bluewave

84/72 here along the South Shore.

Higher dew points holding on along the South Shore. 84/72 in Wantagh. Some fog coming ashore now in the Hamptons.

Yeah, the really impressive record high temperatures in recent years have come during the cold season. The new all-time monthly highs of 96°in October 2019 and 80° for February 2018. We have been lucky that the most extreme high temperatures haven’t been in July or August. But we saw that 108° new all time high at Newark in July 2011.

JFK came close on 7-21-19 with a 114/89 high and low on the heat index. https://mesonet.agron.iastate.edu/plotting/auto/?_wait=no&q=153&network=NY_ASOS&zstation=JFK&month=jul&var=max_feel&dpi=100&_fmt=png

Euro maxes out temperatures Sunday and Monday with the highest dew points Monday. Also has convection along a weak front on Monday. Should the convection and clouds hold off, then temperatures and heat indices would be higher Monday.

The minimum temperature departures to our north this month are pretty impressive, BTV...+6.1 ALB...+7.0 POU...+5.8 LGA....+4.8

The margin of the new record Is more impressive to our north if it can hold. Time Series Summary for ALBANY INTERNATIONAL AIRPORT, NY - Month of Jul Click column heading to sort ascending, click again to sort descending. Rank Year Lowest Min Temperature Missing Count 1 2020 62 15 2 2019 57 0 3 2008 56 0 - 2004 56 0 4 2011 54 0 - 2006 54 0 - 2005 54 0 5 2016 53 0 - 2014 53 0 - 2013 53 0 - 2012 53 0 - 1998 53 0 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 Lowest Min Temperature Missing Count 1 2020 67 15 2 2008 66 0 3 2019 65 0 - 1993 65 0 - 1970 65 0 - 1955 65 0

The warm minimums have been leading the departures In the Hudson Valley. POU is +4.4 so far. Max departure +3.1 and min +5.8. Climatological Data for POUGHKEEPSIE AIRPORT, NY - July 2020 Click column heading to sort ascending, click again to sort descending. Date Max Temperature Min Temperature Avg Temperature Avg Temperature Departure HDD CDD Precipitation Sum 1397 1058 - - 0 191 2.40 Average 87.3 66.1 76.7 4.4 - - - Normal 84.2 60.3 72.3 - 0 120 2.26 Above Normals represent the month through 2020-07-16. 2020-07-01 85 63 74.0 2.7 0 9 0.02 2020-07-02 94 60 77.0 5.5 0 12 0.07 2020-07-03 86 67 76.5 4.9 0 12 0.30 2020-07-04 91 67 79.0 7.2 0 14 0.00 2020-07-05 93 64 78.5 6.6 0 14 0.00 2020-07-06 95 65 80.0 8.0 0 15 0.00 2020-07-07 82 65 73.5 1.3 0 9 0.00 2020-07-08 83 69 76.0 3.7 0 11 1.34 2020-07-09 92 67 79.5 7.1 0 15 0.00 2020-07-10 82 69 75.5 3.0 0 11 0.39 2020-07-11 89 73 81.0 8.4 0 16 0.28 2020-07-12 88 70 79.0 6.3 0 14 T 2020-07-13 87 67 77.0 4.3 0 12 0.00 2020-07-14 88 63 75.5 2.7 0 11 0.00 2020-07-15 84 62 73.0 0.1 0 8 0.00 2020-07-16 78 67 72.5 -0.4 0 8 0.00 2020-07-17 M M M M M M M 2020-07-18 M M M M M M M 2020-07-19 M M M M M M M 2020-07-20 M M M M M M M 2020-07-21 M M M M M M M 2020-07-22 M M M M M M M 2020-07-23 M M M M M M M 2020-07-24 M M M M M M M 2020-07-25 M M M M M M M 2020-07-26 M M M M M M M 2020-07-27 M M M M M M M 2020-07-28 M M M M M M M 2020-07-29 M M M M M M M 2020-07-30 M M M M M M M 2020-07-31 M M M M M M M

Don, that matches up really well with our climate division rankings. New York Climate Division 4 Average Temperature June-August https://www.ncdc.noaa.gov/cag/divisional/time-series/3004/tavg/3/8/1895-2020 201006 - 201008 75.2°F 125 201606 - 201608 74.2°F 124 200506 - 200508 73.9°F 123 201106 - 201108 73.9°F 123 199906 - 199908 73.7°F 121 201206 - 201208 73.4°F 120 201806 - 201808 73.4°F 120 201906 - 201908 73.2°F 118 201506 - 201508 73.1°F 117 194906 - 194908 73.0°F 116

Long Island is on track for another top 5 highest average dew point July. This onshore flow pattern has kept the minimum temperature departures higher than the maximums. ISP has a max temperature departure of +1.7 and a min departure of +3.3. https://mesonet.agron.iastate.edu/plotting/auto/?_wait=no&q=76&network=NY_ASOS&station=ISP&season=jul&varname=dwpf&year=1893&hours=0-23&dpi=100&_fmt=png

I was wondering about that before I read this... https://www.weather.gov/media/owlie/2018-ASOS.pdf There are also some things that you would think affect the readings but generally don’t, such as jet exhaust. There are algorithms (computer code) in ASOS that take these quick fluctuations into account. These algorithms have been developed and tested to provide the most accurate and sensible data for a given sensor by using sampling over a period of time and other methods proven to weed out spikes in the sensor data that are caused by non-meteorological influences.

