DAYS 1-5 (JULY 23-27)

A hot weekend is ours. No way around that, so find ways to stay cool if you can! The humidity will be a factor as well, less so today for much of the region with readings under 70, but some 70+ readings are present near the South Coast, and these will spread northward across most of the region for Sunday. You’ve heard talk of high temps near 100 for some places Sunday. While the temps may certainly get way into the 90s, a place like Boston is not likely to reach the century mark with a higher dew point and a wind blowing from the south and southwest, as is expected. The metro area gets its hottest weather when the dew point is lower and the wind is more west or even west northwest, so while the wind direction may prevent the higher temperature reading, it will help bring in the oppressive humidity. So either way you look at it, it’s going to be a hot weekend, though we may get through it without breaking any record temperatures – though a few may be challenged Sunday. I also think the thunderstorm threat will be absent as we are under the influence of weak high pressure and the warmer atmosphere aloft is a stabilizing influence. Things start to change later Sunday night and especially Monday as we bring a cold front into the region. Right now, the timing of this frontal boundary remains a little in question, and knowing this will help determine when thunderstorm threats are and how many rounds of them we may see. Keep in mind as you see the detailed forecast for that day that fine-tuning will be done and more detail added during the next couple days. Whether or not the 90+ temperatures are reached on Monday will depend on timing of front and amount of cloud cover. So Boston is a lock for a 6-day heatwave (through Sunday) as I see it, but not necessarily for a 7-day. Their record is 9 days in 1912, at which time the readings were taken in the city and not the current airport location. The airport location has recorded a few 8-day heatwaves (1944, 1994, and 2002). So those records are safe, because Tuesday’s temperatures (and dew points) will be down considerably behind that front as high pressure moves in with great summer weather as we head toward the middle of next week.

TODAY: Sunny. Highs 90-97, cooler South Coast. Dew point ranging from near 60 southern NH and northern MA to around 70 at the South Coast. Wind W 5-15 MPH.

TONIGHT: Partly cloudy. Patchy ground fog. Lows 68-75. Dew point middle 60s southern NH and northeastern MA to around 70 elsewhere. Wind SW up to 10 MPH.

SUNDAY: Mostly sunny. Highs 92-99, hottest in the Merrimack Valley region, cooler locations South Coast. Dew point lower to middle 70s, highest South Coast. Wind SW to SSW 5-15 MPH.

SUNDAY NIGHT: Variably cloudy. Chance of showers and thunderstorms, mainly late at night and favoring areas west and north of Boston. Patchy fog. Lows 72-79. Dew point 70+. Wind SW 5-15 MPH.

MONDAY: Variably cloudy. Chance of showers and thunderstorms, favoring morning to mid afternoon hours. Highs 85-92, cooler South Coast. Dew point 70+. Wind SW to W 5-15 MPH.

MONDAY NIGHT: Partly cloudy. Patchy fog mainly interior lower elevations. Lows 65-72. Dew point falling through 60s. Wind W 5-15 MPH.

TUESDAY: Mostly sunny. Highs 82-89. Dew point upper 50s. Wind W 5-15 MPH.

TUESDAY NIGHT: Mostly clear. Lows 60-67. Dew point 50s. Wind W up to 10 MPH.

WEDNESDAY: Mostly sunny. Highs 81-88. Dew point 50s. Wind variable up to 10 MPH with light coastal sea breezes.

DAYS 6-10 (JULY 28 – AUGUST 1)

Heat and humidity return for July 28 along with a chance of showers and thunderstorms with the approach and passage of a cold front. An area of high pressure should bring dry and seasonably warm weather July 29 on with some increase in humidity toward the end of the period as the high center sets up to the south of New England.

DAYS 11-15 (AUGUST 2-6)

Higher humidity spike early in the period including a chance of showers and thunderstorms, then drier air and seasonably warm weather following.

