4:40PM

It’s Christmas Week. Maybe 2 weekends included in it, with the holiday itself being on Wednesday. There is a lot to cover, but most importantly are the events ongoing now through Monday, because some areas of southern New Hampshire and even valley areas of north central and northeastern Massachusetts will see some icing issues. The low level cold air that has been advertised arrived from the north pretty much on schedule, from New Hampshire into Massachusetts, with a boundary between this as a very warm air mass to the south setting up somewhere south and southwest of Boston Sunday afternoon. Precipitation has been confined mostly to northern New England, where it is much colder, with moderate to major icing, causing some damage and power outages. Here in southeastern New England, there are areas of fog and drizzle and a few areas of rain, but the bigger story has been the contrast of temperatures from the 30s in northeastern MA right into Boston, to the 60s in much of interior southeastern MA and RI. This boundary will not move too much through early Monday, other than to sink a bit further to the south. On Monday, a stronger cold front from the west will sweep through the region, though with slow to moderate pace, so rain and valley icing will still be a likely occurrence before everything ends from west to east, possibly as some snow showers when colder air comes back in aloft.

Once we get to Tuesday (Christmas Eve), the cold air will be established again, and a trough of low pressure moving through the region from west to east will likely bring cloudiness and the threat of some snow shower activity. A cold and dry Christmas Day is expected Wednesday, as the timing of the next system that I thought may arrive that day will be pushed back until around Thursday, with some snow showers again possible then. Another dry and bright day is expected Friday as high pressure moves in. A warm front may produce some cloudiness but not likely any meaningful precipitation for Saturday, before an Arctic cold front brings yet another chance of snow showers and a blast of colder air about next Sunday.

Forecast for southeastern New England…

TONIGHT: Overcast. Areas of dense fog. Periods of rain, especially north of the Mass Pike, with icing likely interior valleys of east central and northeastern MA and southern NH. Lows around 30 interior valleys to middle 30s most areas except 40-50 far southern areas. Wind light N-NE most areas, calm at times, except SW 5-15 MPH near the South Coast.

MONDAY: Cloudy. Areas of fog. Periods of rain except freezing rain interior valleys of MA and NH in the morning. Highs 35-40 most areas except falling through the 40s in southern areas. Wind variable 5-15 MPH becoming mostly N to NW.

MONDAY NIGHT: Mostly cloudy. Chance of rain or snow showers Cape Cod and South Coast, snow showers elsewhere. Lows 25-35, coldest northwest of Boston. Wind NW 10-20 MPH.

TUESDAY: Variably cloudy. Chance of snow showers. Highs 30-35. Wind NW 10-20 MPH.

TUESDAY NIGHT – CHRISTMAS EVE: Partly cloudy. Chance of snow showers. Lows 10-15 except 15-20 South Coast. Wind N 5-15 MPH.

WEDNESDAY – CHRISTMAS DAY: Mostly sunny. Highs in the 20s. Wind N 10-20 MPH.

THURSDAY: Variably cloudy. Chance of snow showers. Lows 10-18. Highs 25-33.

FRIDAY: Mostly sunny. Lows 10-18. Highs 25-33.

SATURDAY: Mostly cloudy. Lows 20-28. Highs 33-40.

SUNDAY: Variably cloudy. Chance of snow showers. Temperatures falling 30s to 20s.

3:16AM

This weekend it’s all about the line between a warm air mass just south of New England, whose northern edge will poke into southern New England with potential record high temperatures, and a very cold air mass in northern New England and southeastern Canada, whose edge will try to push southward and undercut the mild air. For us in southeastern New England, it only makes for a tough temperature forecast, as the bulk of the precipitation that does occur will fall as rain (not ice) and the heaviest and steadiest of which will stay north of the region. How I think it will play out, with the cold air sinking into southern NH and northeastern MA Saturday night and Sunday, will be reflected in the wording in the forecast below. The biggest plague of the weekend may be areas of dense fog that form, especially over areas that have a significant snow cover (mainly Boston area northward). As we get to the start of the new week, a cold front will push all of this offshore, but the transition on Monday may be rather slow, so it will be a day of occasional wet weather and lowering temperatures. By Tuesday (Christmas Eve), a fresh cold air mass will have moved in, and a weak disturbance moving into the region may touch off a few snow showers. Wednesday (Christmas Day) will also be cold, and we’ll have to watch the timing of a weak clipper system, for the potential for a touch of light snow. A slight moderation in temperature should occur later next week, but only back to normal, along with a few more disturbances bringing clouds and a few risks of snow showers.

