Storm could deliver rain, snow

It’s still very early and the forecast can certainly change, but the timing looks like late Thanksgiving night through most of Friday could be messy.

The latest models indicate that this storm may arrive later than originally thought and become more of a Black Friday storm than a Thanksgiving storm. Another possible track shows with good confidence that the jet stream will be bent and try to parallel the coast, which could send the core of this low offshore as it approaches New England to create a more impactful storm.

In other words, this has the potential for a nor’easter.

A strong low pressure system, a nor’easter, is simply a storm setup with winds coming in from the northeast – it doesn’t necessarily mean we’ll get lots of heavy snow or rain. Right now it looks like mostly rain in Boston and the rest of southern New England and snow up north. Remember, it’s still very early and this forecast is definitely subject to change.

The amount of precipitation will depend on how much moisture is available over the North Atlantic versus how cold the air is over land. This contrast creates instability – or rather energy – in the atmosphere, where the relatively moist air rises quickly and condenses into rain or snow.

Regardless, it will be worth seeing how things stack up over the next few days.

Right now, most models have the core of this low footer right off the southern New England coast Thanksgiving night, which will make it interesting. This storm looks unlikely to be a full-scale blizzard, but guidance agrees that there will be some messy weather that wreaks havoc on travel plans, with rain, snow and gusty winds involved.

Southern New England weather forecast

This system should be mainly a rain event across Rhode Island, eastern Massachusetts and Connecticut through at least Thanksgiving night and most of Friday. It’s really too early to get into rain and snow, but there should be enough cold air present, especially on the backside of the system, to bring some sleet, ice or snow into the picture at times across the mountain towns of Central and Western Mass. We will see what track this storm takes, which of course will dictate where the rain-snow line settles.

If I were to commit to rain and snow totals, given all the variables at play here, I would expect between 1 and 1½ inches of rain across southern New England, with possibly 2 to 4 inches across the western four counties of Massachusetts.

Windy conditions are likely with gusts up to 25 to 30 miles per hour, especially along the coast.

Northern New England weather forecast

Right now, it looks like northern New England could get a shot of snow Thursday night and most of the day Friday, but trends for now show that snow may be concentrated in central and southern parts of Vermont, New Hampshire and Maine. Uncertainty in the exact storm track could bring rain or a wintry mix to the area overnight into Thursday, with a switch to all snow on Friday.

Again, if I were to throw out a snowfall I’d say between 3 and 6 inches, but this is really just a guess with how many variables there are to consider with a storm still four days away.

The weather will take a clearer shape as we get closer to the holidays, but make sure you take extra time on the roads and don’t rush to your destination.

Temperatures are sure to drop during the holidays. An arctic chill should be in place across the region on Thanksgiving with likely daily highs only reaching the low 40s and nighttime lows near or below freezing.

The cold air should continue into the weekend, with Black Friday likely to see temperatures barely reaching 40 degrees. Mornings will be much cooler as shoppers head out before sunrise to score some early holiday deals.

The upcoming storms, combined with recent rainfall from Thursday-Friday, are expected to help ease severe drought conditions after an unusually dry fall — on Nov. 17, Boston broke a 110-year record for its driest fall. Months of high pressure dominated the region, leading to extremely dry conditions throughout New England and an unprecedented number of wildfires in Massachusetts.

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Ken Mahan can be reached at [email protected]. Follow him on Instagram @kenmahantheweatherman.