C-19 Chat Post – 7-23-2022

DAYS 1-5 (JULY 22-26)

Hot weather will continue through the weekend, but today and Saturday will have lower humidity than the sultry spike we experienced yesterday. While only limited locations saw thunderstorm activity yesterday afternoon and evening, you didn’t have to see one of those to get the benefit of the lower dew point air the front causing them has delivered to the region. Qualification: This is not a push of refreshing dry air from Canada, but it’s definitely less humid than yesterday, so it will be a slightly drier heat really. But that’s something, if you are not a fan of the higher humidity. Make the most of it? These two days will also feature fair weather as high pressure dominates, but just a tiny little atmospheric disturbance will be drifting across the region this evening, and that may be enough to allow a couple isolated showers and thunderstorms to at least approach the western reaches of the WHW forecast area in CT, MA, and southwestern NH, late this afternoon or this evening (reflected in the forecast below as a slight chance of a brief evening shower or storm). The humidity makes a come-back Sunday, and that will also be our hottest day of the stretch, as it is clearly obvious now that the next approaching front will not be quick enough to send cloudiness into the region sooner. So expect a Sunday scorcher – no way around it other than the slightly cooler air on South Coast beaches and especially Cape Cod due to the southwesterly wind blowing across ocean water before reaching these areas. The heat breaks for Monday, although the humidity will be slow to exit, as a cold front ambles its way across the region. This enables showers and thunderstorms to develop and be around for a good portion of the day, but I’m not expecting a widespread beneficial rain – just an unsettled day until the frontal boundary as cleared the region. Right now I expect this will happen at some point by mid to late afternoon, but I may have to tweak that timing on future forecast updates. Regardless, lower dew point and seasonably warm air will be ours by Tuesday.

TODAY: Sun with some passing clouds at times. An isolated shower or a thunderstorm is possible far north and west of Boston later in the day. Highs 88-95. Dew point middle to lower 60s. Wind W 5-15 MPH, few higher gusts at times.

TONIGHT: Partly cloudy evening with a slight chance of a shower or thunderstorm in southern NH, central MA, and far eastern CT. Mostly clear overnight. Lows 65-72. Dew point lower 60s. Wind W up to 10 MPH.

SATURDAY: Mostly sunny. Highs 90-97. Dew point 60s. Wind W 5-15 MPH.

SATURDAY NIGHT: Partly cloudy. Patchy ground fog. Lows 68-75. Dew point middle to upper 60s. Wind SW up to 10 MPH.

SUNDAY: Partly cloudy. A late-day thunderstorm possible southwestern NH and central MA. Highs 92-99, cooler South Coast. Dew point middle 60s to near 70, highest near the south coast. Wind SW 5-15 MPH.

SUNDAY NIGHT: Variably cloudy. Chance of showers and thunderstorms. Patchy fog. Lows 70-77. Dew point near 70. Wind SW 5-15 MPH.

MONDAY: Variably cloudy. Chance of showers and thunderstorms, favoring morning to mid afternoon hours. Highs 81-88. Dew point near 70. Wind SW to W 5-15 MPH.

MONDAY NIGHT: Partly cloudy. Patchy fog mainly interior lower elevations. Lows 65-72. Dew point falling into 60s. Wind W up to 10 MPH.

TUESDAY: Mostly sunny. Highs 82-89. Dew point upper 50s. Wind W 5-15 MPH.

DAYS 6-10 (JULY 27-31)

High pressure brings dry and seasonably warm weather 27. Heat/humidity returns with a chance of showers/t-storms on July 28. Another area of high pressure brings dry/warm weather for July 29-31, based on best guess at timing of systems at this point.

DAYS 11-15 (AUGUST 1-5)

Higher humidity spike early in the period including a chance of showers and thunderstorms, then drier air and seasonably warm weather following.

