bluewave

Very heavy downpour here in SW Suffolk with flash flooding developing. Due to the tropical nature of the rainfall, the radar is underestimating the rate of rainfall here. The echoes in orange are more like a red summer thunderstorm.

0.91 in 10 minutes and 1.56 in 20 at the peak.

The graph, shown above, looks at temperature patterns observed in the Pacific Northwest over the last 70 years and applies what is known as Generalized Extreme Value (GEV) theory to it. The fit, shown in red, looks pretty reasonable. 2/ One of the features of GEV is that it sometimes predicts that a statistical system as a finite limit. That occurs when the data presents a downward curving slope, as it does here. 3/ To be concrete, the analysis presented above says: In the 70 years prior to 2021, the worst observed heatwave for the region corresponds to an average of ~35 °C (95 °F). The GEV model estimates the worst possible is ~37 °C (99 °F). But in 2021, we reached 39.5 °C (103 °F). 4/ The GEV model said that 39.5 °C was "impossible", but it happened anyway. Now obviously, if it happened then it was actually possible, so what is it really telling us? 5/ It suggests that the 2021 heatwave may have had a qualitatively different origin or dynamics than all the other Pacific Northwest heatwaves of the last 70 years. 6/ That kind of thing happens sometimes with extremes in physical systems. For example, 70 years of normal rain data may badly fail to predict how much rain is possible during a hurricane, because a hurricane is dynamically different from normal rain-producing processes. 7/ The statistics suggest that the Pacific Northwest heat storm was not merely more extreme than past events, but perhaps also qualitatively different. So, *if* the event was qualitatively different from past events, then we ask in what way? 8/ The first option is that the heat storm was a proverbial hurricane, e.g. a rare dynamical interaction that has always been possible, but so rare that in 70 years of data we never observed a weather pattern that was qualitatively similar. 9/ The second option is that we are seeing unfamiliar dynamics because the climate system has changed at large scales in ways we don't yet fully understand. I consider this the scarier option. 10/ Right now, we don't know the answer. In all likelihood, entire PhDs will be written about the Pacific Northwest heat storm. But nature has thrown us a scary curve ball, and we'll have to wait and see if this was just an exceedingly rare one-off or a sign of more to come. 11/11

Pretty good 12z agreement on the axis of heaviest rains right through NYC Metro.

Central Park OBS since 1991 being much cooler than Newark is an illusion created by the trees growing over ASOS. When the sensors were free of obstructions like all official weather sites, NYC would be equal to or warmer than Newark on some days. The ASOS back in the 30s to 70s was in a more open area like the softball fields are today. That’s the only reason why the warmest week in Central Park can’t get warmer than 1977. Notice how our other stations have had their warmest week in more recent times. NYC ASOS beneath a dense canopy marked KNYC That area was more open before the tree growth of the last 40 to 50 years like nearby softball fields. Warmest weeks around our area Maximum 7-Day Mean Avg Temperature for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Rank Value Ending Date Missing Days 1 91.2 1993-07-13 0 Maximum 7-Day Mean Avg Temperature for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Rank Value Ending Date Missing Days 1 87.4 1993-07-13 0 87.4 1977-07-21 0 Maximum 7-Day Mean Avg Temperature for LAGUARDIA AIRPORT, NY Click column heading to sort ascending, click again to sort descending. Rank Value Ending Date Missing Days 1 88.3 2006-08-03 0 Maximum 7-Day Mean Avg Temperature for WESTCHESTER CO AP, NY Click column heading to sort ascending, click again to sort descending. Rank Value Ending Date Missing Days 1 83.4 2013-07-20 0 Maximum 7-Day Mean Avg Temperature for JFK INTERNATIONAL AIRPORT, NY Click column heading to sort ascending, click again to sort descending. Rank Value Ending Date Missing Days 1 86.4 2013-07-21 0 Maximum 7-Day Mean Avg Temperature for ISLIP-LI MACARTHUR AP, NY Click column heading to sort ascending, click again to sort descending. Rank Value Ending Date Missing Days 1 84.3 2013-07-20 0 Maximum 7-Day Mean Avg Temperature for IGOR I SIKORSKY MEMORIAL AIRPORT, CT Click column heading to sort ascending, click again to sort descending. Rank Value Ending Date Missing Days 1 84.8 2013-07-20 0

This is a continuation of the stronger WAR with a more tucked in storm track like the last several years. New run Old run

This reminds me of the Indian monsoon pattern. Record heat in June followed by heavy rains in July. It’s a Newark record for early July rain following 100°+ heat in late June. Time Series Summary for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Rank Ending Date Total Precipitation Jul 1 to Jul 7 Max Temperature Jun 24 -30 1 1984-07-07 4.83 90 2 2021-07-07 3.07 103 3 1989-07-07 2.86 96 - 1942-07-07 2.86 88 4 2017-07-07 2.62 91 5 2014-07-07 2.60 89

Gusted to around 40 mph here in SW Suffolk. Very heavy downpours with several close CG strikes.

