Weekly Outlook

Weekly Outlook: February 26-March 4, 2018

Yup, the hype train has left the station again and is rolling down the track. You may have heard that there’s a storm coming later this week. We’ll set the record straight between hype and reality, fact and fiction, in this outlook.

The first half of the week, also known as the last 3 days of February (and the last 3 days of meteorological winter) will actually be quite pleasant. High pressure will be in control with sunshine and mild temperatures. It’s not the early taste of spring that we had a week ago, but we doubt there will be many complaints. After that, things start to get complicated.

GEFS Ensembles North America 500 hPa Height 120

By the end of the week, a “blocking” pattern will set up. The large upper-level high pressure area over Greenland will slow down the progression of storms eastward across the Eastern U.S. Image provided by Weathermodels.com

A “blocking” pattern will set up across the Eastern US. Normally, the jet stream flows west to east, steering storms across the country. When there’s a dip in the jet stream (a trough), we tend to have colder than normal temperatures, along with stormier conditions. We’ll have one of those troughs move into the East later this week, and it will eventually break off from the jet stream (called a “cut-off low”). At the same time, a large upper-level high pressure area will set up shop over Greenland. This will block the eastward progression of storms, meaning that the storm we’re expecting later this week won’t be in a hurry to leave. However, it could also be a good thing. How? If the ridge of high pressure continues to build in, it could deflect that storm farther to the south. Good for us, but bad for places like New York City, Philadelphia, or even Washington.

gfs-ememb_lowlocs_eus_21

The GFS Ensemble forecast for Friday evening shows the wide range in possible solutions. The mean solution is for a 987mb low centered east of Virginia Beach and south of Nantucket. The red numbers are the locations of the various ensemble members and their strength in millibars (add a 9, so 74 is really 974mb). Image provided by Tropical Tidbits.

The models still haven’t come to a consensus on what will happen for the end of the week. There are several things that we need to figure out before we can come up with a forecast that we’ll have any confidence in. What are those factors? Where will the low pressure area track? How strong will it be? How much cold air will be in place before the storm arrives and when it’s impacting the region? How strong will that high pressure area to the north be?  These details will likely take a few more days to be resolved. So, if you hear others, especially in the media, talking about the “3-day storm” or the “snowstorm” that will impact us later this week, take it with a giant grain of salt. Nobody, including us, can say with any degree of confidence, what will happen. We could have heavy rain, heavy snow, strong winds, or all of the above. The only thing we can be reasonably confident about is the fact that some coastal flooding seems likely. The highest tides of the month are expected at the end of the week, and with a storm of some sort off the East Coast, that will likely lead to some coastal flooding across parts of the area. Things should start to improve over the weekend, but even that will depend on the progression of the storm.

gfs_mslp_uv10g_boston_20

The potential exists for wind gusts of 30-60 mph across the region from the storm, especially along the coast, with even stronger winds across Cape Cod and the Islands. Image provided by WeatherBell.

Monday: Early clouds, then becoming mostly sunny and mild. High 47-54.

Monday night: Clear skies. Low 26-33.

Tuesday: Plenty of sunshine. High 46-53.

Tuesday night: Clear to partly cloudy. Low 31-38.

Wednesday: Some early sun, then clouds filter in as the day goes on. High 52-59.

Thursday: Mostly cloudy and becoming breezy with some rain or snow possible late in the day and at night. High 46-53.

Friday: Windy with rain or snow possible. High 35-42.

Saturday: Windy with a chance for more rain or snow, especially early. High 36-43.

Sunday: More clouds than sun, breezy, chance for a few snow or rain showers. High 35-42.

Standard
Weekly Outlook

Weekly Outlook: February 19-25, 2018

70 degrees. In July, that’s a chilly high temperature. In February, it’s a record breaker. We’re going to be challenging and possibly breaking some records this week. Don’t get too used to it though, as our early taste of Spring will be short-lived.

gfs_z500_mslp_atl_11

With a ridge of high pressure aloft along the East Coast and a Bermuda High at the surface, we’re looking at a couple of mild days Tuesday and Wednesday. Image provided by Tropical Tidbits.

