bluewave

I guess it isn’t a surprise that December is the fastest warming winter month around the area. It’s like the seasons are getting pushed back. Summer into fall and fall into December. It was another top 5 or top 10 warmest fall for a large part of the country.

With the recent model runs correcting warmer for December, areas around NYC may be on track for another 40° or warmer December. A 40° December used to be a rarity before recent times. Now they are occurring more frequently.

The first two days of December are verifying warmer than model forecasts. We are currently in the 50s for early in the morning. The model error with the fast Pacific flow and record Atlantic SSTs is too cool. Regional Weather Roundup National Weather Service New York NY 600 AM EST THU DEC 02 2021 Note: "FAIR" indicates few or no clouds below 12,000 feet with no significant weather and/or obstructions to visibility. NYZ071-072-176-178-NJZ106-104-021200- New York City Metro Area CITY SKY/WX TMP DP RH WIND PRES REMARKS Central Park CLOUDY 52 47 83 VRB3 29.91F World Trd Ctr NOT AVBL Bronx Lehman C N/A 52 46 82 S6 N/A LaGuardia Arpt CLOUDY 52 46 80 S9 29.88F Queens College N/A 52 48 87 S13 N/A Kennedy Intl MOCLDY 52 48 86 S14 29.90F Breezy Point N/A 52 N/A N/A S12 N/A Brooklyn Coll N/A 52 48 87 S10 N/A Staten Island N/A 50 46 87 S9 N/A Newark/Liberty CLOUDY 50 46 86 S6 29.89F Teterboro DRIZZLE 49 46 90 SW5 29.88F $$ NYZ177-179-078>081-021200- Long Island New York CITY SKY/WX TMP DP RH WIND PRES REMARKS Jones Beach N/A 54 N/A N/A S13G18 N/A Wantagh N/A 54 50 87 S10 N/A Hempstead NOT AVBL Matinecock Pt N/A 50 N/A N/A S5 N/A Farmingdale PTCLDY 51 46 83 S12 29.90F MacArthur/ISP MOCLDY 51 45 79 SE12 29.89F Stony Brook N/A 50 45 81 S7 N/A Shirley PTCLDY 51 43 74 SE15 29.91F Mt Sinai Harb N/A 50 N/A N/A S10 N/A Westhampton PTCLDY 52 44 74 SE10G18 29.92F East Hampton CLOUDY 51 43 73 S12 29.92F Southold N/A 50 45 81 S13 N/A Montauk N/A 51 44 77 S7 29.95F

I think that this wave break may be having a bigger influence. It eventually pumps the Aleutians Ridge. Then the -PNA trough digs into the Pacific Northwest boosting the Southeast Ridge during the 2nd week of December.

The Central Park leaves that were blocking the ASOS may have finally begun to drop. It’s near 50° now like JFK and LGA. All the stations are warmer than high temperature guidance today. 000 SXUS51 KOKX 011757 OSOOKX New York City Metropolitan Area Weather Roundup National Weather Service New York NY 100 PM EST WED DEC 01 2021 CITY SKY/WX TMP DP RH WIND PRES REMARKS Central Park MOSUNNY 49 24 37 VRB5 30.16F LaGuardia Arpt PTSUNNY 49 23 36 NW12 30.14F Kennedy Intl PTSUNNY 49 25 39 W14 30.16F

Those record warm Atlantic SSTs and the faster Pacific Jet allowed the ridge over our area to verify stronger than forecast today. Verification already 50° at Newark Old forecast was colder for today Record warm Atlantic SSTs https://mco.umaine.edu/gom_sst/

We have gotten used to the +PDO La Niña Decembers of recent years. But the December La Niña composite with a strong -PDO features a strong Aleutians Ridge like the models are advertising. This creates more of +EPO and -PNA pattern in December. The near record warm Atlantic SSTs will enhance the Southeast Ridge by mid-December.

Multiple 5 sigma North Pacific and East Asian Jet maxes is as extreme as it gets to start December. This really pumps the ridge out near the Dateline and Aleutians. So it keeps reinforcing the +EPO -PNA pattern. The Atlantic is of no help at this time with a strong +AO +NAO pattern.