C-19 Chat Post – 7-22-2022

DAYS 1-5 (JULY 21-25)

The July hot spell continues and as far as “heatwave” by definition, those that started to build one Tuesday should see it become official today as I think most of the region goes 90+ for temperature today. There will be the usual exceptions (parts of Cape Cod and the Islands, and maybe a few portions of the irregular coastline), but the general idea is we get to heatwave status today and then keep it going at least through Saturday. Our wildcard day is Sunday, which has the potential to be the hottest day based on current expecting timing of an approaching front and its cloudiness, because despite the higher heat potential, if that system ended up arriving more quickly than expected, parts of our area could still end up falling short of 90. Either way, that system should break the heatwave by Monday for at least most areas. But before we get there, we have a bit of a thunderstorm threat for today. This will be triggered by an approaching cold front, fairly weak in terms of the fact it won’t break our heat, but it will take the humidity, which spikes today, down a few notches for the end of the week. While any time you have a cold front slicing into a hot / humid air mass you have to be on the look-out for storms, I don’t think today’s activity will end up producing a sweeping line that gets everybody, but rather a cluster or two (maybe line segments) of storms that form to our west and northwest, then make their way into portions of the WHW forecast area, especially southern NH and central to northeastern MA, later in the day and for part of this evening. But as you go southeast, the support for storms will be more lacking, and I don’t think they will really survive the trip to impact many areas south of I-90 and especially toward the eastern coastal locations from near Boston southward. Something to keep an eye on of course, because thunderstorms can often have “a mind of their own” and defy what our short range guidance tells us they are going to do, but this is my general thinking and we will monitor the activity later today to see what the result ends up being. For caution, the two things to be concerned about today are protecting yourself from the heat (limit outdoor time if possible, and stay hydrated!) and watch for the late-day storm threat. We’ll have a warm and muggy night tonight, even areas that would get some temporary cooling from a storm, but slightly drier air will flow in overnight / early Friday behind that weak front, and even though it will be a hot day on Friday again, the dew point, which is in the lower 70s for many of us today, will be back under 70 and maybe even down to the lower and middle 60s for Friday. Over the weekend, we do stay hot, and the humidity remains barely manageable Saturday but may spike Sunday ahead of the next approaching front. So combined with the higher heat potential, Sunday may be the most dangerous day, heat-wise, of this stretch. I’ll assess the thunderstorm threat for Sunday-Monday as we get closer to that time, but for now it looks like we get through Sunday daytime without much of anything, then will have to watch for some activity Sunday night and the first half of Monday before the front sweeps through. Cloud cover and incoming “cooler” air should prevent 90s from occurring Monday as it stands now, breaking the heatwave.

TODAY: Sun/cloud mix. Isolated to scattered thunderstorms later afternoon / evening favoring southern NH and northern MA. Any storms can be locally severe with hail and wind damage. Highs 88-95. Dew point lower 70s. Wind SW increasing to 10-20 MPH, can be variable, strong, and gusty near any storms.

TONIGHT: Variably cloudy with a chance of showers and thunderstorms early, then clearing. Lows 66-73. Dew point falling into 60s. Wind W 5-15 MPH.

FRIDAY: Sun and passing clouds. Highs 88-95. Dew point 60s. Wind W 5-15 MPH, a few higher gusts.

FRIDAY NIGHT: Mostly clear. Lows 65-72. Dew point 60s. Wind W 5-15 MPH.

SATURDAY: Mostly sunny. Highs 90-97. Dew point 60s. Wind W 5-15 MPH.

SATURDAY NIGHT: Partly cloudy. Patchy ground fog. Lows 68-75. Dew point middle to upper 60s. Wind SW up to 10 MPH.

SUNDAY: Partly sunny. Possible late-day showers and thunderstorms favoring western areas. Highs 92-99, cooler South Coast. Dew point near 70. Wind SW 5-15 MPH.

SUNDAY NIGHT: Variably cloudy. Chance of showers and thunderstorms. Patchy fog. Lows 70-77. Dew point near 70. Wind SW 5-15 MPH.

