Extreme Temperatures, Weekly Outlook, Winter Weather

Weekly Outlook: November 11-17, 2019

Thank you to all that have served or continue to serve our nation. Image provided by the United States Army

Are you ready? Ready for Winter? It’s coming, and quickly. Better enjoy today, because after that, it’s going to get cold.

We start the week off with high pressure in control, but we’ll have plenty of clouds as a cold front begins to approach the region. That front will move through on Tuesday, with some rain likely ahead of it. Low pressure will develop along this front and move right across the region on Tuesday. Ahead of the low and the front, it will be somewhat mild, but once the front moves through in the afternoon, that’s when things start to happen.

NAM model forecast showing rain coming in ahead of the cold front, changing to snow before ending behind it. Loop provided by Tropical Tidbits.

Colder air comes surging in behind the front, and temperatures will quickly drop Tuesday afternoon. Rain will likely change over to sleet and snow from northwest to southeast. Now we’re not talking about a lot of snow, probably an inch or less in most spots, and mainly on grassy surfaces, but snow will be the least of the concerns. Gusty winds will help to dry out the roads, and ground temperatures remain fairly mild, but with temperatures dropping into the 20s by late Tuesday, we could see some ice developing, especially on elevated surfaces like bridges and overpasses. So, if you’re going to be out and about Tuesday evening or night, use caution.

While there might be a pretty good snowstorm up north, around here, we’re not expecting much. Image provided by Pivotal Weather.

We’ve covered the snow potential, and the potential for slick roads, but here’s the biggest issue we’ll be dealing with – it’s going to be cold. When we say “cold”, we mean “COLD”. As in, record low temperatures Wednesday morning across most of the region. As in wind chills (another phrase most of you don’t like) in the single numbers (Fahrenheit, not Celsius). Yeah, it’s going to feel like January Tuesday night into Wednesday. Oh yeah, we forgot to mention that Wednesday may see highs in the 20s to lower 30s.

Any location that is circled is likely to set a record low temperatures Wednesday morning. Yeah, it’s going to be cold. Image provided by Weathermodels.com

Winds will diminish for Thursday, but it will remain chilly. Temperatures should start to moderate a little on Friday as high pressure slides offshore. Of course, another cold front comes through Friday night and then we get cold again next weekend, but probably not quite as cold as Tuesday night and Wednesday. Temperatures will still be well below normal.

Wind chills will be in the single numbers when most of you wake up Wednesday morning. Image provided by WeatherBell.

Monday: Mostly cloudy with a few showers possible, mainly north of the Mass Pike. High 41-48 north and west of Boston, 49-56 south of Boston.

Monday night: Cloudy with showers developing late at night. Evening low 34-41 north and west of Boston, 42-49 south of Boston. Temperatures may rise after midnight

Tuesday: Cloudy and breezy with showers likely, changing to sleet and snow during the afternoon. Morning high 42-49 north and west of Boston, 50-57 south of Boston, then temperatures quickly drop in the afternoon.

GFS forecast for temperatures starting at midnight tonight and ending at 7am Wednesday. Loop provided by WeatherBell.

Tuesday night: Any lingering snow showers end in the evening, then clearing, breezy, and colder. Low 13-20.

Wednesday: Sunny, breezy, and cold. High 25-32.

Thursday: Intervals of clouds and sun, a few flurries are possible at night. High 34-41.

Friday: Sunshine to start, then clouds move in during the afternoon. High 43-50.

Saturday: Sunshine and some afternoon clouds. High 31-38.

Sunday: A mix of sun and clouds. High 37-44.

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Extreme Temperatures, Heavy Rain/Snow, Winter Weather

Boston May Need an Ark, Bismarck Needs a Plow

Two developing storm systems – one off the East Coast and one in Plains, will both wreak havoc in the next few days, but for very different reasons.

Two low pressure areas are developing off the East Coast early this morning. The northern system is the stronger of the two, but the southern one is being monitored by the National Hurricane Center. It has the potential to develop into a tropical depression or subtropical storm later today. Whether it does or not, these two low pressure areas will eventually merge and become a rather strong non-tropical system over the next 24 hours. There is very little in the way of steering currents right now, so the system will just meander around off the coast until Saturday.

Low pressure won’t be in a hurry to go anywhere off the East Coast for the next few days. Loop provided by Tropical Tidbits.