Several stations across the region has their warmest fall on record. Nearly all finished in the top 10 warmest. This record fall warmth has been a common theme in recent years. Time Series Summary for SUSSEX AIRPORT, NJ Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 2021 54.9 0 2 2011 54.3 6 3 2017 54.2 0 4 2015 54.1 0 5 2020 53.8 0 Time Series Summary for CALDWELL ESSEX COUNTY AP, NJ Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 2021 59.5 3 2 2020 58.4 0 3 2015 58.0 0 4 2016 57.6 0 5 2017 57.2 0 Time Series Summary for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 2021 61.3 0 2 2015 60.9 0 3 1971 60.4 0 - 1961 60.4 0 4 2017 60.3 0 - 1990 60.3 0 5 2016 60.1 0 - 2011 60.1 0 Time Series Summary for FARMINGDALE REPUBLIC AP, NY Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 2015 59.8 0 2 2021 59.2 0 3 2016 59.0 7 4 2020 58.9 2 - 2017 58.9 0 - 2005 58.9 1 5 2011 58.0 0 Time Series Summary for ISLIP-LI MACARTHUR AP, NY Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 2017 58.8 0 2 2015 58.6 0 3 2021 58.5 0 - 2011 58.5 0 4 1990 58.1 0 5 2016 58.0 0 6 2020 57.7 0 - 2005 57.7 0 Time Series Summary for LAGUARDIA AIRPORT, NY Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 2016 62.5 0 2 2021 62.1 0 3 2015 61.9 0 - 2007 61.9 0 - 2005 61.9 0 4 2020 61.8 0 5 2017 61.7 0 Time Series Summary for JFK INTERNATIONAL AIRPORT, NY Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 2015 61.1 0 2 1971 60.8 0 3 2016 60.2 0 4 2021 60.0 0 - 2017 60.0 0 5 1983 59.8 0 - 1961 59.8 0 6 2011 59.5 0 7 2005 59.4 0 8 2020 59.2 0 - 1985 59.2 0 9 1990 59.1 0 10 2010 59.0 0 - 2007 59.0 0 - 1970 59.0 0 Time Series Summary for IGOR I SIKORSKY MEMORIAL AIRPORT, CT Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 2016 59.1 0 2 2011 59.0 0 3 2015 58.9 0 4 2017 58.8 0 5 1973 58.6 0 6 2021 58.4 0 7 2020 58.3 0 8 1977 58.2 0 9 1975 57.9 0 10 2007 57.8 0 Time Series Summary for Boston Area, MA (ThreadEx) Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 2011 58.4 0 2 1931 58.3 0 3 2021 58.1 0 4 1975 57.7 0 5 1927 57.5 0 6 2017 57.4 0 - 1946 57.4 0 7 2015 57.3 0 - 1983 57.3 0 8 1990 57.1 0 9 1953 57.0 0 10 1971 56.9 0 - 1961 56.9 0 Time Series Summary for Caribou Area, ME (ThreadEx) Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 2011 47.8 0 2 2017 47.7 0 3 2021 47.5 0 4 2016 47.3 0 5 1961 46.7 0 6 2001 46.4 0 7 2015 46.2 0 8 2020 45.8 0 9 1999 45.6 0 10 1970 45.3 0 - 1957 45.3 0

It’s ridiculous how extreme the Pacific Jet that’s driving this pattern has become.

The EPS weeklies first started showing this pattern for mid-December back on November 11th.

Classic -PDO pattern showing up now for mid-December. Mild +EPO and -PNA with a +AO/+NAO. This is why we’ll need blocking down the line to push back against such an unfavorable Pacific.

It’s tough to generalize about ENSO sequences during the winter. Last winter was more like an El Niño than a La Niña. Something happened in the late summer this year which lead to the supercharged fall +EPO vortex. That’s what caused the record -PDO drop. So the Pacific Jet is setting records more than we would typically see from just a La Niña alone. This is pretty much the opposite of the 13-14 and 14-15 record NE Pacific warm blob and +PDO/+NPM. Those record warm SSTs were driven by the record -EPO blocking. So the North Pacific has experienced unprecedented volatility in a single decade. Expressions of ENSO states have often been influenced and altered by these extreme pattern swings. Past analogs don’t really do what has been happening over the last decade justice.

The December long range forecasts were looking more interesting at the start of December last year.