Updated forecast for southeastern New England…

TODAY: Mostly cloudy. Highs 45-50. Wind SW up to 10 MPH.

TONIGHT: Mostly cloudy. Spotty light rain mainly northern MA and southern NH. Areas of fog. Lows 40-45 but may fall into the 30s southern NH and northeastern MA. Wind SW up to 10 MPH may shift to N in southern NH and northeastern MA.

SUNDAY: Southern NH and northern MA – overcast with areas of fog and drizzle, and a chance of a few periods of light rain, temperatures in the 40s, and light N to NE wind. Southern MA and RI – mostly cloudy, a few rain showers possible, highs in the 50s, and WSW wind up to 10 MPH.

MONDAY: Cloudy. Chance of light rain. Areas of fog. Temperatures fall through 40s.

TUESDAY – CHRISTMAS EVE: Partly cloudy. Isolated snow showers. Lows around 20. Highs around 30.

WEDNESDAY – CHRISTMAS DAY: Variably cloudy. Chance of light snow. Lows in the 10s. Highs around 30.

THURSDAY & FRIDAY: Variably cloudy. Episodes of snow showers. Lows in the 20s. Highs in the 30s.

10:13PM

The coldest of the recent spell has gone by, and it will turn a little milder the remainder of this week. But low level cold air will be lingering just to the north as high pressure will be tending to develop there. With snow cover in much of the region (except closer to the South Coast), this will act like a refrigerator, temporing warm-ups, and making it easy for cold air to drain in from the north. Before all of this happens, a warm front will try to push out the last of the current cold air as it passes by early Friday, but a cold front will approach later Friday into Saturday and sink across the region during the weekend. The position of that front will determine temperatures which may vary widely across parts of the region. There will also be some periods of wet weather, mostly in the form of rain, though not a whole lot of precipitation will likely occur. We’ll also have to watch for the potential for icing over the interior areas depending on how much cold is able to drain into the region later in the weekend.

A peek into next week: Cold front sinks to the southeast of the region Monday with mild air replaced by cold. Cold high pressure builds in Tuesday with maybe a few Christmas Eve snow showers, and (timing uncertain) watching a potential clipper system for a bit of Christmas Day snow.

Updated forecast for southeastern New England (southern NH, eastern MA, and RI)…

OVERNIGHT: Clear. Watch for icy patches on ground. Lows from near 10 inland valleys to near 20 South Coast. Wind W under 10 MPH.

THURSDAY: Increasing clouds. Highs 30 inland hills to middle 30s South Coast. Wind W 5-15 MPH gusting over 20 MPH.

THURSDAY NIGHT: Mostly cloudy. Lows around 30. Wind variable 5-15 MPH.

FRIDAY: Mostly cloudy. Highs around 40. Wind SW 5-15 MPH.

SATURDAY: Cloudy. Chance of rain showers early. Lows in the middle 30s. Highs in the lower 40s.

SUNDAY: Cloudy. Periods of light rain (ice possible inland valleys). Lows around 30. Highs around 40 north to 50 south daytime, may rise at night.

MONDAY: Mostly cloudy. Chance of rain showers early. Temperatures fall through 40s.

TUESDAY – CHRISTMAS EVE: Partly cloudy. Isolated snow showers. Lows around 20. Highs around 30.

WEDNESDAY – CHRISTMAS DAY: Mostly cloudy. Chance of light snow. Lows around 20. Highs around 30.

7:46AM

A clipper storm will move across the region today. A classic one. The phrase classic clipper does not mean a big storm (in this case, snow). It means that a system moving along the northern jet stream, out of Canada, will pass just south of most of New England, probably cutting across Cape Cod or the Islands as it redevelops, then accelerates out to sea while intensifying. This is a perfect track to bring light to moderate snow in this cold set-up. We’ll see that this afternoon and evening, except limited accumulations over Cape Cod and the South Coast due to mixing.

The clipper is gone by tomorrow morning, and we’re left with fair weather, a breezy/cold Wednesday as sun returns and then a chilly but more tranquil Thursday as sun gives way to clouds from an approaching warm front. This leads to a milder end of the week, and also unsettled, Friday-Sunday, as a front moves into then lingers in the area. It’s hard to time any precipitation this far out, but if anything takes place, odds favor rain and rather light amounts. Fine tuning of this will take place as it gets closer.

