TETERBORO AIRPORT WBAN 310 ESTELL MANOR COOP 307 New Brunswick Area ThreadEx 304 NEW BRUNSWICK 3 SE COOP 304 Several other stations in NJ had an average high within a degree of Newark during the summer of 1993. Data for June 1, 1993 through August 31, 1993 Click column heading to sort ascending, click again to sort descending. WAYNE COOP 90.1 NEWARK LIBERTY INTL AP WBAN 88.9 Newark Area ThreadEx 88.9 MOORESTOWN 4 E COOP 88.1 LITTLE FALLS COOP 88.0 WOODSTOWN PITTSGROV 4E COOP 88.0

This wasn’t the case for many first order sites such as NYC. So recent snowfall measurements are inflated relative to the way snowfall was measured prior to the 1990s around NYC and to before 1950 in other locations. So boost pre-1950 snowfall totals by 15-20% and the majority of first order sites in the U.S. will show a steady decline since the late 1800s. Several stations already show a long term snowfall decline. So imagine how much steeper a decline we would have if the snowfall was measured as frequently as it is today. Plus places like NYC would use melted down gauge snow equivalents and not actual measurements like in the blizzard of 1888 using a simple 10:1 ratio which is very inaccurate when the 1800s were so cold with much higher ratios. https://news.ucar.edu/14009/snowfall-measurement-flaky-history As a hydrometeorological instructor in UCAR’s COMET program and a weather observer for the National Weather Service, I am keenly interested in weather trends. In this case, climate change is an important factor to explore, since we know that the heaviest precipitation events have intensified in many parts of the world (see related story: Torrents and droughts and twisters - oh my!). But when we turn to snowstorms in the Northeast, or elsewhere in the U.S., there is an additional factor at work when comparing modern numbers with historical ones. Quite simply, our measuring techniques have changed, and we are not necessarily comparing apples to apples. In fact, the apparent trend toward bigger snowfalls is at least partially the result of new—and more accurate—ways of measuring snowfall totals. Climate studies carefully select a subset of stations with consistent snow records, or avoid the snowfall variable altogether. Official measurement of snowfall these days uses a flat, usually white, surface called a snowboard (which pre-dates the popular winter sport equipment of the same name). The snowboard depth measurement is done ideally every 6 hours, but not more frequently, and the snow is cleared after each measurement. At the end of the snowfall, all of the measurements are added up for the storm total. NOAA’s cooperative climate observers and thousands of volunteers with the Community Collaborative Rain, Hail and Snow (CoCoRaHS), a nationwide observer network, are trained in this method. This practice first became standard at airports starting in the 1950s, but later at other official climate reporting sites, such as Manhattan’s Central Park, where 6-hourly measurements did not become routine until the 1990s. Earlier in our weather history, the standard practice was to record snowfall amounts less frequently, such as every 12 or 24 hours, or even to take just one measurement of depth on the ground at the end of the storm. You might think that one or two measurements per day should add up to pretty much the same as measurements taken every 6 hours during the storm. It’s a logical assumption, but you would be mistaken. Snow on the ground gets compacted as additional snow falls. Therefore, multiple measurements during a storm typically result in a higher total than if snowfall is derived from just one or two measurements per day. That can make quite a significant difference. It turns out that it’s not uncommon for the snow on the ground at the end of a storm to be 15 to 20 percent less than the total that would be derived from multiple snowboard measurements. As the cooperative climate observer for Boulder, Colorado, I examined the 15 biggest snowfalls of the last two decades, all measured at the NOAA campus in Boulder. The sum of the snowboard measurements averaged 17 percent greater than the maximum depth on the ground at the end of the storm. For a 20-inch snowfall, that would be a boost of 3.4 inches—enough to dethrone many close rivals on the top-10 snowstorm list that were not necessarily lesser storms! Another common practice at the cooperative observing stations prior to 1950 did not involve measuring snow at all, but instead took the liquid derived from the snow and applied a 10:1 ratio (every inch of liquid equals ten inches of snow). This is no longer the official practice and has become increasingly less common since 1950. But it too introduces a potential low bias in historic snowfalls because in most parts of the country (and in the recent blizzard in the Northeast) one inch of liquid produces more than 10 inches of snow. This means that many of the storms from the 1980s or earlier would probably appear in the record as bigger storms if the observers had used the currently accepted methodology. Now, for those of you northeasterners with aching backs from shoveling, I am not saying that your recent storm wasn’t big in places like Boston, Portland, or Long Island. But I am saying that some of the past greats—the February Blizzard of 1978, the Knickerbocker storm of January 1922, and the great Blizzard of March 1888—are probably underestimated. So keep in mind when viewing those lists of snowy greats: the older ones are not directly comparable with those in recent decades. It’s not as bad as comparing apples to oranges, but it may be like comparing apples to crabapples. Going forward, we can look for increasingly accurate snow totals. Researchers at NCAR and other organizations are studying new approaches for measuring snow more accurately (see related story: Snowfall, inch by inch). But we can’t apply those techniques to the past. For now, all we can say is that snowfall measurements taken more than about 20 or 30 years ago may be unsuitable for detecting trends – and perhaps snowfall records from the past should not be melting away quite as quickly as it appears. Update • January 29, 2015 | Thanks to thoughtful feedback by several colleagues, this article has been updated. Paragraph 3 now includes a description of how climate studies handle the data inconsistencies. Paragraph 9 was added to describe the pre-1950s practice, no longer in wide use, of recording liquid water content only, and not snow depth. Matt Kelsch is a hydrometeorologist in UCAR's COMET Program. He specializes in weather and climate events involving water, such as floods, droughts, rain, hail, or snow. Kelsch develops and delivers educational materials designed for both domestic and international groups including National Weather Service forecasters, the military, the World Meteorological Organization, university students and faculty, government agencies, and private industry.

