bluewave

You know it’s a warm pattern when we go above 50 on an E to NE flow in late January.

Yeah, January 1780 was probably the coldest month on record since the settlers arrived. https://books.google.com/books?id=mon_ivVXUY4C&pg=PA60&lpg=PA60&dq=philadelphia+area+weather+book+january+1780&source=bl&ots=uQqtI1kkA1&sig=ACfU3U3Knse60FfcmGIdLevsstiIuJyzDQ&hl=en&ppis=_e&sa=X&ved=2ahUKEwi-lJGx3JznAhWlV98KHe_BDLcQ6AEwCnoECAoQAQ#v=onepage&q=philadelphia area weather book january 1780&f=false

This very strong +EPO has produced the most Niña-like North Pacific SST pattern in years.

NYC is currently the 9th warmest January with a week to go. Time Series Summary for NY CITY CENTRAL PARK, NY - Month of Jan Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 1932 43.2 0 2 1990 41.4 0 - 1950 41.4 0 3 2006 40.9 0 4 1913 40.8 0 5 1937 40.2 0 - 1933 40.2 0 6 1998 40.0 0 7 2002 39.9 0 8 1880 39.2 0 9 2020 39.0 8 10 1949 38.6 0

Continuing right into this month with the long term stuck storm track. Imagine if one of these Great Lakes lows deepens below 975 mb over the region. https://chicago.cbslocal.com/2020/01/11/storm-surge-brings-crashing-waves-flooding-to-lakefront-areas-that-have-already-been-suffering/

No surprise with the record breaking Great Lakes storm track.

It looks like the models are going for forcing in the MJO 6 and 1- 2 regions the next few weeks. So we’ll have to see what that combination looks like in the actual pattern. Plus the +AAM spike gets added to the mix. So a continuation of La Niña and El Niño influences which shows up in the split flow.

You know it’s a warm January when NYC doesn’t drop below 20 and HPN and ISP stay above 15. Time Series Summary for NY CITY CENTRAL PARK, NY - Month of Jan Click column heading to sort ascending, click again to sort descending. Rank Year Lowest Min Temperature Missing Count 1 1937 25 0 2 1990 24 0 - 1932 24 0 3 2002 21 0 - 1993 21 0 - 1953 21 0 4 2020 20 9 - 1949 20 0 Time Series Summary for WESTCHESTER CO AP, NY - Month of Jan Click column heading to sort ascending, click again to sort descending. Rank Year Lowest Min Temperature Missing Count 1 1990 21 1 2 1953 18 0 3 1993 17 2 4 2020 16 12 - 2002 16 0 5 1960 15 0 Time Series Summary for ISLIP-LI MACARTHUR AP, NY - Month of Jan Click column heading to sort ascending, click again to sort descending. Rank Year Lowest Min Temperature Missing Count 1 1990 21 0 2 1993 18 0 3 2020 16 9 4 2002 15 0 - 1998 15 0

Yeah, we may end up needing help from MJO or other factors to get that vortex out of Alaska. This is our first time since the 2006-2012 era that we had such a strong +EPO from December into at last the start of February. The chart below shows how different this is from what we have experienced since 2012. The CPC chart is the inverse of how we typically discuss the EPO. The negative values are what we consider the +EPO. The positive values since 2013 reflect the predominant -EPO over this period. https://www.cpc.ncep.noaa.gov/data/teledoc/ep_ts.shtml

Nice post. It really looks like the MJO 3 in mid-December kicked off this extreme +EPO. Also notice how the record MJO 4-6 in January seemed to reinforce this pattern. Maybe we’ll need a strong enough phase 1 at some point in February to reverse this. But there could be other variables that could maintain the +EPO or change it more negative as move though February.