The week starts out with a warm front moving towards the region, spreading in some clouds, and eventually showers on Monday. The front moves through Monday night, then a Bermuda High sets up shop for a couple of days, with unseasonably mild conditions expected for Tuesday and especially Wednesday. How mild? Most locations should reach the upper 50s to middle 60s on Tuesday. On Wednesday, most places should get into the 60s, with some lower 70s possible, especially north and west of Boston. Of course, there is an exception. Along the South Coast, the southwest winds that will bring warmer air in for the rest of us will be blowing in off of water that is still in the 30s. So, these locations will likely stay in the upper 40s and 50s both days. Still nice, but it’s not 60s and 70s.

Record0221

Record High Temperatures across the region for Wednesday February 21. It’s a safe bet that many of these records will fall. Data provided by the Northeast Regional Climate Center. For a complete list of the cities on this map with the record high data, open this PDF file.

A cold front moves through Wednesday night, bringing a few showers with it, but also bringing an end to the mild weather. Showers may linger along the south coast into early Thursday before the front pushes offshore, then high pressure builds in from the north with much cooler conditions for Thursday and Friday. Of course, “much cooler” is relative, as these temperatures will still be near to a little above normal for late February. Another storm system then moves in from the west, with some precipitation likely late Friday into Saturday. It should fall mostly as rain, but a period of snow or freezing rain is possible, especially across the Merrimack Valley and southern New Hampshire Friday night into Saturday. We’ll keep an eye on this situation as the week goes on. Another system quickly follows with more rain or snow on Sunday.

gfs_ptype_slp_boston_22

At least one model (in this case the GFS) is showing the potential for a wintry mix Friday night as a storm system moves through. Image provided by WeatherBell.

Monday: Becoming mostly cloudy and breezy with showers possible late in the day. High 42-49.

Monday night: Showers likely in the evening, otherwise mostly cloudy and breezy. Low 39-46 in the evening, then temperatures rise overnight.

Tuesday: Becoming partly sunny, breezy, and milder. High 57-64, except 49-56 along the South Coast and across Cape Cod.

Tuesday night: Partly to mostly cloudy. Low 46-53.

Wednesday: Partly sunny, breezy, and warm. Showers possible at night. High 65-72, except 49-64 along the South Coast and across Cape Cod.

Thursday: Clouds gradually giving way to some sunshine late in the day, turning much cooler. High 41-48.

Friday: A sunny start, then clouds return. Showers likely at night, possibly starting as some snow or freezing rain in the Merrimack Valley and Southern New Hampshire. High 37-44.

Saturday: Mostly cloudy and turning milder with a chance of showers, possibly some wintry mix early in the day across southern New Hampshire. High 47-54.

Sunday: Cloudy and breezy with a chance of rain or snow. High 36-43.

 

Standard
Extreme Temperatures, Heavy Rain/Snow, Winter Weather

A Saturday Night Special

The last few days have been fairly mild around here, and even milder air is coming in for the first half of the upcoming week. So naturally, we’re talking about a snowstorm for tonight.

Low pressure is over the Tennessee Valley at midday, and will quickly move towards the Mid-Atlantic coastline this evening, passing south of New England as it intensifies tonight. Even though the sun is shining now, clouds will quickly move in this afternoon, with snow developing late this evening, around 9pm or so, give or take an hour. Snow will continue overnight, with the possibility for some briefly moderate to heavy snow. Since most of you will be sleeping, this shouldn’t cause too many problems. A change to rain seems likely across parts of Cape Cod and the Islands, possibly even into extreme southeastern Massachusetts.

namconus_ref_frzn_neus_fh6-30

Forecast for the progression of the storm based on the NAM model. Loops provided by Tropical Tidbits.

