bluewave

The unusually strong 500 mb anomaly over Canada allowed us to escape the major heat this July that has been common since 2010. Time Series Summary for NEWARK LIBERTY INTL AP, NJ - Month of Jul Click column heading to sort ascending, click again to sort descending. Year Mean Avg Temperature Missing Count 2021 79.1 5 2020 80.8 0 2019 80.6 0 2018 78.2 0 2017 77.3 0 2016 79.9 0 2015 79.0 0 2014 77.0 0 2013 80.9 0 2012 80.8 0 2011 82.7 0 2010 82.3 0 Time Series Summary for LAGUARDIA AIRPORT, NY - Month of Jul Click column heading to sort ascending, click again to sort descending. Year Mean Avg Temperature Missing Count 2021 77.9 5 2020 82.9 0 2019 81.5 0 2018 79.8 0 2017 78.1 0 2016 81.1 0 2015 79.2 0 2014 77.0 0 2013 81.2 0 2012 80.4 0 2011 80.4 0 2010 82.8 0

So far this is the second most positive summer AO on record for the June into July period. 2016 wasn’t nearly as positive for this first half of summer interval. If the lower pressures were more aligned with the AO region, then it would be even more positive. That’s why the raw indices don’t always tell the complete story. It would be nice to have the daily AD anomaly to combine the two indices for a more complete picture. You can see the Arctic pressures were lowest in the series for the month of June just edging out 1970.

JFK was able to set its highest dew point record of 84° in 2016. But you can see how all the highest records were in recent years. The mid-July 1995 heatwave was impressive for several sites reaching the 100/80 mark.

This is actually the lowest Arctic pressures for the first half of summer since 1989. Looking at the raw indices like the AO doesn’t really do this pattern justice. While the core of the low pressure is closer to the Russian side this summer, the overall Arctic pressures haven’t been this low in the post 2007 era. In the much cooler late 80s with the healthier ice pack, we would be talking about a September daily minimum extent near 7 million sq km like 1989. But we’ll have to settle for whatever passes for good in the post 2007 Arctic this year.

That was 2018. JFK is currently at 7 days with a 75° or higher dew point . Only 3 more days needed for the first 6 year run. https://mesonet.agron.iastate.edu/plotting/auto/?_wait=no&q=161&network=NY_ASOS&zstation=JFK&var=max_dwpf&dir=aoa&thres=75&month=all&year=2021&dpi=100&_fmt=js

Yeah, more record rainfall and flooding.

Another top 10 highest dew point July at JFK and ISP. https://mesonet.agron.iastate.edu/plotting/auto/?_wait=no&q=76&network=NY_ASOS&station=JFK&season=jul&varname=dwpf&year=1893&w=bar&hours=0-23&dpi=100&_fmt=png

A combination of a warmer atmosphere holding more moisture and slower moving systems.

Another 2.31 on the North Shore with the thunderstorms last night. This brings the Port Washington total to 14.31 for July so far. This probably ranks among the heaviest July rainfall totals ever recorded on Long Island. NY-NS-27 Port Washington 0.8 N Lat: 40.839167 Lon: -73.68025 * indicates Multi-Day Accumulation Report Station NY-NS-27 Date Precip in. 07/01/2021 1.04 07/02/2021 1.12 07/03/2021 2.26 07/04/2021 0.79 07/05/2021 0.00 07/06/2021 0.00 07/07/2021 0.43 07/08/2021 0.01 07/09/2021 3.07 07/10/2021 2.06 07/11/2021 0.02 07/12/2021 0.21 07/13/2021 0.04 07/14/2021 0.02 07/15/2021 T 07/16/2021 0.00 07/17/2021 0.00 07/18/2021 0.28 07/19/2021 0.05 07/20/2021 0.01 07/21/2021 T 07/22/2021 0.34 07/23/2021 0.01 07/24/2021 0.00 07/25/2021 0.22 07/26/2021 2.33 Totals : 14.31 in.

