Heavy Rain/Snow, Winter Weather

Out Like A Lamb? Not This Time

March is supposed to come in like a lion and go out like a lamb, or so the old saying goes. Well, it certainly came in like a lion, but now it’s also going to go out like a lion too. Don’t worry, a repeat of the April Fool’s Blizzard in 1997 is not coming, but we do have some snow to worry about across parts of the region.

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Looks like an active day for severe weather from the Ohio Valley to the Gulf Coast today. Image provided by the Storm Prediction Center.

The storm that we’ll have to contend with Friday into Saturday is moving into the Midwest today, with plenty of severe weather expected ahead of it. This system has already produced a lot of severe weather from the Southern Plains and Texas into the Mississippi Valley over the past couple of days. Don’t worry, we won’t have to contend with severe weather up here. As the storm heads into the Midwest, it will eventually redevelop off the Mid-Atlantic coastline and pass south of New England late Friday into Saturday. Meanwhile, high pressure will move into eastern Canada, keeping some marginally cold air in place, setting the stage for a return of wintry weather to New England.

We’ll have some snow or rain showers developing Friday morning, but with temperatures in the 30s to lower 40s, we won’t see much, if any, accumulation during the daytime. The sun angle is getting relatively high, so even with the cloud cover, it still is strong enough to prevent much accumulation, at least on paved surfaces.

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Forecast for the high-resolution NAM model for the Friday/Saturday storm system. Loop provided by Pivotal Weather.

After the sun sets, things get a lot more complicated. Without the sun, and with temperatures dropping into the lower to middle 30s, along with the heaviest precipitation moving in, we’re looking at a changeover to snow for most places, especially away from the coastline. The problem is, some warmer air looks like it will move in aloft for a while. With a warm layer aloft, the snow that’s falling melts, then starts to refreeze as it moves back into the colder air below that layer. The result is sleet, and possibly a lot of it well inland. This will significantly cut back on snowfall accumulations.

Once we get into Saturday morning, a change to rain is likely for much of the region, but even where it stays mostly snow, we won’t have much additional accumulation, at least on paved surfaces.  A few showers may linger into Sunday as an upper-level storm system moves across the region, then high pressure brings sunshine and seasonably cool temperatures in for Opening Day at Fenway on Monday.

So, how much snow are we looking at? We’ve bumped up amounts a little since yesterday, but nothing significant:

South of the Mass Pike: A coating at most.
Metro Boston: 1-2″
128 Belt: 2-4″
Merrimack Valley: 3-5″
NH Seacoast/North Shore: 3-6″
Southern NH: 4-7″
Worcester Hills/Monadnocks: 5-10″

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The high-resolution NAM model is probably closest to our thinking for snowfall amounts. Image provided by WeatherBell.

Before you ask, no, this is probably not the last time we’ll see snowflakes this season. It may be the last “snowstorm”, but even that’s not a definite. Remember, we’ve had snowstorms around here into late April and early May before.

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Winter Weather

No Joke – Snow Possible for April Fool’s Day

Easter Sunday, 1997. It’s a beautiful day with sunshine and temperatures getting into the 60s. So why are the meteorologists talking about Winter Storm Warnings? Well, as we all remember (at least those of us who lived around here at the time), we went from 60 degrees on Sunday to 2 feet of snow by Tuesday.  While there’s more snow in the forecast for March 31 and April 1 this year, we’re not expecting anything remotely close to what happened 20 years ago.

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Mother Nature certainly played one hell of a joke on all of us in 1997. Image provided by NOAA.

As we get into late March and early April, it becomes harder and harder to get a significant snowstorm around here. Oh sure, it’s happened plenty of times (just look at the map above), but we really need everything to be setup perfectly for it to happen. For Friday and Saturday, things are not setup perfectly, and that’s why we’re not expecting a big storm.