As the system drifts northward, it will produce gusty winds along the coast, especially in New England. Tides are astronomically low at the moment, but will be rising later this week, so coastal flooding, while not a major concern, will still be possible in some locations. A coastal flood watch has been issued for parts of Plymouth County, Cape Cod, and Martha’s Vineyard. Rough seas will also be a large concern for marine interests, with Storm Warnings now in effect offshore. However, the biggest concern and also the biggest question mark right now is heavy rainfall.

Wind gusts in excess of 50 mph are possible across much of Southern New England. Yeah, that blows. Image provided by WeatherBell.

While the storm will likely spread some heavy rainfall into New England, there is still plenty of uncertainty as to how far north the heavy rain gets, as well as how much rain actually falls. Some of the models are producing extremely heavy rainfall, with totals in excess of 10″ in southeastern Massachusetts! While we aren’t buying the extreme totals, the fact that most of the models are showing this potential means that some very heavy rain is likely, especially south of Boston, where a Flood Watch has been issued.

That’s a lot of water coming out of the sky over the next 3 days. Some models have even more than this! Image provided by WeatherBell.

Thanks to some dry weather over the past couple of months, we shouldn’t have to worry about any flash flooding, though downpours will result in ponding of water on roadways, and some locations normally prone to flooding in heavy rain will also have problems. However, since we’re expecting a prolonged period of heavy rain, flooding is still a possibility in some locations, other than the ones we just mentioned, especially some of the smaller streams and rivers. Strong winds will also start to take some of the leaves off of trees, which may clog up storm drains, resulting in some flooding as well.

Recent dryness means that flash flooding is not likely in New England with this storm. Image provided the the Northeast River Forecast Center.

While all this is taking place off the East Coast, some very cold air will settle into the Rockies and Plains states as low pressure starts to develop across the Central Plains. Record lows are likely to be set in numerous locations over the next few mornings across the region. This system will head north-northeastward while strengthening. The system isn’t expected to become that strong, but with a large high pressure area building in behind it, it will produce some strong winds. It will also draw warm and moist air northward from the Gulf of Mexico. As this air runs into the much colder air on the backside of the storm, the first significant snowstorm of the season is expected to develop across the Northern Plains.

Winter Storm Watches and warnings have been posted from parts of Idaho Montana, and Wyoming into parts of northern Nebraska and the Dakotas as well as northwestern Minnesota. across Idaho, Montana, and Wyoming, snowfall totals of 6-12 inches are possible, with some heavier amounts in the higher elevations. The biggest issues are expected across the Dakotas and northwestern Minnesota.

Wind gusts of 40-50 mph or more are expected across the Northern Plains. Image provided by WeatherBell.

The precipitation will start as rain across this area later today, but strong northerly winds will usher much colder weather in, changing the rain to snow from west to east on Thursday. Like its East Coast counterpart, this storm won’t move at a rapid pace, so snow, possibly heavy at times will continue across this area into early Saturday, with snow showers lingering into Sunday.

This storm also has some questions with it’s precipitation shield. While heavy snow is likely across a large area, how much falls and where the heaviest snow will fall is still a question. Right now, it looks like the heaviest snow will fall from central South Dakota into central and eastern North Dakota, but that still could change. As for amounts, many areas could see more than a foot, with totals in excess of 2 feet possible in some areas. The snow will be accompanied by winds gusting to 40-50 mph, resulting in blizzard conditions, especially late Thursday into Friday.

Welcome to winter! Snowfall totals of 1-2 feet or more are possible across the Dakotas. Image provided by Pivotal Weather.

While snow in October is not unusual across this region, snowfall amounts of this magnitude this early in the year are extraordinarily rare. In Grand Forks, ND, the largest October snowstorm on record occurred October 24-26, 2001, and it dropped 10.9″ on the city. In Fargo, ND, the largest October snowstorm on record is only 8.1″ on October 30-31, 1951. For Pierre, SD, the October snowstorm of record occurred October 30-31, 1943, and it only produce 7.2″ of snow. Current model forecasts are forecasting amounts that are 3-4 times the records. These model forecasts are likely too high, but it seems likely that many of these October records are going to be obliterated in the next few days. Hopefully, this is not a sign of what’s to come this winter.

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Extreme Temperatures, Weekly Outlook, Winter Weather

Weekly Outlook: March 4-10, 2019

The first full week of March is shaping up to be a wintry one, mainly in the temperature department, but a little in the precipitation department as well.

