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.

C-19 Chat Post – October 11 2021

DAYS 1-5 (OCTOBER 10-14)

High pressure centered to the northeast of New England and low pressure to the south continue to create a general onshore air flow from the east and northeast. The low to the south will make its best run at us today and this evening, managing to spread some rainfall into the South Coast region and a few patches of rain a little further north into eastern and central MA mainly this afternoon and evening, with some lingering South Coast rain overnight before the high ultimately wins the battle and pushes it all to the south again. This means that Marathon Monday (the first and perhaps only one we’ll ever see in October) will be a rain-free day although there will be a fair amount of cloudiness, moderate humidity and a light head wind for runners. I’m still expecting temperatures to be in the upper 50s to lower 60s for the early part of the racing and well into the 60s later in the day as the mid to back-of-pack runners are finishing. High pressure at the surface and aloft gains stronger control Tuesday and tries to hang on Wednesday while the remains of a weakening / dissipating trough from the west move in, but then the high regains control again by Thursday, so we see generally fair weather and above normal temperatures heading into the middle of the week.

TODAY: Mostly cloudy. Afternoon light rain most likely South Coast with spotty light rain possible elsewhere especially eastern MA. Highs 60-67. Wind E to NE up to 10 MPH, a few gusts around 15-20 MPH South Coast.

TONIGHT: Mostly cloudy. Areas of fog. Chance of light rain favoring RI and southeastern MA mainly evening but lingering near the South Coast overnight. Lows 51-58. Wind ESE up to 10 MPH.

MONDAY: Mostly cloudy to partly sunny. Early-morning patches of light rain possible near Cape Cod. Highs 63-70. Wind SE up to 10 MPH.

MONDAY NIGHT: 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 68-75. Wind variable up to 10 MPH.

DAYS 6-10 (OCTOBER 15-19)

A low pressure area is destined to pass north of New England between late October 15 and late October 16, dragging a warm front / cold front combo across the region. Most rainfall activity with the warm front should stay to the north with October 15 being a partly cloudy and mild day for mid October, and then a round of showers is expected with the cold front, current timing expected to be sometime during the first half of October 16 (Saturday of next weekend) which means the weekend may start out unsettled, after which we should see drier and cooler weather with a westerly breeze take over for the balance of the weekend (through October 17). High pressure looks like it will control the weather with fair weather and another warming trend for the remainder of this period.

DAYS 11-15 (OCTOBER 20-24)

As we head into late October the indications are mixed from our medium range guidance but at this time I lean toward high pressure being in control of the weather here with mostly fair weather and above normal temperatures.. Some guidance has shown a more progressive flow with systems moving through more frequently and at the same time other guidance has shown a slower, more amplified pattern. When I see this conflict, my tendency is to persist with the same forecast from the day before and watch the trends.

C-19 Chat Post – October 10 2021

DAYS 1-5 (OCTOBER 9-13)

High pressure centered over the Canadian Maritimes and low pressure south of New England combine to create onshore flow this 3-day weekend. Low pressure to the south gets close enough to bring a little rainfall mainly to southern areas at some point Sunday and/or Sunday night, otherwise the main swath of moisture from that system stays to the south and other areas see no more than a few patches of drizzle from time to time through Sunday. Watch for high tide splash-over in vulnerable coastal areas today. For the Boston Marathon on Monday, a general head wind is expected along the course with temperatures in the upper 50s to lower 60s near the start of the race and well into the 60s with moderate humidity for later in the race. Periods of sunshine sneak into parts of the region with a bit of a drier air intrusion from time to time, especially today and again during Monday. High and mid level cloud cover will likely be thicker on Sunday preventing much in the way of any sun even if lower clouds break up at times. Tuesday-Wednesday will see a building of high pressure aloft and a shifting of surface high pressure to the east which is a mild weather pattern here. The remnants of a low pressure trough from the west may initiate a few showers in the region Wednesday but otherwise rain-free weather is expected heading toward the middle of next week.

TODAY: Mostly cloudy – partial sun at times. Patches of drizzle possible. Highs 59-66. Wind NE to E 5-15 MPH, diminishing.

TONIGHT: Mostly cloudy. Scattered areas of fog and drizzle. Lows 50-57. Wind E up to 10 MPH.

SUNDAY: Mostly cloudy. A patch of drizzle and fog here and there. Chance of light rain favoring areas south of I-90 mainly during the afternoon. Highs 60-67. Wind E 5-15 MPH.

SUNDAY NIGHT: Mostly cloudy. Areas of fog. Chance of light rain favoring RI and southeastern MA mainly evening. Lows 51-58. Wind ESE up to 10 MPH.

MONDAY: Mostly cloudy to partly sunny. Highs 63-70. Wind SE up to 10 MPH.

MONDAY NIGHT: Mostly to 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.