Yeah, just going a few miles from the water in weak CAA patterns makes a big difference. This month has been very dry with light winds at night. So the areas away from the direct influence of SSTs still in the 50s were able to radiate. Islip had warmer high temperatures this month and cooler lows. Novembers with true Arctic outbreaks like we had a few years ago usually have colder highs and lows. ISP NOV Max…+0.8 Min….-2.3

It’s representative of all our local stations on the water. The SSTs have been running very warm. Plus the CAA hasn’t been very impressive this month due to the strong Pacific influence. Stations right on the water bolded Regional Weather Roundup National Weather Service New York NY 700 AM EST TUE NOV 30 2021 Note: "FAIR" indicates few or no clouds below 12,000 feet with no significant weather and/or obstructions to visibility. NYZ071-072-176-178-NJZ106-104-301300- New York City Metro Area CITY SKY/WX TMP DP RH WIND PRES REMARKS Central Park CLOUDY 34 21 59 CALM 30.04S World Trd Ctr NOT AVBL Bronx Lehman C N/A 34 23 64 W3 N/A LaGuardia Arpt MOCLDY 35 20 54 CALM 30.03S Queens College N/A 34 23 64 S2 N/A Kennedy Intl MOCLDY 31 24 75 SW5 30.05R WCI 26 Breezy Point N/A 36 N/A N/A W6 N/A WCI 31 Brooklyn Coll N/A 34 25 69 S5 N/A WCI 30 Staten Island N/A 32 25 74 S3 N/A Newark/Liberty MOCLDY 32 23 69 SW5 30.03S WCI 27 Teterboro CLOUDY 29 22 75 CALM 30.02S $$ NYZ177-179-078>081-301300- Long Island New York CITY SKY/WX TMP DP RH WIND PRES REMARKS Jones Beach N/A 34 N/A N/A W5 N/A WCI 30 Wantagh N/A 30 23 74 SW3 N/A Hempstead NOT AVBL Matinecock Pt N/A 36 N/A N/A SW8 N/A WCI 29 Farmingdale PTCLDY 29 20 69 CALM 30.04R MacArthur/ISP PTCLDY 24 19 81 SW3 30.03R Stony Brook N/A 30 25 80 SW2 N/A Shirley PTCLDY 23 18 81 CALM 30.03R Mt Sinai Harb N/A 32 N/A N/A SW2 N/A Westhampton PTCLDY 16 12 84 CALM 30.04R East Hampton FAIR 28 20 70 CALM 30.02R Southold N/A 32 25 74 NW5 N/A WCI 27 Montauk N/A 33 22 63 NW12G20 30.02R WCI 24

The good news is that expectations were lowered when we saw the record -PDO drop this fall. The discussion was about needing impressive Atlantic blocking to counter the record Pacific Jet. Since December has been one of the more +AO + NAO winter months over the last decade, the biggest winter snows have usually occurred later on. NYC in La Ninas generally requires 3” or more of snow in December for normal to above normal seasonal snowfall since the 1990s. But if we don’t make that number in December, a well placed block in JFM can still produce a nice snowstorm.

Another top 5 warmest fall from the Mid-Atlantic to New England.

You can see why all the long range models eventually flatten the MJO 6 ridge out West. It’s another case of the MJO weakening around phase 6 like recent years. So the mid portion of a December will probably see warmer departures than the early part of the month. Bias corrected GEFS and ECMWF