Some of the models show the severe drought shifting eastward into the Plains from the 2030s into the 2050s. But it would require the ridge east of New England shifting for us to get westerly winds from the Plains. I suppose a compromise could be possible with both ridges linking up and alternating westerly and southerly flow. But this hasn’t been the case in the last decade with more of a trough over the Great Lakes and Ohio Valley and inshore flow. Notice how these days the common summer pattern has been a ridge east of New England and over the West. But from 2010 to 2013 when we had all the 100° heat and westerly flow there was a ridge in the Plains.

Wayne, NJ to the west of Newark actually had a higher average maximum temperature than Newark did with more 90° days. So the heat wasn’t just localized to Newark. But Newark did lead with the 95° days though a few COOPs nearby were close. A local COOP had a higher max at 106° while Newark only made it to 105° that summer. Data for June 1, 1993 through August 31, 1993 Click column heading to sort ascending, click again to sort descending. WAYNE COOP 90.1 Newark Area ThreadEx 88.9 NEWARK LIBERTY INTL AP WBAN 88.9 MOORESTOWN 4 E COOP 88.1 WOODSTOWN PITTSGROV 4E COOP 88.0 LITTLE FALLS COOP 88.0 INDIAN MILLS 2 W COOP 87.1 LAMBERTVILLE COOP 87.1 PEMBERTON COOP 87.0 BELLEPLAIN STA FOREST COOP 86.9 CRANFORD COOP 86.9 PENNSAUKEN 1N COOP 86.7 LODI COOP 86.7 1993 #90° days in NJ Data for January 1, 1993 through December 31, 1993 Click column heading to sort ascending, click again to sort descending. WAYNE COOP 68 Newark Area ThreadEx 49 NEWARK LIBERTY INTL AP WBAN 49 WOODSTOWN PITTSGROV 4E COOP 45 MOORESTOWN 4 E COOP 44 LAMBERTVILLE COOP 41 TOMS RIVER COOP 40 95° days in NJ Data for January 1, 1993 through December 31, 1993 Click column heading to sort ascending, click again to sort descending. Newark Area ThreadEx 25 NEWARK LIBERTY INTL AP WBAN 25 WAYNE COOP 22 TOMS RIVER COOP 18 WOODSTOWN PITTSGROV 4E COOP 16 Maxumum NJ temoersrure in 1993 Data for January 1, 1993 through December 31, 1993 Click column heading to sort ascending, click again to sort descending. PENNSAUKEN 1N COOP 106 NEWARK LIBERTY INTL AP WBAN 105 Newark Area ThreadEx 105 TUCKERTON 2 NE COOP 104 TOMS RIVER COOP 104 WAYNE COOP 104

