DAYS 1-5 (DECEMBER 11-15)

Cold air returns to the region today with active winds, a sun/cloud mix, and perhaps a few snow showers from the combination of cold air advection and limited Great Lakes moisture traveling into our region. Active wind continues tonight into Friday with dry weather and below normal temperatures, but a ridge of high pressure building in will help diminish the wind later Friday and Saturday with continued dry weather. A clipper low will travel just south of our region Sunday, and its interaction with a little energy passing by to our north will determine whether we see just a few snow showers or a more notable period of snow. I’m leaning toward the latter, with the best chance of accumulating snow being from the I-90 belt southward for Sunday – maybe a mix on the Outer Cape / Islands due to marginal temperatures there. Regardless of the solidity of the snow shield, this system exits and leads reinforcing cold into our region for Monday, and the wind will be back again at that time.

TODAY: Sun/cloud mix. Chance of snow showers mainly in the afternoon. Highs 32-39 this morning followed by a slow but steady decline. Wind NW 10-20 MPH, but gusting 25-45 MPH at times.

TONIGHT: Partly cloudy. Chance of a snow flurry in the evening. Lows 17-24. Wind NW 5-15 MPH.

FRIDAY: Partly to mostly sunny. Highs 33-40. Wind NW 5-15 MPH with higher gusts, gradually diminishing.

FRIDAY NIGHT: Partly cloudy. Lows 11-18 except 18-25 coastal and urban areas. Wind W under 10 MPH.

SATURDAY: Partly cloudy. Highs 31-38. Wind W up to 10 MPH.

SATURDAY NIGHT: Mostly cloudy. Lows 17-24. Wind variable under 10 MPH.

SUNDAY: Cloudy. Chance of snow or snow showers. Highs 25-32 except 28-35 South Coast. Wind N up to 10 MPH.

SUNDAY NIGHT: Clearing. Lows 13-20. Wind NW 10-20 MPH, higher gusts.

MONDAY: Mostly sunny. Highs 23-30. Wind NW 10-20 MPH, higher gusts.

DAYS 6-10 (DECEMBER 16-20)

Low pressure tracks into the Great Lakes by the middle of next week with a quick shot of milder air here, then we enter an up-and-down temperature pattern with another small system bringing a chance of precipitation later in the period.

DAYS 11-15 (DECEMBER 21-25)

From the winter solstice to Christmas Day, the pattern can’t be forecast with high confidence, and there is still a lot of uncertainty with guidance inconsistencies, but my current leaning is milder than December has been but not persistently mild – more up and down temps and mostly minor precipitation events with a lot of detail to work out as we get closer to this period of time.

DAYS 1-5 (DECEMBER 10-14)

A mild interlude comes today ahead of a cold front that trails low pressure passing to our north. This front will bring a round of rain showers (maybe some mix higher elevations well north and west of Boston) later today before bringing back a cold air mass overnight that will then be with us into the upcoming weekend. Thursday, upper low pressure and (limited) Great Lakes moisture combine for a snow shower chance, then dry weather is expected with weak high pressure in control Friday through Saturday. Sunday’s weather is to be determined by the track of a clipper low and how much moisture it has to work with, but there is the chance of snow or snow showers from this system with cold air in place in our area. Fine-tuning on the Sunday forecast ahead…

TODAY: Some partial sun morning favoring eastern areas otherwise becoming mostly cloudy. Late-day rain showers from west to east, but may be mixed with snow in higher elevations from north central MA through southwestern NH. Highs 38-45. Wind SW 5-15 MPH.

TONIGHT: Mostly to partly cloudy. Rain showers possible in eastern areas in the evening. Icy areas on untreated surfaces overnight. Lows 28-35. Wind NW 5-15 MPH.

THURSDAY: Sun/cloud mix. Chance of snow showers. Highs 32-39. Wind NW 10-20 MPH, higher gusts.

THURSDAY NIGHT: Partly cloudy. Chance of a snow flurry. Lows 17-24. Wind NW 5-15 MPH.

FRIDAY: Partly to mostly sunny. Highs 33-40. Wind NW 5-15 MPH with higher gusts, gradually diminishing.

FRIDAY NIGHT: Partly cloudy. Lows 11-18 except 18-25 coastal and urban areas. Wind W under 10 MPH.

SATURDAY: Partly cloudy. Highs 31-38. Wind W up to 10 MPH.

SATURDAY NIGHT: Mostly cloudy. Lows 17-24. Wind variable under 10 MPH.

SUNDAY: Cloudy. Chance of snow or snow showers. Highs 25-32. Wind N up to 10 MPH.

DAYS 6-10 (DECEMBER 15-19)

A little more up and down temps possible in this period with low pressure track somewhat variable, potentially one or two systems passing over or north of here, but this is also somewhat uncertain. A lot to work out for detail during this stretch of time.

DAYS 11-15 (DECEMBER 20-24)

Similar ideas going into this period as well but leaning colder over warmer with a couple precipitation opportunities. With it a very low confidence forecast period I won’t venture into anymore detailed explanation than that at this point.

DAYS 1-5 (DECEMBER 9-13)

No notable changes for today’s discussion from yesterday’s. A warm front approaches today and tonight and a short wave disturbance aloft comes through this evening. While there is dry air to overcome at mid levels, this feature is expected to produce a brief period of snow late evening into the overnight hours from west to east, except mix to rain closer to Cape Cod where the temperature will be borderline between supporting frozen and liquid precipitation. If any accumulation of snow occurs with this, it will be minor and mostly away from the coast northwest of Boston. We end up in the “warm” sector for Wednesday, not an overly warm day by December standards, but milder than recent days for sure. A cold front trailing low pressure passing to our north will sweep through with the air mild enough for rain showers in the evening, again progressing west to east but lasting no more than a couple hours in any one location. This front will lead a colder air mass back into our region for Thursday through Saturday. Thursday’s weather will be windiest, with a gradual abatement of the wind on Friday and a more tranquil Saturday as high pressure builds toward the region. Upper level low pressure crossing the region, combined with limited Great Lakes moisture, can result in a few snow showers around the area Thursday. This threat will diminish then vanish for late week as the upper low departs and the wind relaxes.

