bluewave

The record Western Ridge just won’t let up.

This was the 10th coldest 9-16 to 9-22 in NYC. It was also the coldest since 1993. 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 Sep 16 to Sep 22 Missing Count 1 1875-09-22 54.7 0 2 1871-09-22 55.8 0 3 1990-09-22 59.5 0 4 1929-09-22 59.6 0 5 1956-09-22 59.7 0 6 1993-09-22 59.8 0 7 1962-09-22 60.3 0 8 1879-09-22 60.4 0 9 1873-09-22 60.7 0 10 2020-09-22 60.9 0

These were my favorite seasons for snowstorm quality.... 17-18 15-16 10-11 02-03 95-96 82-83 81-82 77-78

I wonder if the EPS weeklies will be included with the free Euro maps in October?

One of my all-time favorites in Jan 2016 also. 10-11 could have surpassed 95-96 in spots had it continued another 30-45 days. 10-11 had snowstorm quality and extended snow cover. Maximum 33-Day Total Snowfall for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Rank Value Ending Date Missing Days 1 61.5 2011-01-27 0 2 53.6 2011-01-26 0 3 48.7 1978-02-14 0 4 45.7 1978-02-18 0 5 45.5 1961-02-16 0

Yeah, the continuous -EPO/+PNA was great if you liked cold and extended snow cover in 13-14 and 14-15. But the lack of -NAO left much to be desired in the KU extreme snowfall department. I will take individual snowstorm quality every time over extended snow cover and cold. Even if it means +13 in December or 80° in February.

The winter weather swings in recent years have been remarkable. With the exception of 10-11, all my recent favorite snowstorms have occurred during winters with some extreme warmth. 15-16...16-17...17-18....etc...I missed the best jackpots during the colder 13-14 and 14-15 winters.

That was the one. Record blizzard in January...first February 80°...30” of snow in March on Long Island. So the big winter weather swings which have been occurring more frequently in recent years. https://mashable.com/2018/01/04/bomb-cyclone-costal-flooding-boston/

Probably the best looking system in that region since the 950mb benchmark blizzard.

The record Western Ridge is our latest stuck weather pattern.

NYC just extended it to 4 days with the low of 49° so far today. The streak came several days earlier than 2000. 9-19....50° 9-20....50° 9-21....49° 9-22....49° 2000-09-26 54 50 52.0 -12.1 13 0 0.33 0.0 0 2000-09-27 68 47 57.5 -6.2 7 0 0.00 0.0 0 2000-09-28 67 49 58.0 -5.3 7 0 0.00 0.0 0 2000-09-29 59 43 51.0 -11.9 14 0 0.00 0.0 0 2000-09-30 65 48 56.5 -6.0 8 0 0.00 0.0 0

https://blogs.ei.columbia.edu/2019/07/30/co2-drives-global-warming/ Earth absorbs energy from sunlight, but as the surface warms, it also emits energy in the form of infrared radiation (which we know of as heat) out into space. Water vapor and CO2, however, act like a cap, making it more difficult for Earth to get rid of this energy. Without gases like these to absorb the energy, our planet’s average surface temperature would have been near zero degrees Fahrenheit. About 99 percent of the atmosphere is made of oxygen and nitrogen, which cannot absorb the infrared radiation the Earth emits. Of the remaining 1 percent, the main molecules that can absorb infrared radiation are CO2 and water vapor, because their atoms are able to vibrate in just the right way to absorb the energy that the Earth gives off. After these gases absorb the energy, they emit half of it back to Earth and half of it into space, trapping some of the heat within the atmosphere. This trapping of heat is what we call the greenhouse effect. Because of the greenhouse effect created by these trace gases, the average temperature of the Earth is around 15˚C, or 59˚F, which allows for life to exist. CO2 makes up only about 0.04% of the atmosphere, and water vapor can vary from 0 to 4%. But while water vapor is the dominant greenhouse gas in our atmosphere, it has “windows” that allow some of the infrared energy to escape without being absorbed. In addition, water vapor is concentrated lower in the atmosphere, whereas CO2 mixes well all the way to about 50 kilometers up. The higher the greenhouse gas, the more effective it is at trapping heat from the Earth’s surface. The burning of fossil fuels affects the concentration of CO2 in the atmosphere. Before the industrial revolution, the amount of CO2 in the atmosphere was about 288 ppm. We have now reached about 414 ppm, so we are on the way to doubling the amount of CO2 in the atmosphere by the end of this century. Scientists say that if CO2 doubles, it could raise the average global temperature of the Earth between two and five degrees Celsius. We are already increasing the amount of energy that bounces back to the Earth. Because of the greenhouse effect, this is causing global warming with its many destructive impacts. Both water vapor and CO2 are responsible for global warming, and once we increase the CO2 in the atmosphere, the oceans warm up, which inevitably triggers an increase in water vapor. But while we have no way to control water vapor, we can control CO2. And because we are increasing the amount of CO2 in the atmosphere by continuing to burn fossil fuels, even in relatively small amounts compared to the entire mass of the atmosphere, we are disturbing the entire heat balance of the planet.