DAYS 6-10 (OCTOBER 14-18)

High pressure controls with fair weather and above normal temperatures into late next week, then there are signs of a pattern change (said with low to moderate confidence until I see more consistency in medium range guidance). This would bring a cold front through around October 16 and introduce a seasonably cooler westerly air flow with some showers likely marking the change. Timing uncertain of course this far in advance so watch future updates.

DAYS 11-15 (OCTOBER 19-23)

High pressure may re-build over the East Coast with fair weather and above normal temperatures being the most likely weather we see in this stretch. However this is not a high confidence forecast given the uncertainty preceding it, so keep an eye on future updates for this period of time too.

C-19 Chat Post – October 9 2021

DAYS 1-5 (OCTOBER 8-12)

A mild high pressure area will give way to a cooler one from Canada today, and this announcement will be made by a back door cold front that sweeps southwestward across there region this afternoon and early evening, taking a fairly mild day with light wind and introducing a gusty breeze, cooler air, and eventually low clouds from the ocean, which show up before sunset for some coastal areas but wait until tonight to push across most of the region. The moisture coming off the ocean will be enough to produce pockets of drizzle overnight into Saturday morning when the low clouds will be most extensive, then some drier air will work in to help break up those clouds at least in some areas as we go through the day Saturday, so partial sun is possible. I would not cancel any outdoor plans Saturday as the “worst” of the weather would be a period of drizzle in the morning. At least some low cloudiness may return for a time Saturday night into Sunday but at the same time we’ll have mid and high level cloudiness increasing due to low pressure to our south. This is an area of low pressure area that has been talked about for days on this blog and in other media, trying to answer the question as to whether or not it would move up and mess up part of the holiday weekend (specifically Sunday into Monday, which is also the day of the Boston Marathon this year). I think if we get any shower activity it will be Sunday and only indirectly from that low, in combination with a weakening disturbance moving in from the west, and by Monday all of that energy will have been pushed back to the south and high pressure will be strong enough to keep the region rain-free. We still may have a fair amount of cloud cover around Monday and another thing which can be a minor to moderate concern for runners of the Marathon is that the dew point will be a little on the higher side for mid October, with the humid air potentially having some impact. It won’t be oppressive like summertime by any stretch, but just a bit humid. I should also mention that with astronomical high tide, and the ocean stirred up a bit by low pressure that has been sitting to the south for a while, there can be some high tide splash-over in vulnerable locations this weekend, especially Saturday. By Tuesday, the strongest feature affecting our weather will be high pressure offshore, so expect a fair and mild day, but probably not totally sunny as there will still be some moisture left over for clouds.

TODAY: Patchy clouds early morning, sunshine most of the day, but low clouds may arrive in Seacoast NH and far eastern MA by late in the day. Highs 66-73, may quickly turn cooler in southeastern NH and eastern MA during the second half of the afternoon. Wind variable up to 10 MPH through midday, shifting to NE and increasing to 5-15 MPH with higher gusts from northeast to southwest across the region afternoon-evening.

TONIGHT: Becoming cloudy. Patchy drizzle and areas of fog overnight. Lows 48-55. Wind NE 5-15 MPH.

SATURDAY: Cloudy with patchy drizzle and a few areas of fog in the morning. Mostly cloudy to partly sunny in the afternoon. Highs 59-66. Wind NE to E 5-15 MPH, diminishing.

SATURDAY NIGHT: Mostly cloudy. Lows 48-55. Wind E up to 10 MPH.

SUNDAY: Mostly cloudy. Chance of showers. Highs 60-67. Wind E 5-15 MPH.

SUNDAY NIGHT: Mostly cloudy. Areas of fog. Chance of showers. Lows 51-58. Wind ESE up to 10 MPH.

MONDAY: Mostly cloudy to partly sunny. Highs 63-70. Wind SE up to 10 MPH.

MONDAY NIGHT: Mostly to partly cloudy. Patchy fog. Lows 52-59. Wind SSE up to 10 MPH.

TUESDAY: Variably cloudy. Highs 65-72. Wind S up to 10 MPH.

DAYS 6-10 (OCTOBER 13-17)

Other than a couple of very weak / dissipating troughs moving through with some clouds at times, the weather is expected to be governed by high pressure at the surface and aloft much of the time with generally dry weather and above normal temperatures heading through the mid point of October.

DAYS 11-15 (OCTOBER 18-22)

This period should see some giving-way of the high pressure ridging with better opportunities for systems arriving from the west with a couple greater threats for some unsettled weather. Too early for timing on these potentials.

C-19 Chat Post – October 8 2021

DAYS 1-5 (OCTOBER 7-11)

High pressure will remain in control of the weather for most of the next 5 days with one possible interruption about the middle of the holiday weekend. This is going to be dependent on how much interaction there is between an approaching trough from the west and a low pressure area to the south. Right now I am favoring just enough interaction for the chance of some shower activity in the region any time Sunday until very early Monday. Also, after two sunny days today and Friday, a back-door cold front will usher in a maritime air mass and open the door for low cloudiness off the ocean as soon as Friday night lasting into the weekend. So don’t expect the brightest of weekends with all of the above factors taken into account. Monday being the day of the postponed / rescheduled Boston Marathon, it’s of high interest to many in the region, and right now I favor rain-free conditions with abundant cloudiness and moderate humidity for the race. Fine-tuning of this forecast will take place over the next few days.

