Friday July 23 2021 Forecast (8:57AM)

DAYS 1-5 (JULY 23-27)

So yesterday the atmosphere decided to make showers that were not really forecast (except by a couple short range models if one was paying close enough attention). I did not put them in my forecast, thinking fair-weather clouds were sufficient to predict, not expecting them to grow enough to produce showers. But they did, albeit isolated. Still, if you were under one of these, they did produce a few downpours, and a bonus rainbow or two (I saw a brief double. In fact, I saw a rain bow and in the opposite part of the sky a sun dog, seeing both at the same time for the first time, which was cool!). So I’ll take the minor forecast miss and yet another lesson learned for that nice little bonus at the end of my day. Today, we have these showers in the forecast, as a disturbance will be crossing the region this afternoon and early evening, but once again they should be fairly isolated in coverage, but should you be visited by one, a down pour could occur for a brief time. Primary window for activity today, which may include some thunder too, is about 2:00 p.m. to about sunset (mid afternoon through early evening). After that we’ll see clearing and a refreshing air mass reinforced, setting us up for a beautiful day on Saturday with lots of sun with mild and dry air. Now, our pattern is improved over recent abundant overcast and rainfall, but we’re still somewhat unsettled, and that will be evident Sunday as the next disturbance moves into the mean trough position in our region, a warm front bringing lots of clouds and occasional wet weather, especially in the afternoon and evening based on current timing. These systems can move more quickly than prognosticated by even shorter-range guidance so it would not surprise me if showers are already nearby in the morning. Based on this, the forecast wording will reflect a shower threat all day, but but at this time it seems likely that the greatest chance and highest coverage will occur as we get deeper into the day, if you want to take the chance on planning something outside. A warm front will push through later Sunday, and a cold front will follow this, probably passing by during Monday morning. Monday will be a day we’ll likely see our shower chances start out higher, then drop off with fair and slightly less humid air following a Sunday night humidity spike. Tuesday should be a mostly dry and seasonably warm day, but a weak disturbance moving by may be enough to trigger a few showers and thunderstorms during the afternoon hours, but being several days away, the certainty is not there, and I’ll take a closer look at that as we go along.

TODAY: Sun/cloud mix. Isolated to scattered showers and possible thunderstorms mostly mid afternoon on. Highs 76-83. Dew point upper 50s to lower 60s. Wind W 5-15 MPH.

TONIGHT: Mostly clear. Patchy ground fog lower elevation areas. Lows 55-62. Dew point middle 50s. Wind NW up to 10 MPH.

SATURDAY: Mostly sunny. Highs 76-83. Dew point upper 50s. Wind W 5-15 MPH.

SATURDAY NIGHT: Increasing clouds. Lower elevation fog patches. Lows 57-64. Dew point upper 50s. Wind W under 10 MPH.

SUNDAY: Mostly cloudy. Shower chances increasing throughout the day. Highs 76-83. Dew point rising into 60s. Wind W 5-15 MPH shifting to S.

SUNDAY NIGHT: Mostly cloudy. Showers likely evening. Chance of showers and possibly a thunderstorm overnight. Patchy fog. Lows 65-72. Dew point upper 60s to lower 70s. Wind SW up to 10 MPH.

MONDAY: Partly sunny. Chance of showers and possibly a thunderstorm, favoring the morning-midday hours. Highs 78-85. Dew point lower 60s. Wind W 5-15 MPH shifting to NW.

MONDAY NIGHT: Clear. Lows 60-67. Dew point upper 50s. Wind NW up to 10 MPH.

TUESDAY: Partly cloudy. Isolated afternoon showers or thunderstorms possible. Highs 78-85. Dew point near 60. Wind W 5-15 MPH.

DAYS 6-10 (JULY 28 – AUGUST 1)

Overall pattern is drier, but not without shower/thunderstorm chances, which seem highest from later July 28 into July 29 at this time, based on best timing of strongest disturbances coming along a mostly west to northwest flow. Temperatures for the period averaging close to normal.

DAYS 11-15 (AUGUST 2-6)

Overall pattern of west to northwesterly air flow, with no major heat, temperatures near normal, and a drier overall regime with limited shower chances.