Even 50-year-old climate models correctly predicted global warming https://www.sciencemag.org/news/2019/12/even-50-year-old-climate-models-correctly-predicted-global-warming By Warren CornwallDec. 4, 2019 , 12:00 PM Climate change doubters have a favorite target: climate models. They claim that computer simulations conducted decades ago didn’t accurately predict current warming, so the public should be wary of the predictive power of newer models. Now, the most sweeping evaluation of these older models—some half a century old—shows most of them were indeed accurate. “How much warming we are having today is pretty much right on where models have predicted,” says the study’s lead author, Zeke Hausfather, a graduate student at the University of California, Berkeley. Climate scientists first began to use computers to predict future global temperatures in the early 1970s. That’s when newfound computing power coincided with a growing realization that rising carbon dioxide levels could boost global temperatures. As the issue gained public attention, critics questioned the reliability of rudimentary model predictions. Even a 1989 news article in Science radiated skepticism, stating that “climatologists may have a gut feeling that the greenhouse effect is heating up Today, the models are much more sophisticated. Mainframe computers driven by paper punch cards have given way to supercomputers running trillions of calculations in 1 second. Modern models account for myriad interactions, including ice and snow, changes in forest coverage, and cloud formation—things that early modelers could only dream of doing. But Hausfather and his colleagues still wanted to see how accurate those bygone models really were. The researchers compared annual average surface temperatures across the globe to the surface temperatures predicted in 17 forecasts. Those predictions were drawn from 14 separate computer models released between 1970 and 2001. In some cases, the studies and their computer codes were so old that the team had to extract data published in papers, using special software to gauge the exact numbers represented by points on a printed graph. Most of the models accurately predicted recent global surface temperatures, which have risen approximately 0.9°C since 1970. For 10 forecasts, there was no statistically significant difference between their output and historic observations, the team reports today in Geophysical Research Letters. Global temperatures have risen approximately 0.9°C since 1970, though some areas have warmed much more than others. BERKELEY EARTH Seven older models missed the mark by as much as 0.1°C per decade. But the accuracy of five of those forecasts improved enough to match observations when the scientists adjusted a key input to the models: how much climate-changing pollution humans have emitted over the years. That includes greenhouse gases and aerosols, tiny particles that reflect sunlight. Pollution levels hinge on a host of unpredictable factors. Emissions might rise or fall because of regulations, technological advances, or economic booms and busts. To take one example, Hausfather points to a famous 1988 model overseen by then–NASA scientist James Hansen. The model predicted that if climate pollution kept rising at an even pace, average global temperatures today would be approximately 0.3°C warmer than they actually are. That has helped make Hansen’s work a popular target for critics of climate science. Hausfather found that most of this overshoot was caused not by a flaw in the model’s basic physics, however. Instead, it arose because pollution levels changed in ways Hansen didn’t predict. For example, the model overestimated the amount of methane—a potent greenhouse gas—that would go into the atmosphere in future years. It also didn’t foresee a precipitous drop in planet-warming refrigerants like some Freon compounds after international regulations from the Montreal Protocol became effective in 1989. When Hausfather’s team set pollution inputs in Hansen’s model to correspond to actual historical levels, its projected temperature increases lined up with observed temperatures. The new findings echo what many in the climate science world already know, says Piers Forster, an expert in climate modeling at the United Kingdom’s University of Leeds. Still, he says, “It’s nice to see it confirmed.” Forster notes that even today’s computer programs have some uncertainties. But, “We know enough to trust our climate models” and their message that urgent action is needed, he says. The new research is a useful exercise that “should provide some confidence that models can be used to help provide guidance regarding energy policies,” adds Hansen, now director of the Climate Science, Awareness and Solutions Program at Columbia University. He communicated with Science from Madrid, where world leaders are gathering this week for the 25th annual United Nations climate conference. Delegates from around the world are negotiating how to implement emissions cuts agreed to at the 2016 meeting in Paris. Meanwhile, a U.N. report issued last month showed greenhouse gas emissions have continued to climb since then, and that many of the biggest polluting countries aren’t on track to meet their promises.

This was the 6th earliest 46° on record at JFK. We haven’t seen a 46° this early since the 1970s. First/Last Summary for JFK INTERNATIONAL AIRPORT, NY Each section contains date and year of occurrence, value on that date. Click column heading to sort ascending, click again to sort descending. Year Last Value First Value Difference 1965 05-08 (1965) 45 08-31 (1965) 46 114 1967 06-01 (1967) 45 09-12 (1967) 46 102 1975 05-03 (1975) 46 09-15 (1975) 45 134 1961 05-28 (1961) 44 09-18 (1961) 46 112 1979 04-22 (1979) 45 09-20 (1979) 41 150 1962 05-13 (1962) 42 09-21 (1962) 42 130 1973 05-19 (1973) 44 09-21 (1973) 46 124

These days we need some type of record 500 MB blocking ridge to get cold. Looks like the ridge will build again to close out the month. Probably our best chance for rain in a while as the trough really digs into the GL.