You are correct. The NWS in Upton never updated their page. But the 25.8 average shows up on the NCDC site. https://www1.ncdc.noaa.gov/pub/orders/IPS/IPS-6EC204A7-8A43-4BEC-90BB-28F70C084E99.pdf

As defined by the 1981-2010 climate normals it is. Averages are based on the 30 year period 1981-2010 https://www.weather.gov/media/okx/Climate/CentralPark/nycnormals.pdf Season 25.8 corrected https://www.ncdc.noaa.gov/data-access/land-based-station-data/land-based-datasets/climate-normals/1981-2010-normals-data What are Climate Normals? In the strictest sense, a "normal" of a particular variable (e.g., temperature) is defined as the 30-year average. For example, the minimum temperature normal in January for a station in Chicago, Illinois, would be computed by taking the average of the 30 January values of monthly averaged minimum temperatures from 1981 to 2010. Each of the 30 monthly values was in turn derived from averaging the daily observations of minimum temperature for the station. In practice, however, much more goes into NCEI's Climate Normals product than simple 30-year averages. Procedures are put in place to deal with missing and suspect data values. In addition, Climate Normals include quantities other than averages such as degree days, probabilities, standard deviations, etc. Climate Normals are a large suite of data products that provide users with many tools to understand typical climate conditions for thousands of locations across the United States. Why does NOAA produce Climate Normals? What are Climate Normals used for? Meteorologists and climatologists regularly use Climate Normals for placing recent climate conditions into a historical context. NOAA's Climate Normals are commonly seen on local weather news segments for comparisons with the day's weather conditions. In addition to weather and climate comparisons, Climate Normals are utilized in seemingly countless applications across a variety of sectors. These include regulation of power companies, energy load forecasting, crop selection and planting times, construction planning, building design, and many others.

NYC will need a KU snowstorm to reach normal seasonal snowfall. NYC 2.9”- 6.5”snowfall by January 24th since 1950 and seasonal total snowfall 2008....2.9....11.9 2002....3.5.....3.5 1952....3.7....19.7 1951....3.8....9.3 1959...4.3....13.0 1997...4.5....10.0 1963....4.7....16.3 2020....4.8......? 1983...4.9.....27.2....KU 2013...5.1.....26.1....KU 1989....5.3....8.1 1980....5.5....12.8 1956....5.5.....33.5....KU 1999....6.5.....12.7

NYC is on track to reach the last week of January with the 5th lowest snowfall since 2000. They are a little below the same time last year. Time Series Summary for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Rank Ending Date Total Snowfall Oct 1 to Jan 24 Missing Count 1 2007-01-24 0.4 0 2 2000-01-24 2.5 0 3 2008-01-24 2.9 0 4 2002-01-24 3.5 0 5 2020-01-24 4.8 4 6 2013-01-24 5.1 0 7 2019-01-24 7.1 0 8 2012-01-24 7.2 0 9 2015-01-24 7.3 0 10 2017-01-24 10.1 0 11 2006-01-24 11.7 0 12 2009-01-24 12.0 0 13 2010-01-24 13.2 0 - 2003-01-24 13.2 0 14 2018-01-24 17.9 0 15 2005-01-24 18.1 0 16 2001-01-24 21.2 1 17 2014-01-24 26.5 0 18 2004-01-24 26.8 0 19 2016-01-24 27.9 0 21 2011-01-24 36.1 0

It will be interesting to see how that forecast works out. Right now it looks like the Pacific is running two opposites at once. Currently have that record Niño-like +AAM rise and the strong ridge building over Hudson Bay. The near record ridge north of Hawaii and +EPO are more Niña-like. This is the strongest January +EPO since the 11-12 La Niña.

Our seasonal snowfall has become more variable since the early 90’s. NYC used to get snowfall close to normal on a regular basis before then. Mid 20’s snowfall seasons in NYC have become few and far between. Snowfall totals of 20 or less and 30 or more are more frequent. 12-13....26.1 08-09....27.6 92-93....24.5 90-91....24.9 86-87....23.1 84-85....24.1 83-84....25.4 82-83....27.2 81-82....24.6 76-77....24.5 73-74....23.5 71-72....22.9 69-70....25.6

Maybe they meant 12”+ snowstorms. It looks like the last one at EWR, NYC,LGA, and JFK was 1-23-16. The most recent event at ISP was 3-22-18.

The departures were even higher to our north and west.