TODAY: Sun gives way to clouds. Highs 28-35. Wind variable to SE up to 10 MPH.

TONIGHT: Cloudy evening into overnight with a period of light snow/mix except mix/rain South Coast. Snow accumulation of up to but mainly under 1/2 inch can occur mainly inland areas to the north of I-90. Watch for icy spots on untreated surfaces mid to late evening except Cape Cod / Islands. Lows 20-27 except steady 28-35 southeastern MA and southern RI evening, rising slowly overnight. Wind SE under 10 MPH shifting to SW up to 10 MPH.

WEDNESDAY: Partly sunny morning. Mostly cloudy afternoon. Late-day rain showers from west to east, but may be mixed with snow in higher elevations from north central MA through southwestern NH. Highs 38-45. Wind SW 5-15 MPH.

WEDNESDAY NIGHT: Mostly to partly cloudy. Rain showers possible in eastern areas in the evening. Icy areas on untreated surfaces overnight. Lows 28-35. Wind NW 5-15 MPH.

THURSDAY: Sun/cloud mix. Chance of snow showers. Highs 32-39. Wind NW 10-20 MPH, higher gusts.

THURSDAY NIGHT: Partly cloudy. Chance of a snow flurry. Lows 17-24. Wind NW 5-15 MPH.

FRIDAY: Partly to mostly sunny. Chance of a snow flurry early. Highs 34-41. Wind NW 5-15 MPH with higher gusts, gradually diminishing.

FRIDAY NIGHT: Partly cloudy. Lows 11-18 except 18-25 coastal and urban areas. Wind W under 10 MPH.

SATURDAY: Partly cloudy. Highs 31-38. Wind W up to 10 MPH.

DAYS 6-10 (DECEMBER 14-18)

Low pressure brings a chance of snow except snow/mix/rain South Coast during December 14, this being the next in a series of clipper-style low pressure areas. Watching for another system with a precipitation threat around December 17 but less confident on timing. Temperatures mostly below normal for the period.

DAYS 11-15 (DECEMBER 19-23)

Divergence in medium range guidance – nothing new there – doesn’t help forecast confidence atop the normal lower confidence for a period of time this far in the future. For now, the same idea applies. Watching for a brief warm-up from a Great Lakes low then a return to the colder pattern and back on the watch for clipper disturbances as the cold air wins out over a warmer area of air to our south. Caveat: There is enough push from medium range guidance including some ensemble support of a milder scenario toward Christmas – the days just before – so I am not completely discounting a shift to a milder outlook than the one I have now, hence the mention of low confidence.

DAYS 1-5 (DECEMBER 8-12)

This week we will have a parade of small and generally weak to borderline moderate disturbances and low pressure areas moving through our region. The overall pattern is cold, but there will be one brief milder interlude ahead of one of the systems. We had a weak system go by to our north last evening with a few snow flurries in southern NH and far northern MA, as was expected, but nothing to the south. Today’s weather is dry and chilly. The chill continues tomorrow as clouds increase ahead of a warm front, which can produce a period or two of light snow, mainly from the I-90 belt northward, sometime at night. This will lead in the brief shot of milder air for Wednesday ahead of a cold front, trailing the next low passing to our north. This results in a rain shower chance from midday to early evening Wednesday. After the front goes by, colder air returns and untreated surfaces will become icy by early Thursday morning. Thursday’s weather will be blustery and colder with a chance of passing snow showers as upper level low pressure moves overhead. The cold hangs on but the wind will ease up during Friday as low pressure moves away and high pressure builds in with dry weather.

TODAY: Abundant sun. Highs 23-30 except 28-35 South Coast. Wind NW 5-15 MPH, gusts 20-25 MPH.

TONIGHT: Clear. Lows 8-15 except 15-22 South Coast. Wind NW 5-15 MPH shifting to SW and diminishing.

TUESDAY: Sun gives way to clouds. Highs 28-35. Wind variable to SE up to 10 MPH.

TUESDAY NIGHT: Cloudy. A period or two of light snow favoring I-90 northward late evening. Chance of mix to rain showers south of I-90 overnight. Lows 20-27 except steady 28-35 southeastern MA and southern RI evening, rising slowly overnight. Wind SE under 10 MPH shifting to SW up to 10 MPH.

WEDNESDAY: Mostly cloudy. Midday and afternoon rain showers likely, may be mixed with snow in southwestern NH and north central MA higher elevations. Highs 38-45. Wind SW 5-15 MPH.

WEDNESDAY NIGHT: Mostly to partly cloudy. Rain showers possible in eastern areas in the evening. Icy areas on untreated surfaces overnight. Lows 28-35. Wind NW 5-15 MPH.

THURSDAY: Sun/cloud mix. Chance of snow showers. Highs 32-39. Wind NW 10-20 MPH, higher gusts.

THURSDAY NIGHT: Partly cloudy. Chance of a snow flurry. Lows 17-24. Wind NW 5-15 MPH.

FRIDAY: Partly to mostly sunny. Chance of a snow flurry early. Highs 34-41. Wind NW 5-15 MPH, diminishing.

DAYS 6-10 (DECEMBER 13-17)

Overall pattern is cold and features at least a couple disturbances / low pressure areas moving by quickly with precipitation opportunities. Hard to time and detail these chances beyond 5 days out, but will bring them into better focus as they get closer.

DAYS 11-15 (DECEMBER 18-22)

This period remains low confidence in forecasting, but still watching for a Great Lakes low pressure area to allow a short-lived warm-up and a chance of some snow/mix/rain, before cold returns with any disturbances bringing some snow or snow shower chances. Again no real detail or timing is possible this far in advance.

