bluewave

Another 75° at Islip brings them to within one day of the all-time record. Time Series Summary for ISLIP-LI MACARTHUR AP, NY - Jan through Dec Click column heading to sort ascending, click again to sort descending. Rank Year Number of Days Max Temperature >= 75 Missing Count 2007 120 0 1991 120 0 2021 119 89 2010 118 0 2011 117 0 2005 116 0 2001 116 0 2016 115 0 2015 115 0 2018 114 0 2017 113 0 2020 112 0 2014 112 0 1980 112 0 1998 111 0 2013 110 0

We haven’t had a cold October since 2009.

Continuation of the extended warmth theme following brief periods of slightly cooler than normal temperatures. Our last -10 departure day was way back on the July 4th weekend. The coldest departure of the whole year so far was during the Memorial Day weekend. https://mesonet.agron.iastate.edu/plotting/auto/?_wait=no&q=32&network=NYCLIMATE&station=NYC004&year=2021&var=avg&gddbase=50&gddceil=86&how=diff&cmap=jet&dpi=100&_fmt=png

The minimum at NYC was lower than EWR and LGA. But you can see the deep shade shaving at least 3°off the high temperature. The high temperature on the Great Lawn in Central Park was probably around 70°instead of 67° in the deep shade near the castle. LGA………….…....70/54 NYC………………..67/51 JFK………………...70/50 EWR………………..72/52 FRG…………………68/49 ISP………..……...…68/49 Brownsville …….73/54 Ozone Park……..71/52

October has been one of our fastest rising temperature months of the fall along with September. The area just experienced the warmest October on record back in 2017. The highest monthly maximum temperature record was set in 2019 with the flash drought and mid 90s. It’s also interesting that most 60° Octobers have been La Ninas. Time Series Summary for NEWARK LIBERTY INTL AP, NJ - Month of Oct Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature ENSO 2017 63.8 La Niña 2007 63.5 La Niña 1971 63.1 La Niña 1990 62.4 Neutral 1984 62.2 La Niña 1949 61.6 La Niña 1963 61.2 El Niño 1995 61.0 La Niña 1947 61.0 Neutral 2019 60.4 Neutral 1954 60.4 La Niña 1973 60.3 La Niña 1946 60.0 El Niño

With how warm it has been, the -2.7 average departure felt much cooler today. 6 station average..-2.7 EWR…..-1 NYC…..-5 LGA……-3 JFK……-3 ISP…….-2 BDR……-2

The 70° at Newark yesterday and today is in line with the warmer spots in the 5 Boroughs of NYC. The NYC micronet is a great addition to our urban observations. Notice how there were several 70° highs yesterday. Ozone Park is currently at 70° this afternoon. https://www2.nysmesonet.org/networks/nyc 9-30 highs… Bensonhurst / Mapleton 70 Brownsville 70 Highs so far today Lefferts / South Ozone Park Temp: 70°F 3h Precip: 0.00″

Sure. It’s getting to the point that we need extreme blocking even for a brief cooldown. The nearly 5sd block over that part of Canada looks like a new record for this time of year. But it builds quickly southward and merges with the SE Ridge for a quick warm up. My guess is that the models continue this warmer ridge well into October since it’s part of the La Niña forcing pattern. But even for a La Niña pattern in October, this ridge is on the extreme side as we have been seeing with the 500 mb patterns.