LGA gusting to 58 mph. 06 Jul 6:31 pm 90 62 40 NW 32G58 10.00 Thunder, Squalls SCT065,BKN100,BKN250 29.91

Newark gusting to 58 mph. 06 Jul 6:30 pm 84 61 45 NW 43G53 7.00 BKN065,BKN100 29.92 29.94 06 Jul 6:29 pm 84 61 46 NW 43G58 7.00 Thunder BKN065,BKN100,BKN250 29.92 29.94 06 Jul 6:25 pm 88 61 41 NW 31G52 7.00 SCT065,BKN100 29.91 29.93 06 Jul 6:22 pm 93 65 40 NW 36G48 7.00 Thunder SCT065,BKN100,BKN250 29.91 29.93

The ASOS is on a grassy area near the eastern edge of the airport close to a creek. Our local airports are similar to the adjacent neighborhoods. Newark and Elizabeth have been built up for ages like most of our urban areas.

July 1953 also. Data for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Date Max Temperature Min Temperature 1953-07-17 100 76 1953-07-18 101 78 Data for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Date Max Temperature Min Temperature 1953-07-17 99 77 1953-07-18 99 76

The only day that I can find was 7-18-77. Data for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Date Max Temperature Min Temperature 1977-07-13 93 73 1977-07-14 92 73 1977-07-15 96 72 1977-07-16 98 75 1977-07-17 97 78 1977-07-18 100 78 1977-07-19 102 78 1977-07-20 92 75 1977-07-21 104 78 Data for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Date Max Temperature Min Temperature 1977-07-13 92 73 1977-07-14 91 73 1977-07-15 93 71 1977-07-16 97 72 1977-07-17 99 77 1977-07-18 98 75 1977-07-19 100 78 1977-07-20 90 75 1977-07-21 102 78

Tree and shrub growth in Central Park really began to block the sun from reaching the sensor around 1991. From 1931 to 1991, NYC was generally -2 to +2 warmer than Newark. This was before the deep shade during the peak daily heating hours at the NYC ASOS. Since 1991, NYC has been about -2 to -4 cooler than Newark for the years that went to 100° or greater at Newark. So it’s quite possible that the trees being too close in 2011 prevented NYC from making a run at the 1936 all-time record. Years with a Tie and NYC in the lead bolded 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 Highest Max Temperature NYC Max Temperature 1 2011 108 104….-4 2 2001 105 103….-2 - 1993 105 102….-3 - 1966 105 103….-2 - 1953 105 102….-3 - 1949 105 102….-3 3 2012 104 100…-4 - 1995 104 102….-2 - 1936 104 106…+2 4 2021 103 98….-5 - 2010 103 outage missed high 103……? - 1999 103 101….-2 - 1954 103 100….-3 - 1948 103 103…..T 5 2005 102 99….-3 - 1994 102 98….-4 - 1991 102 102….T - 1977 102 104.+2 - 1952 102 100…-2 - 1944 102 102...T - 1943 102 99…-3 6 2013 101 98….-3 - 2006 101 97….-4 - 1997 101 97….-4 - 1988 101 99…-2 - 1980 101 102…+1 - 1957 101 101…..T - 1955 101 100….-1 - 1933 101 102….+1 7 2002 100 98….-2 - 1986 100 98….-2 - 1982 100 98….-2 - 1973 100 98….-2 - 1963 100 98…-2 - 1959 100 97…-3 - 1937 100 100…T - 1934 100 101….+1

The 99th percentile event, by definition, occurs 1 day in 100. Since there are 92 days in the Jun-Aug period, it is approximately a 1 year event. 2/ Because temperatures are recorded in whole degrees °F and the differences are typically in the small single digits, the map has a somewhat mottled appearance. 3/ If you remove "major" big city stations, the map looks almost identical and the gridded average only changes by 0.06°F. 4/ Finally, what about all that blue??? It's well understood that decades of land use and irrigation changes in the Great Plains has led to less extreme summer temperatures over the decades. This is, quite literally, a human induced change of the climate. 5/5

We are on track for the first two Julys in a row with a tropical storm around the 9th-10th. Area Forecast Discussion National Weather Service New York NY 232 PM EDT Fri Jul 10 2020 .SYNOPSIS... Tropical Storm Fay will move northward along the Mid Atlantic coast today Latest EPS Elsa forecast

Plenty of smoke from the wildfires.

The June heat this year was very unusual on several fronts. The all-time heat records in the West occurred in June instead of July. All-time heat records are usually set in July. The Newark 103° at the end of June and 597 dm ridge were also early. So we’ll have to see if this means a rare June highest temperature. The active convection pattern coming up also feels like what we see sometimes in August after late July hottest temperatures of the summer.

The latest EPS weeklies have an active storm track the next few weeks. So it’s possible that the 103°at Newark last week won’t get surpassed for a while. Sometimes it can be tough to rival a heatwave once a pattern becomes wetter. July 5-12 July 12-19

Yeah, the corn has kept the Plains cooler than the East and West. 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. 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 Euro has more +20 C 850 mb temps Tuesday and Wednesday. It will be interesting to see if the smoke is thick enough to prevent more 100° readings. Tough to tell how much if any influence it will have on our temperatures.