bluewave

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.

Here are the probabilities of NYC getting a 6” warning snowfall in a December -EPO and +NAO pattern. SWFE............................Medium Benchmark KU.............Low IVT Nurlon....................Low Anafrontal....................Low

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. All the guidance continues this pattern until further notice. So the -EPO and +NAO may turn out to be the dominant December pattern.

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.

Look on the bright side. At least the heavy rain potential next week will wash away all the leftover salt on the paved surfaces. But make sure you have rain gutters with leaf guards.

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.

It’s only a Miller A front end thump if the high can hold on long enough. But a more amped solution like the Euro won’t work out. A few days ago the models looked more SWFEish. But now models have a more amplified system. I agree that we need a weaker wave to be more of a SWFE. Especially with the NAO and AO making another big positive spike. A -EPO can only do so much on its own.

The timing of that Arctic high will mean everything for the correct SWFE front end thump potential in mid-December. Need the high to hold on longer like the GFS has. The Euro scooting the high east faster wouldn’t work out.

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.

Getting a more favorable Pacific with the -EPO. But the amplified systems cut with the +AO/+NAO. This produces an Arctic shot for 3 days before the next cutter warms us back up. The one thing that could work in this pattern would be a well timed SWFE.