It would be great if the NYC ASOS in Central Park got this type of attention to its accuracy. PUBLIC INFORMATION STATEMENT NATIONAL WEATHER SERVICE ALBANY NY 752 AM EDT THU SEP 30 2021 ...PUBLIC INFORMATION STATEMENT... ...NATIONAL WEATHER SERVICE REPLACEMENT OF THERMOMETER AT ALBANY INTERNATIONAL AIRPORT... THE NATIONAL WEATHER SERVICE RECONDITIONING CENTER (NWSRC) REPLACED THE AUTOMATED SURFACE OBSERVING SYSTEM THERMOMETER AND ASSOCIATED ELECTRONICS AT THE ALBANY INTERNATIONAL AIRPORT YESTERDAY, SEPTEMBER 29, 2021 AT 9:30 AM. THE THERMOMETER WAS REPLACED WITH A MODIFIED SENSOR AND CALIBRATED WITH A MODIFIED ALIGNMENT PROCEDURE. A REFERENCE THERMOMETER, RUNNING SIDE BY SIDE WITH THE ASOS THERMOMETER, HAS COLLECTED DATA FOR COMPARISON SINCE JUNE. THE PREVIOUS THERMOMETERS INSTALLED SINCE JULY 17, 2020 LIKELY HAD A COLD BIAS (THERMOMETER RECORDS A COLDER TEMPERATURE THAN THE ACTUAL TEMPERATURE). THE NATIONAL WEATHER SERVICE WILL CONTINUE THE INVESTIGATION ON THE COLD BIAS IN THE ALBANY TEMPERATURE RECORD FOR THE PERIOD JULY 17, 2020 THROUGH SEPTEMBER 29, 2021. PLEASE CONTACT SUSAN BUCHANAN, DIRECTOR OF PUBLIC AFFAIRS, NATIONAL WEATHER SERVICE AT 301-427-9000 FOR ADDITIONAL INFORMATION. $$ 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.

Only the third time that ISP had the first 40s of the season as late as October. The other two years were 2015 and 2018. The low of 53 before midnight yesterday was also the warmest September monthly minimum temperature. First/Last Summary for ISLIP-LI MACARTHUR AP, 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 2018 06-12 (2018) 48 10-12 (2018) 49 121 2015 05-23 (2015) 48 10-02 (2015) 49 131 2003 06-03 (2003) 48 09-30 (2003) 45 118 2002 06-08 (2002) 46 09-29 (2002) 49 112 1970 05-31 (1970) 48 09-29 (1970) 46 120 1980 06-12 (1980) 47 09-27 (1980) 48 106 2016 05-23 (2016) 49 09-25 (2016) 48 124 2005 05-28 (2005) 48 09-25 (2005) 49 119 1987 06-07 (1987) 49 09-25 (1987) 42 109 2014 06-01 (2014) 49 09-23 (2014) 45 113 1998 06-10 (1998) 47 09-23 (1998) 44 104 1974 05-28 (1974) 42 09-23 (1974) 46 117 1976 06-13 (1976) 49 09-22 (1976) 46 100 2008 05-30 (2008) 47 09-21 (2008) 48 113 1981 06-08 (1981) 47 09-21 (1981) 47 104 2004 05-30 (2004) 41 09-20 (2004) 49 112 Time Series Summary for ISLIP-LI MACARTHUR AP, NY - Month of Sep Click column heading to sort ascending, click again to sort descending. Rank Year Lowest Min Temperature Missing Count 1 2021 53 0 2 2015 52 0 3 2018 51 0

Updated for September 2021. 9…2021…..EWR…..4…..LGA…..7…..JFK……7……..BDR…..5….ISP….4

Another top warmest September across the area. Time Series Summary for NEWARK LIBERTY INTL AP, NJ - Month of Sep Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 1961 74.5 0 2 2005 73.5 0 3 2015 73.4 0 4 2021 72.5 0 5 2016 71.8 0 - 1971 71.8 0 6 2010 71.6 0 7 1959 71.5 0 8 2018 71.4 0 9 2011 71.2 0 10 1973 71.0 0 - 1931 71.0 0 Time Series Summary for LAGUARDIA AIRPORT, NY - Month of Sep Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 2005 74.9 0 2 2015 74.1 0 3 2016 73.8 0 4 1961 73.6 0 5 2007 73.0 0 6 2018 72.8 0 7 2021 72.7 0 8 2010 72.5 0 - 1959 72.5 0 9 2019 72.1 0 10 1998 71.6 0 Time Series Summary for JFK INTERNATIONAL AIRPORT, NY - Month of Sep Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 2015 73.0 0 - 1961 73.0 0 2 2005 72.1 0 3 1971 71.8 0 4 1959 71.3 0 5 2016 71.1 0 6 1983 71.0 0 7 2021 70.7 0 - 2018 70.7 0 8 2017 70.6 0 9 2010 70.5 0 Time Series Summary for ISLIP-LI MACARTHUR AP, NY - Month of Sep Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 2015 70.9 0 2 2005 70.2 0 3 2018 69.8 0 4 2021 69.6 0 - 1980 69.6 0 5 2017 69.0 0 - 2011 69.0 0 6 2016 68.9 0 7 1998 68.6 0 8 2010 68.3 0 9 1983 68.1 0 - 1971 68.1 0 10 2008 67.7 0 Time Series Summary for IGOR I SIKORSKY MEMORIAL AIRPORT, CT - Month of Sep Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 2015 71.1 0 2 2016 70.6 0 3 1961 70.5 0 4 2011 70.1 0 5 2021 69.8 0 - 2005 69.8 0 6 2018 69.5 0 7 1959 69.4 0 8 2010 69.3 0 9 2017 69.1 0 10 1971 69.0 0

