bluewave

The Euro has a first for this weekend. Newark has never had two days in May with a high in the 50s following a 96° or higher reading. So a continuation of our weather extremes pattern which has become prominent since 2010. Time Series Summary for NEWARK LIBERTY INTL AP, NJ - Month of May Click column heading to sort ascending, click again to sort descending. Rank Year Highest Max Temperature Following Lowest Max 1 1996 99 61 2 1992 98 63 - 1987 98 96 - 1962 98 67 3 1965 97 69 4 2021 96 ? - 2016 96 83 - 1969 96 85 - 1964 96 68

Wantagh gusting to 39 mph. From W at 22 mph Gusting to 39 mph

Hail showing up on radar in Oceanside and Rockville Centre.

Newark taking the lead on the early season heat since the weekend. High of 94 after reaching 96 on Saturday. Last few years it was usually LGA in the lead for these warm ups. CLIMATE REPORT NATIONAL WEATHER SERVICE NEW YORK, NY 433 PM EDT WED MAY 26 2021 ................................... ...THE NEWARK NJ CLIMATE SUMMARY FOR MAY 26 2021... VALID TODAY AS OF 0400 PM LOCAL TIME. CLIMATE NORMAL PERIOD 1991 TO 2020 CLIMATE RECORD PERIOD 1893 TO 2021 WEATHER ITEM OBSERVED TIME RECORD YEAR NORMAL DEPARTURE LAST VALUE (LST) VALUE VALUE FROM YEAR NORMAL ................................................................... TEMPERATURE (F) TODAY MAXIMUM 94 259 PM 96 1965 75 19 77 MINIMUM 66 500 AM 44 1967 57 9 58 AVERAGE 80 66 14 68

Yeah, filtered sunshine through the marine layer here in SW Suffolk.

I wonder if Newark ever had a Memorial Day weekend when one of the daily high temperatures was colder than Christmas? Data for December 25 - NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Date Max Temperature Min Temperature Precipitation Snowfall Snow Depth 1964-12-25 69 44 0.01 0.0 0 1982-12-25 68 40 0.02 0.0 0 2014-12-25 64 41 0.10 0.0 0 2015-12-25 63 54 0.03 0.0 0 2020-12-25 62 28 0.66 0.0 0

The NAM didn’t get the memo that this is supposed to be the Memorial Day weekend.

Clearing out at Newark now. Newark Liberty PTSUNNY 77 65 66 SW12 30.05F

This May ranks up there for extreme temperature volatility. Cool start to the month followed by record warmth last weekend. More 90s away from the ocean today followed by an unusually cool Memorial Day weekend. So a continuation of the extreme wavelength swings following the record AO reversal back in February.

Yeah, it looks like our best rainfall potential in a while. Models now have high temperatures struggling to get much above 60°on Saturday with a chilly NE flow. Very unusual for highs in the mid or upper 90s around May 20th to fall to near 60 at the end of May. It only has happened in 2017 and 1996 at Newark. 2017-05-17 92 59 2017-05-18 94 74 2017-05-19 93 66 2017-05-20 66 53 2017-05-21 66 51 2017-05-22 60 55 2017-05-23 70 56 2017-05-24 70 57 2017-05-25 59 56 2017-05-26 76 55 2017-05-27 74 58 2017-05-28 71 58 2017-05-29 61 57 2017-05-30 59 55 2017-05-31 80 58 1996-05-19 93 54 1996-05-20 99 72 1996-05-21 96 70 1996-05-22 82 63 1996-05-23 84 57 1996-05-24 80 59 1996-05-25 76 53 1996-05-26 66 56 1996-05-27 64 52 1996-05-28 61 55 1996-05-29 64 55 1996-05-30 70 50 1996-05-31 80 49

The Euro and CMC have the bulk of the rain Friday into Friday night. Maybe a few lingering showers into Saturday. But a cool NE flow looks likely into the afternoon. So Saturday may feature highs only in the upper 50s to low 60s around NYC depending on cloud cover. This would put it near the coolest maxes that we have seen this late in the season since 2015. It could be in excess of 30° colder than the mid 90s last Saturday. Newark low maxes recent years bolded 5/29 60 in 1950 60 in 1940 61 in 2017+ 5/30 53 in 1953 59 in 2017 64 in 2000+ 5/31 61 in 1953 63 in 1992 63 in 1984 6/1 58 in 1945 61 in 2015 63 in 1964 6/2 54 in 1946 57 in 2015 60 in 1945+ 6/3 53 in 1945 62 in 1996 63 in 1997 6/4 53 in 1945 58 in 2003 60 in 1941 6/5 58 in 1945 60 in 1941 61 in 2009 6/6 60 in 2017 61 in 2004 61 in 2000+