MONDAY: Variably cloudy. Chance of showers and thunderstorms, favoring morning-midday hours. Highs 81-88. Dew point near 70. Wind SW to W 5-15 MPH.

DAYS 6-10 (JULY 26-30)

High pressure brings dry and seasonably warm weather July 26-27. Heat/humidity returns with a chance of showers/t-storms on July 28. Another area of high pressure brings dry/warm weather for July 29-30. Confidence on this timing is not high at this point, but this is a best-guess.

DAYS 11-15 (JULY 31 – AUGUST 4)

Typical mid summer pattern. Warm to hot, a few shower/t-storm chances, rain-free most of time.

C-19 Chat Post – 7-21-2022

DAYS 1-5 (JULY 20-24)

It’s the climatological hottest time of the year, and we’ll be talking about heat, right on schedule. For many locations, a solid heatwave is underway. Several locations, especially coastal areas, may escape it with a day or two during the next 5 failing to reach 90. Our saving grace is that the dew point, while high enough to make it “humid”, will stay below the threshold of “oppressive” most of the time, only reaching it Thursday and later Sunday as it looks now. Much of the other time, we have enough air mixing going on to bring drier air down from aloft via the down-slope effect so that most of if not all of the WHW forecast area keeps dew points below 70, and in the case of Friday, behind a cold front, down around 60. That cold front represents our only real chance of any rainfall during the next few days, in the form of showers and thunderstorms Thursday afternoon and evening. Some of these can be strong to locally severe, but right now the coverage looks as if it may be limited. This will be monitored and fine-tuned during the next 48+ hours. The next shot of some shower and thunderstorm activity would be later Sunday with the approach of another front.

TODAY: Partly cloudy. Highs 88-95. Dew point middle to upper 60s. Wind WSW 5-15 MPH.

TONIGHT: Partly cloudy. Fog patches interior low elevations. Lows 65-72. Dew point middle to upper 60s. Wind SW under 10 MPH.

THURSDAY: Partly sunny. Chance of showers and thunderstorms mid afternoon on, especially west of I-95. Highs 87-94. Dew point rising to lower 70s. Wind SW 10-20 MPH.

THURSDAY NIGHT: Variably cloudy with a chance of showers and thunderstorms early, then clearing. Lows 63-70. Dew point falling to near 60. Wind NW 5-15 MPH.

FRIDAY: Sun and passing clouds. Highs 85-92. Dew point near 60. Wind W 5-15 MPH.

FRIDAY NIGHT: Mostly clear. Lows 65-72. Dew point near 60. Wind W 5-15 MPH.

SATURDAY: Mostly sunny. Highs 88-95. Dew point lower to middle 60s. Wind W 5-15 MPH.

SATURDAY NIGHT: Partly cloudy. Patchy ground fog. Lows 68-75. Dew point middle to upper 60s. Wind SW up to 10 MPH.

SUNDAY: Partly sunny. Possible afternoon showers and thunderstorms. Highs 86-94. Dew point near 70. Wind SW 5-15 MPH.

DAYS 6-10 (JULY 25-29)

Cold front passes with a chance of showers/thunderstorms early July 25, then drying and seasonably warm weather later July 25 through July 27. Increasing heat and humidity later in the period along with a chance of showers and thunderstorms by the end of the period, projecting timing of features several days in advance.

DAYS 11-15 (JULY 30 – AUGUST 3)

A similar pattern overall with mostly above normal temperatures and limited rainfall opportunities.

