bluewave

It would be nice to get back to the benchmark KU snowstorm pattern that ran up through March 2018. While small or moderate snows are OK, they can’t compare with high end events.This recent pattern has been more like something from the 80’s into the early 90’s. You learn to appreciate whatever snows you can get.

We generally need a high impact event like a rapidly deepening low to pull it off. It also helps to be closer to a climatologically colder and snowier part of the winter. Under these circumstances we can go from 60 degrees to a 12”+. https://www.weather.gov/okx/Blizzard_Feb92017

Piece of cake with a low bombing out near the benchmark in the heart of winter like 2-9-17.

I guess it comes down to the biggest snows in NYC usually sharing the wealth with the wider area. One exception was February 2006 which wasn’t as good in some spots. But the best snows in NYC generally mean many surrounding areas do very well. January 2016 was a great example of this.

The Euro has 3.8” as frozen including mixed for NYC. It starts at 38 and ends at 32. So cut that in half for cold surface accusation to around 2”. The coating is if later runs decrease the precipitation and it’s a little warmer. The 3 could be some colder spots like the North Shore of Long Island with a heavier snow burst and the temp falling to 31.

You know that people are hungry for snow after last winter. If a coating to 3 mainly on colder surfaces potential causes all this bickering, then better hope the KU snow machine cranks up before the winter is over. I can’t even imagine what this place would have been like from 96-97 to 01-02. Or even 79-80 to 91-92 for that matter.

The timing for any potential weakening of the -EPO may begin just before the solstice. We have seen this temperature moderation period often during the last decade. Even the MJO remaining in the weaker circle portion of phases 4-5 could produce a temperature moderation. Not really speculating on what things look like all the way out to January yet.

Longer range, it looks like convection migrating toward the Maritime Continent may weaken the -EPO. We’ll see how it goes. EPO forecast courtesy of Bamwx on twitter from weathermodels.com

Easily the snowiest first week of December on record for Albany. Time Series Summary for Albany Area, NY (ThreadEx) Click column heading to sort ascending, click again to sort descending. Rank Ending Date Total Snowfall Dec 1 to Dec 7 Missing Count 1 2019-12-07 24.5 1 2 2003-12-07 19.2 0 3 1977-12-07 12.4 0 4 1902-12-07 10.3 0 5 1926-12-07 10.2 0 6 1901-12-07 10.0 0

Portions of the area could see a 40 degree drop in temperatures from late Tuesday into early Thursday. A 42 degree drop in 36 hours for Newark is the December record set in 1990. https://mesonet.agron.iastate.edu/plotting/auto/?_wait=no&q=169&network=NJ_ASOS&zstation=EWR&hours=36&month=dec&dir=cool&dpi=100&_fmt=png

The EPS has been too warm while the GEFS has been too cold. But these biases can change in the future. https://www.frontierweather.com/verification.html

I will look on the positive side. That November snow prevented parts of the area from finishing the season in the single digits. Monthly Total Snowfall for ISLIP-LI MACARTHUR AP, NY Click column heading to sort ascending, click again to sort descending. Year Oct Nov Dec Jan Feb Mar Apr Season 2018-2019 0.0 4.3 T 0.9 3.5 4.1 T 12.8

The rapid warming of the NW Atlantic independent of the AMO may be an even bigger story for all the extreme coastal storms we continue to see. https://phys.org/news/2016-01-northwest-atlantic-ocean-warmer-sooner.html

Yeah, small 1-2 inch events like the other day are nice. But we need the help of multiple warning level snow events for a normal to above normal snowfall season.

December 2013 was a +NAO and -EPO pattern also. My guess is that the warming WPAC is giving us this low frequency forcing pattern. We got a lucky SFWE on 12-13-14. So NYC finished with above normal snowfall in December. But the MJO going into 4-5 spoiled the party with the 70 degree temperatures around the solstice. That was the only reason NYC finished +1 instead of a cold departure. So root for the MJO to stay weak the rest of the month with a lucky SWFE.

I know everyone likes to look at the MJO RMM charts. But sometimes the low frequency forcing can tell the story. Notice the persistent low frequency forcing since the beginning of November over the WPAC. It lines up with a MJO 6 pattern this time of year. You can see this is the December pattern so far with the -EPO and +NAO.

While it has been a cold pattern, the storm tracks have been too warm for much snow at the coast. Looks like we see a continuation of this next week. A few days of warm and wet followed by more cold and dry. NYC is actually behind the snowfall pace of last year. NYC has 1.6”vs 6.4” by December 6th last year.

40 and flurries in SW Suffolk.

The record amount of open water for the Chukchi Sea continues to be one of the big stories this year.

Yeah, the interior Northeast is doing great in this pattern. Must be nice living on an area where the phase of the NAO and AO aren’t as important as the coast for record snows.

None of the models have shown much skill day 11-15 last few weeks. But this -EPO +NAO pattern has been a familiar one in December since 2013. One of the main characteristics has been big temperature swings. Where we alternate between +10’s departure days or higher and -10’s or lower.

Classic December -EPO +NAO pattern. This sets up a duel between the the -EPO ridge and the SE ridge. So we get alternating warm ups and cool downs. Amplified systems cut to the Great Lakes in this pattern. Root for a perfectly timed SWFE if you want to get a nice front end thump.

NYC has done better this decade with snow in November than during the first week of December.This is a big reversal from last decade. Time Series Summary for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Ending Date Total Snowfall Dec 1 to Dec 7 Missing Count 2019-12-07 1.6 4 2018-12-07 0.0 0 2017-12-07 0.0 0 2016-12-07 0.0 0 2015-12-07 0.0 0 2014-12-07 0.0 0 2013-12-07 T 0 2012-12-07 0.0 0 2011-12-07 0.0 0 2010-12-07 T 0 Time Series Summary for NY CITY CENTRAL PARK, NY - Month of Nov Click column heading to sort ascending, click again to sort descending. Year Total Snowfall Missing Count 2019 0.0 1 2018 6.4 0 2017 T 0 2016 T 0 2015 0.0 0 2014 0.2 0 2013 T 0 2012 4.7 0 2011 0.0 0 2010 T 0 Time Series Summary for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Ending Date Total Snowfall Dec 1 to Dec 7 Missing Count 2009-12-07 T 0 2008-12-07 T 0 2007-12-07 1.7 0 2006-12-07 0.0 0 2005-12-07 3.5 0 2004-12-07 0.0 0 2003-12-07 14.0 0 2002-12-07 6.0 0 2001-12-07 0.0 0 2000-12-07 0.0 0 Time Series Summary for NY CITY CENTRAL PARK, NY - Month of Nov Click column heading to sort ascending, click again to sort descending. Year Total Snowfall Missing Count 2009 0.0 0 2008 T 0 2007 T 0 2006 0.0 0 2005 T 0 2004 T 0 2003 0.0 0 2002 T 0 2001 0.0 0 2000 0.0 0

This looks like our first decade with the December AO reaching +3 or higher during 5 years. Ridiculous reversal following the record lows in December 2009 and 2010. Something really changed with the December AO and NAO after 2010. Years with AO reaching +3 or higher in December 2019 2016 2015 2013 2011

Battle of many competing influences coming up. Big East Asian Jet extension meets the -EPO. So the have a very fast split flow with an up and down temperature pattern. The question this month will be what happens with the MJO. All the models agree that it is headed for MJO 2. Longer range MJO forecasts are always poor. But every case of a MJO 2 in December since 1975 was followed by a move into phases 4-6. The only difference was the variation in amplitude of those phases. Big temperature swings coming up