That site is part of the original mesonet that was installed several years back. It’s located at 311 feet so it’s one of the coolest NYC sites on hot days.Temperatures can fall off pretty quickly above the standard 2m height. That’s why I am not a fan of rooftop temperatures. A ground station like Wantagh today is 1.5° cooler at 9m than 2m. http://www.nysmesonet.org/weather#network=nysm&stid=manh Elevation: 311 feet

The new ground level stations look interesting. Not a big fan of the rooftop station temperatures. I posted the high temperature summary from Saturday. http://nysmesonet.org/networks/nyc Ten sites are located at ground level, eleven sites are deployed on roof tops, and one site is located on a pier. A majority of Micronet stations measure air temperature, relative humidity, precipitation, and pressure. A mix of stations also measure wind speed and direction, solar radiation, snow depth, soil temperature and moisture, surface (skin) temperature, and water temperature. Micronet data are collected every 5 minutes, quality controlled, archived and made available to users in real-time. The 17 Con Edison sites and 5 NYS Mesonet sites located in NYC are shown in the data display below. Station Max Min Avg Max Min Max Min Liquid Peak Gust Peak 5m Avg Integrated 13th St./16th / Alphabet City 93 67 80 93 67 66 28 0.00 13 4:10pm 4 2:20pm 17.0 160 Ave. / Howard Beach 91 61 77 91 61 87 29 0.00 28th St. / Chelsea 90 66 79 90 66 73 29 0.00 19 2:40pm 6 2:40pm 15.3 Astoria 91 64 78 91 64 77 29 0.00 17 4:40pm 9 2:05pm 17.7 Bensonhurst / Mapleton 92 65 79 92 65 73 28 0.00 15.7 Bronx Mesonet 88 64 77 88 64 73 34 0.00 23 3:00pm 13 3:00pm 19.8 Brooklyn Mesonet 88 63 77 88 63 74 31 0.00 28 2:40pm 18 2:40pm 18.3 Brownsville 94 64 79 94 64 76 26 0.00 Corona 92 65 79 92 65 73 27 0.00 E 40th St. / Murray Hill 90 67 79 90 67 64 30 0.00 Fresh Kills 91 64 79 91 64 66 30 0.00 20 6:00pm 11 5:40pm Glendale / Maspeth 90 64 79 90 64 75 29 0.00 Gold Street / Navy Yard 90 68 80 90 68 60 29 0.00 22 3:00pm 12 3:00pm 18.2 Lefferts / South Ozone Park 93 62 78 93 62 83 28 0.00 Manhattan Mesonet 87 70 80 87 70 60 32 0.00 30 2:35pm 17 2:30pm 15.7 Newtown / Long Island City 90 66 79 90 66 66 27 0.00 18 5:15pm 7 2:40pm 16.9 Queens Mesonet 88 63 77 88 63 76 32 0.00 23 3:00pm 15 4:50pm 18.0 Queensbridge / Dutch Kills 91 67 80 91 67 68 27 0.00 15.2 Staten Island Mesonet 89 65 78 89 65 63 32 0.00 28 6:00pm 16 2:45pm 18.1 TLC Center 89 66 78 89 66 67 30 0.00 19 3:05pm 8 2:40pm 17.8 Tremont / Van Nest 93 64 79 93 64 75 28 0.00 16 2:25pm 5 3:05pm 17.7

The Euro has low 90s temperatures with low 70s dew points on Wednesday. So the heat indices will soar well into the 90s away from the shore where there will be a strong sea breeze. Hopefully, the convection holds together down to the coast for some much needed rainfall in the evening.

Memorial Day may end up being the best day of the entire holiday weekend.

