DAYS 1-5 (OCTOBER 18-22)

A cool northwesterly air flow will dominate our weather today and while a trough swings through overhead we’ll have a sun/cloud mix and the chance of a couple pop-up rain showers. The cool air hangs in Tuesday with a breeze, but less clouds as the upper trough pulls away, then heading into midweek high pressure slips to the south of New England and eventually off the Mid Atlantic Coast as we see dry weather and temperature moderating here. A warm front will cross our region early Thursday with some cloudiness and perhaps a few raindrops, but this will be a short-lived event and much of the day ends up fair, mild, and breezy. By later Thursday, low pressure will be moving from the Great Lakes into southeastern Canada and a cold front will be approaching by that evening or night time with a rain shower threat, carrying into Friday as the front moves through the region. By late Friday, we will be experiencing the arrival of another cool air mass from Canada.

TODAY: Sun/cloud mix. Slight chance of a passing rain shower this afternoon. Highs 57-64. Wind NW 10-20 MPH, higher gusts.

TONIGHT: Mostly clear. Patchy frost possible interior lower elevations. Lows 38-45. Wind NW 5-15 MPH but may drop to near calm in valley areas.

TUESDAY: Mostly sunny. Highs 58-65. Wind NW 5-15 MPH.

TUESDAY NIGHT: Clear. Patchy frost possible interior lower elevations. Lows 37-44. Wind W under 10 MPH.

WEDNESDAY: Mostly sunny. Highs 60-67. Wind W up to 10 MPH.

WEDNESDAY NIGHT: Clear evening. Increasing clouds overnight. Patchy ground fog interior low elevations. Lows 41-48. Wind WSW under 10 MPH.

THURSDAY: Mostly cloudy to partly sunny morning with brief light rain possible. Partly to mostly sunny thereafter. Highs 62-69. Wind SW 10-20 MPH.

THURSDAY NIGHT: Variably cloudy. Chance of rain showers. Lows 52-59. Wind SW 10-20 MPH.

FRIDAY: Partly sunny. Chance of rain showers, mainly during the morning. Highs 60-67. Wind SW shifting to NW 10-20 MPH.

DAYS 6-10 (OCTOBER 23-27)

October 23-24 weekend temperatures will likely run below normal here. What’s uncertain is whether it’s a mainly dry weekend (with a few passing pop sprinkles) or if it starts wetter with coastal low pressure passing by Saturday. Leaning toward that low staying far enough offshore for dry weather right now, but need to watch it. High pressure brings dry weather mid period before the next disturbance approaches from the west with milder air but also a rain shower threat by the end of the period.

DAYS 11-15 (OCTOBER 28 – NOVEMBER 1)

Increasing uncertainty for the pattern. We’ve had guidance project a continued west to east flow with up and down temperatures including more chilly air, and we’ve had other guidance project the evolution of a blocking pattern with high pressure to the north, low pressure to the south, and this area on the edge of some stormier weather. A very low confidence outlook leans toward a westerly flow slowly evolving toward a block, some unsettled weather which will be impossible to time this far out, and a tendency for cooler air more than warmer air.

C-19 Chat Post – October 18 2021

DAYS 1-5 (OCTOBER 17-21)

A strong cold front moved offshore during the early morning hours and has delivered an air mass that puts an end to our mild and at times muggy pattern. The feel of the season arrives today and will remain with us for a few days, courtesy a west and northwest flow between low pressure in eastern Canada and high pressure moving from the Great Lakes through the Ohio Valley. An upper level low pressure trough moving across the Northeast. The trough will be responsible for passing clouds both today and Monday, with a few pop up showers possible especially today. The trough will move far enough away for fewer clouds and no shower threat as we head toward midweek, and as high pressure slips off to the south, we’ll experience a temperature moderation especially by Wednesday and Thursday. By later Thursday, low pressure will be moving from the Great Lakes into southeastern Canada and a cold front will be approaching by that evening or night time with a rain shower threat.

TODAY: Sun/cloud mix. Slight chance of a brief passing shower. Highs 60-67. Wind W 10-20 MPH, higher gusts.

TONIGHT: Partly cloudy. Lows 42-49. Wind W 5-15 MPH, higher gusts.

MONDAY: Sun/cloud mix. Highs 57-64. Wind W 10-20 MPH, higher gusts.