Everything winds down near or a little after daybreak. For most of us, a general 3 to 5 inches of snow is expected, with a few spots possibly seeing 6 or 7 inches. Across Cape Cod, where a change to rain is likely, amounts of 1 to 3 inches seem more plausible at this time.

nam_3hr_snow_acc_boston_9

The NAM model is probably closest to our thinking for snowfall totals with this storm. Image provided by WeatherBell.

The snow won’t last too long though. The sun will return Sunday afternoon, with temperatures getting up into the 40s. That will help to quickly melt a lot of what fell overnight. Temperatures will drop back below freezing Sunday night, so things may ice up once again. Use caution if you’re heading out for anything. Even warmer weather is heading in for the start of the week. A warm front will move through on Monday, with some showers preceding the front late in the day. Once the front moves through, unseasonably warm conditions are expected for Tuesday and especially Wednesday. On Tuesday, high temperatures should get into the upper 50s and 60s away from the South Coast. On Wednesday, we could challenge some record highs, with some places possibly making a run at 70 degrees. A cold front will move through late in the day on Wednesday, bringing an end to the warm weather, so enjoy the early taste of Spring while it’s here.

GFS 50-STATES USA Mass & CT & RI 2-m Maximum Temperature 105

Yes, temperatures could reach or exceed 70 in parts of the region on Wednesday. Image provided by Weathermodels.com

Standard
Weekly Outlook

Weekly Outlook: February 12-18, 2018

Arctic Outbreaks. Blizzards. Sub-zero wind chills. These things are common around here in the month of February. None of them will be in the forecast this week. In fact, this week will be rather quiet and, believe it or not, mild (for the most part).

The week starts off with a cold front pushing offshore and high pressure building into the Northeast. Any lingering showers will end in the morning, but skies will only gradually clear out. Monday night and Tuesday will be clear and chilly as the high settles in. As the high moves offshore, milder conditions are expected on Wednesday, but clouds will also start to move in as a cold front starts to slowly approach from the west. Thursday will be a cloudy and mild day, with a few showers possible. The front finally pushes through on Friday with some rain and cooler conditions expected. High pressure returns for the weekend with dry and cooler conditions once again.

snku_acc.us_ne

Snowfall forecast from the GFS model between late Sunday night and next Sunday night. Notice that except for the Berkshires, no snow is forecast across Southern New England. Image provided by Pivotal Weather.

Monday: Some lingering showers near the South Coast early in the day, otherwise cloudy in the morning, with clearing in the afternoon. High 40-47, except for southeastern Massachusetts and Cape Cod where temperatures will start the day 48-55 then drop.

Monday night: Becoming mostly clear. Low 16-23.

Tuesday: Plenty of sunshine, clouds start to move back in late in the day. High 29-36.

Tuesday night: Partly to mostly cloudy. Low 21-28.

Wednesday: Early clouds, then becoming partly to mostly sunny and milder. High 41-48.

Thursday: Chance for some showers early, otherwise partly to mostly cloudy and mild. High 52-59.

Friday: Some morning showers, then gradual clearing, breezy, and turning cooler. High 46-53 early, then temperatures drop in the afternoon.

Saturday: Sunshine and some afternoon clouds. High 29-36.

Sunday: Mostly sunny. High 40-47.

JetBluePark

It’s a little less than 1500 miles to Fort Myers, but it’ll feel like Spring around here this week as pitchers and catchers report to Spring Training. Image provided by Redsox.com

While it won’t be in the 80s around here this week like it will in Fort Myers, pitchers and catchers report tomorrow. Spring training has arrived, which means we’re that much closer to the end of winter. That doesn’t mean we’re done with snow, but we’re getting there. Don’t forget about the Bruins and Celtics too, and, we’re also less than 3 weeks away from the start of the season for the Revolution.