The wild card will be what happens to rainfall to our west. Some of long range models shift the Western Drought into the Plains in the coming years and decades. This could potentially alter the more onshore flow we have been experiencing over the last decade. So in that case we would regularly see 10 or more days reaching 100° over NJ and 5+ on Long Island. But it would require the ridge east of New England shifting to our West. This is highly speculative since the current pattern we are experiencing has been different from that scenario. No matter how much the climate warms, we aren’t going to see many 100° days with onshore flow dominating.

Yeah, this is why other studies and the recent acceleration of warming are pointing toward higher climate sensitivity than previously believed. The 1.5C limit was always an unrealistic target for how fast we continue to burn fossil fuels. Unless something happens to slow this trajectory, we will be well on the way to +3C to +5C of warming. https://cpo.noaa.gov/scientists-find-cloud-feedbacks-amplify-warming-more-than-previously-thought/ Clouds play an important role in how much the Earth warms when greenhouse gases like carbon dioxide increase. However, scientists have struggled to determine whether low-level clouds in the tropics slow down or speed up global warming, creating uncertainty in climate predictions. A new study published in Nature Communications and funded by the Climate Program Office’s Modeling, Analysis, Predictions, and Projections (MAPP) program adds to the growing evidence that cloud feedback is very likely to amplify warming in the climate system, rather than reduce it. The study found that the impact of clouds in the tropical Pacific and Atlantic Oceans, two areas where low clouds are especially important, is much stronger than scientists previously thought — 71% higher. It also ruled out the possibility that tropical low clouds could have a cooling effect to offset warming. These findings narrow the uncertainty around one of the biggest unknowns in climate science and enable more accurate predictions of how much warming we might expect. This work was possible thanks to new techniques that balanced conflicting data from different regions, giving clearer answers. The results show that Earth’s climate is likely more sensitive to rising carbon dioxide levels than many models have suggested. A stronger positive cloud feedback means faster and higher levels of warming. It also highlights the need to improve how climate models represent clouds, especially in tropical areas, to prepare better for the challenges of a changing climate. The investigators will extend the value of this study by developing and delivering a piece of software to NOAA that will diagnose issues with low cloud feedback in new versions of NOAA’s modeling systems. This will lead to improvements in NOAA models’ ability to capture appropriate levels of cloud feedback, and improvements in processes that lead to weather and climate prediction skill. In the early 2000s, climate scientists could not say with confidence whether clouds would mitigate or amplify climate change. Some hypothesized that clouds might work to oppose a significant portion of human-caused warming by reflecting more incoming solar energy back out to space, while others hypothesized that particular changes in clouds might magnify warming by trapping more energy in the atmosphere. In 2001, NOAA’s Geophysical Fluid Dynamics climate model was one of only three that simulated the type of significant positive cloud feedback we now know is likely happening. The MAPP and Climate Variability & Predictability (CVP) programs are advancing cloud representation in climate models through ongoing funded projects. By studying tropical cloud processes and precipitation and improving how they are represented across scales, these efforts are strengthening predictions and providing a clearer picture of our climate future. Read the study »