The storm system bringing severe weather to parts of the nation’s midsection yesterday and today will head towards the Great Lakes over the next day or two, then eventually redevelop off the Mid-Atlantic coastline on Friday. Meanwhile, high pressure building in north of us will bring sunshine and relatively cool weather in for Thursday. As that high moves into eastern Canada on Friday, it will allow winds to shift into the east and southeast across the area at lower levels of the atmosphere. As these winds blow in off the ocean, where water temperatures are in the upper 30s to lower 40s, it will allow air temperatures to rise to those same levels along the coastline.

Inland areas could be a different story. Winds may stay out of the north, allowing cold air to remain in place, keeping temperatures in the lower to middle 30s. As the precipitation moves in during the day, we’ll see it start as rain in many places, but well inland, and especially in some of the higher terrain, we’ll see snow, or at least a mix of rain and snow. Even though it may be snowing during the day, we’re not expecting much accumulation. The sun angle is getting relatively high, so even with the cloud cover, it still is strong enough to prevent much accumulation, at least on paved surfaces.

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NAM model forecast for the Friday/Saturday storm system. Loop provided by Pivotal Weather.

This brings us to Friday night, which is where things get very tricky. Without the sun, and with temperatures dropping a bit, along with the heaviest precipitation moving in, we’re looking at a changeover to snow for most places, and possibly some heavy snow, especially away from the coastline, right? Not exactly. Some warmer air looks like it will move in aloft for a while, about 7,000-10,000 feet above ground. With a warm layer aloft, the snow that’s falling melts, then starts to refreeze as it moves back into the colder air below that layer. The result is sleet, and possibly a lot of it.

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

Everything should change back to rain before ending on Saturday, but temperatures will likely only be in the 30s to lower 40s again. Not exactly a nice early Spring day across New England. A few rain or snow showers may linger into Sunday as an upper-level disturbance moves through, but sunshine should return on Monday, just in time for Opening Day at Fenway.

So, by now you’re wondering how much snow can we really expect? You’ve probably seen some of the model forecast snow maps posted on the internet or on TV already. Ignore them. All of them. They are useless in storms like this. Here’s what we’re thinking right now for accumulations:

Inside of 128: Little to no accumulation
Merrimack Valley/NH Seacoast/Northeast MA (away from the coast): 1-3″
Southern NH: 2-4″
Worcester Hills/Monadnocks: 3-6″

All in all, not a big storm, but the roads could be slick Friday night and Saturday morning, so if you have to head out during those times, please slow down and be careful. If anything changes, we’ll update this post on Thursday.

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Weekly Outlook

Weekly Outlook March 27-April 3, 2017

As we prepare to flip the calendar from March into April, it looks like a week of typical springtime weather in New England is in the forecast. What exactly is “typical springtime weather” in New England? Why, it’s a little bit of everything. Let’s get to the details.

The week starts off chilly and damp as a warm front tries to approach from the south. As rain moves in ahead of it, temperatures will be on the cool side, so we may even see a little freezing rain in the morning well north and west of Boston. If you live there or have to head there in the morning, take things a little on the slow side. The rest of Monday will be fairly wet, as a wave of low pressure rides along that front across the region. We’re not sure that front ever makes it completely across the region, so if you were expecting some milder conditions, you may be out of luck, especially the farther north you head. Another wave of low pressure rides along the front on Tuesday, giving us more rainfall. While a couple of cool and wet days doesn’t sound good, the rain is beneficial. We are still in a drought across the region, and need plenty more rainfall to break it.

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We still need a lot more rain to break the drought. Image provided by National Drought Monitor.