Forecast for southeastern New England…

TODAY: Clouding over west to east this morning with snow develop west to east early through mid afternoon and continuing. Highs barely to 20 remote NW suburbs of Boston, pushing beyond 30 over Cape Cod. Wind light N to NE except E to SE over Cape Cod and the Islands.

TONIGHT: Cloudy with snow in the evening, except mix/rain parts of the South Coast and Cape Cod. Accumulations less than 3 inches where mix or rain occurs, 3-7 inches elsewhere with isolated 8 inch amounts possible especially northeastern MA and southern NH. Temperatures steady. Wind variable over Cape Cod, NE to N 5-15 MPH elsewhere.

WEDNESDAY: Clearing. Highs around 30. Wind NW 10-20 MPH and gusty.

THURSDAY: Increasing clouds. Low 15. High 33.

FRIDAY: Mostly cloudy. Chance of rain showers. Low 33. High 45.

SATURDAY-SUNDAY: Mostly cloudy. A few periods of precipitation, probably rain, favoring Sunday. Lows 25-35. Highs 35-45.

MONDAY: Variably cloudy. Chance of snow showers. Low 20. High 33.

3:50PM

The coming week will feature cold & wind, a little more snow, a little more cold, a brief warm-up, then a transition back to seasonable cold with a possible snow threat on the weekend (don’t read too much into this yet – it’s way off).

Behind our messy weekend storm, high pressure moving in and low pressure moving away will funnel gusty winds and cold air across the region Monday, feeling more like the middle of January. Sunshine will be plenty, but ineffective.

A clipper-type low pressure area will move fairly quickly out of the Midwest and into Northeast Tuesday, redeveloping off the coast before scooting away toward the Canadian Maritime Provinces. The rate of deepening of this new low will determine how much snow falls. It will be snow, as temperatures will not be an issue. The current thinking is a light to moderate snowfall (3-6 inches on average) Tuesday afternoon and night.

Low pressure moves away Wednesday and other than some lingering snow showers with a surge of cold air coming in, it will be a sun/clouds and gusty winds kind of day.

A warm front approaches on Thursday, which will be a chilly day with increasing cloudiness. Not expecting any precipitation from the warm front at this time.

A brief warm-up on Friday behind the warm front and ahead of a cold front, which will probably produce some rain showers, and give us a chance to clean up any lingering snow and ice in places we don’t want it to be, though not nearly enough to melt the snowcover anywhere it was above about 3 inches from the weekend storm.

The cold front that passes Friday will slow down just offshore on Saturday and allow a low pressure wave to ride up along it. The track of that low and how deep we get back into seasonably cold air will determine if precipitation reaches the region and what form it will be in. It’s too early to really be sure. At this very early stage I’ll lean toward a rain/mix the further southeast you are, and snow the further northwest you are, but that’s just more basic meteorology than thorough scientific analysis at this stage.

Forecast for southeastern New England (southern NH, eastern MA, and RI)…

TONIGHT: Clearing. Lows drop below 10 in snowcovered valleys to the 10s elsewhere. Wind W 5-15 MPH.

MONDAY: Mostly sunny. Highs in the 20s. Wind WNW 15-25 MPH gusting to 40 MPH. Wind chill as low as 10.

MONDAY NIGHT: Clear evening. Increasing high clouds overnight. Lows 10-15. Diminishing wind.

TUESDAY: Thickening overcast. Snow afternoon and evening. Early accumulation estimate 2-6 inches of light and fluffy snow. Highs in the 20s. Wind variable 5-15 MPH.

WEDNESDAY: Chance of snow showers early otherwise increasing sun. Low 15. High 30.

THURSDAY: Increasing clouds. Low 18. High 33.

FRIDAY: Partly sunny. Late-day rain showers. Low 28. High 46.

WEEKEND: Mostly cloudy. Snow/mix possible Saturday night and Sunday. Lows in the 20s. Highs in the 30s.

9:55AM

Short summary now and updated forecast now .. full discussion later today on The Week Ahead post.

Storm is all but done. It was tough to nail it down but finally feel that it worked out mostly as expected with a few surprises, as they always seem to have. If you have snow to move please try to do it during the day today as anything leftover in areas that saw wetter snow or rain at the end of the storm will freeze solid tonight.