MONDAY NIGHT: Mostly clear. Patchy frost possible interior lower elevations. Lows 38-45. Wind NW 5-15 MPH but may drop to near calm in valley areas.

TUESDAY: Mostly sunny. Highs 58-65. Wind NW 5-15 MPH.

TUESDAY NIGHT: Clear. Patchy frost possible interior lower elevations. Lows 37-44. Wind W under 10 MPH.

WEDNESDAY: Mostly sunny. Highs 60-67. Wind W up to 10 MPH.

WEDNESDAY NIGHT: Clear. Patchy ground fog interior low elevations. Lows 41-48. Wind WSW under 10 MPH.

THURSDAY: Mostly sunny to partly cloudy. Chance of rain showers eveing or night. Highs 62-69. Wind SW 10-20 MPH.

DAYS 6-10 (OCTOBER 22-26)

A frontal boundary may still be passing through the region early October 22 with a rain shower threat as low pressure pulls through eastern Canada. High pressure to the west and low pressure to the northeast means a gusty northwesterly air flow and cooler air coming in during October 23-24 and cannot rule a pop up instability shower in otherwise a dry weather pattern. High pressure is expected to bring fair and tranquil weather October 25-26.

DAYS 11-15 (OCTOBER 27-31)

High pressure should be in control early and again late period with an unsettled weather threat mid period. Watching for the potential evolution of a blocking pattern with high pressure to the north and low pressure to the south, but not sure how quickly this takes place, if it takes place…

C-19 Chat Post – October 17 2021

DAYS 1-5 (OCTOBER 16-20)

A warm front has lifted northeastward through the region during the overnight hours and for the day today we are in an air mass that will remind you of the warm and humid days of summertime, although we’ll have an increasing south and southwest wind to contend with. It will remain rain-free through the daylight hours, but a strong cold front approaching from the west will bring a round or two of showers and the chance of a thunderstorm across the region from west to east this evening and overnight. The front will clear the coastline before dawn Sunday and any lingering showers will pull offshore no later than dawn for easternmost areas, if not before that. The air mass behind this front is one more seasonable for this time of year, and after a handful of warm days, you’ll notice a significant change. Sunday will become our second consecutive breezy day, something we have not seen much of this month, which for parts of the region has been the least-windy October in 4 decades. We’ll have to watch for at least some clouds scurrying across the sky Sunday, and a few of them may build enough to produce passing rain showers, but don’t cancel any apple picking plans over that potential. Monday through Wednesday will feature dry weather across the area. High pressure will stretch from the Ohio Valley into the Middle Atlantic and Southeast states while low pressure wraps up and hangs out over the Maritime Provinces of Canada. This puts our region in a cool northwesterly air flow for Monday, which then gradually relaxes as the low loses its grip and the high slides a bit further east, allowing winds to slowly relax and temperatures to slightly moderate as we head toward the middle of this week. I’ve talked about the threat of the first frost for some interior lower elevations Tuesday morning. This threat still exists for both Tuesday and possibly Wednesday mornings depending on what the wind does and how low the dew point gets.

TODAY: Sun/cloud mix. Highs 70-77. Wind S to SW 10-20 MPH, higher gusts.

TONIGHT: Mostly cloudy with showers and a chance of thunderstorms west to east. Lows 53-60. Wind SW 5-15 MPH with higher gusts, shifting to W.

SUNDAY: Sun/cloud mix. Slight chance of a brief passing shower. Highs 60-67. Wind W 10-20 MPH, higher gusts possible.

SUNDAY NIGHT: Partly cloudy. Lows 42-49. Wind W 5-15 MPH, higher gusts.

MONDAY: Sun/cloud mix. Highs 57-64. Wind W 10-20 MPH.

MONDAY NIGHT: Mostly clear. Patchy frost possible interior lower elevations. Lows 38-45. Wind NW 5-15 MPH but may drop to near calm in valley areas.

TUESDAY: Mostly sunny. Highs 58-65. Wind NW 5-15 MPH.

TUESDAY NIGHT: Clear. Patchy frost possible interior lower elevations. Lows 37-44. Wind W under 10 MPH.

WEDNESDAY: Mostly sunny. Highs 60-67. Wind W up to 10 MPH.