Thursday July 22 2021 Forecast (7:31AM)

DAYS 1-5 (JULY 22-26)

Wet pattern: Gone. Frequently high humidity: Gone (for now). Wildfire smoke: Mostly gone. The pattern change we’ve talked about is well-underway, and essentially complete. This new pattern won’t last forever either, but it will be with us long enough to dry out nicely in the days ahead, despite the fact that we still have to deal with a couple disturbances and shower chances. But first, high pressure from Canada brings us our nicest day in quite some time today. You’ll notice the sky a deeper shade of blue as the smoke plume that was passing through has moved off to the southeast, and the next area of smoke stays well to the west, at least through Friday before we may have to deal with some of it once again at some point over the weekend. A disturbance will pass through the region Friday and combined with daytime heating will likely generate diurnal showers, which look like they will be only isolated in coverage, but could produce brief localized downpours in some locations, but this is still an improvement over what we’ve had. This will be followed by another Canadian high pressure area and more great weather Saturday. Our west northwesterly air flow will bring the next disturbance toward the region for Sunday into Monday, a warm front / cold front combo. The warm front will move across the region Sunday with a lot of clouds and a round or two of showers, though that day will be far from a “rainy day” as there will be dry times too. The cold front moves through sometime during the first half of Monday based on current timing, and may bring a few showers and thunderstorms, but again this looks like a much lower coverage event than many we had seen before. Higher humidity will accompany the unsettled weather Sunday-Monday, but not looking for oppressive conditions.

TODAY: Sunny start, then a sun/cloud mix. Highs 76-83. Dew point ranging from middle 50s to lower 60s north to south may lower a little more during the day. Wind NW 5-15 MPH.

TONIGHT: Partly cloudy. Fog patches forming interior lower elevations. Lows 56-63. Dew point lower to middle 50s. Wind NW under 10 MPH shifting to W.

FRIDAY: Partly sunny. Isolated showers and a slight chance of a thunderstorm in the afternoon. Highs 74-81. Dew point middle to upper 50s. Wind W 5-15 MPH shifting to NW.

FRIDAY NIGHT: Mostly clear. Patchy ground fog lower elevation areas. Lows 55-62. Dew point middle 50s. Wind NW up to 10 MPH.

SATURDAY: Mostly sunny. Highs 76-83. Dew point upper 50s. Wind W 5-15 MPH.

SATURDAY NIGHT: Partly cloudy. Lower elevation fog patches. Lows 57-64. Dew point upper 50s. Wind W under 10 MPH.

SUNDAY: Variably cloudy. Chance of showers. Highs 76-83. Dew point lower 60s. Wind W 5-15 MPH.

SUNDAY NIGHT: Mostly cloudy. Chance of showers and possibly a thunderstorm. Patchy fog. Lows 62-69. Dew point lower to middle 60s.

MONDAY: Partly sunny. Chance of showers and possibly a thunderstorm, favoring the morning-midday hours. Highs 78-85. Dew point lower 60s. Wind W 5-15 MPH shifting to NW.

DAYS 6-10 (JULY 27-31)

A west to northwest air flow pattern will feature drier than average conditions and near to below normal temperatures, often seeing air coming from Canada. Best chance for an interrupting disturbance with showers around July 28-29.

DAYS 11-15 (AUGUST 1-5)

Overall pattern of west to northwesterly air flow, with no major heat, temperatures near to slightly below normal, and a drier overall regime with limited shower chances.

Wednesday July 21 2021 Forecast (7:52AM)

DAYS 1-5 (JULY 21-25)

Today, we still have the smoke in the atmosphere, both upper and lower, fairly high humidity, and a thunderstorm threat (for parts of the region). Tomorrow, we lose all of it and gain one of the nicest days of the summer. To get there, we have to go through a transition today as a disturbance moves across the region. Previous chatter was a little more inclusive of the entire region in a significant thunderstorm threat, but one must keep in mind that weather in the hours just before can impact weather in the hours just after, and if using short range models for guidance, it’s essential to watch trends on those as well as keeping track of what’s going on via surface obs. Last night, some of the convection from yesterday’s activity to the west survived its trip east, even a bit more so than I expected it to, and one thing this has done is to stabilize the atmosphere in a good part of the region north of I-90, and it is these areas that have the smaller risk of showers and storms today, just some isolated activity popping up early or mid afternoon. To the south, closer to where today’s disturbance will pass, and with less stable air, look for a little more in the way of shower and thunderstorm activity developing and moving in during the afternoon and into the evening. It is still quite possible that a few of these storms may become severe with damaging wind being the most significant threat, but also some chance of larger hail as well. All of this activity moves away later tonight and is replaced by a dry air mass from Canada. Even though a lot of our wild fire smoke has originated in Canada, the shift in the winds both surface and aloft will be enough to remove most of the smoke from our region, and Thursday should feature a deeper blue sky than we have seen in quite a while, not that we’ve seen much of any blue sky this month anyway. You may be wondering if this is temporary and we’re going right back to the pattern we’ve been in. Actually, not this time. The pattern is changing for now, and even though a disturbance has to swing through the region on Friday with some clouds and the threat of passing showers, we’ll be introduce to fresh Canadian air, part 2, on Saturday. But things are moving along and the next disturbance will be on the way by Sunday, once again with more cloudiness and the threat of some shower activity. The difference now is that we’re not seeing these frontal systems move in then sit around for a few days, creating stretches of unsettled weather…

TODAY: Mixed sun, clouds, and wildfire smoke. Isolated showers and thunderstorms north of I-90 midday through mid afternoon. Scattered showers and thunderstorms I-90 belt southward mid afternoon to early evening, with any thunderstorms potentially severe (hail, wind damage). Highs 77-84. Dew point middle to upper 60s. Wind W 5-15 MPH, variable and potentially stronger around storms.