C-19 Chat Post – 7-20-2022

DAYS 1-5 (JULY 19-23)

The first, and so far only, stretch of hot weather this summer begins today as high pressure takes up residence to our south and pumps Midwestern heat into our region. While this is not a classic upper air set-up we see for a lot of our hot episodes, the central US has been hot for quite a while and the source region of our incoming air during this time will be more than adequate for a supply. The pattern having a southwesterly air flow and keeping us slightly in a mean trough position also means that we’ll be able to mix the atmosphere up more, which includes transporting drying air via the downsloping effect from the mountains to our west, keeping dew points from reaching what they may have if we were in a Bermuda High set-up. That doesn’t mean we won’t have our episodes of higher humidity. It just won’t persist. So it will be hotter today and definitely hot Wednesday and Thursday, with highest humidity of the 3 days being Thursday, just ahead of a cold front. This front brings the only shot of showers and thunderstorms for the WHW forecast area during this 5 day period, as slightly drier air follows that and the chance of any convective activity vanishes late this week (Friday-Saturday).

TODAY: Sun and passing clouds. Highs 85-92. Dew point lower to middle 60s. Wind W 5-15 MPH, higher gusts.

TONIGHT: Partly cloudy. Lows 65-72. Dew point lower 60s. Wind W 5-15 MPH.

WEDNESDAY: Partly cloudy. Highs 87-94. Dew point middle to upper 60s. Wind WSW 5-15 MPH.

WEDNESDAY NIGHT: Partly cloudy. Fog patches interior low elevations. Lows 65-72. Dew point middle to upper 60s. Wind SW under 10 MPH.

THURSDAY: Partly sunny. Chance of showers and thunderstorms late in the day. Highs 87-94. Dew point near 70. Wind SW 10-20 MPH.

THURSDAY NIGHT: Variably cloudy with a chance of showers and thunderstorms early, then clearing. Lows 63-70. Dew point falling to near 60. Wind NW 5-15 MPH.

FRIDAY: Sun and passing clouds. Highs 85-92. Dew point near 60. Wind W 5-15 MPH.

FRIDAY NIGHT: Mostly clear. Lows 65-72. Dew point near 60. Wind W 5-15 MPH.

SATURDAY: Mostly sunny. Highs 86-93. Dew point lower 60s. Wind W 5-15 MPH.

DAYS 6-10 (JULY 24-28)

A fairly typical summer pattern will dominate our weather during this time. We will see a couple opportunities for showers and thunderstorms, favoring later July 24 to early July 25 and sometime later in the period too. Temperatures above normal. Highest humidity July 24 and later in the period, lower humidity episode between.

DAYS 11-15 (JULY 29 – AUGUST 2)

A similar pattern overall with mostly above normal temperatures and limited rainfall opportunities.

C-19 Chat Post – 7-19-2022

DAYS 1-5 (JULY 18-22)

We sit about half way through meteorological summer, but are only about 1/3 of the way into “actual summer”, so either way you look at it, we have a lot of summer ahead of us. Up to this point, hot weather has been largely absent. The period from mid June to mid July ran slightly below normal in temperature, and our rainfall deficit continues with a building drought. During this week, we’ll see more heat than we’ve seen so far, and while we have a couple unsettled days in the forecast, we won’t be seeing any drought-busting rainfall. In fact, I full expect the drought to continue to build with the limited rainfall chances and the increase in the heat. We start today with a low pressure area approaching the region, the center of which will pass to our north tonight. This system will push a warm front across the area during this afternoon with a round of showers (most widespread to the northwest of the WHW forecast area though), and the cold front coming along tonight will produce a round or two of showers and possible thunderstorms. We’ll have a spike of high humidity while we’re in the warm sector of this system, but it will really only be with us for a few hours. Drier air settles in behind the cold front Tuesday, but “cold front” is relative, as the air mass behind this system is actually warmer than the one ahead of it, so it’ll be quite a warm day, but with fair weather dominating as high pressure approaches the region. Many times over the last several weeks when a system like this would go by, we’d get a push of cooler air from Canada. The pattern this week is not going to be like that, and our air will be coming from a hotter source region. High pressure will continue to control the weather Wednesday with very warm to hot conditions but only moderate humidity, and no threat of rain. The high will push offshore early Thursday when a warm front quietly goes through the region, and that will be the day we combine heat with higher humidity, ahead of an approaching cold front. This front will trigger some shower and thunderstorm activity during the afternoon and evening as it approaches and passes by the region. As for coverage and intensity of those, we’ll have to keep an eye on it and detail it as it gets closer. Behind this system, the very warm weather remains but the humidity drops off for Friday, with fair weather expected.