DAYS 6-10 (OCTOBER 21-25)

Milder October 21 as low pressure tracks across southeastern Canada bringing a cold front into the region with a shower threat either late October 21 or sometime October 22. Watch for a wave of low pressure which may bring some wet weather to start the October 23-24 weekend followed by a shot of drier and much cooler air. High pressure would bring fair and seasonably cool weather to end the period if things play out as expected.

DAYS 11-15 (OCTOBER 26-30)

High pressure should be in control early and again late period with an unsettled weather threat mid period. Too soon for any details.

C-19 Chat Post – October 16 2021

DAYS 1-5 (OCTOBER 15-19)

High pressure has shifted to the east but we still have a generally dry and very mild October day today, just with more cloudiness than yesterday. A warm front passing by may produce a brief shower especially north and west of Boston tonight, and it will feel a little bit like summer on Saturday with a gusty south to southwest wind, higher humidity, and warm air in place. But it all comes to an end Saturday night when a strong cold front sweeps across the region from west to east, accompanied by showers, a gusty, shifting wind, and a temperature drop. This leads to a Sunday that will feature a sun/cloud mix and perhaps a passing shower due to an upper level trough over the region, and more seasonable air moving in. This will continue into Monday, which will be cooler still. As winds drop off Monday night, under a clear sky we may see some of the first frost of the season in the interior lower elevations, and Tuesday itself looks fair and slightly milder as high pressure moves into the region.

TODAY: Partly sunny. Highs 68-75. Wind variable to SE up to 10 MPH.

TONIGHT: Mostly cloudy. Chance of showers, favoring central MA and southern NH. Patchy fog. Lows 52-59. Wind SE to SW 5-15 MPH.

SATURDAY: Sun/cloud mix. Highs 70-77. Wind SW 10-20 MPH, higher gusts.

SATURDAY NIGHT: Mostly cloudy with showers and a chance of thunderstorms west to east. Lows 53-60. Wind SW 5-15 MPH with higher gusts, shifting to W.

SUNDAY: Sun/cloud mix. Slight chance of a brief passing shower. Highs 60-67. Wind W 10-20 MPH, higher gusts possible.

SUNDAY NIGHT: Partly cloudy. Lows 42-49. Wind W 5-15 MPH, higher gusts.

MONDAY: Sun/cloud mix. Highs 58-65. Wind W 10-20 MPH.

MONDAY NIGHT: Mostly clear. Patchy frost possible interior lower elevations. Lows 38-45. Wind W under 10 MPH.

TUESDAY: Mostly sunny. Highs 60-67. Wind W up to 10 MPH.

DAYS 6-10 (OCTOBER 20-24)

The trend is for more low pressure troughing to show up in eastern Canada and while we have fair and milder weather on October 20 the next unsettled weather system follows toward mid period with shower activity followed by another shot of cool air if things play out as expected.

DAYS 11-15 (OCTOBER 25-29)

Continuing the idea from the days before this, a little more up and down in the temperature pattern but with a tendency for more cool air to win out. Fairly dry pattern overall but still some minor rainfall threats possible.

C-19 Chat Post – October 15 2021

DAYS 1-5 (OCTOBER 14-18)

High pressure dominates today then shifts off to the east Friday and Saturday as low pressure tracks through the Great Lakes and into southeastern Canada, dragging its warm front through the region Friday night / early Saturday followed by a fairly strong cold front Saturday evening and night. While the warm front may produce some showers, the best chance of showers and embedded thunder will be with the cold front mostly after sunset into the late evening and possibly overnight hours Saturday / early Sunday from west to east. Behind this comes a gusty westerly wind, cooler and drier air, but with an upper level trough over the region we can expect to see passing clouds Sunday and Monday and even the possibility of a few showers, mainly Sunday, due to instability.

TODAY: Partly cloudy. Highs 70-77. Wind variable to N up to 10 MPH.

TONIGHT: Variably cloudy. Patchy fog. Lows 53-60. Wind variable under 10 MPH.

FRIDAY: Partly sunny. Highs 68-75. Wind variable to SE up to 10 MPH.

FRIDAY NIGHT: Mostly cloudy. Chance of showers, favoring central MA and southern NH. Patchy fog. Lows 52-59. Wind SE to SW 5-15 MPH.