DAYS 1-5 (DECEMBER 7-11)

On yesterday’s blog post I talked about a parade of rather weak low pressure systems ahead, and that outlook remains the same. A fast-moving low will pass to our north tonight with a general light snowfall for northern New England, but here in the WHW forecast area in southeastern New England, we may see just a passing snow shower, favoring areas north of I-90, during this evening and tonight. This will bring a surge of colder air back in for Monday. The next system, a small and weakening low pressure area, will pass north of our region Tuesday evening, again with a passing snow shower chance north of I-90. This will be followed quickly by another clipper-style low moving our way via the Great Lakes, but again with a track that will take it north of our region. This system will have a little more moisture to work with, but also drag in some milder air, with initial snow showers going over to mostly rain showers on Wednesday. Behind this comes another surge of cold air for Thursday with a slight chance of a passing snow flurry, but mainly dry and blustery conditions being the highlight.

TODAY: Partly to mostly cloudy. Highs 34-41. Wind W to SW up to 10 MPH.

TONIGHT: Mostly cloudy. A passing snow shower possible mainly north of I-90 but favoring southern NH. Lows 15-22. Wind W 5-15 MPH shifting to NW.

MONDAY: Mostly sunny. Highs 25-32. Wind NW 10-20 MPH, diminishing.

MONDAY NIGHT: Clear. Lows 8-15. Wind NW under 10 MPH.

TUESDAY: Sun followed by clouds. Highs 28-35. Wind N up to 10 MPH.

TUESDAY NIGHT: Mostly cloudy. A snow shower possible favoring southern NH. Lows 20-27. Wind SW 5-15 MPH.

WEDNESDAY: Mostly cloudy. Scattered to numerous snow/mix to rain showers. Highs 38-45. Wind S 5-15 MPH.

WEDNESDAY NIGHT: Lots of clouds with a lingering rain or snow shower early, then clearing. Lows 17-24. Wind shifting to NW 5-15 MPH, higher gusts.

THURSDAY: Sun and passing clouds with a slight chance of a snow flurry. Highs 32-39. Wind NW 10-20 MPH, higher gusts.

DAYS 6-10 (DECEMBER 12-16)

Watch periods for potential low pressure impact December 12-13 and again later in the period. Temperatures below normal may trend back toward normal later on.

DAYS 11-15 (DECEMBER 17-21)

Not a high-confidence forecast here but best educated guess leads me to lean to one storm traveling into the Great Lakes with a brief warm-up before a return to cold (with a boundary with warmer air not that far to our south). This may increase the opportunity for mix/snow later in the period.

DAYS 1-5 (DECEMBER 6-10)

The pattern during the next 5 days will feature several quick-moving, generally weak low pressure systems to have minor impact overall (in terms of precipitation) but some notable temperature swings with the overall pattern being colder than the long-term average for this point in the season. The first such system is a low pressure area passing well to our south today but its large cloud canopy making it mainly overcast. A northward-extending trough from that low will cause a few snow and rain showers in the region this morning until about midday. The next system will be a clipper-style low passing just to our north Sunday night. This low will have a snow area with it but its track keeps it mainly north of the WHW forecast area, with just a few snow showers occurring mainly to the north of I-90 on Sunday night. Another weakening system flies north of the area Tuesday evening with a remote chance of a snow shower that will favor southern NH with less chance to the south. A slightly more formidable low pressure area, again clipper-style, will head our way via the Great Lakes on Wednesday. The early indications on this are a track to the north, enough to pull milder air into the region making the precipitation, still minor, more likely to be rain showers than snow showers for our region.

TODAY: Mostly cloudy. Scattered snow showers I-90 region northward and mix / rain showers south of I-90 until midday. Highs 35-42. Wind variable up to 10 MPH becoming mainly W.

TONIGHT: Clearing. Lows 18-25. Wind W up to 10 MPH becoming calm.

SUNDAY: Sun followed by clouds. Highs 34-41. Wind SW 5-15 MPH.

SUNDAY NIGHT: Mostly cloudy. Scattered snow showers southern NH and northern MA, isolated snow showers to the south. Lows 13-20. Wind shifting to NW 5-15 MPH with higher gusts.

MONDAY: Mostly sunny. Highs 25-32. Wind NW 10-20 MPH, diminishing.

MONDAY NIGHT: Clear. Lows 8-15. Wind NW under 10 MPH.

TUESDAY: Sun followed by clouds. Highs 28-35. Wind N up to 10 MPH.

TUESDAY NIGHT: Mostly cloudy. A snow shower possible favoring southern NH. Lows 20-27. Wind SW 5-15 MPH.

WEDNESDAY: Mostly cloudy. Increasing chance of mix to rain showers. Highs 38-45. Wind S 5-15 MPH.

DAYS 6-10 (DECEMBER 11-15)

Reinforced cold arrives to start the period along with wind. Watching one or two clipper-style low pressure areas for mix/snow chances mid period before dry, cold weather returns at end of period.

DAYS 11-15 (DECEMBER 16-20)

Guidance trends have been wish-washy the last couple days – basically no help for this period of time. Expectations for indices that tend to control the pattern as well as little use of forecast persistence (old forecast tool I learned as a novice) leads me to not change things too much at this point. I’ll watch for a potential low into the Great Lakes and a brief warm-up, then the region near a battle zone between mild air to the south and cold from Canada, the latter of which probably ends up winning out, and not without a precipitation potential before the end of the period. Lots of time to solve the pattern puzzle here…

DAYS 1-5 (DECEMBER 5-9)

Today we get a glancing shot of the coldest airmass of the late autumn / early meteorological winter so far, with dry weather, and a diminishing wind as high pressure builds in. Tonight and Saturday morning, we watch low pressure pass to our south. A northward extension of a low pressure trough can bring some snow showers to the region Saturday morning and midday – though it may warm just enough for this to mix with or turn to rain showers near the South Coast before ending. Either way, it’s a minor event, then gone. We’ll watch for a small low pressure area to move quickly our way later Sunday, passing just to the north, dragging another strong cold front through the region, with a snow shower chance Sunday late day and night. Reinforcing cold arrives for early next week with dry weather.

TODAY: Mostly sunny. Highs 23-30. Wind NW 5-15 MPH, higher gusts. Wind chill often below 20.

