Weekly Outlook, Winter Weather

Weekly Outlook: December 30, 2019 – January 5, 2020

Another year has come and gone, but before we get to New Year’s Eve, we’ve got quite a mess to deal with today.

A variety of Advisories and Warnings are in effect across the Northeast today. Image provided by Pivotal Weather.

Low pressure will move into the Great Lakes today, with a frontal system extending eastward to the Mid-Atlantic coastline. This will keep us on the cold side, but warmer air will move in aloft. When you have warm air aloft, cold air below, and precipitation, you get sleet or freezing rain, depending on how thick the layers of warm and cold air are. For today, we’re looking at freezing rain across the higher elevations of Worcester County up into the Monadnocks, with a mix of sleet and some freezing rain from southern New Hampshire into the Merrimack Valley and interior portions of eastern Massachusetts. This will result in significant travel problems, not to mention the potential for tree and power line damage. For the rest of our area (mainly south and east of I-95), warmer air moving in off the ocean will keep temperatures above freezing, so it’ll be just another rainy, but chilly, Monday.

The potential still exists for some significant sleet accumulations from the Merrimack Valley into Southern New Hampshire today. Image provided by WeatherBell,

A secondary area of low pressure will move off the Mid-Atlantic coastline tonight, and pass across Cape Cod before moving into the Gulf of Maine on Tuesday. This should force the warmer air farther inland, with a change to plain rain for most of the area, though sleet and/or freezing rain will still be likely up into central New Hampshire. As that low moves into the Gulf of Maine on Tuesday, everything will start to wind down in the morning.

Freezing rain will likely cause problems from the Worcester Hills into the Monadnocks and also across the Berkshires today. Image provided by WeatherBell.

As for New Year’s Eve, the original low pressure area from the Great Lakes will pass north of the region, dragging a cold front through. Although it will likely remain dry, a few snow showers or flurries can’t be ruled out during the evening. Skies should be partly to mostly cloudy at night, with midnight temperatures generally in the 30s. An upper-level low will move across the region on New Year’s Day, so we’ll have some clouds, but probably not any flurries, though it will be seasonably chilly. High pressure then builds in for Thursday with sunshine and seasonable temperatures.

The next storm system moves into the Great Lakes Friday into Saturday. Oh great, another ice storm, right? Nope. This time, it looks milder (much milder on some models), so we’re looking at mainly rain, probably not a lot of it though. An early look at the weather for Foxborough Saturday evening (don’t get us started on the fact there will actually be a game this weekend), is for partly cloudy skies, light winds, and temperatures in the lower 40s. Drier and colder air settles in for Sunday.

Highs in the 50s on Saturday? The GFS thinks so, We’re not convinced yet. Image provided by Weathermodels.com

Monday: Breezy with sleet and freezing rain across the interior, rain along the coast. Sleet accumulations of an inch or two are possible across the Merrimack Valley and southern Hampshire, while up to 1/2″ of ice accretion is possible across the higher elevations of the Worcester Hills and the Monadnocks. High 30-37.

Monday night: Precipitation changing to all rain most areas, except sleet and freezing rain continue across central New Hampshire. Temperatures will slowly rise overnight.

Tuesday: Rain tapers off and ends in the morning, some sunny breaks may develop in the afternoon. High 39-46.

New Year’s Eve: Partly cloudy, chance for a snow shower or flurry during the evening. Low 25-32.

New Year’s Day: A mix of sun and clouds, breezy. High 34-41.

Thursday: Sunshine and just a few clouds. High 36-43.

Friday: Cloudy with some light rain or showers likely. High 40-47.

Saturday: A cloudy start, then becoming partly sunny. High 48-55.

Sunday: Intervals of clouds and sunshine. High 36-43.

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Heavy Rain/Snow, Winter Weather

Another Messy Monday

As we head into the home stretch of 2019, it looks like the year is going to end with a wintry mess.

Winter Storm Watches are in effect across interior portions of New England and eastern New York. Image provided by Pivotal Weather.

The storm system that produced heavy snow in the Plains and strong to severe thunderstorms in the Mississippi Valley on Saturday will head into the Great Lakes on Sunday, then just mill around in the Midwest for Monday and early Tuesday. Clouds will stream into our area later Sunday ahead of the system, but as is usually the case with a storm that far west, the warmer air that we usually find on the east side of a storm system won’t make it in here, at least at the surface (that becomes important later on).