Upcoming… A dry, windy, and cold Monday as modified arctic air overtakes the region. Disturbance from the west redevelops as a new storm just offshore Tuesday afternoon and night, producing measurable snow (early call on this would be something in the 2-4 inch range but with the likely dry/fluffy nature of this system there could be a few higher amounts). Dry weather returns Wednesday as the small storm departs. A late week warm-up is still expected. A warm front passes Thursday night and leads the warmer air in, which hangs around for about a day until a cold front moves through by the start of next weekend.

Updated forecast for southeastern New England…

TODAY: Cloudy with spotty drizzle this morning. Partial clearing this afternoon. Temperatures starting out in the 20s in remote NW suburbs and interior southern NH ranging all the way to near 50 Cape Cod, staying steady to the NW but falling elsewhere. Wind NW 10-20 MPH and gusty.

TONIGHT: Partly cloudy. Lows 10-15 except 15-20 South Coast. Wind WNW 10-20 MPH.

MONDAY: Mostly sunny. Highs in the 20s. Wind W 15-25 MPH and gusty.

TUESDAY: Clouding over with snow afternoon and night with up to a few inches likely. Lows 10-18. Highs in the 20s.

WEDNESDAY: Clearing. Low 12. High 30.

THURSDAY: Increasing clouds. Lows 13. High 32.

FRIDAY: Partly sunny. Rain showers late. Low 32. High 48.

SATURDAY: Mostly cloudy. Snow showers early. Low 30. High 39.

3:37AM

First, apologies for lack of entry during Friday. On top of very busy schedule which never really allowed me to update, nasty cold keeping me slow. Battling, and winning, but it’ll take a few days. Ah the joys. Actually I can’t complain. The last few years I seem to fight them off very well while everyone around me gets nailed by them. Once in a while one sneaks in. Such is life.

Weekend Storm: It comes down to this. The cold high versus the low with milder air. My original thinking of a weaker, colder scenario looked great on paper, but the problem is this – the high to the north, though associated with dense, cold air, is not that strong, and is giving way somewhat. This allows the primary low to hold a bit longer, and the secondary low to try to form a little closer to the primary as it looks for a weakness in the high to the north. Does that mean that the models trend of a coastal hugger and a milder solution will verify completely? Not necessarily. The cold air will be tough to dislodge. I do believe a snowier solution continues longer than models have on current runs (as of the writing of this blog). But I still believe that model precipitation is over-forecast, and the fast-moving nature of the system will also limit what totals may have been. That said, other than the South Coast and immediate shoreline of eastern MA, the vast majority of the measurable precipitation over southeastern New England is still likely to fall as snow, with a moderate accumulation (up slightly from the light-to-moderate call yesterday). The bulk of this will occur between midnight and dawn (tonight/Sunday). As Sunday goes by, it may be mild enough for a mix/rain in many areas as precipitation tapers off, but it is unlikely that any heavy rain will occur. Accumulations of snow with this system will likely range from an inch or 2 over Cape Cod and the South Coast to 2-4 inches over the remainder of southeastern MA and interior southern RI and possibly the immediate shoreline of eastern MA, 4-8 inches most other areas with some isolated greater-than-8 amounts over interior eastern MA and southern NH. A few double-digit totals are possible, but I don’t expect these to be the rule. **IMPORTANT NOTE** .. With a boundary located not far from the coast, there will likely be a very sharp gradient in snowfall amounts and snow consistency from wetter near the shore to fluffy and dry not that far inland. Coastal flooding may occur on east-facing shores at the times of high tide, but this is not a super-powerful storm so flooding will be on the minor side and mainly in the most prone areas.

Next week: Quieter pattern returns, chilly early to mid week with a possible episode of insignificant snow around Tuesday with a low pressure trough, and a milder end to the week (though that warm-up looks relatively brief with a return to cold not far behind).

Forecast for southeastern New England…

TODAY: Fading sun as high to middle clouds thicken. Some lower clouds drift in from ocean in the afternoon and may bring isolated snow showers to east coastal locations. Highs in the 20s. Wind light NE to E.

TONIGHT: Overcast. Snow develops but is mainly on the light side through midnight, then grows heavier overnight when most of the accumulation takes place, but a mix/change to sleet/rain takes place South Coast then working slowly northward toward dawn, and immediate eastern shores of MA later, cutting down accumulations some (for numbers, see discussion above). Temperatures steady in the 20s inland, rising to the lower to middle 30s South Coast. Wind E to SE 10-20 MPH with higher gusts immediate eastern shores and South Coast, NE to N 5-15 MPH but gusting over 20 MPH inland.