The actual sensors are located on a grassy strip. All of NYC is within feet of roadways and buildings. So I don’t see anything at that location that varies much from Queens of the other parts of NYC. These are the guidelines for airport ASOS sittings. https://www.faa.gov/documentLibrary/media/Order/6560_20c_ord.pdf

LGA follows the sitting rules at airports. The actual sensors are on a strip of grass with no obstructions. It’s representative of that part of Queens when there is an offshore flow. But it’s right on the water with cooling breeze when the flow in onshore. https://weather.gladstonefamily.net/site/search?site=KLGA

The site was fine before the trees and bushes became overgrown around the sensors. Like you said, the equipment should be located in a clearing away from any trees. The overgrowth really affected the number of 90°days following the ASOS installation in 1996. It artificially reduced the number of 90° days relative to the period before the ASOS. Average annual # 90° days 1970-1989.......2000-2019 NYC...18.0...........15.8 LGA....13.9...........22.3 EWR...23.3...........27.6 JFK....10.5...........11.1 ISP.......5.8.............8.0 Most recent photo in 2013

Yeah, it was part of all the early season close in tropical activity. It will be interesting to see what things look like once we approach the peak of the season. Some of the seasonal models have an active pattern for the Gulf and East Coast.

Yeah, the last 100 at JFK was back in 2013. The 2010-2013 period featured more westerly flow heat events. The subtropical high shifted further north and east since the super El Niño in 2015-2016. So our heatwaves since then have come with much higher humidity and S to SSE flow. But the higher heat indices made it feel like we have had numerous 100 degree days. https://mesonet.agron.iastate.edu/plotting/auto/?_wait=no&q=159&network=NY_ASOS&zstation=JFK&var=feel&dir=aoa&thres=100&month=all&year=2019&dpi=100&_fmt=png

The Euro has 75°+ dew points from Saturday through next Thursday. Some spots around the region may see their first 80° dew point of the season. JFK could be on its way to 5 consecutive years with double digit 75°+ dew point days. So a continuation of the high dew point surge which began with the 2015-2016 super El Niño. 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=2020&dpi=100&_fmt=js

Yeah, the bay breeze has been showing up quite a bit since 2016 at the airport. It wasn’t much of a factor from 2010 to 2013 when Newark had the deep westerly flow and all those 100+ days. The subtropical high has been just a little too far north and east in recent years.

Newark has had more SSE flow off the bay since the higher dew point surge began in 2016. But the Harrison station was just far enough from the bay to reach 100 several times. Time Series Summary for HARRISON, NJ - Month of Jul Click column heading to sort ascending, click again to sort descending. Year Highest Max Temperature Missing Count 2020 97 17 2019 101 0 2018 101 0 2017 98 0 2016 97 0 2015 98 0 2014 95 0 2013 102 0 2012 103 2 2011 107 1 2010 106 1

Looks like Sunday may be the next chance to go 95°+ in the usual warm spots. Euro has the sea breeze front with SSE winds near or just east of I-95. Could be some high dew point pooling near and east of the sea breeze front.

80°Julys have become more common since 2010. This July LGA is above and EWR is close. 80° used to be the average July temperature around the Washington DC area. Time Series Summary for LAGUARDIA AIRPORT, NY - Month of Jul Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 2010 82.8 0 2 1999 81.9 0 3 2020 81.5 18 - 2019 81.5 0 4 2013 81.2 0 5 2016 81.1 0 6 1955 80.9 0 7 1966 80.8 0 8 2006 80.7 0 9 1994 80.6 0 10 2012 80.4 0 - 2011 80.4 0 - 1952 80.4 0 11 2008 80.0 0 - 1993 80.0 0 12 2018 79.8 0 Time Series Summary for NEWARK LIBERTY INTL AP, NJ - Month of Jul Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 2011 82.7 0 2 1993 82.5 0 3 2010 82.3 0 4 1994 81.9 0 5 2013 80.9 0 6 2012 80.8 0 - 1999 80.8 0 7 2019 80.6 0 8 1955 80.5 0 9 1988 80.4 0 10 2002 80.0 0 11 2016 79.9 0 12 2020 79.6 18 - 1983 79.6 0 - 1966 79.6 0

Impressive first half of summer warmth to our north.

We need some new photos. http://www.weather2000.com/ASOS/NYC_ASOS.html June 2009 June 2013

So far the high temperature of the month at NYC and LGA is 96° and 95° at EWR. Latest model runs indicate that our next chance to go 95°+ is around the 20th. We’ll see if the models hold this day 6-10 forecast or back off again. The period around July 20th has been our warmest part of the month for 7 out of the last10 years. Highest July temperature and date at EWR or LGA since 2010 7-21-19........100 7-1-18...........98 7-20-17.........98 7-23/25-16...99 7-19-15.........98 7-2-14...........96 7-18-13........101 7-18-12........104 7-22-11........108 7-6-10..........103

Walt, thanks for the kind words. I have really enjoyed reading your forecast discussions over the years. From your AFDs during the late 90s in Boston to your present work on this forum. Yeah, it really comes down to the pattern as we approach the peak of the hurricane season.