Sunday will be a mild day (by late December standards) as high pressure moves out, but temperatures should drop below freezing during the evening. We’ll see precipitation start to break out before midnight across much of the area. While there will still be cold air in place at the surface, warmer air will be starting to move in aloft. So, we should see sleet and some freezing rain developing, with some snowflakes, mainly from central and southern New Hampshire northward. Some accumulations are possible, especially from the Seacoast up into the Lakes Region, but only a few inches at most before a change to sleet occurs. Along the South Coast, this will be mainly rain with temperatures above freezing.

The NAM model shows the progression of the storm system and how the precipitation changes from sleet to freezing rain, to rain across the region. Loop provided by Tropical Tidbits,

With a frontal system stalled out south of New England, we’ll have generally east to northeast winds on Monday. This will allow parts of southeastern Massachusetts and Rhode Island (mainly south and east of Interstate 95), to warm above freezing as somewhat milder air moves in off the ocean. Across inland areas, it’ll be a much different story.

This graphic shows the difference in how you get snow vs sleet vs freezing rain. Image provided by NOAA.

Cold air will remain in place for most of the day on Monday and into Monday night. Meanwhile, a few thousand feet above the ground, warmer air will be moving in. This will mean sleet at first, but as that warmer air layer grows thicker, the sleet should transition over to freezing rain. When that transition occurs is still a bit of a question mark.

NAM model forecast for temperatures at 700mb (about 10000 feet) for midday Monday. Temperatures will be above freezing across most of our region that high up, melting any high-level snowflakes falling into that part of the atmosphere. Image provided by the College of DuPage.

Some models are showing the potential for significant amounts of sleet from interior eastern Massachusetts into southern New Hampshire, with significant ice accretion from freezing rain across the Worcester Hills, Monadnocks, and the Berkshires. No matter what happens, travel will be very slippery across the interior on Monday,

The High-Resolution NAM model is forecasting a LOT of skeet across the interior. Image provided by WeatherBell.

By Monday night, a secondary area of low pressure should develop south of Long Island, and it will head northeast, moving across Cape Cod early Tuesday, then into the Gulf of Maine. As it moves close to the area, it should help force the warm air farther inland, allowing temperatures to rise above freezing across most of the area. However, once it moves into the Gulf of Maine, colder air will settle in behind it, both at the surface and aloft, changing everything back to snow showers before the precipitation winds down Tuesday morning.

Significant ice accretion could result in major issues including tree and power line damage across the interior. Image provided by WeatherBell.

We’ll update this forecast as well as a look at New Year’s Eve and New Year’s Day in our Weekly Outlook early Monday morning.

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Weekly Outlook

Weekly Outlook: December 23-29, 2019

As we get to Christmas Week, we’ve got a very quiet pattern shaping up for the region. That doesn’t mean the forecast is simple though.

We start the week off on a mild note with high pressure still in a control, but a weak cold front will move through late in the day with little fanfare. It’s most noticeable impacts will be behind it, as temperatures drop back close to seasonal levels for Christmas Eve and Christmas Day, with highs in the 30s instead of the 40s to lower 50s most places will enjoy today.

Much of the area could see temperatures top 50 this afternoon. Image provided by WeatherBell.

Thursday looks to be a tad milder, but we’ll have a weak disturbance moving across the region. It may produce a few rain or snow showers late Thursday night into part of Friday, but this will not be a widespread precipitation-maker. High pressure builds back in for Friday night into Saturday before we turn out attention to the next storm. This one also has some big questions, but for now, it looks like we could have some rain around here next Sunday:

Monday: Sunshine gives way to some late-day clouds. High 46-53.

Monday night: Cloudy in the evening, then clearing after midnight. Low 25-32.

Christmas Eve: Partly to mostly sunny and cooler. High 35-42.

Christmas Eve night: Becoming partly to mostly cloudy. Low 18-25.

Christmas Day: Sunshine filtered through some high clouds. High 34-41.

Thursday: More clouds than sun. High 34-41.

Friday: Plenty of clouds with a few sunny breaks, chance for a few snow or rain showers early. High 34-41.

Saturday: Intervals of clouds and sunshine. High 39-46.

Sunday: Cloudy with a chance of rain. High 39-46.

Whatever you celebrate, we wish you a happy one!
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Extreme Temperatures, Heavy Rain/Snow, Winter Weather

Messy Tuesday, Frigid Thursday

The Winter Solstice is Saturday, but winter will certainly make it’s presence felt over the next few days.

The low pressure system that produced severe weather across the South on Monday will head northeastward, impacting our area on Tuesday. The storm will be moving fairly quickly, and it doesn’t have a lot of cold air to work with, so we’re not expecting a big snowstorm. That doesn’t mean it won’t cause any problems.