 

Once that wave of low pressure moves by Tuesday night, high pressure then builds in for Wednesday and Thursday. So, we’ll finally get some sunshine again, especially away from the coastline, but it will remain on the cool side, with temperatures staying a little below normal. (Highs should generally be in the lower to middle 50s as we head into early April.) This brings us to Friday and Saturday. Another system will approach from the west very slowly, and likely pass to our south. That means another extended period of precipitation across the region. Notice, we said “precipitation” and not “rain”. That’s because it might not all be just rain. Yup, the dreaded “S-word” is possible again. It’s a little too early to tell how likely it is, but the best chance for any accumulating snow would probably be in the higher terrain. As we head into April, it becomes tougher and tougher to get accumulating snow around here, especially during the daytime. Oh, it’s happened plenty of times, but you need things to be set up just right, and this doesn’t look to be that type of setup right now. Showers may linger around here into Sunday before high pressure starts to build in again. Right now next Monday looks partly cloudy and seasonably cool. If you have to ask why we’ve included Monday, then you’re probably not from around here.

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Opening Day should be a National Holiday. Image provided by Boston.com

Monday: Periods of rain, possibly some freezing rain well north and west of Boston in the morning. High 37-44, except 44-51 south of Boston.

Monday night: Rain tapers off in the evening, then becoming mostly cloudy with some patchy drizzle. Low 33-40.

Tuesday: Cloudy with rain and showers redeveloping. High 47-54.

Tuesday night: Cloudy with showers tapering off and ending. Low 34-41.

Wednesday: Skies may remain cloudy with some lingering drizzle or showers along the coast, becoming partly to mostly sunny well inland. High 45-52, coolest along the coast.

Thursday: Partly to mostly sunny. High 42-49, coolest along the coast.

Friday: Becoming cloudy with showers developing, possibly mixing with or changing to snow well north and west of Boston, especially at night. High 40-47.

Saturday: Breezy with rain likely, possibly mixed with snow well north and west of Boston. High 39-46.

Sunday: Cloudy skies with showers possibly lingering in eastern areas into the morning. High 46-53.

Finally, here’s something that we find this interesting, and since this is our blog, we’re going to tell you about it. There’s a tropical disturbance east-northeast of the Bahamas that is being watched for development right now. Yes, it’s March. No, it’s not unheard of, though it is fairly rare. It’s not expected to develop into a tropical system, but could become quite a gale in the North Atlantic this week.

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It’s not very often you see the tropical suite of models run for a system in the Atlantic in March. Image provided by WeatherBell.

 

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Weekly Outlook

Weekly Outlook: March 20-26, 2017

Astronomical spring starts today at 6:29am, and for part of this week, it will actually feel like Spring. Of course, that means part of the week won’t feel like Spring. Sorry to disappoint you, but the parts that don’t feel like Spring won’t feel like Summer. Yup, that means they’ll feel like Winter. It is still March after all.

The week will start off with low pressure continuing to pull away from the area and high pressure building in. That means sunshine, diminishing winds and mild temperatures. A weak front moves through tonight, bringing some clouds with it, and little more than that. Tuesday will have plenty of clouds and some sunny breaks, but it will be a few degrees warmer than Monday. We’re heading in the right direction, right? Wrong. A stronger cold front moves through Tuesday night, with a few snow showers possible. Skies quickly clear out behind it giving us plenty of sunshine on Wednesday, but it will be windy and much colder. Possibly even cold enough to set a few records. Yeah, that’s cold. High pressure builds in later Wednesday into Thursday with sunshine, diminishing winds. We start to warm up on Friday as a warm front approaches, possibly bringing a few showers with it. Whether that warm front actually makes it through or not is still not set in stone.

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Thursday morning will be chilly, with some record lows possible in the Northeast. Image provided by WeatherBell.

This brings us to next weekend. This is where things get complicated. If the warm front moves through, Temperatures on Saturday could spike into the 60s in many areas, especially if we get any sunshine. If the front doesn’t come through, we might stay in the 40s all day. For now, we’ll stay right in the middle, with upper 40s to middle 50s, but please realize that temperatures could be considerably warmer or colder than what we are forecasting at the moment. Regardless of whether the warm front moves through, a cold front will drop southward across the region later on Saturday, bringing in some showers and cooler conditions, especially if we get into the warm air. That front will stall out south of New England on Sunday while a wave of low pressure moves along it. Exactly how quickly that wave moves along the front and how far south the front stalls are key to the forecast. Right now, it looks to be a little too far south and moving a little too quickly, which means that most of the precipitation moves out before the colder air settles in. That means the rain may end as some snow on Sunday, with only a little accumulation in some spots. However, there are some models that have the front stall a little closer to the South Coast, and the wave moves through a little slower. The result is a better chance of some accumulating snow later Sunday into Monday, and for at least one model, a lot more accumulating snow. For now, we’re leaning towards the solution with little to no snow, but the potential is there for more snow across the area. If anything does materialize, we’ll let you know later in the week. For now, don’t worry about changing any plans, but just keep an eye on the forecast on the off-chance that this does become a problem.