The snow will be ending across the region this morning as our storm system pulls away, with some clearing this afternoon. Temperatures may even get a tad mild, allowing for some melting to take place. However, we’re going to drop back below freezing tonight, so anything that melted with ice back up. If you’re heading out this evening, watch out for slippery conditions on untreated surfaces.

Temperatures could get into the middle to upper 30s this afternoon, allowing some of the fresh snow to melt. Image provided by WeatherBell.

After that, a rather cold airmass will settle into the region for Tuesday through Thursday. While temperatures won’t be as extreme as in the Plains states, we’re still looking at temperatures that are 10-20 degrees below normal, especially Wednesday and Thursday. A couple of upper-level disturbances will also be moving through the region, which may produce a few snow showers at times, especially Wednesday and Thursday.

Temperatures will be 10-20 degrees below normal during the middle of the week. Image provided by Weathermodels.com

By Friday, high pressure will move offshore and temperatures will start to moderate. That just means it won’t be quite as cold, but temperatures will still be below normal. The weekend is where things get complicated.

It looks like we’re going to have 2 systems impact the area, a weak one on Saturday, and a stronger one on Saturday. Given that these are both several days away, nothing is set in stone at this point. The first system passes south of New England on Saturday. There is at least one model that has it pass too far south to have any impact on us, but most bring it close enough to spread in some light precipitation. Right now, it looks likely mainly some light snow, but it could be some rain as well, especially along the south coast.

The stronger storm comes in on Sunday. This one looks like it will produce some rain across the area. However, some models are showing temperatures below freezing at the start, which means we’d be looking at yet another situation where we have snow to sleet or freezing rain inland and rain along the coast. Again, this is a week away, so trying to nail down details at this point is a futile exercise. Just be aware that next Sunday could be messy, especially north and west of Boston.

Daylight Saving Time starts at 2am Sunday. Sunset next Sunday evening will be at approximately 6:45pm. Image provided by the National Weather Service.

Monday: Snow (rain on the Cape) ending early, some sunny breaks develop in the afternoon. High 33-40.

Monday night: Becoming mostly clear. Low 9-16.

Tuesday: Morning sunshine, afternoon clouds, slight chance for a snow flurry. High 24-31.

Tuesday night: Clear to partly cloudy. Low 10-17.

Wednesday: A sunny start, then clouding up again, breezy. A snow shower is possible. High 19-26.

Thursday: Intervals of clouds and sunshine, with a few afternoon snow showers possible. High 20-27.

Friday: Plenty of clouds. Light snow or rain developing at night. High 28-35.

Saturday: Cloudy with some snow or rain showers possible in the morning. High 31-38.

Sunday: Cloudy with a chance of rain, possibly some snow or a wintry mix across the interior. High 34-41.

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Heavy Rain/Snow, Winter Weather

Sunday Night Special or Monday Morning Madness?

As promised, the second storm in our one-two punch is heading this way. While most of the snow is expected while you’re asleep Sunday night, it could have a big impact on your Monday morning commute.

Winter Storm Warnings and Winter Weather Advisories are in effect for most of the Northeast as of Sunday morning. Image provided by Pivotal Weather.

High pressure is hanging on this morning, providing us with sunshine, but clouds will quickly move in this afternoon as low pressure starts to move towards the Mid-Atlantic coastline, passing south of New England Monday morning. This storm will be a bit stronger than the one we had yesterday, and also have a little more moisture to work with, but will be moving fairly quickly, limiting the amount of time it spends in the region. One thing working in its favor is that most of the snow will fall at night. We’re at the time of year where the sun angle is high enough that snowfall during the daytime has a hard time sticking on pavement. At night, that’s not an issue.

The high-resolution NAM model shows the snow moving in this evening, becoming heavy overnight, and ending in the morning, with any rain confined to the south coast. Loop provided by Tropical Tidbits.

Snow will move in this evening, likely in the 7-10pm time frame, and will continue through the overnight hours. It may be heavy at times, especially between about 1 and 5am. A change to rain is expected for Cape Cod and the South Coast, but likely won’t advance past Route 44. Everything should wind down and end around 6-8am. That’s also the time of the morning commute. Road crews should have plenty of time to work on getting the roads cleared, but given past experience, and that people will likely leave early since it’ll still be snowing, we expect many roads to still be in awful shape. Give your self a lot of extra time in the morning. We also expect many school districts to cancel classes for Monday.

Snowfall is running about 10-20 inches below normal across the area this winter. Image provided by the Northeast Regional Climate Center.

It’s been a down year for snowfall, running 10-20 inches below normal across the area, but this storm will put a dent in those departure numbers. How much are we looking at?