Yeah, October 1st may be our coolest temperature departures for a while. EPS Oct 4-11 Oct 11-18

A return to warmer than average temperatures following a brief cooler to near normal first day of the month. This matches up with September and October being the fastest warming months of fall. The monthly temperature increases from 81-10 to 91-20 have been more pronounced during certain months. Newark and Islip are compared below. The +1.0 or warmer months for either station were bolded. So we get an extension of summer into September. ……….EWR…..ISP Dec…+1.5….+1.5 Jan….+1.2…+1.3 Feb….+0.5….+0.5 Mar….+0.4….+0.6 Apr….+0.5…..+0.6 May...+0.6….+0.9 Jun….+0.3….+0.6 Jul…..+1.4…..+1.1 Aug...+0.6….+0.9 Sep….+1.0….+1.3 Oct…..+0.9..+1.4 Nov….+0.2..+0.5

The lack of any real cold air for September shows up with monthly minimum temperatures in the top 3 warmest. New records were set at EWR, BDR, and ISP. This reflects how fast the September temperatures have been rising. Time Series Summary for ISLIP-LI MACARTHUR AP, NY - Month of Sep Click column heading to sort ascending, click again to sort descending. Rank Year Lowest Min Temperature Missing Count 1 2021 54 1 2 2015 52 0 3 2018 51 0 4 2017 49 0 - 2011 49 0 - 2004 49 0 - 2002 49 0 Time Series Summary for WESTCHESTER CO AP, NY - Month of Sep Click column heading to sort ascending, click again to sort descending. Rank Year Lowest Min Temperature Missing Count 1 2018 51 0 2 2021 48 1 - 2008 48 0 - 2002 48 0 - 1999 48 2 - 1968 48 0 Time Series Summary for NEWARK LIBERTY INTL AP, NJ - Month of Sep Click column heading to sort ascending, click again to sort descending. Rank Year Lowest Min Temperature Missing Count 1 2021 55 1 2 2015 54 0 3 2018 53 0 - 2002 53 0 - 1994 53 0 Time Series Summary for NY CITY CENTRAL PARK, NY - Month of Sep Click column heading to sort ascending, click again to sort descending. Rank Year Lowest Min Temperature Missing Count 1 1910 57 0 2 2015 56 0 - 1921 56 0 3 2021 54 1 - 2018 54 0 - 2017 54 0 - 2016 54 0 - 2010 54 0 - 2002 54 0 - 1982 54 0 - 1960 54 0 - 1891 54 0 Time Series Summary for LAGUARDIA AIRPORT, NY - Month of Sep Click column heading to sort ascending, click again to sort descending. Rank Year Lowest Min Temperature Missing Count 1 2010 59 0 2 2018 57 0 - 2016 57 0 3 2021 56 1 - 2015 56 0 - 2012 56 0 - 2002 56 0 Time Series Summary for JFK INTERNATIONAL AIRPORT, NY - Month of Sep Click column heading to sort ascending, click again to sort descending. Rank Year Lowest Min Temperature Missing Count 1 2015 56 0 2 2021 54 1 - 2018 54 0 - 2017 54 0 - 2002 54 0 - 1994 54 0 - 1968 54 0 Time Series Summary for IGOR I SIKORSKY MEMORIAL AIRPORT, CT - Month of Sep Click column heading to sort ascending, click again to sort descending. Rank Year Lowest Min Temperature Missing Count 1 2021 52 1 - 2018 52 0 2 2017 50 0 - 2015 50 0 - 2002 50 0 - 1977 50 0