TODAY: Clouding over this morning. Cloudy with a round of rain and possible embedded heavier showers and isolated thunderstorms first half of afternoon. Mostly cloudy with isolated showers possible second half of afternoon / early evening. Highs 77-84. Dew point rising through 60s. Wind S-SW 5-15 MPH, higher gusts this afternoon.

TONIGHT: Mostly cloudy through late evening and early overnight with showers and thunderstorms including areas of fog. Greatest chance of thunderstorms in central Massachusetts and southern New Hampshire. Any storms could be locally strong to severe. Breaking clouds / clearing west to east toward dawn. Lows 63-70. Dew point near 70 evening, falling toward 60 overnight. Wind SW 5-15 MPH, higher gusts above 20 MPH and up to 30 MPH in some portions of the South Coast as well as near any storms, shifting to W from west to east overnight.

TUESDAY: Mostly sunny. Highs 85-92. Dew point upper 50s. Wind W 5-15 MPH.

TUESDAY NIGHT: Partly cloudy. Lows 64-71. Dew point near 60. Wind W up to 10 MPH.

WEDNESDAY: Partly cloudy. Highs 87-94. Dew point rising into 60s. Wind SW 5-15 MPH.

WEDNESDAY NIGHT: Partly cloudy. Fog patches interior low elevations. Lows 65-72. Dew point middle to upper 60s. Wind SW under 10 MPH.

THURSDAY: Partly sunny. Chance of showers and thunderstorms late in the day. Highs 87-94. Dew point near 70. Wind SW 10-20 MPH.

THURSDAY NIGHT: Variably cloudy with a chance of showers and thunderstorms early, then clearing. Lows 63-70. Dew point falling to 50s. Wind NW 5-15 MPH.

FRIDAY: Sun and passing clouds. Highs 85-92. Dew point 50s. Wind W 5-15 MPH.

DAYS 6-10 (JULY 23-27)

A fairly typical summer pattern will dominate our weather during this time. We will see a couple opportunities for showers and thunderstorms, favoring later July 24 to early July 25 and sometime later in the period too. It’s difficult to time such opportunities this far in advance so the usual fine-tuning will take place. Expect the temperature to average near to above normal. Higher humidity at times, but not likely for the entire period.

DAYS 11-15 (JULY 28 – AUGUST 1)

A similar pattern overall, but may see a little more dry air push from Canada at some point.

C-19 Chat Post – 7-18-2022

DAYS 1-5 (JULY 17-21)

The big picture: Only 2 unsettled days out of the next 5 (maybe more), and introducing more heat into the mix means the drought likely expands more quickly in the days ahead, even with a couple threats of heavy downpours. The day-to-day picture: Today will generally be a great summer day, although patchy clouds are in some areas early and mostly-fair-weather clouds will pop up during the day, but we won’t have that sun-filtering high cloud shield today. Humidity will be on the rise, but not rapidly, although those sensitive will notice it. Like yesterday, there is the tiniest chance regionwide of a pop-up shower or thunderstorm from a couple of the developing cumulus clouds today, but in general this is a fair weather day for our region, extending through tonight as well. Monday is the first of the two aforementioned unsettled days, as a low pressure disturbance will be moving eastward across the Northeast. We first see a round of showers with a warm front during midday and part of the afternoon, followed by a batch of showers and thunderstorms with the system’s cold front in the evening. Initially, some of our guidance painted this as a widespread moderate to heavy rain event lasting many hours, but as you have been cautioned, this is often the type of system that is over-forecast by guidance, and when it gets here, it ends up being a shorter-duration rain event, as you see in this case, with just a couple rounds of showers and storms, but the threat of some downpours with heavy rainfall. But “heavy rain” does not really mean beneficial rain, and in this case any drought relief brought by this system will be quite limited. It’s short-duration, and will be followed by two dry and rather warm to hot days Tuesday and Wednesday. Unlike many previous events, we don’t get a push of cooler/dry air from Canada behind the disturbance, but our air will come from a hotter source region in the middle of the US, so we’ll feel the heat of July coming on into the region. Tuesday’s and Wednesday’s weather is expected to be rain-free regionwide. Thursday, our heat stays with us and humidity spikes back up ahead of a cold front, which brings the chance of showers and thunderstorms again. The coverage, intensity, and timing of this activity is yet to be determined, and will depend on specifics which I can nail down over the next few days.