It would be interesting to see how many more 100° days we would have had without the big increase in agriculture in those areas. https://www.sciencemag.org/news/2018/02/america-s-corn-belt-making-its-own-weather The United States’s Corn Belt is making its own weather By Kimberly HickokFeb. 16, 2018 , 12:05 PM The Great Plains of the central United States—the Corn Belt—is one of the most fertile regions on Earth, producing more than 10 billion bushels of corn each year. It’s also home to some mysterious weather: Whereas the rest of the world has warmed, the region’s summer temperatures have dropped as much as a full degree Celsius, and rainfall has increased up to 35%, the largest spike anywhere in the world. The culprit, according to a new study, isn’t greenhouse gas emissions or sea surface temperature—it’s the corn itself. This is the first time anyone has examined regional climate change in the central United States by directly comparing the influence of greenhouse gas emissions to agriculture, says Nathan Mueller, an earth systems scientist at the University of California (UC), Irvine, who was not involved with this study. It’s important to understand how agricultural activity can have “surprisingly strong” impacts on climate change, he says. The Corn Belt stretches from the panhandle of Texas up to North Dakota and east to Ohio. The amount of corn harvested in this region annually has increased by 400% since 1950, from 2 billion to 10 billion bushels. Iowa leads the country for the most corn produced per state. Get more great content like this delivered right to you!To see whether this increase in crops has influenced the region’s unusual weather, researchers at the Massachusetts Institute of Technology in Cambridge used computers to model five different 30-year climate simulations, based on data from 1982 to 2011. First, they compared simulations with high levels of intense agriculture to control simulations with no agricultural influence. Unlike the real-life climate changes, the control simulations showed no change in temperature or rainfall. But 62% of the simulations with intense agriculture resulted in temperature and rainfall changes that mirror the observed changes, the team reports this week in Geophysical Research Letters. Map of the central United States, showing changes in rainfall during the last third of the 20th century. Areas of increased rainfall are shown in green, with darker colors representing a greater increase. MASSACHUSETTS INSTITUTE OF TECHNOLOGY The team then compared its results to historical global simulations from the World Climate Research Programme (WCRP), an international program for the coordination of global climate research sponsored by the International Council for Science, the World Meteorological Organization, and the Intergovernmental Oceanographic Commission of UNESCO. WCRP’s models take into account greenhouse gas emissions and other natural and humanmade influences, but do not consider agricultural land use. When researchers ran the numbers for the Corn Belt, the global models fell short of reality: They predicted both temperature and humidity to increase slightly, and rainfall to increase by up to 4%—none of which matches the observed changes. Other climate simulations that use sea surface temperature variation didn’t match observed changes, either. Those simulations matched historical data until 1970; after that, the simulations predicted temperatures to keep increasing, rather than decreasing as they did in reality. This is a strong indication that agriculture, and not changing sea surface temperature, caused the regional changes in climate during the last third of the 20th century, the researchers say. “The [influence] of agriculture intensification is really an independent problem from greenhouse gas emissions,” says Ross Alter, lead author of the study and now a meteorologist with the U.S. Army Corps of Engineers in Hanover, New Hampshire. In fact, Alter says, heavy agriculture likely counteracted rising temperatures regionally that might have otherwise resulted from increasing greenhouse gas emissions. One other place that shows a similar drop in temperatures, he notes, is eastern China, where intensive agriculture is widespread. But how does agriculture cause increased rainfall and decreased temperatures? The team suspects it has to do with photosynthesis, which leads to more water vapor in the air. When a plant’s pores, called stomata, open to allow carbon dioxide to enter, they simultaneously allow water to escape. This increases the amount of water going into the atmosphere and returning as rainfall. The cycle may continue as that rainwater eventually moves back into the atmosphere and causes more rainfall downwind from the original agricultural area. Rong Fu, a climate scientist at UC Los Angeles, agrees with the team’s assessment. She also thinks that though human influence might be “greater than we realize,” this regional climate change is probably caused by many factors, including increased irrigation in the region. “This squares with a lot of other evidence,” says Peter Huybers, a climate scientist at Harvard University, who calls the new study convincing. But he warns that such benefits may not last if greenhouse gas emissions eventually overpower the mitigating effect of agriculture. Alter agrees, and says it’s unlikely that the large increases in U.S. crop production during the 20th century will continue. Other scientists have voiced concern that agricultural production could soon be reaching its limit in many parts of the world. “Food production is arguably what we’re more concerned about with climate change,” Mueller says. And understanding how agriculture and climate will continue to affect one another is crucial for developing projections for both climate and agricultural yields. “It’s not just greenhouse gasses that we need to be thinking about.”

The bulk of the rain on the 12z Euro is Friday into Friday night. Some lingering showers on Saturday. But the weekend looks cool with plenty of easterly flow. This past weekend when we reached the mid 90s will turn out to have been the best beach weekend of May.