SUNDAY: Overcast morning with precipitation ending southwest to northeast as light mix/rain most areas, some snow holding interior MA and NH, but little additional accumulation. Mostly cloudy afternoon with spotty drizzle or very light snow. Highs in the 30s. Wind NE (except variable in far southeastern areas) shifting to NW 10-20 MPH with higher gusts.

MONDAY: Mostly sunny. Low 10. High 25.

TUESDAY: Mostly cloudy. Chance of snow showers. Low 15. High 30.

WEDNESDAY: Partly sunny. Low 15. High 30.

THURSDAY: Partly cloudy. Low 15. High 30.

FRIDAY: Partly sunny. Low 20. High 40.

7:25AM

It’s cold, no doubt. But also frozen in place is the forecast from the previous entry. A short summary: One arctic cold front is by, and a second one will settle into the region on Friday and hang out in the region for a day or so before washing out. These will keep it nice and cold. A storm system is expected to make a run at the region over the weekend and as discussed previously will never really develop into a major system, being whipped along the jet stream rather rapidly. This is the colder solution that has been expected to take place. Computer guidance will still spit out too much precipitation, and based on that, a first forecast of 3-6 inches of general snowfall will hold in this update as well, with not too much mix/rain involved, save for the South Coast and Cape Cod. After the storm’s passage, it’s back to more cold, with a threat of a little more snow about Tuesday of next week. There are still hints of one or two milder days later next week which will probably be followed by even more cold weather.

Updated forecast for southeastern New England…

TODAY: Mostly sunny. Highs in the 20s. Wind NW 5-15 MPH.

TONIGHT: Mostly clear. Lows 10-18. Wind N 5-15 MPH.

FRIDAY: Mostly sunny to partly cloudy. Highs in the 20s. Wind W 10-20 MPH.

FRIDAY NIGHT: Partly cloudy. Lows around 10. Wind light N.

SATURDAY: Increasing cloudiness. Chance of snow late. Highs in the 20s. Wind N to NE 5-15 MPH.

SATURDAY NIGHT: Cloudy with snow likely – several inches of accumulation probable, with some mix/rain possible South Coast and Cape Cod. Temperatures holding in the 20s. Wind NE 5-15 MPH.

SUNDAY: Mostly cloudy. Snow tapering to snow showers. Highs in the 20s. Wind N to NW 10-20 MPH.

MONDAY: Partly cloudy. Lows 10-18. Highs in the 20s.

TUESDAY: Mostly cloudy. Chance of snow. Lows 12-20. Highs around 30.

WEDNESDAY: Partly cloudy. Lows 10-18. Highs in the 20s.

7:17AM

It’s a cold and dry pattern for the next few days. The only threat of precipitation will be isolated snow showers this evening with the passage of an arctic cold front, otherwise a westerly flow turns more northerly Thursday and Friday as the cold air becomes established. This sets the stage for a potential snow threat this weekend, depending on the track of expected low pressure moving south of New England as high pressure stretches across areas to the north and northeast of the region. It’s still too early to get into any details about weekend storm potential, but my feeling is that model forecast has been erring with a system too strong and too close, so I’ll be initially calling for a weaker, faster-moving, system with a colder solution, which results in a lighter snowfall versus a big storm.

Updated forecast for southeastern New England…

TODAY: Mostly sunny. Highs 30-35. Wind W 15-25 MPH.

TONIGHT: Partly cloudy. Isolated snow showers. Lows 15-20. Wind NW 15-25 MPH.

THURSDAY: Mostly sunny. Highs 20-25. Wind N 10-20 MPH.

FRIDAY: Mostly sunny. Low 14. High 24.

SATURDAY: Increasing clouds. Snow at night. Low 10. High 27.

SUNDAY: Mostly cloudy. Morning snow, afternoon flurries. Low 19. High 27.

MONDAY: Partly cloudy. Low 17. High 27.

TUESDAY: Partly cloudy. Low 16. High 30.

7:28AM

A wave of low pressure riding up a cold front just offshore will toss an area of snow into southeastern New England today, mainly from late morning through mid afternoon. The snow will be most significant along the South Coast with less to the north, with snow probably never really making it to southern NH. Amounts below will reflect this set-up.