Winter Weather Advisories are in effect for most of the region. Image provided by Pivotal Weather.

Snow will develop around midnight across parts of Connecticut and Southern Rhode Island, gradually spreading northward across the rest of the region before daybreak. The snow should quickly change to rain after daybreak across the South Coast and Cape Cod. As warmer air moves in aloft, a change to sleet and freezing rain will start to take place across the interior, with plain rain along the coast as milder air moves in off the still relatively mild ocean. Right now, it looks like the mixing may get as far north as the Merrimack Valley during the afternoon. North of there, precipitation should stay all snow. The precipitation will lighten up during the afternoon, but won’t completely end until the evening or first part of the overnight.

The morning and evening commute will both be impacted by this storm, but the greater impacts will certainly be during the morning commute. Not only could icing be a problem, especially in parts of Connecticut and Rhode Island, we could be looking at a band of moderate to heavy snow along and south of the Mass Pike. With temperatures expected to drop below freezing at night, many roads could ice back up, so untreated surfaces could become slick, especially in areas that changed over to rain during the afternoon.

Icing could become a significant problem across parts of Connecticut and Rhode Island on Tuesday. Image provided by Pivotal Weather.

As for how much snow to expect, we haven’t changed our thinking much from our earlier forecast.

South Coast/Cape Cod: Less than 1″
Southeastern Massachusetts (including the I-95 corridor): 1-2″
MetroWest/North Shore: 1-3″
Merrimack Valley: 2-4″
Central + Southern New Hampshire/NH Seacoast: 3-6″

The High Resolution NAM model is probably closest to our expectations for snowfall. Image provided by WeatherBell.

Behind this system, we’ve got to pay attention to an arctic cold front that will move across the region late Wednesday. It could produce some snow showers or squalls as it moves through. These won’t impact everyone, but in places they do, visibility could rapidly drop, and a quick half an inch to an inch of snow could fall.

Wind chills will likely drop below zero across most of the area Wednesday night into Thursday morning. Image provided by Weathermodels,com

Behind that front, some of the coldest air so far this season will settle in for Thursday. Wind chills will be below zero during the morning hours, and actual temperatures may not make it out of the teens during the afternoon. Friday will see temperatures start to moderate a bit, but it will still remain quite chilly, even by December standards.

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Heavy Rain/Snow, Weekly Outlook

Weekly Outlook: December 16-22, 2019

We’ve got another week coming up with just about everything Mother Nature has to offer. Well, not quite everything, since we won’t have a warm day this week. To make up for it, we’ll have at least one day that is extremely cold. How’s that for a trade off?

The week starts off with high pressure in control. That means we’ll have some sunshine, less wind, and chilly temperatures today. The sunshine will not last long though, as clouds quickly move in ahead of our next system. That storm will move from the Tennessee Valley into the Mid-Atlantic states, passing south of New England on Tuesday. That’s about the only part of the storm that isn’t complicated.

Snow will develop across much of the region before daybreak on Tuesday. Yes, that means your morning commute on Tuesday will be even worse than normal. The snow should quickly change to rain along the South Coast. Away from the coast is where the problems start. Warmer air will move in aloft, with a change to sleet, freezing rain, and eventually plain rain expected to work its way northward on Tuesday. How quickly it moves northward, and how far north that changeover gets are still up in the air. Obviously, this has a major impact on how much snow accumulation we can expect. The other problem is, how long do some areas stay sleet or freezing rain, as this will have a significant impact on road conditions.

The High-Resolution NAM model shows the progression of the the precipitation and changeover line with the next storm system. Loop provided by WeatherBell.

So, how much snow can we expect before the changeover? Obviously, this is still a low-confidence forecast, despite the fact that it’s only a little more than a day away. Here’s what we’re thinking for now:

South Coast/Cape Cod: Little to no accumulation
Southeastern Massachusetts/Rhode Island (South and East of I-95): A coating to 2 inches.
Northern Rhode Island/MetroWest/North Shore/Merrimack Valley/NH Seacoast: 1-3″
Southern NH (Nashua-Manchester): 2-4″
Central NH (Concord-Lebanon): 4-7″

We’ll try to do an updated blog post late Monday, once we get a little more clarity on some of the details.