Central Park is a great place for weather observations provided that the ASOS is placed in an open area away from trees. The problem with the Central Park site is that it was no longer maintained after the early 90s. Since the early 90s, is has been tucked in the deep shade under the trees. So the lack of direct sunlight results in afternoon highs that are 2° to 3° cooler than they used to be prior to the 90s. So this created a break in continuity from earlier observations. As for the airports, the ASOS units are placed on grassy surfaces. While there is plenty of concrete at the airports, there really isn’t any more or less than the surrounding neighborhoods where the people live. But since the airports are located on the water, they are prone to sea breezes. So there are neighborhoods around NYC metro that can be hotter depending on wind direction. Central Park before the sensor was blocked by trees Most recent photo as of 2013 under trees and violating the ASOS handbook sitting rules

The higher scoring Euro and CMC are dry for the Memorial Day weekend. They bring in the rain for Friday and Friday night. But it looks like a cool Sat to Mon with plenty of easterly flow. The big high east of New England is back again as we start June.

https://www.washington.edu/news/2020/12/15/a-i-model-shows-promise-to-generate-faster-more-accurate-weather-forecasts/ December 15, 2020 A.I. model shows promise to generate faster, more accurate weather forecasts Hannah Hickey UW News Today’s weather forecasts come from some of the most powerful computers on Earth. The huge machines churn through millions of calculations to solve equations to predict temperature, wind, rainfall and other weather events. A forecast’s combined need for speed and accuracy taxes even the most modern computers. The future could take a radically different approach. A collaboration between the University of Washington and Microsoft Research shows how artificial intelligence can analyze past weather patterns to predict future events, much more efficiently and potentially someday more accurately than today’s technology. The newly developed global weather model bases its predictions on the past 40 years of weather data, rather than on detailed physics calculations. The simple, data-based A.I. model can simulate a year’s weather around the globe much more quickly and almost as well as traditional weather models, by taking similar repeated steps from one forecast to the next, according to a paper published this summer in the Journal of Advances in Modeling Earth Systems. “Machine learning is essentially doing a glorified version of pattern recognition,” said lead author Jonathan Weyn, who did the research as part of his UW doctorate in atmospheric sciences. “It sees a typical pattern, recognizes how it usually evolves and decides what to do based on the examples it has seen in the past 40 years of data.” Although the new model is, unsurprisingly, less accurate than today’s top traditional forecasting models, the current A.I. design uses about 7,000 times less computing power to create forecasts for the same number of points on the globe. Less computational work means faster results. That speedup would allow the forecasting centers to quickly run many models with slightly different starting conditions, a technique called “ensemble forecasting” that lets weather predictions cover the range of possible expected outcomes for a weather event – for instance, where a hurricane might strike. “There’s so much more efficiency in this approach; that’s what’s so important about it,” said author Dale Durran, a UW professor of atmospheric sciences. “The promise is that it could allow us to deal with predictability issues by having a model that’s fast enough to run very large ensembles.” Co-author Rich Caruana at Microsoft Research had initially approached the UW group to propose a project using artificial intelligence to make weather predictions based on historical data without relying on physical laws. Weyn was taking a UW computer science course in machine learning and decided to tackle the project. “After training on past weather data, the A.I. algorithm is capable of coming up with relationships between different variables that physics equations just can’t do,” Weyn said. “We can afford to use a lot fewer variables and therefore make a model that’s much faster.” To merge successful A.I. techniques with weather forecasting, the team mapped six faces of a cube onto planet Earth, then flattened out the cube’s six faces, like in an architectural paper model. The authors treated the polar faces differently because of their unique role in the weather as one way to improve the forecast’s accuracy. The authors then tested their model by predicting the global height of the 500 hectopascal pressure, a standard variable in weather forecasting, every 12 hours for a full year. A recent paper, which included Weyn as a co-author, introduced WeatherBench as a benchmark test for data-driven weather forecasts. On that forecasting test, developed for three-day forecasts, this new model is one of the top performers. The data-driven model would need more detail before it could begin to compete with existing operational forecasts, the authors say, but the idea shows promise as an alternative approach to generating weather forecasts, especially with a growing amount of previous forecasts and weather observations. Weyn is now a data scientist with Microsoft’s weather and finance division. This research was funded by the U.S. Office of Naval Research and a Department of Defense graduate fellowship. https://www.wsj.com/articles/how-ai-can-make-weather-forecasting-less-cloudy-11617566400 Sid Boukabara, principal scientist at the National Oceanic and Atmospheric Administration’s Center for Satellite Applications and Research, thinks those gains will be significant. “For certain components, it could be 10 times more efficient to 1,000 times more efficient.” But it is too early to know how much this will enhance the accuracy of numerical weather prediction as a whole. For instance, the European Center for Medium-Range Weather Forecasts currently simulates the globe as a grid of squares that are 9 kilometers on a side (roughly 5 miles) and stacked 137 layers up into the atmosphere. Deputy Director Peter Bauer says each step up in detail requires an exponential increase in electricity: The center’s newest supercomputer in Bologna, Italy, will consume as much power as 6,000 households. He and his colleagues are quickly approaching the limits of what they can afford or justify, he says. This year—relying on AI methods to boost efficiency—the center will begin developing a new global model at a 1-kilometer resolution that will bring storms and oceanic eddies into better focus, says Dr. Bauer. “Bigger and faster machines give us ever greater computing power, but we need to radically change the code we run on them to be able to use them effectively.”