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A few models are showing the potential for highs in the 60s on Saturday. Not all of them show this though. Image provided by WeatherBell.

Monday: Mostly sunny skies with diminishing winds. Clouds start to move in late in the day. High 44-51.

Monday night: Partly to mostly cloudy. Low 25-32.

Tuesday: Intervals of clouds and sunshine. High 47-54.

Tuesday night: Slight chance for a rain or snow shower, then clearing skies and windy. Low 25-32.

Wednesday: Becoming mostly sunny, windy, and colder. High 30-37.

Thursday: Plenty of sunshine, still breezy and cold. High 29-36.

Friday: Becoming mostly cloudy, breezy, and milder with a chance of showers. High 40-47.

Saturday: More clouds than sunshine, chance for a few showers. High 48-55.

Sunday: Partly to mostly cloudy, chance for some snow or rain showers, especially along the South Coast. High 34-41.

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Heavy Rain/Snow, Winter Weather

March Madness Has Arrived

It’s time for March Madness once again, and we’re not talking about the NCAA Basketball Tournament. No, this time we’re talking about the relentless hype ahead of a March snowstorm. You’d think that we’ve never had a big storm around here in March before with the way the media is reacting. It’s almost as if everyone has forgotten about the storms in 199319972007, and 2013, never mind the ones we’ve had in April (or May).

Well, enough about that, let’s get right to the details of the storm. Low pressure is moving across the Ohio Valley today while a second area of low pressure is starting to develop off the Southeast coast. As the Ohio Valley system weakens tonight, it will transfer its energy to the coastal storm, and then the fun really begins.

The low will move up the coastline tonight into Tuesday and rapidly strengthen. Snow will break out across the region around daybreak Tuesday, and will fall heavy at times from mid-morning into the evening. Snowfall rates of 1-3 inches per hour seem likely. The snow will be accompanied by winds gusting to 40-50 mph at times, even higher near the coast, and especially across Cape Cod. This may create blizzard conditions at times, with significant blowing and drifting snow expected. We’d recommend that you stay off the roads, as travel will be dangerous at best during the daytime hours. The good news is that the storm will be moving relatively quickly, so the snow will taper off in the evening, and end at night.

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Strong winds will accompany the storm on Tuesday across much of the region. Image provided by WeatherBell.

The big wildcard at this point is the exact track of the storm. Some of the models are trying to indicate that the storm will move across southeastern Massachusetts late in the day, while others keep the storm near or just east of Cape Cod. The farther the storm tracks to the west, the more likely a change to sleet and/or rain becomes across southeastern Mass, possibly as far inland as the I-95 corridor. Obviously, that will have a big impact on snowfall totals.

So, how much snow are we looking at? Well, many in the media have been throwing out amounts like 1-2 feet or some other ridiculous numbers. The fact is, with a storm moving as quickly as this one is (it’s only going to snow for about 12-15 hours), it’s tough to get amounts that high. Our forecast is as follows:

Cape Cod: 3-6″ on the Outer Cape and Islands, 5-10″ closer to the Canal

SE Mass/RI: 6-10″ from I-95 south and eastward, 10-16″ north and west of there.

The remainder of Central & Eastern Mass/N RI/Southern NH/southern ME: 12-18″, with isolated heavier amounts.

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GFS model forecast for snowfall through Wednesday evening. This model most closely matches our thinking for snowfall right now. Image provided by Pivotal Weather.