TONIGHT: Clouds increase. Lows 13-20 evening, rising slowly overnight. Wind variable up to 10 MPH.

SATURDAY: Mostly cloudy morning-midday with scattered to numerous snow showers, may turn to rain showers south of I-90 before ending. Highs 35-42. Wind variable up to 10 MPH becoming W.

SATURDAY NIGHT: Mostly clear. Lows 18-25. Wind W up to 10 MPH becoming calm.

SUNDAY: Clouds increase. Snow shower chance late-day. Highs 34-41. Wind SW 5-15 MPH.

SUNDAY NIGHT: Lots of clouds with snow showers likely early, then clearing. Lows 12-19. Wind NW 10-20 MPH.

MONDAY: Mostly sunny. Highs 25-32. Wind NW 10-20 MPH, diminishing.

MONDAY NIGHT: Clear. Lows 8-15. Wind NW under 10 MPH.

TUESDAY: Sun followed by clouds. Highs 28-35. Wind N up to 10 MPH.

DAYS 6-10 (DECEMBER 10-14)

Pattern brings two minor precipitation chances – early December 10, and again later in the period around December 13. Temperatures variable, but mostly below normal.

DAYS 11-15 (DECEMBER 15-19)

One storm may track into the Great Lakes and bring a brief warm-up early in the period before cold air returns for most of the period. One or two clipper systems bring snow or snow shower chances mid to late period.

DAYS 1-5 (DECEMBER 4-8)

A cold and mostly dry pattern is what we have now, but despite the overall dry nature, it’s active, because there are 3 “weather systems” to contend with. The first is an arctic cold front which creates a few snow showers and perhaps a narrow band of heavier snow squalls, favoring areas north of I-90, later today. Watch for that which, if it occurs, can briefly reduce visibility significantly and coat the roads with snow. For folks along the coast, today’s full moon (a super moon) will produce a king tide with areas prone to flooding seeing some of it. Thankfully this is not occurring at the same time as a major coastal storm. The coldest air mass of the season so far will give us a glancing blow tonight and Friday before moving on. Friday night and the first half of Saturday, low pressure will travel to our south, but a little northward extension of the trough from it can produce some snow showers in our area (maybe mix South Coast) – however this will be a minor event. We then watch for another strong cold front to bring a chance of snow showers later Sunday and reinforce the cold air heading into Monday.

TODAY: Partly sunny. A late-day snow shower or snow squall potential, favoring the I-90 belt northward. Highs 37-44. Wind SW 10-20 MPH.

TONIGHT: Partly cloudy early with an evening snow shower potential, followed by clearing. Lows 8-15. Wind NW 5-15 MPH, higher gusts. Wind chill approaches 0.

FRIDAY: Mostly sunny. Highs 23-30. Wind NW 5-15 MPH, higher gusts. Wind chill often below 20.

FRIDAY NIGHT: Mostly cloudy. Chance of snow showers overnight. Lows 15-22 evening, but may rise slightly overnight. Wind variable under 10 MPH.

SATURDAY: Variably cloudy. Chance of snow showers through midday except rain or snow showers South Coast. Highs 35-42. Wind variable up to 10 MPH becoming W.

SATURDAY NIGHT: Mostly clear. Lows 18-25. Wind W up to 10 MPH becoming calm.

SUNDAY: Partly cloudy. Chance of late-day snow showers. Highs 35-42. Wind SW 5-15 MPH.

SUNDAY NIGHT: Clearing. Lows 10-17. Wind NW 10-20 MPH.

MONDAY: Mostly sunny. Highs 25-32. Wind NW 10-20 MPH, diminishing.

DAYS 6-10 (DECEMBER 9-13)

Pattern brings two minor precipitation chances – late December 9 to early December 10, and again later in the period, timing uncertain. Temperatures near to below normal.

DAYS 11-15 (DECEMBER 14-18)

One storm may track into the Great Lakes and bring a brief warm-up, but overall pattern trends colder. Two precipitation changes but no indication of major storms at this point.

DAYS 1-5 (DECEMBER 3-7)

Today’s caution is to watch for icy untreated surfaces in areas where temperatures are near or below freezing at the surface. This will ease up as it climbs above freezing and much drier air and a gusty breeze is present today, resulting in melting / sublimation. Patchy clouds (from departing upper low) and fair weather (from approaching high pressure) will be around today. Thursday’s weather will be mainly fair, but watch for a line or cluster or two of snow showers and potential heavier snow squalls between mid afternoon and early evening – northwest to southeast – associated with an arctic cold front passing through the region. Any heavier snow showers / squalls can rapidly but briefly reduce visibility and produce a quick coating of snow that can lead to hazardous travel. This front ushers in a very cold air mass for Thursday night and Friday, but it doesn’t hang around too long as the core passes quickly. Low pressure passes well south of our region Friday night and Saturday morning with a shot at a little light snowfall, but this looks rather insignificant. A small high pressure builds in with fair weather Saturday afternoon into Sunday, before yet another strong cold front brings a snow shower chance later Sunday.

TODAY: Partly to mostly sunny. Highs 35-42. Wind NW 5-15 MPH, higher gusts.

TONIGHT: Mostly clear. Lows 23-30. Wind SW 5-15 MPH.

THURSDAY: Partly sunny. A late-day snow shower or snow squall potential north and west of Boston. Highs 37-44. Wind SW 10-20 MPH.

THURSDAY NIGHT: Partly cloudy early with an evening snow shower potential Boston area south. Clearing after. Lows 8-15. Wind NW 5-15 MPH, higher gusts. Wind chill approaches 0.

FRIDAY: Mostly sunny. Highs 23-30. Wind NW 5-15 MPH, higher gusts. Wind chill often below 20.

FRIDAY NIGHT: Mostly cloudy. Chance of light snow. Lows 15-22 evening, but may rise slightly overnight. Wind variable under 10 MPH.

SATURDAY: Variably cloudy. Chance of light snow in the morning. Highs 34-41. Wind variable up to 10 MPH becoming W.