Yeah, these rainfall extremes are occurring all across the world. This is officially the wettest monsoon on record to date in Tucson. Also notice how the intensity of the monsoon produced the record cool temperatures in Phoenix.

Yeah, looks like this will be the 6th month since 2010 that at least one of our major stations goes 10.00”+. August 2011 was the last time all our stations went 10.00” in the same month. It will be interesting to see if we can eventually get a 10.00” winter month in the coming years. The only one in NYC history was Jan 1979. But out of 10.59, only 6.6 fell as snow. I wonder what the highest precipitation total winter month we can get and still have most of it fall as snow? Philly picked up 5.75 in Feb 2010 and 51.5 of that was snow. NYC got 6.69 in Feb 2010 and 36.9 was snow. Be interesting to see the maximum snowfall we can get from a 10.00 winter month. Jul….2020….EWR…11.20 Aug..2014…..ISP……14.07 Jun..2013……NYC….10.10 Aug..2011……EWR….18.79…..other stations in same range Mar…2010…..NYC…..10.69

Flash flooding today in London.

Albany was a cool oasis in a sea of warm back in June. ALB….-0.2 POU…+2.8 BTV….+4.3 BGM..+3.4 SYR…+5.5

June was a top 1-5 warmest for the Northeast. But July only ranks In the top 20s for many spots. This is one of the biggest temperature ranking declines from June to July that we have ever seen.

This is one of the more impressive temperature gradients that we have seen this time of year. So an up and down temperature pattern. With all the quick changes, there will be something for everyone.

This is the first time in the post 2010 era that Newark experienced such a big monthly maximum temperature drop from June to July. Monthly Highest Max Temperature for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Year Jun Jul Season Mean 96 100 +4 2021 103 97 -6 2020 93 96 +3 2019 93 99 +6 2018 96 98 +2 2017 99 98 -1 2016 91 99 +8 2015 93 98 +5 2014 92 96 +4 2013 96 101 +5 2012 99 104 +5 2011 102 108 +6 2010 98 103 +5

With all the blocking, areas just N and W of NYC could see 50s next weekend.

This is the 15th day in July so far with rain in NYC. It’s the most since 1996. So NYC is getting closer to only the 3rd 10.00” July. Time Series Summary for NY CITY CENTRAL PARK, NY - Month of Jul Click column heading to sort ascending, click again to sort descending. Rank Year Number of Days Precipitation >= .01 Missing Count 1 1871 20 0 2 1992 16 0 - 1988 16 0 - 1969 16 0 - 1958 16 0 - 1945 16 0 - 1919 16 0 - 1915 16 0 - 1901 16 0 - 1887 16 0 3 1996 15 0 - 1938 15 0 - 1897 15 0 - 1889 15 0 2021 15 6 Time Series Summary for NY CITY CENTRAL PARK, NY - Month of Jul Click column heading to sort ascending, click again to sort descending. Rank Year Total Precipitation Missing Count 1 1889 11.89 0 2 1975 11.77 0 3 1897 9.56 0 4 2021 9.21 7 5 1928 8.89 0

Hard to keep track of all the record flash flooding around the world. Luckily, the driver survived.

This would be a great winter pattern.

That chart above is using the flawed UAH from before it was corrected.

I have never heard of an ASOS system being moved after it was built. The best time to have done that was before they installed it back in 1995. I don’t think there is a budget for moving weather stations.

Yeah, that’s why NYC was often the warmest spot in the 60s and 70s with no trees covering the equipment. Can you imagine how many high temperature records would have been broken since 1990 if the site was properly maintained? Sometimes you have to laugh when tuning into the local NYC TV and radio weather reports. The usual story is how NYC just missed a heatwave with a high of only 88° or 89° degrees. Then report ends with but they got the heatwave at EWR or LGA. So it gives the impression that Manhattan is a great spot beat the summer heat.

