Thursday evening into Friday we will see a developing low pressure system begin to “bomb” off the New England Coast, bringing with it rain, snow, wind, and almost everything in between.
Moisture from the gulf of Mexico (seen above at 48 hours, 00z Thursday) will begin to ride a quickly deepening trough late-week. As the storm rides up the coast late Thursday, all eyes are focused on the position and strength of the rapidly intensifying low. As of the latest runs, the NAM is trending slightly east of the ECMWF as of 06z Friday. The GFS seems to be more progressive than the other two, and also seems to be underestimating the QPF we often to see with these moisture-rich systems.
Here, we see the bombing low’s placement, riding a negatively-tilted trough as of 06z Friday, according the Euro. It is always fascinating to see how quickly these storms explode off the coast: between 18z Thursday and 06z Friday, the low deepens from 1004 hPa to 976 hPa(!) according to the most recent NAM run. Even though this will not be a long-duration Nor’Easter, we will still see ample moisture, with QPF totals around 1-2″ for most of Central and Eastern MA (higher totals further east). However, the GFS, being more progressive with the storm, does not have nearly as much precip. falling over Southern New England because the storm is not fully developed at the time of impact. It is the outlier in that sense.
Now, the question on everyone’s minds: will it be rain or snow? Well… latest model trends have shown a more inside track, rather than the classic “Benchmark Blockbuster”. In fact, the GFS and the ECMWF both show temperatures around and within the I-495 corridor above freezing up to 925-hPa! This seems to be a snowstorm for interior Central New England, and Northeastern New England, the way the models are currently trending. Here’s a peek at the Euro’s snowfall projection through 1 PM ET Friday. Keep in mind… The Euro is the “snowiest” solution, as of now.
Along the coastal plain, surface winds will likely gust 30-40 mph, with up to 50 mph possible on the Cape and Islands, as well as possibly the North Shore, as intense cyclogenesis occurs.
It can’t be stressed enough: minor changes in the rain/snow line will have SIGNIFICANT impacts on our area. As is stands now, there is potential for 3-6″+ (possibly much more) outside of I-495, 2-4″ inside I-495, and even less south and east. Key word: Potential. If the storm slows down and trends further East, totals up to (and over) 12″ would not be out of the question for portions of Central and Northern MA, as well as some locations in inland NH and (particularly) interior Southern and Central Maine.
Stay Tuned to UML Weather Center for future updates because these fine details WILL change!