Then a dry and very cold stretch of weather will take hold Wednesday through Friday as we finally get a taste of some of the arctic air that has been dominant to the west and north of the region.

The weekend looks unsettled but I’m low confidence on the details of how that will play out, so that will be revisited soon.

Forecast for southeastern New England…

TODAY: Cloudy with a period of snow developing from southwest to northeast this morning and ending late in the day with accumulations less than 1 inch in most areas north of the Mass Pike (isolated 1 inch+ amounts possible) and 1-3 inches from around the Mass Pike southward (isolated greater than 3 inch amounts possible). Temperatures steady in the 30s. Wind NW to W 5-15 MPH.

TONIGHT: Clearing. Lows 15-20. Wind W 5-15 MPH.

WEDNESDAY: Mostly sunny. Highs around 30. Wind W 10-20 MPH and gusty.

THURSDAY AND FRIDAY: Dry. Lows 10-18. Highs in the 20s.

SATURDAY AND SUNDAY: Unsettled with episodes of snow/mix possible. Lows in the 20s. Highs in the 30s.

MONDAY: Dry. Lows in the 10s. Highs in the 20s.

2:39AM

We remain near the boundary between very cold air to the north and west and milder air to the south and east, and that means some unsettled weather today with snow/ice/rain. This system is expected to behave as described in the last blog entry, with a light amount of snow to start the day today, except mix/rain closer to the South Coast and Cape Cod, with the rain area advancing northward to include all of the region by early afternoon. Cold air at the surface means some icing will take place over interior MA and NH for several hours during the morning and midday, with some hazardous travel on untreated surfaces. This system winds down later today and is gone tonight, with lingering clouds and some fog around. As expected, its trailing cold front will linger just offshore and allow a wave of low pressure to move up along it Tuesday, bringing a good chance of a period of mix/snow to RI, eastern MA, and coastal NH, though this should be moving along rather quickly and snow amounts will be limited. Drier and cold weather will dominate from the middle of the week to the start of the weekend, with a few minor disturbances bringing occasional clouds and a slight chance of snow showers. A trough moving into the region at some point over the weekend may increase the chance of some snow, though early indications are that this would not be a big storm.

Forecast for southeastern New England (southern NH, eastern MA, RI)…

TODAY: Overcast. Areas of snow, except mix/rain southeastern MA and southern RI, changing to rain south to north, with a period of icing interior MA/NH through midday. Morning snow accumulation from a coating to 2 inches, highest amounts from the higher elevations well NW of Boston into interior southern NH. Highs middle 30s to around 40. Wind E 5-15 MPH.

TONIGHT: Mostly cloudy. Areas of fog. Lows 30-35. Wind light NE.

TUESDAY: Mostly cloudy. A period of snow, some mix coast, mainly coastal NH, eastern MA, and RI, with some minor snow accumulation. Highs 35-40. Wind NE 5-15 MPH.

WEDNESDAY: Partly cloudy. Low 15. High 28.

THURSDAY: Partly cloudy. Low 14. High 26.

FRIDAY: Partly cloudy. Isolated snow showers. Low 11. High 24.

SATURDAY: AM sun. PM clouds. Chance of snow at night. Low 10. High 28.

SUNDAY: Mostly cloudy. Snow showers possible. Low 15. High 30.

2:30AM

A bright and cold start and a grey and cold finish can be expected today as high pressure to the north of the region slips away to the east and a low pressure area approaches the Great Lakes and spreads increasing cloudiness across southern New England. This system will attempt to redevelop just south of New England and track just offshore, but will be quite weak and rather fast-moving. With cold air locked at the surface for the early to middle stages of the event Monday morning, most areas will start as snow, but as warm air comes in aloft rather rapidly, a change to rain will take place. This rain will freeze on the surfaces it falls on in areas north and west of Boston for a time Monday morning to midday, with the best chance of some minor icing being mainly near I-495 through the Worcester Hills and into interior southern NH. But even here the ice should melt as temperatures go above freezing during Monday afternoon. Moisture exits the region from south to north by Monday evening but we may be left with some fog. As low pressure finally pulls away by early Tuesday, we’ll see drying and cooling take place, but a frontal system trailing the low will be lingering offshore and a wave of low pressure will ride up along it and bring the chance of a period of light mix/snow to the South Coast and Cape Cod Tuesday morning to early afternoon. The mid to late week will feature dry and cold weather as a northwesterly flow becomes established. A few disturbances moving along the flow may bring some clouds at times and there may also be a few instances where snow showers from the Great Lakes try to sneak into parts of the region, but these will be the exception rather than the rule, and the main story will be the cold along with some windy episodes.