You could probably do a a documentary on all the problems that the Central Park station has had over the years. https://www.nytimes.com/1977/07/22/archives/vandals-in-central-park-forcing-weather-service-to-seek-new-site.html Besides taking New York City's temperature and trying to predict when it will go up or down. National Weather Service forecasters are searching for a new place in Central Park to keep the sensitive instruments they use to prepare their hourly reports. “It's really a sh‐me, but we have to move,” said Harold Gibson, the meteorologist in charge of the New York bureau, as he stepped carefully through the debris at the crumbling Belvedere Castle, where weather data is collected and transmitted electronically to Weather Service headquarters in Rockefeller Center. Mr. Gibson said he decided to leave the hilltop castle, which is the highest point in the park, because he cannot predict the frequency of break‐ins that interrupt the monitoring of temperature, humidity, sunlight and wind at the unmanned station in the unguarded, city‐owned castle, which is south of the Delacorte Theater at 79th Street on the west side of the park. Vandalism Disrupts Work “Mostly we suffer from malicious destruction,” Mr. Gibson said. “The problem up here can be as little as somebody pulling a circuit‐breaker switch that stops the current and halts the measurements. But from our standpoint, that's almost as bad as stealing all the equipment—it disrupts our work.” The last break‐in occurred two weeks ago. The thermometer was not damaged, but the anemometer, which meastures wind speeds, was stolen, and other equipment has not functioned properly since. Some of the forecasters work in windowless rooms and cannot tell whether the sun is shining without the Central Park equipment. As a result, visitors to the Weather Service office at Rockefeller Center are sometimes asked what the weather outside is like. When the devices at the castle are not functioning, the Weather Service substitutes readings from La Guardia Airport. But Mr. Gibson said those readings do not really reflect conditions in the city, because they may be several degrees cooler in summer or warmer in winter than those in Central Park. During the current hot spell, the Weather Service has used wind and humidity readings from La Guardia in its forecasts. Replacing the Central Park equipment is fairly expensive—an anemometer costs about $2.500, Mr. Gibson said—but the forecasers arc reluctant to install replacements because they fear another break‐in. “Whoever does this to us is speedy,” Mr. Gibson said, recalling_ one break‐in that had occurred in the morning. By 2:30 P.M. the repairs were completed. No sooner was the 4 P.M. forecast released than the new equipment was stolen. The police have increased the number of patrols passing the castle, and that has deterred some vandals, Mr. Gibson said. And the Parks Department put steel gratings over the windows after vandals smashed through the concrete blocks that had been installed in place of the semicircular windows. “Clearly, that's not enough,” said Joseph P. Bresnan, director of historic parks, monuments and restoration. “That building should be used.” Meanwhile, the stonework at the castle, which was designed by Calvert Vaux, a collaborator wtih Frederick Law Olmsted on the design of Central Park, has been frescoed with graffiti. A $557,000 project to restore the castle, the top priority item in a 1973 study of Central Park, has been put off indefinitely because of the city's economic problems. One possible site for housing the sensitive instruments is the roof of the Central Park Precinct station house, which the police have offered. It is only a short distance from the castle, and meteorologists think the climate conditions there are almost identical to those at Belvedere, where weather data have been gathered for 109 years. “It would be almost criminal to destroy the century‐old data base we have accumulated here at Central Pork.” Mr. Gibson said. “It is one of the best in the United States, or, for that matter, in the world.”

JFK has seen a similar rise in JJA temperatures as the other stations. You can see the big giveaway that the NYC ASOS went from the sun to deep shade. Notice how the average minimum JJA temperature rose in line with the other stations since 1951-1980. But the average high from 1951-1980 to 2011-2020 is virtually unchanged. JJA 1950-1981 to 2011-2020 temperature change NYC max….83.0…83.2….+0.2 min…..66.0…68.2….+2.2 EWR max…83.4…85.3…..+1.9 min….65.8….67.8…..+2.0 LGA max…82.0….84.4…..+2.4 min….66.8….69.9…..+3.1 JFK max….80.5….82.5…..+2.0 min…..65.4….67.7……+2.3