The GFS model is probably the closest to our thinking for snowfall amounts right now. Image provided by Weathermodels.com

So, everything winds down Tuesday evening, and then things improve on Wednesday, right? Not so much. A strong cold front will move across the region during the afternoon. This front may produce some snow showers or possibly snow squalls as it moves through during the afternoon and evening. Behind the front, some much colder air settles in for Wednesday night and Thursday. Now, it won’t be as cold as it was in the Dakotas and Minnesota, where it stayed below zero all day Saturday and Sunday (Can someone please explain why people choose to live in North Dakota?), but many parts of our area could stay below 20 all day on Thursday. When you fact in the wind, it will feel like it’s below zero, especially during the morning.

Heading out before daybreak Thursday? Bundle up, because wind chills will likely be below zero across the region, Image provided by WeatherBell.

High pressure builds in for Friday with dry weather, but it shouldn’t be as cold as Thursday. This brings us to the weekend. This is where things get questionable again. You may have heard some chatter online about a big snowstorm this weekend. Well, it’s a possibility, but then again, it’s also possible that the Patriots defense won’t give up a single point for the rest of the season. Most of the models have been signalling that there will be a potent storm system developing off the East Coast this weekend. Every now and then, one of the runs puts that storm right off of Cape Cod and shows the potential for a blizzard, sending all of the Facebook Forecasters into a frenzy. Of course, these same models have also shown the same storm moving off of Florida and then eastward across the Bahamas instead. Will there be a strong storm? Probably. Will it impact us? Probably not. However, one thing that may happen, is a weak system moving eastward bringing in a period of light snow sometime either late Saturday or Sunday. Given where the storm forms, it’s not really an Alberta Clipper, calling it a Dakota Dasher would probably be more accurate.

Nearly every run of the GFS over the past 5 days has had a strong storm near the East Coast this weekend. However, the placement and strength of the storm has varied on every run. Loop provided by Pivotal Weather.

If you’re really looking ahead, right now Christmas Eve and Christmas Day look dry and seasonably chilly.

Monday: Some sunshine early, then clouds thicken up. High 30-37.

Monday night: Cloudy with snow developing after midnight. Low 23-30.

Tuesday: Snow, changing to sleet, freezing rain, and plain rain from south to north. Areas north of the Mass Pike may never go to plain rain. High 27-34 north and west of Interstate 95, 34-41 south and east of Interstate 95.

Tuesday night: Precipitation ends in the evening, then skies clear out late at night. Low 21-28.

Wednesday: Morning sunshine, clouds return in the afternoon with some snow showers or squalls possible late in the day, becoming windy at night. High 30-37.

Thursday: Sunshine and a few clouds, breezy, and cold. High 17-24.

Friday: Partly to mostly sunny. High 22-29.

Saturday: Mostly cloudy, chance for some light snow or snow showers late in the day and at night. High 29-36.

Sunday: Partly to mostly cloudy with a chance of snow showers, especially in the morning. High 34-41.

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Extreme Temperatures, Heavy Rain/Snow, Weekly Outlook, Winter Weather

Weekly Outlook: December 9-15, 2019

Given a choice, would you prefer cold weather or warm weather? What about a choice between rain, snow, or dry weather? Well, you’re going to get ALL of these this week!

Temperatures could reach 60 across parts of the area on Tuesday. Image provided by WeatherBell.

We start the week with low pressure moving into the Great Lakes and then eventually up the St. Lawrence Valley. With low pressure passing to our north and west, we’ll be on the warm side, with rain expected, mainly in two waves. The first one will come in today, with rain developing this morning, and continuing into tonight, when it cold be locally heavy. The warm air should move in south of Boston fairly quickly, but it may take until tonight to get into the Merrimack Valley and southern New Hampshire.

Warm air comes in today, and is quickly pushed out by cold air late Tuesday into Wednesday. Loop provided by Weathermodels.com

We’ll have a bit of a lull tomorrow morning, but a cold front will approach later in the day, with rain coming back ahead of that front. We’ll still be on the mild side, that is until the front comes through. Temperatures will quickly drop behind the front late Tuesday and Tuesday night but the precipitation may linger, so we will likely see rain changing to snow Tuesday night.

The NAM model shows the progression of the storm with 2 waves of rain followed by some snow. Loop provided by Tropical Tidbits.

On Wednesday, a little disturbance will move across the region, bringing us some additional light snow, mainly in the morning. There’s still a bit of uncertainty with this, but plan on the morning commute being impacted. We’re probably only looking at a few inches, but all it really takes to screw up the morning commute is a few flakes at all. High pressure builds in late in the day and into Thursday with drier and much colder weather.

A few inches of snow could really mess up the Wednesday morning rush hour. Image provided by Pivotal Weather.