Yeah, the November 2019 record early hard freeze following the October record warmth was a recent example of this. The record low 20s in November following the record mid 90s in October just flattened the late blooming fall plants. So November has been our month that we can still get record cold. Areas to our north that used to get late September freezes like Albany had them pushed back to mid-Ocrober. Since NYC has had the average first freeze November for a long time, the freeze date change isn’t as dramatic. First freeze dates Albany…1951-1980….9-29…..2010-2020….10-16 NYC…….1951-1980….11-11…..2010-2020….11-18

Yeah, the low was 48° at HPN. The first 40s and 30s have been getting later faster than the first freeze. My guess is that this is due to the September and October warming faster than November. So the first freeze date is closer to the colder weather arriving in November during recent years. Then as the warming has picked up in December, the first low below 20° since 2010 got pushed back by 12 days compared to the 1952-1980 climate normals period. HPN average first 40s 2010-2020…..9-20……1952-1980…..9-9 ………………………….30s 2010-2020….10-17…….1952-1980…..10-06 ………………………….32 2010-2020….10-30…….1952-1980…..10-26 ………………………….10s 2010-2020 12-17……..1952-1980…..12-05

Long range ensembles seem to be better at seeing the ridges. It usually takes a while longer for the individual shortwaves that produce the precipitation to show up. But we often see upper lows eventually getting stuck somewhere under strong blocks to our north.

Five of our stations have already reached 50” of precipitation for the year. Data for January 1, 2021 through September 29, 2021 Click column heading to sort ascending, click again to sort descending. State Name Station Type Total Precipitation NJ HARRISON COOP 54.25 NY NY CITY CENTRAL PARK WBAN 51.96 NJ NORTH ARLINGTON 0.7 WNW CoCoRaHS 51.05 NJ RINGWOOD 3.0 SSE CoCoRaHS 50.37 NJ WEST CALDWELL TWP 1.3 NE CoCoRaHS 50.27

September was the third consecutive month with our local stations exceeding 10” of rainfall. Several locations exceeded a 1000 year annual recurrence interval for our older climate with Ida. The office of water prediction keeps a list of these events. Monthly Data for September 2021 for Upton NY NWS CWA Click column heading to sort ascending, click again to sort descending. State Name Station Type Total Precipitation CT RIDGEFIELD 1.9 SSE CoCoRaHS 12.16 CT RIDGEFIELD 3.7 NNE CoCoRaHS 11.94 CT DARIEN 2.4 NW CoCoRaHS 11.82 NJ NORTH ARLINGTON 0.7 WNW CoCoRaHS 11.70 CT DARIEN 3.6 N CoCoRaHS 11.69 NJ HARRISON COOP 11.47 CT NEW CANAAN 1.9 ENE CoCoRaHS 11.13 CT BROOKFIELD 3.3 SSE CoCoRaHS 10.98 CT WILTON 1.9 NW CoCoRaHS 10.98 CT NEW CANAAN 3.8 N CoCoRaHS 10.81 CT DARIEN 1.8 ENE CoCoRaHS 10.68 NY STATEN ISLAND 4.5 SSE CoCoRaHS 10.66 NJ MAPLEWOOD TWP 0.9 SE CoCoRaHS 10.65 CT NORWICH 2.5 NNE CoCoRaHS 10.61 CT BETHEL 3.5 NNE CoCoRaHS 10.58 CT NORWALK 2.9 NNW CoCoRaHS 10.58 NJ NEWARK LIBERTY INTL AP WBAN 10.50 CT WALLINGFORD CENTER 1.9 WNW CoCoRaHS 10.38 NJ KEARNY 1.7 NW CoCoRaHS 10.36 NJ LINDEN 2.2 NW CoCoRaHS 10.16 NJ TENAFLY 1.3 W CoCoRaHS 10.09 NY NY CITY CENTRAL PARK WBAN 10.03 https://www.weather.gov/owp/hdsc_aep