SATURDAY NIGHT: Mostly clear. Lows 18-25. Wind W up to 10 MPH becoming calm.

SUNDAY: Partly cloudy. Chance of late-day snow showers. Highs 35-42. Wind SW 5-15 MPH.

DAYS 6-10 (DECEMBER 8-12)

Trend is fairly dry with below normal temps overall. A minor system can bring some precipitation mid period, but looks like a brief and insignificant event.

DAYS 11-15 (DECEMBER 13-17)

One or two precipitation threats in this period with a little more up-and-down temp swings, can include a brief but notable warm-up.

DAYS 1-5 (DECEMBER 2-6)

It’s now the “day-of” the long-talked-about storm threat, which all along has not really looked like that big a deal. Basically there are no changes to what I said yesterday. So basically reiterating, a dual system passing by our region today and tonight consists of a weakening northern system and a strengthening system to the south, the latter of which has a low center that takes over the action as it passes to our south, intensifying, but not at a very rapid rate. Also working with marginal temperatures in place, and the warming influence of the ocean, this system will have a rain/snow line that is mainly north and west of Boston for most of its duration, starting out in the northwest suburbs closer to the city at the onset of precipitation during the mid morning to midday hours, then moving more to the northwest through the time of the low pressure area’s closest pass, before being pulled back to the southeast as the storm begins to move away from the region, with the rain/snow line likely reaching Metro Boston just as the precipitation begins its taper-off process. Additionally, prior to all of this, an initial southerly air flow and a little convergence is creating a band of mix/rain showers in parts of RI and east central MA that will fade by mid morning. This is an indicator of the milder air at the surface which is going to prevent much of any snow from occurring over the South Coast / MA South Shore areas. Snow amounts forecasts haven’t changed and will be reflected again in the detailed forecast section below. Once this storm exits, a quick chill-down will create icy untreated surfaces late tonight into Wednesday morning, so be careful if traveling (by foot or vehicle) during this time. Daytime Wednesday I expect dry, breezy, chilly weather behind the storm system. Still watching for the timing and potential rain and snow showers / squalls with the passage of a sharp cold front later Thursday. Leaning toward a late afternoon snow shower or potential squall in areas north and west of Boston and an evening snow or rain shower with more marginal temps to the south. This front will usher in a very cold air mass for early December, with well-below-normal temperatures, dry weather, and a gusty wind for Friday. A weak low pressure area and trough extending to the north of it will pass by Friday night and Saturday morning with a bit of light snow possible, and a secondary trough may cause a snow flurry later Saturday as well, but that system looks rather benign at this point.

TODAY: Overcast. Precipitation arrives prior to midday north and west of Boston, around midday Boston southward – snow to potential mix I-495 to I-90 north and west, snow/mix to rain I-95 belt, mainly rain but can start as brief mix Boston south. Highs 33-40 except 40-47 Cape Cod / Islands. Wind NE 5-15 MPH.

TONIGHT: Precipitation ending followed by overnight clearing. Expected snow totals generally a trace to 1 inch I-95 belt with closest to 1 inch most likely inland, 1 to 3 inches interior southern NH and I-495 / I-90 region west from I-495 westward, 3 to 6 inches higher elevations Worcester County to interior southern NH, with isolated 6+ amounts at highest elevations. Lows 22-30. Wind shifting to NW 5-15 MPH.

WEDNESDAY: Sunny to partly cloudy. Highs 32-39. Wind NW 10-20 MPH, higher gusts.

WEDNESDAY NIGHT: Mostly clear. Lows 22-29. Wind SW 5-15 MPH.

THURSDAY: Partly sunny. A late-day snow shower or snow squall potential north and west of Boston. Highs 37-44. Wind SW 10-20 MPH.

THURSDAY NIGHT: Partly cloudy early with an evening rain/snow shower potential Boston area south. Clearing after. Lows 8-15. Wind NW 5-15 MPH, higher gusts. Wind chill can approach 0.

FRIDAY: Mostly sunny. Highs 23-30. Wind NW 5-15 MPH. Wind chill often below 20.

FRIDAY NIGHT: Mostly cloudy. Chance of light snow. Lows 15-22 evening, but may rise slightly overnight. Wind variable under 10 MPH.

SATURDAY: Variably cloudy. Chance of light snow early. Chance of a snow shower in the afternoon. Highs 33-40. Wind variable up to 10 MPH.

DAYS 6-10 (DECEMBER 7-11)

Watching for a couple systems to pass through or near the region with mostly minor precipitation threats (snow favored over rain) as temperatures stay mostly below normal during this period.

DAYS 11-15 (DECEMBER 12-16)

Another one or two systems can threaten with rain/mix/snow but early indications are for no major storms. Temperatures trend milder into mid month as the main storm track shifts to the Great Lakes for these systems.

DAYS 1-5 (DECEMBER 1-5)

December 1 marks the start of “Meteorological Winter” which is the months of December through February, but this is a kind of “forcing it to fit into a neat little box” idea, which I kind of like, but mostly don’t like. The fact is this: It’s still autumn. And the upcoming weather pattern discussed here in this section, including the upcoming storm threat, is to be treated as such – a late autumn one, with factors typical of this time of year impacting and shaping the sensible weather we get. It starts today with a chilly, gusty breeze and dry weather behind a cold front that went by our area last evening, as its parent low in eastern Canada creates a tighter pressure gradient between itself and high pressure drifting into the Northeast via the Ohio Valley. Weather systems in this current pattern are quick-movers, however, and we’re already looking at another low pressure trough sending us unsettled weather for Tuesday. As discussed yesterday, this system is actually two systems. The first one is a trough swinging through the Ohio Valley toward the Northeast. The second is a wave of low pressure from the Gulf, moving across the Southeast, with a low pressure area taking shape off the North Carolina Coast. These 2 systems will not fully merge until beyond our region, and the result is a minor to moderate impact system with ocean-warmed boundary layer air preventing significant snow in the coastal plain while the better chance of enough snow to need shovels and plows occurs inland, especially west and northwest of Boston, favoring higher elevations. It’s also a short-duration precipitation event of about 12 hours (+/- a couple hours), from mid morning to mid evening. The high pressure area that approaches us today will move right on through and not be anchored to the north as you’d see in a pattern that featured more blocking. As the southern low passes by, pretty far offshore, it will be intensifying, and right at the end of the storm it will help to draw in some colder air which can drag a rain/snow line closer to the coast, but this will be toward the end of the system and not allow much time for accumulating snow there once it is cold enough to adhere to surfaces. The colder air coming in behind the storm will be a concern for causing icy surfaces that are untreated. In areas that saw mostly rain, this will be the main concern in terms of slippery surfaces. Wednesday’s weather will be dry as high pressure builds in, and this will help sublimate / dry off those surfaces. Thursday, look for a strong cold front to cross the region later in the day from northwest to southeast with a good chance of some rain and snow shower / squall activity. I still need to pin down timing and intensity / precipitation-type for the activity associated with the front in the next few updates. This front will usher in the coldest air mass we’ve seen so far this season for the end of the week.