SATURDAY: Sun/cloud mix. Highs 70-77. Wind SW 10-20 MPH, higher gusts.

SATURDAY NIGHT: Mostly cloudy with showers and a chance of thunderstorms west to east. Lows 53-60. Wind SW 5-15 MPH with higher gusts, shifting to W.

SUNDAY: Sun/cloud mix. Slight chance of a brief passing shower. Highs 61-68. Wind W 10-20 MPH, higher gusts possible.

SUNDAY NIGHT: Partly cloudy. Lows 42-49. Wind W 5-15 MPH, higher gusts.

MONDAY: Sun/cloud mix. Highs 58-65. Wind W 10-20 MPH.

DAYS 6-10 (OCTOBER 19-23)

Broad low pressure troughing may hang in eastern Canada while high pressure tries to move in at the surface, which means fair weather and slight warm-up October 19-20. Next unsettled weather system from the west is due in the October 21-22 window with dry weather returning end of period, based on current timing.

DAYS 11-15 (OCTOBER 24-28)

Differences and inconsistencies in medium range guidance help lead to a lower confidence forecast but for now looking for high pressure to be dominant early to mid period with mostly fair weather and low pressure to threaten later in the period with unsettled weather.

C-19 Chat Post – October 14 2021

DAYS 1-5 (OCTOBER 13-17)

High pressure will be in control with generally fair weather through Friday. A couple of disturbances trying to push into the region will bring clouds at times including a couple of dissipating troughs today and again Thursday, then a warm front passes through the region during Friday evening. Temperatures will continue to run above normal through Saturday, at which time a stronger cold front will be approaching from the west, likely passing through the region during Saturday night / early Sunday, bringing showers and possibly a few thunderstorms as well. This will be followed by a breezy and cooler end to the weekend with a stronger westerly air flow behind the front.

TODAY: Mostly sunny to partly cloudy. Highs 68-75. Wind variable to S up to 10 MPH.

TONIGHT: Partly cloudy. Patchy fog. Lows 52-59. Wind S to variable under 10 MPH.

THURSDAY: Partly cloudy. Highs 69-76. Wind variable up to 10 MPH.

THURSDAY NIGHT: Partly cloudy. Patchy fog. Lows 52-59. Wind variable under 10 MPH.

FRIDAY: Partly cloudy. Highs 70-77. Wind SW up to 10 MPH.

FRIDAY NIGHT: Variably cloudy. A shower possible mainly central MA and southern NH. Patchy fog. Lows 52-59. Wind SW up to 10 MPH.

SATURDAY: Partly sunny. Showers and possible thunderstorms mainly late afternoon / evening. Highs 71-78. Wind SW 5-15 MPH.

SATURDAY NIGHT: Mostly cloudy with showers and a chance of thunderstorms west to east. Lows 53-60. Wind SW 5-15 MPH with higher gusts, shifting to W.

SUNDAY: Sun/cloud mix. Slight chance of a brief passing shower. Highs 61-68. Wind W 10-20 MPH, higher gusts possible.

DAYS 6-10 (OCTOBER 18-22)

High pressure brings fair weather to the region October 18-20, starting out with cooler weather and the chance of the first frost interior low elevations on the morning of October 19, then moderating temperatures follow this. Unsettled weather possible with a low pressure system approaching from the west later in the period.

DAYS 11-15 (OCTOBER 23-27)

High pressure is expected to regain control of the weather with generally dry conditions and near to above normal temperatures for most of this period. May have an approaching system with unsettled weather by the end of the period.

C-19 Chat Post – October 13 2021

DAYS 1-5 (OCTOBER 12-16)

High pressure will be in control with generally fair weather through Friday. Exceptions will be a fairly widespread moderate to dense fog across the region for part of this morning due to moisture trapped at low levels of the atmosphere, and a chance of a spot shower Wednesday from the leftovers of a dissipating trough moving in from the west. Temperatures will run above normal in this pattern not only through Friday, but Saturday as well. That day though is going to bring an increased threat for shower and even possible thunderstorm activity as a strong cold front approaches from the west, but at this point the timing would hold most activity off til evening.

TODAY: Foggy into or through mid morning across most of the region with less fog in parts of the Worcester Hills and across the Cape Cod area. Eventually increasing sun. Highs 65-72. Wind variable to S up to 10 MPH.