TONIGHT: Partly cloudy. Lows 57-64. Dew point falling to middle 50s. Wind NW 5-15 MPH.

THURSDAY: Mostly sunny. Highs 76-83. Dew point upper 50s. Wind NW 5-15 MPH.

THURSDAY NIGHT: Partly cloudy. Lows 58-65. Dew point middle to upper 50s. Wind W under 10 MPH.

FRIDAY: Partly sunny. Chance of showers, mostly morning through midday. Highs 73-80. Dew point near 60. Wind W 5-15 MPH.

FRIDAY NIGHT: Mostly clear. Patchy ground fog lower elevation areas. Lows 55-62. Dew point falling to middle 50s. Wind NW up to 10 MPH.

SATURDAY: Mostly sunny. Highs 76-83. Dew point upper 50s. Wind W 5-15 MPH.

SATURDAY NIGHT: Partly cloudy. Lower elevation fog patches. Lows 57-64. Dew point upper 50s. Wind W under 10 MPH.

SUNDAY: Variably cloudy. Chance of showers. Highs 76-83. Dew point lower 60s. Wind W 5-15 MPH.

DAYS 6-10 (JULY 26-30)

A westerly air flow pattern will feature drier than average conditions and near to below normal temperatures, often seeing air coming from Canada. Best chance for an interrupting disturbance with showers mid period.

DAYS 11-15 (JULY 31 – AUGUST 4)

Overall pattern keeps us in a west to northwesterly air flow, with no major heat, temperatures near to slightly below normal, and a drier overall regime with fewer shower chances.

Tuesday July 20 2021 Forecast (7:28AM)

DAYS 1-5 (JULY 20-24)

The sunshine is back to start today, but it’s got a smoke screen – a high altitude one via Canadian and western US wildfires – nothing all that unusual for this time of year though. We’ll feel a bit of heat today today as we’re in a very warm air mass with moderate to high humidity. This may help fuel a couple isolated late day showers or thunderstorms, mainly west and north of Boston, which may still be around tonight as a disturbance moves through from the west. This sets up a potentially interesting day tomorrow, as a broad trough moves across the region with embedded disturbances, good for up to a few rounds of convection producing showers and thunderstorms. Some of the storms could potentially be strong to severe, so we’ll have to keep an eye on this during the day, anywhere from late morning to early evening. This system pushes off to the east at night, and we get a visit from Canadian high pressure bringing us the nicest day we’ve had in a while on Thursday. The next disturbance passes through the region Friday, but this one looks fairly weak and will only bring the chance of a few passing showers, mainly during the first half of the day as it stands now. Another area of high pressure brings nice weather back for Saturday.

TODAY: Smoke-filtered sun, eventually some clouds, and the chance of a late-day shower or thunderstorm mostly well north and west of Boston. Highs 80-87, cooler Cape Cod. Dew point upper 60s. Wind W 5-15 MPH.

TONIGHT: Variably cloudy with a chance of a shower or thunderstorm during the evening, then partly cloudy with patchy ground fog overnight. Lows 61-68. Dew point lower 60s. Wind W under 10 MPH.

WEDNESDAY: Variably cloudy. Episodes of scattered to numerous showers and thunderstorms. Some thunderstorms may become severe. Highs 76-83. Dew point middle to upper 60s. Wind W 5-15 MPH, variable and potentially stronger around storms.

WEDNESDAY NIGHT: Partly cloudy. Lows 57-64. Dew point falling to middle 50s. Wind NW 5-15 MPH.

THURSDAY: Mostly sunny. Highs 76-83. Dew point upper 50s. Wind NW 5-15 MPH.

THURSDAY NIGHT: Partly cloudy. Lows 58-65. Dew point middle to upper 50s. Wind W under 10 MPH.

FRIDAY: Partly sunny. Chance of showers, mostly morning through midday. Highs 73-80. Dew point near 60. Wind W 5-15 MPH.

FRIDAY NIGHT: Mostly clear. Patchy ground fog lower elevation areas. Lows 55-62. Dew point falling to middle 50s. Wind NW up to 10 MPH.