TODAY: Sun/cloud mix. Highs 38-45. Wind W 10-20 MPH, higher gusts.

TONIGHT: Clouding up. Lows 22-29. Wind N up to 10 MPH.

TUESDAY: Overcast. Precipitation arrives prior to midday north and west of Boston, around midday Boston southward – snow to potential mix I-495 to I-90 north and west, snow/mix to rain I-95 belt, mainly rain but can start as brief mix Boston south. Highs 33-40 except 40-47 Cape Cod / Islands. Wind NE 5-15 MPH.

TUESDAY NIGHT: Precipitation ending followed by overnight clearing. Expected snow totals generally a trace to 1 inch I-95 belt with closest to 1 inch most likely inland, 1 to 3 inches interior southern NH and I-495 / I-90 region west from I-495 westward, 3 to 6 inches higher elevations Worcester County to interior southern NH, with a slight chance of isolated 6+ amounts at highest elevations. Lows 22-30. Wind shifting to NW 5-15 MPH.

WEDNESDAY: Sunny to partly cloudy. Highs 32-39. Wind NW 15-25 MPH.

WEDNESDAY NIGHT: Mostly clear. Lows 22-29. Wind SW 5-15 MPH.

THURSDAY: Variably cloudy. Chance of rain and snow showers. Highs 37-44. Wind SW 10-20 MPH shifting to NW.

THURSDAY NIGHT: Clearing. Lows 8-15. Wind NW 5-15 MPH, higher gusts. Wind chill can approach 0.

FRIDAY: Mostly sunny. Highs 23-30. Wind NW 5-15 MPH. Wind chill often below 20.

DAYS 6-10 (DECEMBER 6-10)

Minor storm system comes through with a precipitation threat early December 6, then watching another potential rain/mix/snow threat later December 7 from what also looks like a fairly minor storm system. Generally fair thereafter. Temperatures recover to near normal on the weekend then fall below normal early next week.

DAYS 11-15 (DECEMBER 11-15)

Colder pattern may transition to a little milder heading toward mid month as upper air pattern shifts somewhat. A couple of precipitation threat windows exist in this time frame but no early indications of major storms.

DAYS 1-5 (NOVEMBER 30 – DECEMBER 4)

Last day of November! Here comes another weather system in a month that’s seen quite a few pass by, but a lack of larger storm events. This is no different. A low pressure system moves quickly through the Great Lakes and into southeastern Canada. Its warm front is going by our region this morning with a blanket of mid level clouds, but some snowfall being generated by the front is passing north and west of our area (WHW) as was expected to happen. It’s the cold front trailing the low that will bring us a round or two of rain showers from later this afternoon into this evening as it sweeps across the region from west to east. And then we welcome December with a chilly, blustery day on Monday, but with dry conditions. This sets the stage for our next “weather system” – a much talked about system coming our way from the southwest on Tuesday. As usual, guidance has been all over the place in its array of simulations repeatedly run on the family of models we have access to, for better or for worse, adding a lot of noise to the information stream, but what really counts is what this system is going to actually do to our region. This is my best educated guess: This storm threat is born of 2 “pieces of energy”. The first one is a trough swinging through the Ohio Valley toward the Northeast. The second is a wave of low pressure from the Gulf, moving across the Southeast, with a low pressure area taking shape off the North Carolina Coast. These 2 systems would have to fully merge before a stronger storm could result, and that won’t be happening until they are east of our longitude. What we get is a system that is the result of the process of the merger. Most of our moisture is actually going to come from the northern system, with minor infusion from the southern one. The track of the low associated with the southern system is going to be pretty far off our coast as it goes by, and while it will be strengthening, it’s not doing so at such a rate that helps draw in colder air. We also will lack a cold high to the north, which in the progressive nature of the pattern will be sliding away through Atlantic Canada as what remains of the northern system progresses east northeastward. Despite the track pretty far south, we will be in the circulation of the newer storm, which as you know at this time of year is going to pull ocean-warmed air into the coastal plain. Also, this will be a fairly short-duration event – from about mid morning to mid evening Tuesday – approximately 12 hours. Putting all this together, we’re looking at greatest chances for accumulating snow that you have to perform snow removal for outside of the I-95 belt – favoring higher elevations of southern NH and central MA, while chances for that kind of snowfall drop off rapidly the further east and south you go, in favor of a rain event – which could start as mix/snow and end as mix/snow for some depending on the precipitation and temperature profile as the system comes through. There will be colder air coming in right behind the system, so icing up of untreated surfaces will be a concern by the early hours of Wednesday. Wednesday’s weather will be dry, chilly, and breezy behind the system. A cold front is expected to cross the region on Thursday from northwest to southeast, bringing the chance of rain and snow showers. I’ll look a little more closely at that for timing and rain showers vs. snow showers in the next update.

TODAY: Mostly cloudy. Rain showers likely west to east by late-day. Highs 45-52. Wind S 5-15 MPH.

TONIGHT: Mostly cloudy with rain showers likely in the evening. Partly cloudy overnight. Lows 30-37. Wind shifting to W 10-20 MPH, higher gusts.