 

Even though the snow will be winding down Tuesday night, Wednesday won’t be a great day for cleanup. With an upper-level low moving across the region, and the storm itself getting cranked up in Atlantic Canada, it’ll be cloudy, windy, and cold, with scattered snow showers. While there shouldn’t be much additional accumulation. Another inch or two is possible in a few spots.

 

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Heavy Rain/Snow, Weekly Outlook, Winter Weather

Weekly Outlook: March 13-19, 2017

Spring is almost here. Just keep reminding yourself of that. Red Sox Opening Day is 3 weeks from today. Marathon Monday is 5 weeks from today. Before you know it, we’ll be walking around in shorts and enjoying warm weather. Got those thoughts in your head now? Good, because this week will feel like the middle of winter. In case you haven’t heard and thanks to the relentless TV and internet hype, everyone has heard, the “Storm of the Century of the Week” is going to paralyze the region for the next 6 weeks. OK, we got caught up in the hype for a second. Seriously though, we’ve got ourselves a significant snowstorm heading our way for Tuesday.

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GFS model forecast for the progression of the storm from Monday evening through Wednesday evening. Loop provided by Pivotal Weather.

 

The week starts off with the proverbial “calm before the storm” on Monday, as high pressure keeps us dry and chilly. Low pressure will be moving across the Ohio Valley while a second area of low pressure starts to take shape off the Southeast coast. As the Ohio Valley system weakens, it will transfer its energy to the coastal storm, and then things really start to happen.

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It’s gonna blow on Tuesday. The wind that is. NAM model forecast for wind gusts Tuesday afternoon. Image provided by WeatherBell.

The low will move up the coastline Monday night into Tuesday and rapidly strengthen. Snow will break out across the region towards daybreak Tuesday, and will fall heavy at times from Tuesday morning into Tuesday evening. When we say heavy, we mean HEAVY, as in 2-3 inches per hour at times. The snow will be accompanied by winds gusting to 40-50 mph at times, even higher near the coast, and especially across Cape Cod. This may create blizzard conditions at times. If you’ve got plans for Tuesday, either get there by daybreak, or wait until evening to get there, because driving won’t be fun during the daytime hours, and could be quite hazardous. The good news is that the storm will be moving relatively quickly, so the snow will taper off in the evening, and end at night. The other potential good news is that the snow will likely change to rain for a time across Cape Cod. That changeover could make it into southeastern Massachusetts as well, but how far inland is still a big question. Obviously, that will have a big impact on snowfall totals.

So, how much snow are we looking at? You’ve probably heard the apocalyptic forecasts out there of 1-2 feet, or 15-30 inches, or some other crazy ranges. The fact is, with a storm moving as quickly as this one is (it’s only going to snow for about 12-15 hours), it’s tough to get amounts that high. Our preliminary numbers are:

Cape Cod: 3-6″ on the Outer Cape and Islands, 5-10″ closer to the Canal
SE Mass: 6-12″ where it mixes with rain, 10-16″ where it doesn’t.
Southern NH/ME: 10-16″
Eastern/Central Mass: 12-18″, with some isolated heavier amounts.

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GFS model forecast for snowfall through Wednesday evening, This model most closely matches our thinking for snowfall right now. Image provided by Pivotal Weather.

Things will slowly improve on Wednesday, but with an upper-level low moving across the region, we can expect some occasional snow showers, and winds will remain quite gusty as the storm gets cranked up over Atlantic Canada. High pressure starts to build in on Thursday, but it will likely be another blustery and cold day. For the holiday on Friday (it is Evacuation Day after all), it’ll be another sunny and chilly day, but winds will start to diminish as high pressure continues to build into the region. Clouds return on Saturday, then a weak cold front moves through Saturday night, bringing some snow showers in. An upper-level low may hang around into Sunday, possibly producing more snow showers.

Monday: Plenty of sunshine to start, clouds increase during the afternoon. High 26-33.