Cape Cod/South Coast/Southern RI: 2-5″
The rest of the region: 4-8″ with isolated 10″ totals possible, especially from northern RI into the South Shore.

The high-resolution NAM has had a great winter for snowfall predictions, and we’re not straying from it again. Image provided by WeatherBell.

Things look to quiet down and get colder behind this storm, but a pattern change to milder weather could be coming as we head towards mid-March. We’ll have more details on at least the next week in our Weekly Outlook early Monday morning.

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Heavy Rain/Snow, Winter Weather

Not One, But Two Storms on the Way

Back in our Weekly Outlook on Monday, we warned you that even though Meteorological Winter ends on February 28, that March can still be a wintry month. Well, today is March 1, and we’re looking at two snowstorms in the first four days of the month.

You can see that this is a fairly fast-moving storm. In by daybreak Saturday, out before dinnertime. Loop provided by Tropical Tidbits.

Technically, there’s actually 3 storms, as the first one is passing south of the region this morning. It brought in some clouds, and a few stray flakes across southeastern Massachusetts, but otherwise, had little impact on us. The first storm we need to pay attention to is moving across the central Appalachians this afternoon. It will move off the Mid-Atlantic coast tonight, then pass south of New England on Saturday. A few days ago, it looked like this storm would pass harmlessly to our south while a a system to the north brought in some snow or rain later on Saturday. Well, this storm became the more dominant of the two, and will pass closer to us than originally thought.

Snow will develop Saturday morning, maybe before daybreak south of Boston. It may even start as some sleet or rain across Cape Cod before changing to snow It will snow steadily during the morning hours, and then taper off and end during the afternoon, possibly lingering along the coast until evening. Despite the hype from some of the media, this will not be a big storm. Oh sure, it’ll be disruptive to your Saturday morning/afternoon plans, but it’s not a major storm.

So, the big question – how much?

Central NH/Southern ME (Concord/Portland) – Less than 1″
Southern NH/Seacoast/Cape Cod (Manchester/Nashua/Portsmouth) – 1-2″
Merrimack Valley – 2-4″
Metro Boston/MetroWest/Southeastern MA/ Rhode Island – 3-6″

Would be we shocked if a few spots, especially south of Boston, pick up 7 or 8 inches? Nope, not at all. This won’t be the fluffy snow we had a few days ago, so it won’t pile up as quickly.

We’ve stuck with the high-resolution NAM for most of the winter and it’s served us well, so we’re going to do it again. Image provided by Weathermodels.com

OK, so the snow ends Saturday afternoon/evening, and we’re all set, right? Nope – the next storm, follows fairly quickly for Sunday night and Monday. This one looks a little strong, and will pass a little closer. This will allow for the rain/snow line to penetrate a little farther into southeastern Massachusetts. However, with it being a stronger storm, it will have more moisture to work with, and that means more snow. There’s still many details that need to be worked out, and some things will depend on what the first storm does, so we’re not going to go into too much detail yet. We’ll have another blog post Sunday morning focused on that storm. But, there are several models showing the potential for up to, or even more than a foot of snow in spots from that storm.

The NAM model indicates that we could get a pretty good wallop early Monday. We’ll see if things stay that way over the next day or two. Image provided by Pivotal Weather.

After that storm goes by, it looks cold and dry for a few days. But let’s take it one storm at a time for now. Look for an update from us Sunday morning.

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Winter Weather

A Little Snow to End February

As the headline implies, we’ve got some of the flaky white stuff on the way. This storm is going to be unlike any storm we’ve had all winter. It’s going to be all snow, and the fluffy type at that. It also, may cause problems for your Thursday morning drive to work or school.

High pressure is in place right now, with a cold and dry airmass settled into New England. Temperatures dropped into the single numbers and teens this morning, and at midday, dewpoints were still well below zero. As the high moves off the east, an Alberta Clipper will move in from the west. As it starts to spread precipitation into the region, it will run into this dry air this evening. So, even though the radar may show snow falling, it will evaporate before it hits the ground.

Very dry air remains in place at midday. This will help delay the snow’s arrival a little this evening. Image provided by WeatherBell.

Eventually, the atmosphere will moisten up enough so that the snow will make it down to the ground, and we’ll have some light fluffy snow falling through the overnight hours. It should taper off and end from the west to east right around the time most people head out to work or school in the morning. Road crews should have plenty of time to work on the getting everything cleared before the morning rush hour, but this being New England, where plenty of people completely forget how to drive as soon as they see a single raindrop, well, the snow will probably impact your morning drive, so leave a little extra time.

