bluewave

Boxing Day jackpotted west of NYC since it tracked west of the benchmark and brushed Cape Cod. https://www.weather.gov/okx/Meteorology12262010

Excellent article. Thanks very much for posting. The AIFS single was really amplified with this system since later last weekend. I like that it corrects the OP Euro and ensembles suppression tendency we have often seen since the Euro upgrade around 2015 with coastal storms along the East Coast. Open Snow also put out the best seasonal long range winter forecast that I have seen for this winter back in November. Although the write-up didn’t mention it, wonder if they have an experimental in house AI seasonal forecast tool which they didn’t want to mention yet? https://opensnow.com/news/post/november-update-2025-2026-winter-forecast-preview Skilful global seasonal predictions from a machine learning weather model trained on reanalysis data https://www.nature.com/articles/s41612-025-01198-3

Yeah, the Euro AI single meets in the middle between the GFS and other guidance. Has the 2” liquid line from MTP to Ocean county NJ. If that verified exactly, then we could see one primary band further west from Monmouth out into Suffolk. So with the great lifting someone could potentially go 18”+. Would like to see the other guidance come on board by 12z tomorrow to have confidence that some areas could reach those totals. But we don’t have to know for sure until the 12z runs tomorrow.

That’s what everyone want’s to see starting at 0z. Since the NAM is still outside its best under 48 hr range and it hasn’t had an update since 2017. Plus the OP GFS is still more amped and further west than the other operational guidance. But I can see a meet in the middle scenario where we come in under than the OP GFS snowfall totals but higher than some of the other operational runs. We should have a good idea after the 0z to 12z guidance. Sometimes the max banding potential can sneak a little more west than the average of the guidance.

The Canadian Ensemble mean also has 12”+ potential getting closer to NYC.

Even the AI GFS is further east than the OP with a slightly slower capture and negative tilt.

I believe this would be a first for the GFS being the most tucked in near the coast with a snowstorm among the other globals and being correct. The NAM has done it numerous times. But the only other big GFS coup was being more east in January 2015.

It’s great to see the Euro AI correct the East Coast storm suppression issues that the regular Euro has since the upgrade around 2015.

I believe the 2-1-21 KU event and the follow up system about a week later. But the Canadian did have the wild further west run about week before which was close to what verified. Even though the Euro was too suppressed for both systems.

That was our last top tier KU event in December.

We all did great with that one but the jackpot was west of the Hudson in NJ.

Yeah, most events jackpot either east of NYC or to the west. January 2016 and 2006 were the rare events that maxed out right across NYC and the boroughs. The heaviest snow for any given event usually ends up in the interior or across Long Island.

It’s the always last 12 to 48 hrs of the forecast which really counts. We won’t be there until tomorrow into the Sunday 0z runs. But it’s certainly possible that we get a meet in the middle scenario between the most westerly GFS and the other guidance.

The GFS is the only model going negative tilt so fast so the low tucks in more near the coast. All the other guidance has the low consolidating a little further east and a slower negative tilt. The GFS is usually incorrect when its coastal low is the furthest west of all the other guidance. Sometimes the Euro does the same thing. I would probably shade toward the other guidance at this point and just broad brush the forecast to indicate that the chances for a 6”+ event near the coast are increasing and issue winter storm watches and wait until tomorrow to refine the warnings and higher end potential areas.

My only issue with the OP GFS is that the low further east usually becomes the main low like the Canadian and other guidance is showing.

The 12z Canadian also had a nice run showing 6”+ potential closer to the coast.

This is a great example of why we use the ensemble means at this range. The EPS AIFS has been very steady for days now with only gradual shifts from run to run. It hasn’t shown any big jumps from run to run like OPs. The OP runs should begin to converge over the next 24 hrs.

This is one of those rare times that the Northeast was colder than other areas instead of warmer. Climatologist49 ‪@climatologist49.bsky.social‬ Follow Winter-to-date temperature departure from normal. Currently on track to be the 2nd warmest winter on record (1895-present).

Even though we rebounded back into the 40s since early February, the warmest departures have been missing miss the Northeast relative to other regions. So the Northeast continues to hold into the colder pocket compared to the rest of the CONUS. The forecast into early March looks like more of the same.

You picked a great week to go down there since you missed the rare Arctic outbreak earlier in the month. https://www.youtube.com/watch?v=IxdEmS9gM1M

Good to see the EPS AIFS showing the growing storm potential. Not a bad signal from a day 5-6 AI ensemble. Let’s see this hold for another few days so we can pick up our first warning level event in a month.

Thread the needle is slang for getting a perfectly timed phase or storm separation between multiple systems. So I think this forecast qualifies. Would probably just use an ensemble blend at this point since OP runs day 5-6 usually change over time. Hence the you never want to be in the jackpot expression days 5-10. That being said, the storm signal is growing. But we’ll need a perfectly timed storm separation and phasing to get some of the higher end OP solutions. This can be a challenge so I will just go with the more conservative ensemble means until the specific details come into better focus. The highest scoring guidance this winter so far has been the EPS AIFS. But like all the other guidance it’s better under 72-120 hrs. So we still want to see the storm signal hold the closer in we get.

This would be our biggest rabbit out of hat event in years if we get the storm spacing and phasing to work out just right. The general storm signal continues to grow. But it’s tough to lock in details around day 5-6 when so much can change between now and then.

We have had smaller events like the 6z Euro presently shows for the 2nd system. But it’s rare to get a 12”+ like a few of the OP runs have been showing only 2 days after another system. That’s why I am going with an ensemble mean blend right now for the 2nd system. But since nothing is impossible, I am watching to see if the ensemble means move toward some of the more amped solutions in coming runs. Really volatile and delicate set up.

The OPs have been shifting around on the track and timing every 12 hrs. So we should just use an ensemble blend at this point and hold off on the details for a few days. It’s tough to get one really big storm when the systems are only 48hrs apart. But it’s not impossible. We will need some extra thread for this needle.