The general public is going to be very happy when they see their heating bill. Only the 10th time that NYC averaged 40 degrees or higher over the last 30 days. Time Series Summary for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Rank Ending Date Mean Avg Temperature Dec 22 to Jan 20 Missing Count 1 2007-01-20 43.0 0 2 1932-01-20 42.6 0 3 1950-01-20 41.6 0 - 1933-01-20 41.6 0 5 1937-01-20 41.4 0 6 2006-01-20 41.0 0 7 2020-01-20 40.8 0 8 1890-01-20 40.4 0 9 2016-01-20 40.3 0 10 1995-01-20 40.1 0

Same here. I won’t believe a pattern change until it shows up inside 7 days. These +EPO /+NAO patterns can be very difficult to dislodge.

That’s really extreme. This experimental forecast that came out in November may be onto something. https://www.pik-potsdam.de/news/press-releases/early-warning-physicists-from-giessen-potsdam-and-tel-aviv-forecast-el-nino-for-2020 Early warning: Physicists from Giessen, Potsdam and Tel Aviv forecast "El Niño" for 2020 04/11/2019 -The serious weather phenomenon "El Niño" could soon occur again in the Pacific region. Researchers at Justus Liebig University Giessen (JLU), the Potsdam Institute for Climate Impact Research (PIK) and Bar-Ilan University in Ramat Gan, Israel, find that there will probably be another "El Niño" by the end of 2020. The prediction models commonly used do not yet see any signs of this. Schematic figure of the pacific. The red rectangle denotes the area where the Oceanic Niño Index (ONI) is measured. The groundbreaking early forecast is based on a novel algorithm developed by the researchers, which is relies on a network analysis of air temperatures in the Pacific region and which correctly predicted the last two "El Niño" events more than a year in advance. Such long-term predictions can, for example, help farmers in Brazil, Australia or India to prepare themselves and adjust their sowing accordingly. A probability of around 80 percent "Conventional methods are unable to make a reliable 'El Niño' forecast more than six months in advance. With our method, we have roughly doubled the previous warning time," stresses JLU physicist Armin Bunde, who initiated the development of the algorithm together with his former PhD student Josef Ludescher. Hans Joachim Schellnhuber, Director Emeritus of PIK, explains: "This clever combination of measured data and mathematics gives us unique insights - and we make these available to the people affected.” He points out that, of course, the prediction method does not offer one hundred percent certainty: "The probability of 'El Niño' coming in 2020 is around 80 percent. But that's pretty significant." Josef Ludescher, who now works at PIK, emphasizes: "We also predicted the absence of another 'El Niño' in 2019 at the end of last year. Only since July have the official forecasts agreed with our forecast." The team is currently expanding the algorithm in order to be able to forecast also the strength and length of the weather phenomenon in the future. Empty fishing nets, torrential rainfall, extended droughts With a conventional early warning period of at most half a year so far, people in the tropics and subtropics are poorly prepared for the often devastating consequences of "El Niño" (Spanish for "the Godly Child") at irregular intervals around Christmas - empty fishing nets and torrential rainfall in Peru as well as extended droughts in parts of South America, Indonesia, Australia and Africa. In addition, the Indian subcontinent may experience a change in monsoon patterns and California may experience more precipitation. For their investigations, the researchers use a network of atmospheric temperature data in the tropical Pacific consisting of 14 grid points in the equatorial "El Niño" core area, and 193 points in the Pacific outside this core area. The physicists had discovered that already in the year before the eruption of an "El Niño", the teleconnection effect between the air temperatures inside and outside of the core area becomes considerably stronger. In particular, they used this effect to optimize their prediction algorithm. The discovery of the new method was first published in summer 2013 in an article in the renowned "Proceedings of the National Academy of Sciences". Reliable data from the period between the beginning of 1950 and the end of 2011 were available to the researchers for the investigations. The period between 1950 and 1980 served them as a learning phase for determining the alarm thresholds. With the help of this algorithm, the "El Niño" events could then be predicted and compared with the actual events. In 80 percent of the cases, the alarm was correct and the "El Niño" event could be accurately predicted the year before. Article: Josef Ludescher, Armin Bunde, Shlomo Havlin, Hans Joachim Schellnhuber (2019): Very early warning signal for El Niño in 2020 with a 4 in 5 likelihood. arXiv:1910.14642 Weblink to the article: https://arxiv.org/abs/1910.14642 Support: This work was supported by the East Africa Peru India Climate Capacities (EPICC) project. This project is part of the International Climate Initiative (IKI). The Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (BMU) supports this initiative on the basis of a decision adopted by the German Bundestag. Please find more information on the project here: https://www.international-climate-initiative.com/en/nc/details/project/climate-capacity-building-risk-anticipation-and-minimization-18_II_149-3007 For further information please contact: PIK press office Phone: +49 331 288 25 07 E-Mail: [email protected] Twitter: @PIK_Climate www.pik-potsdam.de