MONDAY: Sun/cloud mix. Highs 38-45. Wind W 10-20 MPH, higher gusts.

MONDAY NIGHT: Clouding up. Lows 22-29. Wind N up to 10 MPH.

TUESDAY: Overcast. Precipitation arrives prior to midday north and west of Boston, around midday Boston southward – snow to potential mix I-495 to I-90 north and west, snow/mix to rain I-95 belt, mainly rain but can start as brief mix Boston south. Highs 33-40 except 40-47 Cape Cod / Islands. Wind NE 5-15 MPH.

TUESDAY NIGHT: Precipitation ending followed by overnight clearing. Expected snow totals generally a trace to 1 inch I-95 belt with closest to 1 inch most likely inland, 1 to 3 inches interior southern NH and I-495 / I-90 region west from I-495 westward, 3 to 6 inches higher elevations Worcester County to interior southern NH, with a slight chance of isolated 6+ amounts at highest elevations. Lows 22-30. Wind shifting to NW 5-15 MPH.

WEDNESDAY: Sunny to partly cloudy. Highs 32-39. Wind NW 15-25 MPH.

WEDNESDAY NIGHT: Mostly clear. Lows 22-29. Wind SW 5-15 MPH.

THURSDAY: Variably cloudy. Chance of rain and snow showers. Highs 37-44. Wind SW 10-20 MPH shifting to NW.

DAYS 6-10 (DECEMBER 5-9)

With a somewhat active jet stream pattern (doesn’t mean all hits here) it is somewhat difficult to time unsettled weather threats, but eyeing late December 5 to early December 6, and December 7 as potential unsettled time frames. No solid indications of major storminess and too early to determine any precipitation types / transitions. Overall temperature pattern favors near to slightly below normal.

DAYS 11-15 (DECEMBER 10-14)

Colder pattern may transition to a little milder heading toward mid month as upper air pattern shifts somewhat. A couple of precipitation threat windows exist in this time frame with fine-tuning to come.

DAYS 1-5 (NOVEMBER 29 – DECEMBER 3)

High pressure builds in today with dry, cold conditions, but diminishing wind. The high slides off to the northeast by Sunday as low pressure tracks through the Great Lakes. Its warm front passes by in the morning but produces some snow/mix north and west of the WHW forecast area. We have abundant cloud cover and at best very limited sun (very early morning some areas and maybe a break or two midday into afternoon). The cold front trailing the low produces rain showers from west to east from mid afternoon to mid evening before exiting offshore. Behind this system, December arrives with a chilly, dry, breezy day on Monday. A pattern of quick-moving systems means the next low pressure area rockets northeastward from the US Southeast on Tuesday and brings a swath of precipitation into our region by Tuesday afternoon into Tuesday night. The dilemma with this upcoming threat with not much help from wishy-washy guidance is to figure out the exact track and rate of deepening of low pressure which both play a role in determining precipitation type and intensity. Our antecedent air mass will be chilly, but not really a deeply cold one with no solid high pressure area to the north to hold that cold air in place. Being very early December, the ocean water temperature is still relatively warm (compared to where it will be by mid winter). As far as low pressure goes, I am continuing to lean toward a flatter, faster system, a little bit further south than some of the guidance shows, along with slower deepening. While this is a slightly colder scenario, it doesn’t lock in a significant snowfall especially for areas near and east of I-95, because of the antecedent marginal temps and the ocean’s influence. So the current leaning is for a relatively short-duration event, with light to borderline snowfall potential inland and mix to rain at the coast and to the south of Boston. There are still 3 regular blog updates to come to refine and finalize this forecast. Regardless of the storm details, it’s gone by Wednesday, which will be a dry, blustery, and colder day.

TODAY: Mostly sunny. Highs 36-43. Wind W 5-15 MPH, diminishing late.

TONIGHT: Clear evening. Increasing high clouds overnight. Lows 18-25. Wind calm.

SUNDAY: Mostly cloudy. Rain showers likely west to east by late-day. Highs 45-52. Wind S 5-15 MPH.

SUNDAY NIGHT: Mostly cloudy with rain showers likely in the evening. Partly cloudy overnight. Lows 30-37. Wind shifting to W 10-20 MPH, higher gusts.

MONDAY: Sun/cloud mix. Highs 38-45. Wind W 10-20 MPH, higher gusts.

MONDAY NIGHT: Clouding up. Lows 22-29. Wind N up to 10 MPH.

TUESDAY: Overcast. Snow/mix/rain probable. Highs 35-42. Wind NE 5-15 MPH.

TUESDAY NIGHT: Cloudy early with precipitation ending. Clearing overnight. Lows 22-30. Wind shifting to NW 5-15 MPH.

WEDNESDAY: Sunny to partly cloudy. Highs 32-39. Wind NW 15-25 MPH.

DAYS 6-10 (DECEMBER 4-8)

Overall pattern is set to feature near to below normal temperatures. Watching for a frontal passage December 4 and potential low pressure impact some time over the December 6-7 weekend, but leaning toward that being a miss to the south.

DAYS 11-15 (DECEMBER 9-13)

Colder pattern continues. Difficult to time potential precipitation threats, but a mid period frontal passage and a late period low pressure impact potential are being watched.