TODAY: Sunny. Highs 67-74. Wind variable to SW up to 10 MPH.

TONIGHT: Clear except fog patches forming in lower elevations. Lows 46-53, coolest interior valleys. Wind calm.

FRIDAY: Sunny. Highs 66-73 occurring by midday then may turn cooler. Wind variable up to 10 MPH early then N to NE 5-15 MPH with higher gusts.

FRIDAY NIGHT: Partly to mostly cloudy. Lows 45-52. Wind NE 5-15 MPH.

SATURDAY: Mostly cloudy to partly sunny. Highs 59-66. Wind NE 5-15 MPH.

SATURDAY NIGHT: Variably cloudy. Lows 48-55. Wind E up to 10 MPH.

SUNDAY: Mostly cloudy. Chance of showers. Highs 60-67. Wind SE 5-15 MPH.

SUNDAY NIGHT: Mostly cloudy. Areas of fog. Chance of showers. Lows 51-58. Wind SE under 10 MPH.

MONDAY: Mostly cloudy. Chance of a shower early. Highs 61-68. Wind SE to S up to 10 MPH.

DAYS 6-10 (OCTOBER 12-16)

Other than a couple of very weak / dissipating troughs moving through with some clouds at times, the weather is expected to be governed by high pressure at the surface and aloft much of the time with generally dry weather and above normal temperatures heading through the mid point of October.

DAYS 11-15 (OCTOBER 17-21)

This period should see some giving-way of the high pressure ridging with better opportunities for systems arriving from the west with a couple greater threats for some unsettled weather. Too early for timing on these potentials.

C-19 Chat Post – October 7 2021

DAYS 1-5 (OCTOBER 6-10)

High pressure will dominate the weather for the next few days. First, the initial high pressure system in control is on the weak side and its center a little to our northwest, and some lingering low level moisture in the form of fog patches in lower elevations and a layer of scattered to broken clouds a few thousand feet above the ground will take a little time to dissipate, but as the day goes on a drier northwesterly air flow will help this happen. The high center settles over to just south of the region tonight and Thursday and Thursday will be a day that will feature 100% sunshine and rather mild air. A stronger high pressure center will enter the picture from eastern Canada and a frontal boundary between the initial high and this newer high will pass through the region on Friday with no more than a wind shift to northeast and an increase in wind speed. While Friday will be a mild day, it will start to turn cooler as a northeasterly wind strengthens and transports a Canadian air mass into New England. This sets up a cooler weekend with fair weather but probably some amount of cloud cover arriving Saturday both from ocean moisture at lower levels and some higher level moisture from low pressure to our south. This will continue Sunday but add a weak disturbance trying to come through from the west as the high center shifts to the east and we may add even more clouds with perhaps a few showers. The shower threat is not a certainty at this point, but is something to watch.

TODAY: Fog patches and areas of cloudiness morning. Sunnier midday on. Highs 64-71, coolest coast. Wind NW up to 10 MPH but coastal sea breezes.

TONIGHT: Clear except fog patches forming in valleys, swamps, and bogs. Lows 44-49, coolest interior low elevations, except 50-55 in urban centers. Wind variable under 10 MPH.

THURSDAY: Sunny. Highs 67-74. Wind variable to SW up to 10 MPH.

THURSDAY NIGHT: Clear except fog patches re-forming in lower elevations. Lows 46-53, coolest interior valleys. Wind calm.

FRIDAY: Sunny. Highs 66-73 occurring by midday then may turn cooler. Wind variable up to 10 MPH early then N to NE 5-15 MPH with higher gusts.

FRIDAY NIGHT: Partly cloudy. Lows 45-52. Wind NE 5-15 MPH.

SATURDAY: Partly sunny. Highs 59-66. Wind NE 5-15 MPH.

SATURDAY NIGHT: Variably cloudy. Lows 48-55. Wind E up to 10 MPH.

SUNDAY: Mostly cloudy. Chance of a shower. Highs 60-67. Wind SE 5-15 MPH.

DAYS 6-10 (OCTOBER 11-15)

Confidence is moderate to high that high pressure will regain control for dry and mild weather early in the period. We’ll have to watch low pressure to the south again for possible moisture intrusion and wet weather threat by the middle of the period then a return to fair and mild weather later.

DAYS 11-15 (OCTOBER 16-20)

The overall indications are still for high pressure to control with mainly dry weather and above normal temperatures, though toward the end of the period a stronger push from the west may send a front through with a shower chance and introduce some cooler air. Again not a high confidence outlook at this time.

C-19 Chat Post – October 6 2021