By Friday, temperatures start to moderate again as the high slides offshore. It’ll still be chilly (it is December after all), but not quite as cold as Thursday. The weekend looks even milder once again, but that’s because we’ll have another storm system passing to our north and west, so we’re looking at another round of rain, possibly heavy once again.

Saturday could end up quite mild once again, but wet as well. Image provided by WeatherBell.

Monday: Cloudy and becoming breezy with periods of rain and showers. High 49-56.

Monday night: Cloudy and breezy with rain likely, possibly heavy at times, tapering off late at night. Temperatures hold steady or possibly rise a few degrees.

Tuesday: Cloudy and breezy with showers redeveloping late in the day. High 53-60, but temperatures start to quickly drop from northwest to southeast during the afternoon.

Tuesday night: Cloudy with rain changing to snow during the evening. Low 26-33.

Wednesday: Cloudy with light snow ending around midday. Skies clear out at night. Temperatures hold steady or drop a few degrees during the day.

Thursday: Plenty of sunshine, but cold. High 24-31.

Friday: Becoming mostly cloudy. High 32-39.

Saturday: Cloudy, breezy, and milder with rain likely. High 46-53.

Sunday: Partly to mostly cloudy and breezy, chance for a few showers. High 42-49.

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Heavy Rain/Snow, Weekly Outlook

Weekly Outlook: December 2-8, 2019

Winter’s back, and it’s not going anywhere for a while. We’ve got more snow on the way in the next 24 hours, so we’ll get right to it.

Some moderate to heavy snowfall totals were observed on Sunday, especially north and west of Boston. More will be coming today into Tuesday. Image provided by the National Weather Service in Norton, MA.

We went into great detail yesterday, so we won’t spend too much time on today. Basically, the daylight will be fairly quiet as the low move towards the Gulf of Maine. We’ll have some occasional showers and/or drizzle across eastern Massachusetts, with freezing drizzle or a few flurries farther inland and up into southern New Hampshire. Late in the day, temperatures will start to drop, so things could get icy across eastern Massachusetts as well.

The High-Resolution NAM model depicts the progress of our storm system today into Tuesday. Loop provided by Tropical Tidbits.

Tonight is when things get interesting again. As the low pressure area moves into the Gulf of Maine it will intensify and become a pretty potent system. With gusty north to northwest winds keeping most of the area quite chilly, we’ll snow moving in from the ocean, on the backside of the storm. It is still uncertain how far inland that snow will get and how much will fall. We’re fairly confident that there’s going to be a band of heavy snow that sets up, but we’re still thinking that the heaviest stays just offshore. Still, with light to occasionally moderate snow going through Tuesday afternoon, we’ll still see some decent amounts, especially close to the coast. How much more? We think that much of the region could see 3-6″ between Monday night and Tuesday afternoon, with lesser amounts into southern New Hampshire. From the North Shore up into the New Hampshire Seacoast , another 4-7″ may fall.

The High Resolution NAM model is closest to our thinking for snowfall tonight into Tuesday. Image provided by WeatherBell.

Everything winds down Tuesday night, then high pressure builds in for Wednesday and Thursday with dry and chilly conditions. An Arctic front will move across the region late Friday, with a few snow showers or squalls ahead of it. After that, high pressure returns next weekend with even colder weather on Saturday. By Sunday, the high will slide offshore and temperatures will start to moderate, but will likely still be below normal for early December.

Temperatures may stay below freezing all day on Saturday. Image provided by WeatherBell.

Monday: Cloudy and breezy with showers and drizzle across eastern Massachusetts, flurries and freezing drizzle elsewhere. High 29-36 north and west of I-95, 37-44 south and east of I-95, though temperatures in this area will start to drop in the afternoon.

Monday night: Cloudy and breezy with precipitation becoming steady light to occasionally moderate snow. Low 24-31.

Tuesday: Cloudy and breezy at times with snow ending by early afternoon, some sunshine may develop in the afternoon the farther west you go. Additional accumulation 1-3″ in southern NH, 3-6″ most elsewhere, except 4-7″ from the North Shore to the NH Seacoast. High 30-37.

Tuesday night: Partly to mostly cloudy. Low 18-25.

Wednesday: More clouds than sunshine. High 34-41.

Thursday: A mix of sun and clouds. High 32-39.

Friday: Partly to mostly cloudy with some late-day snow showers or squalls possible. High 34-41.

Saturday: Sunshine and a few clouds, breezy. High 26-33.

Sunday: A mix of sun and clouds. High 36-43.

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