All that we know is the new default winter and summer patterns since the super El Niño in 15-16. Warmer than normal winters with above normal snowfall. The two exceptions were the below normal snowfall winters in 18-19 and 19-20. But they were still warm. The summers since 16 have been warmer than average and more humid. The only outlier was the cooler 2017 summer but it was still humid. So it’s very difficult to know ahead of time when the coming season is going to deviate from recent experience.

No problem. The Central Park sensors used to be located in direct sunlight before the trees created deep shade. My rough calculation is that this has created an artificial 2° to 3° average maximum temperature summer JJA cooling since 1971. Notice how the mean summer high temperature increase at the other local stations since 1971 has been +2.7°.The high temperature staying steady at NYC instead of increasing was a function of trees blocking the sun. 1971 to 2020 summer JJA high temperature increase NYC….82.9….82.9…..0.0 LGA…..81.0….84.9….+3.9 EWR….83.4….85.4….+2.0 JFK…..80.1…..82.3..+2.2 ISP…….78.5…..81.6..+3.1 HPN….79.0….81.6…+2.6 BDR….79.1…..81.4…+2.3

The overgrowth of vegetation blocking the sensors has been well known for a while now. They would need to move the ASOS to a clearing away from any trees. The video below shows the correct sitting of weather sensors in parks or more rural settings. https://www.ncdc.noaa.gov/cdo-web/datasets/GHCND/stations/GHCND:USW00094728/detail Obstruction Descriptions OBSTRUCTIONS BEGIN DATE¹ END DATE¹ TREES 2021-04-06 Present TREES 2017-08-01 2021-04-06 TREE 020-340 deg 25-25 ft 20-54 deg 2016-06-15 2017-08-01 HYGR 090/4 TREES ENCIRLCE/25/20-54 IN FENCED ENCOLSURE 50 FT X 25 TH 1995-06-27 2016-06-15 UNIV 050/4 CRS 180/9 H083 SENSOR 200/8 TB 220/20 TREES ENCIRCLE/25/20-54 EQUIPMENT IN FENCED ENCLOSURE 50 FEET X 25 FEET 1992-01-01 1995-06-27 http://www.weather2000.com/ASOS/NYC_ASOS.html Central Park Weather: Vegetative Overgrowth Affecting Weather Readings - WABC-TV (New York-WABC, August 22, 2003) - Forecasting the weather is not easy. Government equipment can often be blamed for giving faulty weather information. As Bill Evans explains, a big culprit may be some of the equipment buried in Central Park. Rainfall, snowfall, and the temperature are all vital information recorded 24 hours a day at the weather station located in the heart of Central Park. But meteorologists like Michael Schlacter have serious concerns about the accuracy of the stations data. It sits amid overgrown vegetation and he says thats the problem. The leaves can trigger snow gauges and trees can warp rain and wind measurements. On this hot day, a temperature gauge is in the shade instead of direct sunlight. Michael Schlacter, Weather 2000: "Its kind of like driving a car without a speedometer, odometer, and gas gauge. You are running with false information." The weather instruments at Belvedere Castle have long adorned the top. There used to be a government meteorologist here in the city to keep an eye on them. But now the nearest meteorologist is 60 miles that way. But National Weather Service meteorologists say they knew the weather readings in the park would never be as keenly accurate as the ones at the airports where guidelines prevent foliage from being within 100 feet of the station. Schlacter: "We knew that at times we would have flaky readings, that leaves would fall in gauges, that we would have problems with visibility sensors." [NWS Meteorologist-in-Charge Michael] Wyllie says the weather station is there because it was historically significant to maintain its presence in the park. He says theres been a lot of growth because of the wet spring at so much in fact that temperatures have routinely been recorded lower in the park than at the airports. Wyllie: "We are actually having a micro climate system there because of the vegetation." Imperfect perhaps but nonetheless the system provides the official record of weather for the country's largest city. And Michael Schlacter says its a city that deserves better. Schlacter: "I think New Yorkers deserve a lot better, and I think they deserve the best weather station money can buy." Copyright 2003 ABC Inc., WABC-TV Inc.

This weekend actually looks like our last dry heat for a while. The next warm up on Wednesday is forecast to be more humid. So we may get back to the familiar 70° dewpoints. It would fit with the guidance showing better rain chances coming up.