I just released a comprehensive premium post on the lessening potential for a storm this weekend, but I also wanted to release some of it here as well so that I can continue to integrate in continued free content and keep everyone updated on the potential this weekend. Models backed off fairly significantly on the strength of the storm, and in the Premium post (available here) I have a detailed explanation of what exactly could change that could result in a stronger storm, as there is a lack of interaction, or phasing of energy, in the upper atmosphere. I’ll attach the part of the forecast discussion where I explain why this may not be our final solution and I’ll show you what some of the computer guidance also shows at this time as well:
First, our weather models, on a whole, are pretty bad. One would hope that in the 21st century our models would be able to properly predict a storm like this 5 days out, or at least remain consistent in their output instead of changing so drastically from run to run. However, there are a number of reasons why the models do this, and one of the key reasons is of no fault of weather models themselves. The data is bad. There is a known whole in data offshore in the Pacific Ocean, namely in the Northwest Pacific “dead zone.” There are no weather balloons launched there, meaning that when models try and forecast what energy in that region will do, they could be starting all wrong. It’s doomed from the start. The energy from the storm we are currently following is currently just offshore of the US west coast and will be moving onshore by tomorrow morning. What that means is by 12z tomorrow, and especially 0z tomorrow, the energy for the storm will be properly sampled and will be better integrated into the models. Could it be that the weaker trend with the models is warranted? Certainly. I will detail a scenario where it could be wrong, but also show what happens if it is right. This just means that there is a distinct possibility that these model trends today (and it really was just a trend with the two runs today of our major models) may be just one-day events and not sustained against a storm happening. Anyways, that is why I caution letting your guard down for storm possibilities, even when the models are fairly unimpressive, which they are with this storm.
However, even being fairly unimpressive, the storm would still bring light to moderate snow across inland areas and a rain/snow mix to the coast, generally in line with what I expected. The latest GFS weather model, the 18z run, shows this for Sunday morning. It has a very weak low pressure center far to the southeast, but still has some light snow showers (seen on the bottom right) over the region associated with the weak upper level trough (seen on the top left) swinging across the Northeast. The consensus among our weather models is that, in a worse-case scenario, there will be at least some precipitation (likely snow even to the coast) with such a weak trough. The CMC, shown here, also shows accumulating snow across the region Sunday afternoon. The ECMWF, shown here, also has a signal for an inverted trough setting up on Sunday that could produce light snow. And the DGEX model (not very accurate as an extension of the NAM, but worth showing), shown here for Sunday morning, shows moderate snow inland with rain/snow at the coast. So models do agree on at least some snow moving through the region coming from the upper level disturbance and maybe an associated low pressure center at the surface. Models have just trended against a stronger surface low pressure center, and that is why I am not quite as concerned.
So that’s what I am following right now! If you’re someone looking for daily updates not on just this storm threat but also the next one (around December 24th) or interested in the long-term weather patterns and their implications in the natural gas market, then the premium post contains all of that. However, I’ll continue to post briefer updates like this on the storm until it comes time for the release of the official forecast a couple days before the storm hits. The overall consensus is that at least light snow inland and a light rain/snow mix at the coast is likely Sunday, primarily in the afternoon and evening, with the potential for something stronger. Stay tuned for the latest as we track this potential weekend storm!