The good news for snow lovers is that chances are increasing for a major East Coast winter storm early next week. Considering it is mid-March this will likely be our last chance of the season for some worthwhile snow. Remember, we’ve only accumulated a paltry 1.4” of snow in DC so far this winter. The bad news is, as with most winter storm systems, there are still plenty of unknowns two and a half days out. These weather models can change, especially in regards to where the ever-tricky rain/snow line sets up over our area.
That being said, the latest model guidance suggests that a phasing low pressure system to our south will spread snow into the region after sunset on Monday. So, both the AM and PM commutes look fine for the first day of the work week. Snow showers of varying intensity are expected overnight Monday into early Tuesday morning. The fact that snow is moving in overnight helps increase our likelihood of accumulations. During the day Tuesday warmer air will nudge westward into the intensifying storm system; likely bringing in a rain/snow mix south and east of DC. How far west that spreads during the day Tuesday is still up for grabs. However, any mixing will greatly limit accumulations.
The storm system is expected to pull away Tuesday night with snow showers gradually tapering off overnight. We should wake up to dry (but very cold!) conditions Wednesday morning.
Here is a look at projected snowfall accumulations from our two major weather models. First we have the American GFS model. It favors a colder, deeper low pressure system which would bring us higher snowfall amounts. The most snow would accumulate north and west of DC, where the cold air sticks around longest.
Yes, those are some jackpot numbers of 12-18” in our vicinity!! Notice the very sharp gradient right along I-95 and the DC metro. That’s your rain/snow line at work. Now, let’s look at the latest European model snowfall output:
Wow, what a difference. This model says that enough warm air and mixing will work its way into the system to greatly limit snowfall accumulations here. Higher amounts are favored up near Philadelphia and North Jersey. This is why it’s a little too early to nail down specific snow totals.
Bottom line, there will be a big winter storm in the Northeast Monday-Wednesday. The timing for us is overnight Monday through the day Tuesday. A period of accumulating snow is likely. And very cold temperatures continue through the whole week. Stay tuned through the weekend for updated information.