Top 10 driest November as the fast Pacific flow didn’t let many storms amplify. Time Series Summary for LAGUARDIA AIRPORT, NY - Month of Nov Click column heading to sort ascending, click again to sort descending. Rank Year Total Precipitation Missing Count 1 1976 0.31 0 2 2021 0.81 1 3 2001 0.91 0 4 1974 1.01 0 5 1949 1.03 0 6 1965 1.29 0 7 2012 1.35 0 8 1993 1.37 0 9 2009 1.40 0 10 1998 1.48 0 Time Series Summary for NEWARK LIBERTY INTL AP, NJ - Month of Nov Click column heading to sort ascending, click again to sort descending. Rank Year Total Precipitation Missing Count 1 1931 0.37 0 2 1976 0.51 0 3 1933 0.70 0 4 1974 0.80 0 5 2001 0.81 0 6 1998 0.86 0 7 2021 0.88 1 8 1936 0.94 0 9 1934 1.12 0 10 1949 1.15 0 Time Series Summary for WESTCHESTER CO AP, NY - Month of Nov Click column heading to sort ascending, click again to sort descending. Rank Year Total Precipitation Missing Count 1 1976 0.26 0 2 2009 0.61 0 3 1949 0.84 0 4 2012 1.01 0 5 2021 1.11 1 6 2001 1.23 0 7 2017 1.44 2 8 1964 1.69 0 9 2019 1.96 0 - 1993 1.96 0 10 2008 2.01 0 Time Series Summary for JFK INTERNATIONAL AIRPORT, NY - Month of Nov Click column heading to sort ascending, click again to sort descending. Rank Year Total Precipitation Missing Count 1 1976 0.32 0 2 2001 0.61 0 3 2021 0.67 1 4 1993 0.88 0 5 1974 1.10 0 6 1998 1.13 0 7 2015 1.20 0 8 1949 1.30 0 9 1965 1.36 0 10 2009 1.41 0 - 1973 1.41 0 Time Series Summary for ISLIP-LI MACARTHUR AP, NY - Month of Nov Click column heading to sort ascending, click again to sort descending. Rank Year Total Precipitation Missing Count 1 1976 0.39 0 2 2001 0.63 0 3 2021 0.71 1 4 1965 1.08 0 5 1991 1.27 0 6 1990 1.57 0 7 1998 1.64 0 - 1974 1.64 0 - 1964 1.64 0 8 1984 1.69 0 9 2019 1.81 0 10 2012 1.91 0

We have seen high temperatures reach 55+ every year since 2011 between the 18th and 25th. This warm up approaching the holidays has happened in every ENSO state from La Niña to El Niño. Time Series Summary for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Ending Date Highest Max Temperature Dec 18 to Dec 25 Missing Count 2020-12-25 62 0 2019-12-25 57 0 2018-12-25 61 0 2017-12-25 57 0 2016-12-25 59 0 2015-12-25 71 0 2014-12-25 64 0 2013-12-25 71 0 2012-12-25 57 0 2011-12-25 62 0

They made the decision in the 90s when the office moved to OKX to accept the less accurate readings from Central Park. 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.

It was regularly getting stolen in the 1970s. Also notice how they mention that Central Park was warmer than LGA during the summer in the 1970s when the equipment was out in the open. Now it’s hidden underneath the trees and people can’t see it. So while it’s bad for accuracy, at least they don’t have to worry about it getting stolen or vandalized anymore. 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.”

Before the Central Park thermometer was located under the trees, it used to have similar high temperatures to EWR and LGA during heatwaves. This shows open areas of the park outside of deep shade are much closer to LGA and EWR than people realize. The big 1970s heatwaves are a great example of this. 1970s heatwaves in NYC before the trees were similar or warmer at times than EWR and LGA Data for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Date Max Temperature Min Temperature 1973-08-28 98 77 1973-08-29 95 76 1973-08-30 98 78 1973-08-31 94 74 1973-09-01 95 72 1973-09-02 94 74 1973-09-03 96 75 1973-09-04 93 74 Data for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Date Max Temperature Min Temperature 1973-08-28 100 79 1973-08-29 96 79 1973-08-30 98 79 1973-08-31 97 78 1973-09-01 95 75 1973-09-02 95 77 1973-09-03 94 79 1973-09-04 95 75 Data for LAGUARDIA AIRPORT, NY Click column heading to sort ascending, click again to sort descending. Date Max Temperature Min Temperature 1973-08-28 97 78 1973-08-29 94 77 1973-08-30 96 81 1973-08-31 94 75 1973-09-01 91 73 1973-09-02 92 75 1973-09-03 93 75 1973-09-04 93 75 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 Data for LAGUARDIA AIRPORT, NY Click column heading to sort ascending, click again to sort descending. Date Max Temperature Min Temperature 1977-07-13 92 72 1977-07-14 89 72 1977-07-15 90 69 1977-07-16 96 72 1977-07-17 95 74 1977-07-18 95 76 1977-07-19 99 75 1977-07-20 90 74 1977-07-21 99 78

It’s exactly the type of fast Pacific Jet pattern across the US that we get this time of year with no blocking and a strong -PDO.