DAYS 1-5 (NOVEMBER 28 – DECEMBER 2)

Look out! Black Friday is here. If you’re doing the classic shopping run-around or attempting outside lights and decorations for the holiday season, you’ll be met with chilly air and a very gusty breeze as the air flows between high pressure to our west and low pressure over southeastern Canada. We’ll have to watch for some snow showers that may migrate our way from the Great Lakes with the help of a pool of cold air passing overhead making it a bit more unstable today. At worst, a couple of these snow showers could briefly dust surfaces that are cold enough, although some measurable amounts are possible in highest elevations, otherwise I don’t expect any major issues from any that occur. High pressure moving closer to the region will keep the cold in place but as the pressure gradient relaxes with the eastern Canadian storm moving further away, Saturday will see less wind and plenty of sunshine. The next low pressure system heads for southeastern Canada via the Great Lakes on Sunday. A warm front extending from this low will pass by our region in the morning, but any snow/mix it produces should remain west and north of our region – maybe a brief period of very light snow north central MA to southern NH. The cold front trailing the low will sweep through our region Sunday evening, and ahead of it will come some rain showers late Sunday afternoon into Sunday evening. The system exits later at night, and Monday will be a chilly, breezy, dry day as a new Canadian air mass arrives. Another quick-moving low pressure area will take shape and move northeastward to threaten our region with precipitation by Tuesday afternoon and night. The track of the low pressure area will determine its impact on our area. The majority of guidance indicates a storm system close enough to bring a variety of precipitation to the region, favoring rain at the coast and snow inland / higher elevation areas, although there is also some guidance that has been very consistent on bringing a flatter, less developed low pressure wave south of our area with a glancing blow of a little light snowfall. With this being a “day 5” forecast as of this update, I’m going to leave the door open to either of these outcomes being possible, and fine-tune as we go.

TODAY: Intervals of sun between many clouds. A passing snow shower possible, especially afternoon. Highs 38-45. Wind W 15-25 MPH, gusts 30+ MPH.

TONIGHT: Partly cloudy. Chance of a snow flurry early. Lows 23-30. Wind W 10-20 MPH, higher gusts.

SATURDAY: Mostly sunny. Highs 36-43. Wind W 5-15 MPH, diminishing late.

SATURDAY NIGHT: Clear evening. Increasing high clouds overnight. Lows 18-25. Wind calm.

SUNDAY: Mostly cloudy. Rain showers likely west to east by late-day. Highs 45-52. Wind S 5-15 MPH.

SUNDAY NIGHT: Mostly cloudy with rain showers likely in the evening. Partly cloudy overnight. Lows 30-37. Wind shifting to W 10-20 MPH, higher gusts.

MONDAY: Sun/cloud mix. Highs 38-45. Wind W 10-20 MPH, higher gusts.

MONDAY NIGHT: Clouding up. Lows 22-29. Wind N up to 10 MPH.

TUESDAY: Overcast. Snow/mix/rain probable. Highs 32-39. Wind NE 5-15 MPH.

DAYS 6-10 (DECEMBER 3-7)

Overall pattern is set to feature near to below normal temperatures. Watching for a frontal passage December 4 and potential low pressure impact some time over the December 6-7 weekend.

DAYS 11-15 (DECEMBER 8-12)

Colder pattern continues. Difficult to time potential precipitation threats, but leaning toward the end of this time frame.

DAYS 1-5 (NOVEMBER 27 – DECEMBER 1)

Happy Thanksgiving to all! The holiday today will feature blustery, chilly, but dry weather behind a cold front that went by the region late last night. Other than wind gusts playing havoc with some kicks and passes in some of the many high school football match-ups, and forcing spectators to dress for it, it’ll be quite a nice holiday for moving about outside. The gusty wind is doing its part, however, to transport the coldest air mass of the autumn so far into our region, and we’ll feel that for sure Friday and Saturday. Winds will be most notable on Friday while we have a strong pressure gradient between high pressure over the Great Lakes and a large storm in eastern Canada, and that day can also have a few passing snow showers as Great Lakes moisture combines with a cold pool of air aloft associated with an upper trough. Saturday, though colder than normal for the date, will become more tolerable due the wind dropping off as high pressure builds into our region and relaxes the pressure gradient. We’ll lose the snow flurry threat that day as the cold pool aloft departs and the air flow doesn’t allow the Great Lakes moisture to make it all the way to our region. This high pressure area will crest over the region Saturday night, then move off to the east as low pressure heads for the Great Lakes, eventually to travel down the St. Lawrence Valley during Sunday and Sunday night. A warm front passes by here early Sunday, followed by a cold front Sunday night. The warm front will generate snowfall that will occur north of our area – over northern New England. The cold front will generate rain showers that will pass through our region late Sunday afternoon into Sunday evening. This system is moving quickly enough so that it will have cleared the coastline in time for a breezy, chilly and dry start to December on Monday – similar to today’s weather.

TODAY (THANKSGIVING): Mostly sunny start, then a sun/cloud mix. Highs 45-52 this morning, then lowering through the 40s this afternoon. Wind W increasing to 10-20 MPH with gusts 25+ MPH.

TONIGHT: Partly cloudy. Lows 25-32. Wind W 10-20 MPH, higher gusts.

FRIDAY: Intervals of sun between many clouds. A passing snow shower possible, especially afternoon. Highs 38-45. Wind W 15-25 MPH, gusts 30+ MPH.

FRIDAY NIGHT: Partly cloudy. Chance of a snow flurry early. Lows 23-30. Wind W 10-20 MPH, higher gusts.

SATURDAY: Mostly sunny. Highs 36-43. Wind W 5-15 MPH, diminishing late.

SATURDAY NIGHT: Clear evening. Increasing high clouds overnight. Lows 18-25. Wind calm.

SUNDAY: Mostly cloudy. Rain showers likely west to east by late-day. Highs 45-52. Wind S 5-15 MPH.

SUNDAY NIGHT: Mostly cloudy with rain showers likely in the evening. Partly cloudy overnight. Lows 30-37. Wind shifting to W 10-20 MPH, higher gusts.

MONDAY: Sun/cloud mix. Highs 38-45. Wind W 10-20 MPH, higher gusts.

DAYS 6-10 (DECEMBER 2-6)

Colder weather pattern. Watching a wave of low pressure with a snow/rain/mix threat later December 2 to early December 3. Leaning toward a flatter, faster system that can’t develop quickly in the upper set-up, therefore a glancing blow or even a miss, but this is not a high confidence outlook this far in advance. Another system from threatens some precipitation by the end of the period – doesn’t look significant.

DAYS 11-15 (DECEMBER 7-11)

Colder pattern continues. Watching systems with potential precipitation early period and late period. Neither of these presents as a major storm by all current indications, but either or both could bring the threat of some frozen precipitation.