It’s going to be a challenge for places like Newark to ever see 20 consecutive 90° days again with how wet the climate has become with increased summer onshore flow. Number of Consecutive Days Max Temperature >= 90 for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Last value also occurred in one or more previous years. Period of record: 1931-01-01 to 2025-05-14 1 20 1988-07-29 through 1988-08-17 2 14 2010-07-16 through 2010-07-29 3 12 1995-07-24 through 1995-08-04 - 12 1972-07-14 through 1972-07-25 4 11 2012-06-28 through 2012-07-08 - 11 1973-08-26 through 1973-09-05 - 11 1953-08-24 through 1953-09-03 5 10 2022-08-02 through 2022-08-11 - 10 2006-07-27 through 2006-08-05 - 10 2002-08-10 through 2002-08-19 Data for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. 1988-07-29 95 0.00 1988-07-30 99 0.00 1988-07-31 90 T 1988-08-01 91 0.00 1988-08-02 94 0.00 1988-08-03 93 0.00 1988-08-04 92 0.00 1988-08-05 90 T 1988-08-06 90 0.00 1988-08-07 93 T 1988-08-08 90 0.00 1988-08-09 92 0.00 1988-08-10 93 0.01 1988-08-11 97 0.00 1988-08-12 95 0.00 1988-08-13 98 0.00 1988-08-14 98 0.00 1988-08-15 99 0.00 1988-08-16 92 0.00 1988-08-17 90 0.05

Back in the drier climate era days we would often go more than 4 days with no rain. This is why the longest heatwaves occurred in those days. But late May has especially seen more blocking and cutoffs last 10 years or so. This makes it prime time for cutoff lows and frequent rainy intervals. It’s the primary reason we still haven’t seen widespread 100° heat this time of year yet. In a drier climate with less blocking the May 1996 record heat would have easily been surpassed. Monthly Data for May 1996 for Upton NY NWS CWA Click column heading to sort ascending, click again to sort descending. NJ NEWARK LIBERTY INTL AP WBAN 99 NY MINEOLA 1 NE COOP 99 NY OCEANSIDE COOP 98 NY ISLIP-LI MACARTHUR AP WBAN 98 CT NORWICH PUBLIC UTILITY PLANT COOP 98 NJ PLAINFIELD COOP 97 NY LAGUARDIA AIRPORT WBAN 97 NY DOBBS FERRY-ARDSLEY COOP 97 NY MINEOLA COOP 97 CT STAMFORD 5 N COOP 97 CT IGOR I SIKORSKY MEMORIAL AIRPORT WBAN 97 NY PATCHOGUE 2 N COOP 97 NY PORT JERVIS COOP 96 NJ CRANFORD COOP 96 NJ JERSEY CITY COOP 96 NY NY CITY CENTRAL PARK WBAN 96 NJ HARRISON COOP 96 NJ TETERBORO AIRPORT WBAN 96

When I mentioned to Philly to Boston I was highlighting coastal areas closer to the I-95 corridor. These areas are naturally seeing a decline in snowfall first. Higher elevations in the interior Northeast have more leeway since they can still do well with a warmer more northward shifted storm track.

Go back to around 2013 and you will see that most years have at least some measurable rainfall on at least one of the Friday to Monday extended Memorial Day weekend days.

I don’t do extended snowfall forecasts for your area north of Boston. My statement on the declining snowfall is based on the region around NYC. But if you run the snowfall data back to the late 1800s, it shows a steady decline with ups and downs along the way. Plus if they measured snowfall the same way as they did before the 1990s, it would show higher totals prior to that and a steeper decline. Since snowfall in the old days was under measured by 15-20% due to less frequent measurements. NYC is moving into an era when the seasonal average snowfall will dip under 20” on a long term basis once we get into the coming decades. The last 7 years are a preview of the future. But we could see a bounce off the bottom of recent years before resuming the decline in the 2030s.

Hopefully, the cutoff for the extended Memorial Day weekend is more frontloaded to Friday into Saturday and moves to our NE on Monday.

Since this -PDO cycle only started in 2019 after the 4 to 5 year +PDO and super El Niño, not sure how you can make that statement after only about 7 years. But I suppose you could make the argument that in a new regime of shorter PDO cycling since 1999, a warming WPAC could load the dice for the -PDO phases lasting longer than the +PDO phases. Still have to wait and see if the recent Nino 1+2 warming isn’t the beginning of a shift back to more +PDO in a few years. But with all the warming since the 2014-2015 to 2017-2018 +PDO period, my guess is that it would be a warmer and less snowy version of those years.