Unusually cold readings for September which has seen the greatest monthly warming here in 30 years.

First 47° low in September at JFK since 1997. This is also the first September freeze at Sussex, NJ since the records began in 2001 on xmacis2. Kennedy Intl PTCLDY 47 39 74 NE6 Sussex CLEAR 31 29 92 CALM 30.58R Time Series Summary for JFK INTERNATIONAL AIRPORT, NY - Month of Sep Click column heading to sort ascending, click again to sort descending. Year Lowest Min Temperature Missing Count 2020 47 10 2019 49 0 2018 54 0 2017 54 0 2016 51 0 2015 56 0 2014 51 0 2013 48 0 2012 52 0 2011 50 0 2010 53 0 2009 50 0 2008 52 0 2007 50 0 2006 49 0 2005 50 0 2004 51 0 2003 52 0 2002 54 0 2001 50 0 2000 44 0 1999 51 0 1998 46 0 1997 47 0 Time Series Summary for SUSSEX AIRPORT, NJ - Month of Sep Click column heading to sort ascending, click again to sort descending. Year Lowest Min Temperature Missing Count 2020 31 10 2019 36 0 2018 44 0 2017 38 0 2016 36 8 2015 42 0 2014 39 0 2013 33 0 2012 37 1 2011 39 0 2010 38 0 2009 37 0 2008 37 0 2007 36 0 2006 34 0 2005 36 0 2004 40 0 2003 39 0 2002 38 0 2001 37 0

It will be fun to see what the convergence of the rapid software improvements and miniaturization look like. Smartphones have taken the lead on computational photography. While DSLR and mirrorless still appeal to many who like the larger sensor size and lens selections. Maybe the smartphone and mirrorless tech will merge in the coming decade or two. The gap is already narrowing.

Excellent points from Rclab and Liberty Bell. I remember the old days of photography when I would do all my own black and white darkroom printing after taking the photos. Switching over to digital allowed me to do more extensive color post processing. Smartphones really opened up the world of photography to many more people. There are some great photographers now who do much of their work on a iPhone or Android. But a dedicated bunch are still working on DSLR and mirrorless cameras. The old saying is the best camera is the one that you have with you.

The relationship that I have been looking at is the October MJO before a La Niña or Niña-like winter. October forcing over the Indian Ocean like last year was followed by less snowfall in NYC. The La Niña winters since 2000 with forcing near the Maritime Continent had better snowfall outcomes for NYC. October composite for a NYC 27.6”to 61.9”seasonal snowfall October composite before a NYC 4.8”to 20.5”snowfall season

We would need to see all that IO forcing shift east toward the Maritime Continent in October. The big amped up MJO 5 in October 2017 came before the snowy La Niña 17-18 winter. The strong IO MJO 1 in October 2011 preceded the 11-12 La Niña winter. There is some research that early IO forcing can excite the PV like we saw last winter.

We’ll see if we can get some early hints from the MJO in October. The 18-19 and 19-20 below normal snowfall La Niña background state winters featured the October MJO convection focused in the Indian Ocean. Our snowier 16-17 and 17-18 La Niña winters had the October MJO in the Maritime Continent phases.

Yeah, it does look like that big Western Ridge builds again to close out the month. So a deep trough in the Great Lakes would probably mean a wetter pattern for us. Any remnant tropical moisture from BETA would enhance our rainfall prospects.

The Euro and GFS have us getting back to the 80s by later in the week. But it looks like we will come up short on reaching 90°. So this could be the first fall since 2011 without any 90° degree days at Newark. The last fall at LGA without any 90s was 2012. Time Series Summary for NEWARK LIBERTY INTL AP, NJ - Sep through Nov Click column heading to sort ascending, click again to sort descending. Year Number of Days Max Temperature >= 90 Missing Count 2020 0 72 2019 4 0 2018 4 0 2017 3 0 2016 5 0 2015 5 0 2014 3 0 2013 1 0 2012 2 0 2011 0 0 2010 6 0 Time Series Summary for LAGUARDIA AIRPORT, NY - Sep through Nov Click column heading to sort ascending, click again to sort descending. Year Number of Days Max Temperature >= 90 Missing Count 2020 0 72 2019 3 0 2018 4 0 2017 1 0 2016 3 0 2015 3 0 2014 2 0 2013 1 0 2012 0 0 2011 0 0 2010 4 0

Looks like the first 26° September dew point at Newark since the late 90s. Newark/Liberty MOSUNNY 64 26 23 N12 https://mesonet.agron.iastate.edu/plotting/auto/?_wait=no&q=159&network=NJ_ASOS&zstation=EWR&var=dwpf&dir=below&thres=27&month=sep&year=2020&dpi=100&_fmt=png