SATURDAY: Mostly sunny. Highs 76-83. Dew point upper 50s. Wind W 5-15 MPH.

DAYS 6-10 (JULY 25-29)

Westerly flow overall. Disturbances with shower chances somewhere in the July 25-26 and later July 27-28 time frames, but most of the time rain-free – a considerably drier pattern than recently. Temperatures near to below normal.

DAYS 11-15 (JULY 30 – AUGUST 3)

Overall pattern keeps us in a west to northwesterly air flow, with no major heat, temperatures near to slightly below normal, and a drier overall regime with fewer shower chances.

Monday July 19 2021 Forecast (7:30AM)

DAYS 1-5 (JULY 19-23)

The pattern we’ve been in – yes, that pattern, the one that delivers rain at least part of every day (except one so far this month) for at least parts of the WHW forecast area. Yes, that pattern is showing signs of departing us, but not during the next 5 days, so we still have to talk about it here. However, you will note there are a couple of better days to talk about. Not really today though, which will still be a cloudy, cooler one, with a foggy/drizzly start, and additional showers possible as we go through the day and upper level low pressure moves slowly across the region. And then this low exits tonight, and drier air arrives. Hey, Tuesday may be quite the nice day! It’ll be on the humid side, but the sun will shine for more of the day than many days we’ve had recently. Is there a chance of any rain on Tuesday? Well, yes. But this time it will only take the form of a few isolated sun + humidity driven showers that form during the afternoon, mostly in central MA and southern NH, and dissipate in the evening. So for most, Tuesday will be a rain-free day, and feeling quite a bit like the season it is as it warms into the 80s for most of the region with the exception of a few coastal areas, especially Cape Cod, but even there it will still be nice. But wait, we can’t string nice days together quite yet, so we have to talk about a cold front coming through the region on Wednesday with a better shower and thunderstorm threat. There’s some question on the timing of this front, or if much of the activity will form on a pre-frontal trough, leaving us with a quieter frontal passage after that. For now, just putting the chance of this activity in there for midday through afternoon, the fine-tuning from there. That front pushes offshore that night and a nice area of high pressure builds in for Thursday, which I am going to optimistically forecast as a dry day for the entire WHW area, with lower humidity. Pop up showers should stay in the mountains to our west and north, at least I think so. And again, no two nice days in a row allowed yet! So Friday, a low pressure trough swings through the region with another chance of showers, but the wet weather may be weighted more toward the first half of the day, based on current timing, so that day may be at least partially salvaged as nice…

TODAY: Overcast with areas of fog and drizzle during the morning hours. Mostly cloudy with scattered to numerous showers during the afternoon. Highs 70-77. Dew point middle to upper 60s. Wind N up to 10 MPH.

TONIGHT: Gradual clearing, but patchy ground fog. Lows 60-67. Dew point middle to lower 60s. Wind NW under 10 MPH.

TUESDAY: Mostly sunny morning. Partly sunny afternoon with isolated late day showers and thunderstorms possible mainly west of I-95. Highs 80-87 except cooler in some coastal areas especially Cape Cod. Dew point upper 60s to 70. Wind W 5-15 MPH.

TUESDAY NIGHT: Variably cloudy with a chance of a passing shower evening. Partly cloudy overnight. Patchy fog forming in lower elevations. Lows 60-67. Dew point falling to lower 60s. Wind W under 10 MPH.

WEDNESDAY: Variably cloudy. Scattered showers and thunderstorms. Highs 75-82. Dew point lower to middle 60s. Wind W 5-15 MPH.

WEDNESDAY NIGHT: Partly cloudy. Lows 57-64. Dew point falling to middle 50s. Wind NW 5-15 MPH.

THURSDAY: Mostly sunny. Highs 76-83. Dew point upper 50s. Wind NW 5-15 MPH.

THURSDAY NIGHT: Increasing clouds. Lows 58-65. Dew point middle to upper 50s. Wind W under 10 MPH.

FRIDAY: Variably cloudy. Chance of showers, ending later in the day. Highs 72-79. Dew point near 60. Wind W 5-15 MPH.

DAYS 6-10 (JULY 24-28)

Drier weather for July 24. Watching for the next low pressure system to bring a chance of some wet weather sometime in the July 25-26 time frame, but timing is uncertain, and another minor system around July 27-28, but this sounds worse than it is as these will be quick-moving systems with plenty of dry time these days as well. Temperatures near to slightly below normal for this period.

DAYS 11-15 (JULY 29 – AUGUST 2)

Overall pattern keeps us in a west to northwesterly air flow, with no major heat, temperatures near to slightly below normal, and a drier overall regime developing with fewer shower chances.

Your no-hype southeastern New England weather blog!