Monday night: Becoming cloudy, snow developing towards daybreak. Low 16-23.

Tuesday: Hazy, hot and humid. Windy with snow, heavy at times. High 26-33, except 33-40 across Cape Cod.

Tuesday night: Snow tapers off and ends, winds gradually diminish. Low 15-22.

Wednesday: Partly to mostly cloudy and breezy with a few snow showers possible. High 24-31.

Thursday: A mix of sun and clouds, still breezy. High 23-30.

Friday: Partly to mostly sunny. High 28-35.

Saturday: Sunshine fades behind increasing afternoon clouds. Chance for light snow or snow showers at night. High 30-37.

Sunday: Mostly cloudy with a few snow showers possible. High 31-38.

We will have an update on the storm Monday afternoon. Hopefully, things will be a little clearer by then. Remember, spring is just around the corner. If you keep telling yourself that, you might even start to believe it.

 

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Extreme Temperatures, Heavy Rain/Snow, Winter Weather

Welcome Back Winter

It seems as though we went through this last week, but once again, after a taste of early Spring, Mother Nature is about to remind us that March can still bring plenty of wintry weather to the area.

Today is the transition day, as strong winds usher much colder air into the region behind a cold front that crossed the region late Wednesday night. While temperatures are still in the 40s, things are about to change, and most of you probably won’t like it. That cold front will stall out south of New England today, and low pressure will ride along it across the Mid-Atlantic states, passing south of us on Friday. Meanwhile, high pressure will build in north of New England, bringing plenty of cold air with it. Let’s see now, cold air moving in from the north and moisture moving in from the south. What happens when you combine those? That’s right, you get SNOW! Luckily, we’re not looking at a lot of snow this time. Let’s get to the details:

Snow should start to develop early in the morning, possibly even starting as a little rain across Cape Cod and southeastern Massachusetts. The snow may fall at a pretty good clip during the morning hours, tapering off and ending during the afternoon.Since we’re into mid-March, the sun angle is roughly the same as the end of September. In other words, fairly strong. So, once we get past sunrise, even though it’ll be cloudy, the snow will have a tougher time sticking to paved surfaces. That’s the good news. The bad news is that a lot of the snow will fall before then, so the roads may not be that pretty for the morning commute.

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Forecast from the NAM model for the progression of Friday’s storm. Loop provided by Pivotal Weather.

OK, so the snow ends in the afternoon and we’re done right? As noted college football analyst Lee Corso used to say “Not so fast my friend”. As the storm moves into the Gulf of Maine, a piece of energy, called a Norlun trough (Explained here by Matt Noyes), may produce some additional light snow from the North Shore up into southern New Hampshire and south coastal Maine through the evening hours. It won’t amount to much, but could be just enough to screw up the evening commute well north of Boston.

So, how much snow are we looking at? North of the Mass Pike, probably less than an inch, if any snow falls at all. From the North Shore into Boston and it’s immediate southern and western suburbs, probably 1-2 inches. For the South Coast, roughly south of Route 44, 2-4 inches should do it, with a little more possible across parts of the Cape and Islands.

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The High Resolution NAM model most closely matches our thinking with regards to snowfall on Friday. Image provided by WeatherBell.

All in all, not a big deal, especially by New England standards. What will be a big deal is the cold air behind the storm. Similar to last Saturday, this Saturday will be quite chilly, especially with fresh snowcover. High temperatures may struggle to get into the lower 20s, but wind chills will be in the single numbers and below zero. So, if you’re heading outside, make sure you bundle up. It’ll feel more like January than March.

Finally, we’re aware of the uncontrolled hype on the Internet (and TV) about a potentially major snowstorm on Tuesday. Right now, it’s a potential storm and nothing else. We’ll certainly keep our eyes on it, and if a threat does materialize, we’ll let you know well in advance. For now though, it’s nothing more than a figment of the computer models’ imaginations. We don’t participate in hype or speculation here at StormHQ, so we’re going to leave it at that.

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