This is a continuation of the misalignment discussion. Niño-like ridge near Hudson Bay and Niña-like ridge NE of Hawaii. Almost a combination of the 97-98 and 11-12 patterns at 500 mb to close out January.

This looks like the first time since 2010 that the NYC January minimum temperature finishes warmer than December. Monthly Lowest Min Temperature for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Year Dec Jan Season 2019-2020 16 20 16 2018-2019 24 2 2 2017-2018 9 5 5 2016-2017 17 14 14 2015-2016 34 11 11 2014-2015 24 8 8 2013-2014 19 4 4 2012-2013 28 11 11 2011-2012 22 13 13 2010-2011 19 6 6 2009-2010 16 13 13

Historic event for that part of Canada. https://weather.gc.ca/warnings/weathersummaries_e.html#NL Weather summary for Newfoundland issued by Environment Canada at 3:00 p.m. NST Sunday 19 January 2020. Discussion. A powerful January storm brought intense winds and record-breaking snowfall to parts of Newfoundland on Friday into Friday night. A new all-time daily snowfall record was established at St. John's International Airport. New record: 76.2 cm (January 17, 2020). Previous daily record: 68.4 cm (April 5, 1999). Records began in 1942. The above total is applicable for the January 17 climatological day, which is a 24 hour period ending at 2:30 A.M. NST on January 18. An additional 2.0 cm was recorded after 2:30 A.M. The area of low pressure responsible for the snow and wind emerged from the northeastern United States early Thursday and began to rapidly intensify as it moved over the Gulf of Maine. The system deepened into a powerful storm as it tracked southeast of the Avalon Peninsula on Friday, before departing into the North Atlantic early Saturday. The storm battered the eastern half of the island with heavy snowfall, extremely high winds and damaging coastal storm surge. The following is a summary of information received by Environment and Climate Change Canada as of 2:30 P.M. NST Sunday. Total snowfall (in centimetres): Mount Pearl: 93 Paradise: 91 St. John's East: 82 St. John's International Airport: 78 Mount Carmel: 61 Lethbridge: 48 Gander International Airport: 35 Gander West: 35 St. Lawrence: 31 Grand Falls-Windsor: 10 Maximum wind gusts (in kilometres per hour): Green Island, Fortune Bay: 171 Bonavista: 164 Grates Cove: 156 Heart's Delight-Islington: 156 Cape Pine: 146 Green Island, Trinity Bay: 145 Twillingate: 140 St. John's - Doheney Place: 134 St. John's - East White Hills: 132 St-Pierre: 130 St. John's - Dockyard: 129 Pass Island: 126 Allan's Island: 116 Holyrood: 114 Bishop's Cove: 113 Ramea: 109 St. Lawrence: 106 Burgeo: 105 St. John's West: 105 Deer Park: 101 North Harbour: 101 Gander: 97 At St. John's International Airport the official wind sensor malfunctioned during the storm. Reported winds were estimated to be between 65 and 85 knots (120 to 157 km/h). However, it will likely not be possible to provide a verified maximum gust. The wind sensor at Gander International Airport also briefly malfunctioned. The highest gust at the nearby Gander climate station was measured as reaching 97 km/h. The following area set a daily minimum temperature record on January 18, 2020: Winterland Area (Winterland Branch Hill) New record of -17.9 Old record of -17.8 set in 2001 Records in this area have been kept since 1970 Note: the temperature record reported here has been derived from a selection of historical stations in this geographic area that were active during the period of record. Please note that this summary may contain preliminary or unofficial information and does not constitute a complete or final report. End/NLWO