Updated forecast for southeastern New England…

TODAY: Sunshine fading behind increasing cloudiness. Highs in the 30s. Wind light variable.

TONIGHT: Overcast. Light snow developing overnight, except mix/rain South Coast. Lows in the 20s except 30-35 South Coast. Wind light SE.

MONDAY: Overcast. Snow from Boston area north and west, mix/rain to the south early, changing to rain all areas during the morning but a period of freezing rain interior MA and NH. Rain tapering off late. Areas of fog. Highs upper 30s to middle 40s, coolest interior valley areas. Wind SE 5-15 MPH.

TUESDAY: Mostly cloudy. A period of light snow/mix South Coast through Cape Cod through early afternoon. Temperatures in the 30s.

WEDNESDAY-FRIDAY: Partly cloudy periods. Isolated snow showers. Lows 10s to lower 20s. Highs middle 20s to lower 30s.

SATURDAY: Sun to clouds. Lows 10-20. Highs 25-35.

6:42PM

A chilly and mostly dry weekend will be book-ended by the departure of one minor storm and the arrival of another minor to moderate system, both of which will include some snow, and one of which will include some icing.

The first system has been in the area and has been a strung-out area of moisture occurring with mild air, but now that a cold front has passed, colder air is filtering in, and the last plume of moisture sliding northeastward through the region tonight into early Saturday will start as rain and then change to snow as the cold air finally becomes established enough at all levels. But since this is a fast-moving system and it’s coming at the end of a very mild period, the ground is relatively warm, and amounts will be kept down.

Behind this system, brighter and cold weather will dominate for Saturday afternoon through early Sunday, and though it will remain cold through late Sunday as well, we’ll lose the sunshine as cloudiness advances from the next system. This system later Sunday night and Monday will start as snow in most if not all areas (mix/rain South Coast), but warmer air advancing quickly northward first in the upper levels will switch precipitation over to rain during the early morning hours of Monday. However, cold air will be harder to dislodge at the surface over inland areas (especially from around Interstate 495 northwestward and especially north central MA into interior southern NH. These areas will see a period of icing during the morning Monday, which will make travel somewhat hazardous. By later Monday, these areas will have warmed above freezing and the ice will disappear. That system will exit Monday night and Tuesday through midweek will feature a return to dry weather and colder than normal conditions, along with some gusty wind.

Forecast for southeastern New England (southern NH, eastern MA, and RI)…

TONIGHT: Overcast.  Rain develops early from southwest to northeast, but a changeover to snow takes place from northwest to southeast from around 9PM through midnight, then precipitation gradually tapers off during the overnight hours. Snow accumulations will be around a coating to 1 inch away from the coast in eastern MA and southern NH, but 1-3 inches may occur on unpaved surfaces especially in higher elevations of western and northern Middlesex County of MA northwestward from there. Lows around 30. Wind N under 10 MPH.

SATURDAY: Mostly cloudy with spotty light snow possible in the morning. Increasing sun midday through afternoon. Highs in the 30s. Wind NW up to 10 MPH.

SATURDAY NIGHT: Clear. Lows 15-25, coldest inland valleys. Wind light variable.

SUNDAY: Sunshine followed by increasing cloudiness. Highs in the 30s. Wind variable up to 10 MPH.

MONDAY: Early morning hours snow except mix South Coast, changing to rain south to north morning but a period of ice inland eastern MA and southern NH, then rain, tapering off late. Lows in the 20s. Highs upper 30s to lower 40s.

TUESDAY: Partly sunny. Lows around 30. Highs in the 30s.

WEDNESDAY THROUGH FRIDAY: Dry and cold. Lows 10-20. Highs 22-32.

7:21AM

We here in southeastern New England will find ourselves near the border of mild and cold during the next several days, and this means we’re setting up for several periods of unsettled weather. Without delving into the hype-fueled frenzy of dramatic what-if’s and gloom-and-doom scenarios, the remainder of this section of the blog entry will detail the players (weather systems) and the expected plays (resultant weather) during the next several days.

