The potential exists for a major East Coast storm this weekend, but it’s just as likely the storm passes to our south, harmlessly out to sea. Even if we get a storm, it’s not clear if precipitation would take the form of snow, rain, or some sloppy combination. In other words, right now we have more questions than answer.
If a storm materializes, it would most likely affect the area Saturday night into Sunday. However, such a scenario requires a complex set of ingredients to come together. The balance of available long range weather forecast models (the Euro, Japanese, Canadian, and Navy NOGAPS) indicate they will not. Instead, they favor a scenario that takes an area of low pressure from the Gulf of Mexico to our southeast, maybe just grazing our region.
But other models (namely the GFS and the UKMET) bring all of the pieces together and blow up a formidable storm along or just off the mid-Atlantic coast. The problem for snow lovers in this scenario is that the storm develops so much is that it pulls in warm air off the ocean, resulting in mostly rain in the immediate D.C. area. This scenario might bring substantial snow along and west of the I-81 corridor.
For snow lovers in the immediate Washington/Baltimore area near I-95, a few of the GFS models’ ensemble members (versions of that model with slightly tweaked initial conditions) simulate snowier outcomes. And the mean (or average) of all of these members is snowier. But the ensemble mean is not an actual storm simulation. It does suggests many of the GFS’ ensemble members favor a weaker storm with a track farther offshore than the main operational model. That’s not a bad thing if you’re rooting for snow.
Snow lovers probably should pull for a storm that is not too strong but not too weak and close to to the coast but not too close. But that’s asking a lot of the atmosphere during a year in which the deck has been stacked against a snowy setup.
Right now, we don’t think odds are high for substantial accumulating snow in the immediate metro region. Too many pieces would need to come together. Importantly, the amount of available cold air for any storm to tap is marginal for significant snow, at best.
CWG’s Wes Junker described the state of the forecast as such:
The models are changing positions more than some politicians change their stances depending on their audience. The European model, which yesterday morning was showing a potential snowstorm (but with marginal surface temperature issues for snow), for the third straight run has the low tracking far enough south and east to keep us out of any precipitation. The GFS which had the flat solution jumped to a major east coast storm at 7 p.m. and again this morning. The UKMET model is flipping back and forth.
The wild gyrations of the models from run to run suggests there is little certainty about the storm. Therefore, any definitive call concerning the storm will have to wait until there is better continuity and consensus among the models. The best forecast for the storm at this juncture is to call for a chance of rain or snow. However, there also is an equal chance of the low missing us to the south.