bluewave

Looks like the new shortest duration between 2 different seasonal T’s. May 9th to October 30th.

Yeah, the 5th coldest October minimum temperature on record for NYC. Time Series Summary for NY CITY CENTRAL PARK, NY - Month of Oct Click column heading to sort ascending, click again to sort descending. Rank Year Lowest Min Temperature Missing Count 1 1936 28 0 2 1976 29 0 - 1925 29 0 - 1887 29 0 - 1879 29 0 3 1940 30 0 - 1869 30 0 4 1988 31 0 - 1975 31 0 - 1974 31 0 - 1969 31 0 - 1871 31 0 5 1972 32 0 - 1965 32 0 - 1933 32 0 - 1928 32 0 - 1917 32 0 - 1904 32 0 - 1889 32 0 - 1876 32 1 2020 32 0

No surprise that we are seeing another very early season snow with the North American snow cover extent setting a new October record. This is our 5th snow event by mid-November since 2008. This includes the late October events in 2008 and 2011 along with November 2012 and 2018. Let me know if I am missing one from the northern parts of our forum. My guess is that this is related to the steep October sea ice decline since 2007. https://www.star.nesdis.noaa.gov/smcd/emb/snow/HTML/snow_extent_plots.html

Yeah, Saturday morning may be our lowest temperature for a while. The early next week cool down not looking as impressive. Then we get a moderation in temperatures.

While the record cold around the Rockies and Plains has been impressive, it’s focused over a very small geographic region of the planet. The coverage of the record cold is much smaller than the areas and magnitude of record warmth as the world warms. It’s no coincidence that the record October cold near Montana is occurring in an isolated pocket relative to the overall extent of the global temperature increases. Montana represents a portion of the only 17 out of 2,844 stations with under 6 months of warming over the last 30 years.

If NYC can drop to 34° or lower before the end of October, then it would be the first time since 2011. ..New York City... Central Park, NY Rain Rain Sunny Ptcldy Ptcldy Ptcldy Sunny /52 44/45 34/49 41/58 39/48 36/51 40/58 /100 100/80 10/00 00/30 30/10 00/00 00/10 Time Series Summary for NY CITY CENTRAL PARK, NY - Month of Oct Click column heading to sort ascending, click again to sort descending. Year Lowest Min Temperature Missing Count 2019 43 0 2018 38 0 2017 42 0 2016 38 0 2015 35 0 2014 42 0 2013 40 0 2012 38 0 2011 33 0

This was the October version of DJF 17-18.

Much warmer SSTs this October than in 1995. The Western Ridge is also significantly stronger. You can see how much more amplified the 500 MB pattern is this year.

Notice how the seasonal forecasts from August missed the magnitude of the Ridge parked over Western North America this fall. UKMET Euro September and October verification

Yeah, the ridge locked in near the West Coast keeps warming the SSTs. So we got the smallest north-south SST gradient in the NE Pacific. These are the warmest NE Pacific SSTs we have seen with a La Niña of this strength.

Maybe it’s related to the record WPAC warm pool? I read some papers on how the anomalous ridging near the West Coast since 2013 could be related to the record SSTs in the Tropical WPAC. Then there were other papers that suggest a link between the record Pacific basin SSTs and the low Arctic sea ice.

Yeah, the PNA is also more positive than we typically see during a La Niña September and October. That big drought ridge over the West continues to make headlines. You can see that the ridge in that location doesn’t really match La Ninas in the last 20 years.

Yeah, looks like the vortex will verify over Greenland instead of Alaska. New run Old run

Yeah, we get 2 decent cold shots before the big NAO reversal and moderating temperatures.

Cloudiness is running well above average for October like recent years. https://mesonet.agron.iastate.edu/plotting/auto/?_wait=no&q=45&network=NY_ASOS&zstation=LGA&hour=12&year=2020&month=10&dpi=100&_fmt=png

May 1977 was the last time.

A very early first flakes of the season would match our recent years experience. 2017-2018, 2018-2019, and 2019-2020 were all defined by the snowfall which occurred outside DJF met winter. The most impressive snowfall records were in the fall and spring. March and April 2018 Time Series Summary for ISLIP-LI MACARTHUR AP, NY - Month of Mar Click column heading to sort ascending, click again to sort descending. Rank Year Total Snowfall Missing Count 1 2018 31.9 0 2 1967 23.3 1 3 2015 19.7 0 Time Series Summary for ISLIP-LI MACARTHUR AP, NY - Month of Apr Click column heading to sort ascending, click again to sort descending. Rank Year Total Snowfall Missing Count 1 1982 16.0 0 2 1996 9.6 0 3 2018 4.6 0 November 2018 Time Series Summary for NY CITY CENTRAL PARK, NY - Month of Nov Click column heading to sort ascending, click again to sort descending. Rank Year Total Snowfall Missing Count 1 1898 19.0 0 2 1882 14.0 0 3 1938 12.8 0 4 2018 6.4 0 March 2019 Time Series Summary for IGOR I SIKORSKY MEMORIAL AIRPORT, CT - Month of Mar Click column heading to sort ascending, click again to sort descending. Rank Year Total Snowfall Missing Count 1 1967 21.8 0 2 1956 19.4 0 3 2015 18.6 0 - 2001 18.6 0 4 2005 18.5 0 5 2018 14.5 0 6 1993 13.7 0 7 2019 13.5 0 May 2020 Time Series Summary for NY CITY CENTRAL PARK, NY - Month of May Click column heading to sort ascending, click again to sort descending. Rank Year Total Snowfall Missing Count 1 2020 T 0 - 1995 T 0 - 1977 T 0 - 1956 T 0 - 1946 T 0

It would be the shortest duration between a T at the end of a snowfall season and T the beginning of the next. Getting a T on May 9th and also in late October in the same year would be a new record. So it will be interesting to see if could at least see a T with the storm.

Montana is one of the few spots able to set notable cold records.

October has been the most reliably negative AO month of the last 20 years.

While the US has become used to record October snowfalls in this low sea ice era, this year is in a class by itself. Seems to have started right around 2006 with the historic early Buffalo October LES Snowstorm. Then NNJ had the record early snows at the end of October 2008. Followed by the NYC record early snowstorm at the end of October 2011. There have been numerous record early October shows since then mainly across the Rockies and Midwest like this year so far. https://www.star.nesdis.noaa.gov/smcd/emb/snow/HTML/snow_extent_plots.html

The Euro finally came north with the heavy rain potential from Zeta later in the week.This is followed by possibly the first 30s of the season for NYC around the end of the month. Then temperatures quickly warm across the US to start November.

Meteostar http://wxweb.meteostar.com/meteogram/link.shtml?choice=KSYR I just saw them. The control and other members are more amped than the OP. Even if the low ends up hugging, it would be nice to see see a southern stream low phase or not get suppressed.