High pressure dominates with a nice day today, but it may start with patchy fog and frosty windows in some locations after a mostly clear and calm overnight allowed radiational cooling and moisture in the air to condense. The daylight hours will feature sunshine which will quickly erase any of the early fog/frost as it turns rather mild. Clouds will begin to increase later in the day ahead of a warm front, which will slog its way into southern New England by early Thursday. This front may have trouble pushing all the way through the region Thursday (watch for this in the temperature forecast), but will produce some light rain activity. A cold front will come along by Friday and send a couple batches of rain or showers into and across the region. Timing is a little uncertain, but it looks like the bulk of the rain will come in 2 batches, one in the early morning hours of Friday, the second on Friday night. As the cold front settles through the region it will hang up near or just off the coast, but allow enough cold air in so that we will see a mix with or change to snow sometime in the Friday night to early Saturday time frame as the final batch of precipitation moves through. The amount of time that snow can occur will be greater to the north and west of Boston and less to the south. The timing will also determine if any accumulation occurs. An early call is for a minor accumulation away from the coast and especially in higher elevations northwest of Boston. Either way, clouds may hang on through Saturday, because the upper level air flow will likely be from the southwest, and with the front barely offshore, that is often a setup for clouds streaming northeastward in the vicinity of the front. Eventually enough of a push of colder air from the northwest will clear things out, especially for the second half of the weekend, so expect a nice but chilly Sunday. This will be short-lived, as the next weather system will be coming along for early next week. With the colder air in place, we’ll have to watch for some potential for some snow/ice to be involved in at least part of the early-next-week storm, but it is far too early to really have any idea of details. The early feeling is that the main storm will be cutting through the Great Lakes, so even though we may have cold air around to start, we’ll likely warm up at some point during the system’s passage. But with the cold air lurking close by, it all needs to be watched. For now, generic wording will be used on the outlook for the start of next week.

Updated forecast for southeastern New England (southern NH, eastern MA, and RI)…

TODAY: Areas of fog and frost early morning (watch for a few icy patches), then sunshine, but fading late in the day behind advancing clouds. Highs 42-50, coolest in higher elevations northwest of Boston and mildest over interior southern NH and eastern MA. Wind W up to 10 MPH.

TONIGHT: Partly to mostly cloudy. Lows around 30. Wind light variable.

THURSDAY: Mostly cloudy. A chance of light rain, mainly morning and midday. Highs around 40 in southern NH to the lower 50s southern MA and RI. Wind light SE in areas to the north, light S to SW in areas to the south.

FRIDAY: Cloudy. Periods of rain, especially in the early morning (pre-dawn) and late day. Low 40. High 50.

SATURDAY: Mostly cloudy. Chance of mix/snow early morning. Low 30. High 40.

SUNDAY: Mostly sunny. Low 20. High 35.

MONDAY: Cloudy. Ice to rain, may start as snow. Low 30. High 40.

TUESDAY: Cloudy. Chance of rain/mix/snow. Low 32. High 40.

5:25PM

Apologies for the lack of “The Week Ahead”. This post takes the place of it for this week. 🙂

It will be a milder week than the previous, with no major weather systems, just sluggish cold front late in the week. An ocean storm will remain far enough offshore to keep its precipitation shield over the water Tuesday and early Wednesday, but it will stir up the waters and that in combination with astronomical high tides may result in minor coastal flooding, especially at the Tuesday morning high tide. The general pattern across the US this week features a trough in the Southwest and a long southwest to northeast jet stream into the eastern US with a ridge of high pressure east of Florida. Very cold air exists in Canada and though it cannot make a full punch into the East at this time, pieces of it will glance the region at times.

Forecast for southeastern New England (southern NH, eastern MA, and RI)…

TONIGHT: Lots of clouds. Patchy fog. Lows 30-35. Wind N under 10 MPH.

TUESDAY: Lots of clouds and patchy fog in the morning. Increasing sun in the afternoon. Highs in the 40s. Wind N to NW up to 10 MPH.

TUESDAY NIGHT: Clear. Lows in the upper 20s valleys to middle 30s coast and urban areas. Wind light NW.

WEDNESDAY: Sunshine followed by increasing cloudiness. Highs around 40. Wind NW up to 10 MPH becoming light variable.

THURSDAY: AM rain showers / PM partial sun. Low 35. High 45.

FRIDAY: Cloudy. Rain showers possible. Low 35. High 47.

SATURDAY: Mostly cloudy. Low 28. High 41.

SUNDAY: Partly cloudy. Low 23. High 38.

MONDAY: Cloudy. Chance of rain. Low 34. High 44.