As for how much will fall, this won’t be a big deal, at least by New England standards. Most of the snow maps you see people post online (like the one below) assume a 10:1 ratio for snow to liquid. In many cases, this will work – 1 inch of rain equates to 10 inches of snow. However, the colder you get, the more the ratio changes. With temperatures in the teens, the ratio could be 20:1. For tonight’s storm, the ratio will probably end up somewhere around 15:1, so, you might expect a little more than the map below is showing. Remember – I also said that the initial burst of snow will likely evaporate before reaching the ground. The model assumes that anything showing up as precipitation does reach the ground, so it will assume we’ve got more precipitation than we actually will get. Plus, nearly every storm this winter has underperformed in the snow department, compared to what the models have forecast. So, factoring all that in, the 10:1 map may actually not be that bad after all.

OK, enough of the caveats and explanations, all you want to know is how much you’ll be cleaning off of your car or driveway in the morning.

Southern New Hampshire: 1-2″
Merrimack Valley/North Shore/Cape Cod/South Coast/Rhode Island: 1-3″
Metro Boston/MetroWest/South Shore: 2-4″

Given the fluffy nature of the snow, if a few places picked up 5″, especially from Worcester County into the South Shore, we wouldn’t be completely shocked.

We’ve been going with the High-resolution NAM all year, no reason not too once again. Image provided by Weathermodels.com

Another weak system will pass to our south Thursday night into Friday morning, with some light snow possible across the South Coast and Cape Cod, but the storm may end up too far south to impact us at all. Another system passes to the north late Saturday into early Sunday, and this one will be more typical of what we’ve seen this winter, with some light snow changing to sleet, freezing rain and eventually rain. What we’ve actually got our eyes on in the future is Sunday night and Monday. The models have been signalling for a few days the potential for a system to impact us then, but the details have been all over the place. The various models have shown solutions that range from a complete miss to snow to rain, to a heavy snowstorm. There’s still plenty of time for that to come into focus, and we’ll worry about it more as the weekend arrives. For now, we’ll just deal with the light snow tonight.

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Weekly Outlook, Winter Weather

Weekly Outlook: February 18-24, 2019

You’re waking up to snow this morning, but that might not be the only snow for the week, at least for most of us. It is still February, so this should be expected.

The week is starting off with some snow, but since we discussed that in detail yesterday, and the bulk of the snow will be over by the time most of you read this, we won’t dwell on it much longer. Snow showers will continue into the afternoon, but little additional accumulation is expected. High pressure then builds in for tonight, Tuesday and part of Wednesday. This will give us drier but colder conditions. Again, it is February, this should be expected.

It’s still winter, so it shouldn’t be that warm. Average high temperatures for mid-February are in the upper 30s to lower 40s. Image provided by Weathermodels.com

By late Wednesday, another low pressure system will head towards the Great Lakes, just like a lot of them have already done so far this winter. As a result, we’ll see the same thing we have already seen plenty of times. Snow will develop Wednesday night, then warmer air will move in aloft, with a change to sleet and/or freezing rain early Thursday, and an eventual change to all rain as warmer air finally moves in at the surface. This doesn’t look like a big deal, with an inch or two of accumulation possible Wednesday night from the Merrimack Valley into southern New Hampshire.

A little bit of snow is expected early Thursday morning, mainly north of Boston. Image provided by Pivotal Weather.

The rain ends Thursday morning, then high pressure returns for later Thursday into Friday and Saturday. Then on Sunday, we do it all over again. Low pressure heads towards the Great Lakes again, and we get some snow, changing to sleet and/or freezing rain, then plain rain. Wash, rinse, repeat.

Monday: Cloudy with occasional snow showers tapering off and ending. High 27-34.

Monday night: Clearing. Low 9-16.

Tuesday: Partly to mostly sunny. High 24-31.

Tuesday night: Becoming partly to mostly cloudy. Low 9-16.

Wednesday: Cloudy with snow developing in the evening, changing to sleet, freezing rain, and rain from south to north overnight. High 25-32.

Thursday: Rain ending in the morning, then becoming partly sunny and breezy in the afternoon. High 42-49.

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

Saturday: Some early sun, then becoming mostly cloudy. High 37-44.

Sunday: Cloudy, snow developing, quickly changing to sleet or freezing rain, then plain rain in the afternoon. High 40-47.

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