TODAY: Sun/cloud mix. Slight chance of an isolated afternoon shower or thunderstorm. Highs 83-90. Dew point rising through 60s. Wind S-SW up to 10 MPH.

TONIGHT: Partly cloudy. Patchy fog. Lows 65-72. Dew point middle to upper 60s. Wind S up to 10 MPH.

MONDAY: Partly sunny early, otherwise mostly cloudy. Showers likely midday through mid afternoon. Highs 77-84. Muggy – dew point upper 60s to lower 70s. Wind S-SW 5-15 MPH.

MONDAY NIGHT: Mostly cloudy with showers and thunderstorms likely evening. Partly cloudy overnight. Areas of fog. Lows 62-69. Dew point falling slowly through 60s.Wind SW up to 10 MPH shifting to W, but winds can be variable and gusty near any storms.

TUESDAY: Partly cloudy. Highs 84-91. Dew point near 60. Wind W 5-15 MPH.

TUESDAY NIGHT: Partly cloudy. Lows 63-70. Dew point near 60. Wind W up to 10 MPH.

WEDNESDAY: Partly cloudy. Highs 87-94. Dew point rising through 60s. Wind SW 5-15 MPH.

WEDNESDAY NIGHT: Partly cloudy. Fog patches interior low elevations. Lows 65-72. Dew point middle to upper 60s. Wind SW under 10 MPH.

THURSDAY: Partly sunny. Chance of showers and thunderstorms especially afternoon. Highs 87-94. Dew point near 70. Wind SW 10-20 MPH.

DAYS 6-10 (JULY 22-26)

Less humid, rain-free but still very warm to hot weather July 22-23 as high pressure dominates. Shower and thunderstorm threat increases July 24 to early July 25 as a trough and frontal system move across the region before slightly drier but still very warm weather dominates the end of the period.

DAYS 11-15 (JULY 27-31)

July should come down its home stretch in a pattern that transitions from warm to hot and humid with a shower and thunderstorm threat early in the period to drier but warm weather with high pressure dominating later in the period.

C-19 Chat Post – 7-17-2022

DAYS 1-5 (JULY 16-20)