My guess is that the Aleutian Ridge setting multiyear records since 2019 on an annual basis is a combination of factors with the warming from the earlier -PDO eras being an important factor. Sure the location has its origins in the PDO. But the magnitude and the SST warming underneath is a result of the rapidly warming oceans and rising 500mb heights. You can see how many magnitudes of order stronger this ridge is from the cold 1950 to 1976 -PDO era.

I was saying that the snowfall would be below normal again as early as last December when the Pacific Jet began beating guidance beyond 120 hrs out. We used to get KU snowstorms in the old days when the AO blocks were centered over the North Pole. But it doesn’t matter where the block is these days as it usually finds a way to link up with the Southeast Ridge. I also doubted those long range snowfall forecast last February as I was thinking the ridge would push the best snowfall axis’s further north which was what happened.

We shifted to an all or nothing snowfall pattern since the 1990s with all the average to above average snowfall seasons featuring KU Benchmark storm tracks. During the 1960s to early 1990s it was cold enough to get closer to average snowfall with a bunch of smaller to moderate events and no KUs. Moderate snowfall seasons closer to average were the norm of that colder 30 year period. Very few well below or well above average snowfall seasons. So having to rely exclusively on KU events over the last 30 years has lead to more well below normal seasons since 2018-2019 when the Pacific Jet has been so overpowering preventing benchmark dominant storm tracks. Having a 50-100 year concentration of benchmark tracks from 2010 to 2018 with so many record seasons masked this longer term trend since the 1990s. Once this anomalous pattern shifted, we were left with the well below normal background snowfall pattern with the exception of 20-21 around NYC and January 22 from Long Island into Eastern New England.

It was a very short-lived heatwave around NYC in 1936 as the overall summer wasn’t warm by modern standards.

It was much colder back in those days so the hugger tracks were often 3-6” instead of the 1-3” which have become the norm since 2019. There were also clippers with 3-6” and 4-8” snows which were common which dropped south of NYC. These days the clippers have become cutters due to the stronger Southeast Ridge pushing the storm track further north. Plus there were non KU Benchmark tracks at times with similar amounts. So there was a wider variety of ways to get near 20” or more since the storm tracks were much colder.

Recent studies have found that if the natural Grasslands weren’t removed, then there wouldn’t have been a Dust Bowl. But a typical drier pattern that has occurred over intervals of time in the past. None of the previous drought patterns produced that type of heat.The record heat was a function of the desertification brought on by the the land use practices during that era. https://www.pnas.org/doi/10.1073/pnas.0810200106 Abstract The “Dust Bowl” drought of the 1930s was highly unusual for North America, deviating from the typical pattern forced by “La Nina” with the maximum drying in the central and northern Plains, warm temperature anomalies across almost the entire continent, and widespread dust storms. General circulation models (GCMs), forced by sea surface temperatures (SSTs) from the 1930s, produce a drought, but one that is centered in southwestern North America and without the warming centered in the middle of the continent. Here, we show that the inclusion of forcing from human land degradation during the period, in addition to the anomalous SSTs, is necessary to reproduce the anomalous features of the Dust Bowl drought. The degradation over the Great Plains is represented in the GCM as a reduction in vegetation cover and the addition of a soil dust aerosol source, both consequences of crop failure. As a result of land surface feedbacks, the simulation of the drought is much improved when the new dust aerosol and vegetation boundary conditions are included. Vegetation reductions explain the high temperature anomaly over the northern U.S., and the dust aerosols intensify the drought and move it northward of the purely ocean-forced drought pattern. When both factors are included in the model simulations, the precipitation and temperature anomalies are of similar magnitude and in a similar location compared with the observations. Human-induced land degradation is likely to have not only contributed to the dust storms of the 1930s but also amplified the drought, and these together turned a modest SST-forced drought into one of the worst environmental disasters the U.S. has experienced.