TONIGHT: Partly cloudy. Patchy fog. Lows 52-59. Wind S under 10 MPH.

WEDNESDAY: Partly sunny. Slight chance of a shower. Highs 68-75. Wind variable to S up to 10 MPH.

WEDNESDAY NIGHT: Variably cloudy evening. Partly cloudy overnight. Patchy fog. Lows 52-59. Wind S to variable under 10 MPH.

THURSDAY: Partly cloudy. Highs 69-76. Wind variable up to 10 MPH.

THURSDAY NIGHT: Mostly clear. Patchy fog. Lows 52-59. Wind variable under 10 MPH.

FRIDAY: Partly cloudy. Highs 70-77. Wind SW up to 10 MPH.

FRIDAY NIGHT: Variably cloudy. Patchy fog. Lows 52-59. Wind SW up to 10 MPH.

SATURDAY: Partly sunny. Showers and possible thunderstorms mainly late afternoon / evening. Highs 71-78. Wind SW 5-15 MPH.

DAYS 6-10 (OCTOBER 17-21)

A cold front clears the region early October 17 with that day seeing a gusty westerly breeze, drier/cooler air, and just the risk of a brief passing shower. High pressure dominates with fair weather and moderating temperatures October 18-20. Next frontal system and shower threat arrives around the end of the period from the west.

DAYS 11-15 (OCTOBER 22-26)

Westerly air flow with dry and seasonable temperatures expected for early period, then indications are for high pressure to re-build across the region with fair weather and a warming trend following.

C-19 Chat Post – October 12 2021

DAYS 1-5 (OCTOBER 11-15)

The South Coast rain moved offshore overnight, and other than a few pockets of drizzle from leftover low level moisture via the onshore air flow, we’ll be seeing improving weather today. This is the first and probably only time that Columbus Day will also be Marathon Monday due to the pandemic-rescheduled Boston Marathon. The weather for the race will be decent. A patch of drizzle dampened the ground at the Hopkinton start line to the west of Boston, but things will dry out there in the next little while (I write this update just before the race start waves get underway). As both elite early runners and the waves of additional participants and runners make their way along the course they will run into a light head wind, temperatures rising through the 60s, and moderately humid air by October standards (it won’t feel like mid summer humidity). All-in-all, not too bad. The set-up of high pressure to the north and low pressure to the south that has created this weather will be shifting as the high builds over the region through Tuesday, which ends up being a fair and mild day. The mild air continues through mid week and into late week with mostly fair weather, but the remains of a weakening / dissipate trough coming in from the west on Wednesday with bring some cloudiness and the slight chance of a shower.

TODAY: Early drizzle patches end. Mostly cloudy to partly sunny. Highs 64-71. Wind E up to 10 MPH.

TONIGHT: Partly cloudy. Patchy fog. Lows 52-59. Wind SSE up to 10 MPH.

TUESDAY: Partly sunny. Highs 65-72. Wind variable to S up to 10 MPH.

TUESDAY NIGHT: Partly cloudy. Patchy fog. Lows 52-59. Wind S under 10 MPH.

WEDNESDAY: Partly sunny. Slight chance of a shower. Highs 67-74. Wind variable to S up to 10 MPH.

WEDNESDAY NIGHT: Variably cloudy evening. Partly cloudy overnight. Patchy fog. Lows 52-59. Wind S to variable under 10 MPH.

THURSDAY: Partly cloudy. Highs 69-76. Wind variable up to 10 MPH.

THURSDAY NIGHT: Mostly clear. Patchy fog. Lows 52-59. Wind variable under 10 MPH.

FRIDAY: Mostly sunny. Highs 71-78. Wind SW 5-15 MPH.

DAYS 6-10 (OCTOBER 16-20)

Low pressure passes north of New England October 16 with current timing suggesting an early-day warm front passage and a late-day cold front passage. This brings the opportunity for a couple rounds of showers and even a few thunderstorms. This will be followed by gusty wind, dry and cooler weather to round out the weekend on October 17. After this, high pressure moves over the region with dry weather and moderating temperatures into the middle of next week.

DAYS 11-15 (OCTOBER 21-25)

High pressure will try to hang on to start the period but at some point a stronger westerly flow brings a weather system and air mass change. Fine-tuning to be done in the days ahead.