This weekend will give us not only very nice summer weather (not perfect) but also another lesson on the limitations of even our shorter-range guidance. As recently as yesterday, forecasts both here and around media called for a mostly sunny sky today, and while the sun will shine often today, it will also be filtered and dimmed quite often by a large shield of high cloudiness crossing our sky, born of convective activity in the Midwest. Also, some lower level moisture helped a bank of broken lower clouds form near the South Coast, which will dissipate as the morning goes on. But also, we have a little previously-not-really-detected-by-guidance disturbance that has to cross the region during the day today, and you’ll see evidence of that by cumulus clouds building up this morning into part of the afternoon underneath the high cloud shield. One or two of these clouds may grow large enough to release isolated showers. I would certainly not cancel any outdoor plans over this minor threat, but I would keep an eye on the sky just in case. That disturbance is gone later today and yet another one crosses the region tonight, keep the sky more cloud-filled than clear, and once again a spot shower can’t be ruled out, but it’s unlikely that any specific location will see one. The other change to the short term forecast is the ability to remove the shower and thunderstorm threat from the daytime and evening hours of Sunday – a day which will feature brighter sun than today, though still some clouds popping up to blot it out at times as well. Today’s humidity levels will be low enough to be deemed comfortable, but tomorrow’s dew point heads into higher territory, which will be noticeable. However, the more significant spike in humidity comes during Monday, especially in the afternoon, when a warm front crosses the region, preceded by a round of showers. Then a cold front approaches later in the day into the evening when a round of showers and thunderstorms is most likely. Advertisements of a widespread soaking rainfall with that system are probably over-selling the system’s capability to produce that. Now keeping in mind that even the short range guidance can struggle with these details, the tendency for quite some time now has been for the guidance to over-forecast the precipitation a few days out only to come back to reality as we get closer. That trend seems to be underway now, and while some heavy rainfall is certainly a strong possibility in the form of downpours / t-storms, a widespread beneficial rainfall would be one that would occur at a slower rate over a longer time, and I don’t see that as likely with that particular system. Behind it, we stay warm for Tuesday with a lowering of humidity and the return of fair weather after the chance of an early-in-the-day shower. A weak area of high pressure to the south of the region will provide fair weather into Wednesday as well, but since behind Monday’s system we’re not getting a shot of cooler/dry Canadian air that takes longer to kick out and modify, we’ll already be very warm to hot with more humid conditions again by midweek. At day 5, I can’t be confident of calling for a pop up air mass shower or thunderstorm Wednesday, but I won’t rule it out.

TODAY: Variably cloudy. Very slight chance of a passing shower midday to mid afternoon, favoring central and northeastern MA and southern NH. Highs 80-87, coolest coast. Dew point upper 50s. Wind S-SE up to 10 MPH.

TONIGHT: Variably cloudy. Lows 61-68. Dew point near 60. Wind S-SW up to 10 MPH.

SUNDAY: Partly cloudy. Highs 83-90. Dew point rising to middle to upper 60s. Wind S-SW up to 10 MPH.

SUNDAY NIGHT: Partly to mostly cloudy. Patchy fog. Lows 65-72. Dew point middle to upper 60s. Wind S up to 10 MPH.

MONDAY: Mostly cloudy. Showers likely midday through mid afternoon. Showers/thunderstorms likely late afternoon or evening from west to east. Highs 78-85. Dew point upper 60s rising to lower 70s. Wind S-SW 5-15 MPH.

MONDAY NIGHT: Variably cloudy. A chance of showers and thunderstorms. Areas of fog. Lows 62-69. Dew point falling slowly through 60s.

TUESDAY: Partly cloudy. Highs 83-90. Dew point near 60. Wind W 5-15 MPH.

TUESDAY NIGHT: Partly cloudy. Lows 63-70. Dew point near 60. Wind W up to 10 MPH.

WEDNESDAY: Partly cloudy. Highs 86-93. Dew point rising through 60s. Wind SW 5-15 MPH.

DAYS 6-10 (JULY 21-25)

Warm to hot weather July 21-22 with highest humidity and greatest chance of thunderstorms July 21 as a disturbance passes just to the north and drags a frontal boundary across the region, then a reduced storm chance July 22. Weak high pressure should keep shower and storm chances limited while we are warm to hot and have moderate humidity for the July 23-24 weekend and higher humidity again to end the period. This is not the classic Bermuda High set-up though as high pressure in the western Atlantic is to be weaker than one sitting over the east central US sending the hotter weather our way from the west southwest. We’ll actually find ourselves in a mean trough position here, albeit weak, so we end up with the warmth and see Canadian air masses unable to enter the region for a while.

DAYS 11-15 (JULY 26-30)

Unsettled weather episodes should be brief around the time of air mass changes, which will not be dramatic, as the overall pattern will be controlled by high pressure and a westerly to southwesterly air flow with mostly rain-free weather and near to above normal temperatures. We may get a push of drier air from Canada before the end of the period.