September 29th is the 2nd latest in the fall that HPN has dropped below 50°. It’s currently at 49°. All the top 5 latest dates have been since 2015. Weather Conditions For: White Plains - Westchester County Airport, NY. KHPN 29 Sep 6:56 am 49 First/Last Summary for WESTCHESTER CO AP, 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 2018 06-12 (2018) 49 10-12 (2018) 47 121 2017 06-09 (2017) 47 09-29 (2017) 47 111 2002 06-08 (2002) 48 09-29 (2002) 48 112 1970 05-30 (1970) 44 09-29 (1970) 42 121 1968 05-28 (1968) 46 09-29 (1968) 49 123 2005 05-25 (2005) 46 09-28 (2005) 46 125 2015 06-02 (2015) 48 09-27 (2015) 47 116 1980 06-14 (1980) 47 09-27 (1980) 44 104 2016 05-21 (2016) 48 09-25 (2016) 44 126

Maybe the big ridge over Eastern Canada and the Northeast means that we are finally getting 500 mb patterns that are coupled with the ENSO. This is a textbook La Niña pattern for the month of October. It could be related to the recent PDO drop and cooler SSTs off of the West Coast. 16-17 and 17-18 were are last two winters that the La Niña or any ENSO state fully coupled.

Getting 10” of rain each month from July to September is an impressive feat even in South Florida. Miami still hasn’t been able to pull it off. But several other stations have. Monthly Total Precipitation for MIAMI INTERNATIONAL AP, FL Click column heading to sort ascending, click again to sort descending. Year Jul Aug Sep Season 1941 15.33 5.01 8.01 28.35 1939 13.85 11.34 6.70 31.89 1947 13.51 6.66 10.71 30.88 2002 12.76 6.55 6.48 25.79 2013 12.70 4.43 10.47 27.60 2017 12.45 8.57 14.97 35.99 1946 11.78 5.13 5.24 22.15 1985 11.23 11.88 8.59 31.70 1988 10.90 7.89 3.09 21.88 2019 10.54 15.74 3.25 29.53 2014 10.29 9.07 7.25 26.61 2020 10.26 7.44 10.92 28.62 Monthly Total Precipitation for MIAMI OPA LOCKA AP, FL Click column heading to sort ascending, click again to sort descending. Year Jul Aug Sep Season 2002 13.11 7.10 4.83 25.04 2014 12.97 8.45 8.88 30.30 2017 11.73 14.11 16.70 42.54 2009 11.53 7.87 9.74 29.14 2013 10.91 4.54 8.23 23.68 2004 10.26 10.88 12.60 33.74 Monthly Total Precipitation for MIAMI KENDALL TAMIAMI EXEC AP, FL Click column heading to sort ascending, click again to sort descending. Year Jul Aug Sep Season 2000 14.74 9.46 6.79 30.99 2006 14.16 9.10 6.21 29.47 2013 11.73 3.48 4.12 19.33 2014 10.92 4.82 5.84 21.58 2020 10.53 2.99 7.82 21.34 2001 10.22 8.74 13.52 32.48 2012 10.10 12.78 11.30 34.18 Monthly Total Precipitation for NAPLES MUNICIPAL AIRPORT, FL Click column heading to sort ascending, click again to sort descending. Year Jul Aug Sep Season 2006 12.16 11.60 7.50 31.26 2017 11.24 15.55 18.03 44.82 2015 10.15 2.78 6.75 19.68

Radar indicating some small hail possible with the stronger storms on Long Island. OKX set a new daily mid-level lapse rate record.

Islip adds another 75° day to set the new September record. MacArthur/ISP PTSUNNY 75 61 61 W10 Time Series Summary for ISLIP-LI MACARTHUR AP, NY - Month of Sep Click column heading to sort ascending, click again to sort descending. Rank Year Number of Days Max Temperature >= 75 Missing Count 1 2021 26 2 2 2005 25 0 3 2015 24 0 - 1980 24 0 4 2019 23 0 - 1998 23 0 5 2017 22 0 - 2007 22 0 6 2020 21 0 - 1968 21 0 7 1972 20 0