If you are looking for other signs of Spring, take the following with a grain of salt, but both the GFS and ECMWF models are showing next Tuesday to be a mild day ahead of a cold front. We’re not ready to jump on board with that forecast yet, since it’s still 8 days, but it certainly looks nice. How nice? We’ll let the GFS map do the talking:

GFS 50-STATES USA Mass & CT & RI 2-m Maximum Temperature 216

GFS model forecast for high temperatures across the region on Tuesday February 20. Don’t get your hopes up just yet, it’s still 8 days away and a lot can change between now and then. Image provided by Weathermodels.com

 

Standard
Heavy Rain/Snow, Winter Weather

A Messy Wednesday On The Way

While some of you saw a few snowflakes this morning, there’s a lot more on the way tomorrow, and it’s going to make a mess of your afternoon commute.

gfs.prateptype_cat.us_ne.2018020612-loop

GFS forecast for the progression of Wednesday’s storm system. Loop provided by Pivotal Weather.

 

Low pressure will move out of the Tennessee Valley tonight, and head towards Southern New England. With high pressure over Atlantic Canada, we’ll have some cold air in place to start the day before the clouds quickly fill in by daybreak. When the precipitation moves in around midday, it should start as snow for most of us. However, it’s not going to stay that way.

Warmer air will move in off the Atlantic, quickly changing the snow over to rain across Cape Cod, with little to no accumulation. The changeover will also take place by early to mid-afternoon across southeastern Massachusetts. In these locations, mainly south and east of Interstate 95, accumulations of 1-3 inches are expected before it goes to rain. Farther to the north and west, things get a little more complicated.

NWS NDFD 2.5-km Mass & CT & RI 2-m Daily High T 2

Temperatures may not get above freezing north and west of Boston on Wednesday, meaning freezing rain could be a threat for some areas. Image provided by Weathermodels.com

That warmer air may not penetrate much farther inland than I-95 at the surface, but aloft, it probably will. When you’ve got below-freezing air at the surface and above-freezing air aloft, you get freezing rain (or sleet) – something we’ve already dealt with several times this winter. While many of the models are trying to send temperatures into the middle to upper 30s, we’re not buying it. The models almost always try to move warm air in too quickly, so we’re ignoring them. We do expect a change to freezing rain from the I-95 corridor up into the Merrimack Valley during the afternoon and evening, which will limit snowfall accumulations a bit, but also drop a layer of ice on top of everything, potentially making even more of a mess of the afternoon rush hour. For these areas, we’re expecting snowfall totals of 2-4 inches closer to I-95, and 3-6 inches up into the Merrimack Valley, as well as over towards the Seacoast of New Hampshire.

Farther inland, across interior southern New Hampshire, there are fewer questions, but everything isn’t set in stone just yet. Some freezing rain is possible, especially along the MA/NH border (including places like Salem, Nashua, and Manchester), but we’re not completely convinced that it will happen. This is something that really can’t be determined until the storm is ongoing and we see how far northward that warm air penetrates. For now, we’re allowing for this possibility, and conservatively forecasting 4-8 inches of snow. If there is no changeover, and the precipitation stays all snow, then amounts could be a bit higher, with totals of 6-10 inches becoming more common. Once you get north of Manchester, from Concord up into the Lakes Region, snowfall totals of 8-12 inches should be the norm.

nam_3hr_snow_acc_boston_15

While we don’t agree with how it arrives at these numbers, the snowfall totals from the NAM are closest to what we are thinking. Image provided by WeatherBell.

The snow will come down heavy at times during the afternoon across the region, tapering off during the evening. It looks like places that change to freezing rain or rain should go back over to snow at night before everything finally winds down and ends around midnight, give or take an hour. We’re not expecting much additional accumulation once it changes back to snow, but some places could pick up a half an inch to an inch.

NAM-WRF 3-km Mass & CT & RI 2-m Temperature 56

Temperatures will stay below freezing all day Thursday, so make sure you get the driveway cleared quickly, or you’ll need some skates to get to your car or mailbox. Image provided by Weathermodels.com

Colder air will settle in behind the storm for Thursday and Friday, so anything that you haven’t cleaned up will freeze solid Thursday morning. Another weak system may bring in some light snow Friday and Friday night, but as of right now, we’re not expecting much accumulation from that system.

Standard
Weekly Outlook

Weekly Outlook: February 5-11, 2018

Sure, that wasn’t the outcome that most of us wanted, but cheer up – there’s snow on the way! Wait, that doesn’t make you feel better? Well, before you know it, Spring will be here. After all, today is Truck Day, and pitchers and catchers report to Fort Myers a week from tomorrow. Does that make you feel better?

IMG_1800

The first sign of spring is upon us – today is Red Sox Truck Day, when all of the equipment gets loaded up and shipped down to Fort Myers for spring training. Image provided by Boston.com

The week will actually start off with a couple of dry but chilly days. The system that brought us some rain Sunday night will pull away, and high pressure builds in for Monday with sunshine and cold temperatures. Tuesday will be another chilly day, but the sunshine will be replaced by clouds as low pressure approaches from the southwest. Since the pressure over us today and Tuesday will be moving into Atlantic Canada, it won’t be in an ideal spot to keep the cold air locked into place on Wednesday, meaning that we’ll be dealing with a rain/snow line. Snow will spread across the area during the day on Wednesday, but the question is – how far inland does the rain/snow line penetrate? There’s plenty of disagreement between the models, so we’ll likely have a special blog post about this later on Tuesday, as the details should be more clear by then (we hope). Right now, we’re thinking that the rain/snow line gets to at least I-95, possibly all the way to I-495. Where it stays all snow, we’re talking plowable snow, likely in excess of 6 inches. The best chance for that will be in southern New Hampshire. Elsewhere, some accumulation is expected, with the amounts dependent on how quickly a change to rain occurs, if it occurs at all.

gfs.prateptype_cat.us_ne.2018020500-loop

The GFS tries to bring the rain/snow line into the Merrimack Valley with the mid-week storm. Other models have different ideas as to how far inland the changeover happens. Loop provided by Pivotal Weather.

Everything changes back to snow before ending Thursday morning, then high pressure builds back in later on Thursday. However, a quick-moving system spreads clouds back in on Friday, with a little bit of light snow Friday night into Saturday morning. Another system quickly follows for Sunday. Right now, this one looks to be warmer, with mostly rain across the region, however, it’s a week away, and a lot can change between now and then. We wouldn’t be surprised at all if the models trend colder, and that system ends up as more of a snow threat than it currently looks like. We’ll worry about that one later in the week.

cut

Football season may be over, but Patrice Bergeron (pictures) and the Boston Bruins are serious contenders for the Stanley Cup. Remember how warm it was for their parade in 2011? Wouldn’t that be nice right about now? Image provided by NHL.com

Monday: A cloudy start, then becoming partly to mostly sunny and breezy. High 33-40 in the morning, then temperatures hold steady or drop a bit in the afternoon.

Monday night: Clear skies in the evening, then clouds start to roll back in after midnight. Low 15-22.

Tuesday: More clouds than sunshine. High 32-39.

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

Wednesday: Cloudy with snow developing, changing to rain at least as far inland as I-95. Becoming windy across Cape Cod and southeastern Massachusetts. High 31-38, except for southeastern Massachusetts, Cape Cod, and southern Rhode Island, where temperatures could jump into the 40s towards evening.

Thursday: Any lingering snow or rain ending early, then gradual clearing is expected. High 28-35.

Friday: A sunny start, then clouds move back in. Some light snow is possible at night. High 25-32.

Saturday: Mostly cloudy, some snow showers possible in the morning. High 35-42.

Sunday: Cloudy with a chance of rain or snow, becoming windy across Cape Cod and southeastern Massachusetts. High 38-45, possibly warmer across southeastern Massachusetts, Cape Cod, and southern Rhode Island.

NBA: Boston Celtics at Philadelphia 76ers

The Bruins aren’t the only team in town primed for a deep post-season run well into the Spring and early Summer. Kyrie Irving and the Celtics are also having a great season. Image provided by NBA.com

Standard