Wednesday June 30 2021 Forecast (7:31AM)

DAYS 1-5 (JUNE 30 – JULY 4)

On this final day of June we will also experience the final day of high heat and humidity in this early summer stretch of it. Unlike the last 2 days, today carries a risk of more regional thunderstorm activity as a cold front approaches. The timing looks a little later on this today, with the primary threat for the WHW forecast area coming in the 4PM through 9PM time frame from northwest to southeast. There can be a couple isolated shower or storms popping up ahead of that threat window, as early as 2PM or so. The greatest threat for severe weather is damaging wind with the storms. Small hail is a potential, along with the usuals: heavy downpours, lightning. If a storm cluster forms and trains over the same area for a while, which is possible, then flash flooding would become a threat, so we’ll have to watch for this as well. If you plan to be outside today into this evening, obviously plan for both the high heat and humidity and watch for approaching or developing storms – and have a plan! Once we get by this threat tonight, the cold front that delivers it will also deliver slightly cooler and less humid air, but only down a little bit, and as the front washes out over far southern New England Thursday we’ll still feel a bit of humidity and it will be a warm day, but we’ll be dealing with a lot more high and mid level cloudiness than we’ve seen during the last few days. An influx of moisture will head northeastward toward our region Thursday night while a second frontal boundary pushes through from the north. This front may trigger a few more showers and thunderstorms in the region Thursday afternoon, and the combination of it and the moisture arriving from the southwest is expected to bring more widespread showers to the region later Thursday night into a portion of Friday, before we see a drying trend north to south, along with much cooler air this time. High pressure from Canada will push the unsettled weather further south as we reach the holiday weekend, but upper level low pressure will still be stretched out across the region and will take a good deal of time to depart, so at this point I cannot rule out some scattered shower activity Saturday and isolated showers for Sunday. As far as the actual weekend goes, humidity levels will be quite manageable, and Saturday will be the cooler of the two days with a general northeasterly flow. The wind should be variable then eventually more westerly on Sunday allowing for a bit of a warm up to get underway.

TODAY: Early clouds north central MA and southern NH otherwise mostly sunny through midday. Partly to variably cloudy this afternoon and evening with isolated showers and thunderstorms possible by mid afternoon, then scattered to numerous showers and thunderstorms from northwest to southeast later afternoon and evening. Thunderstorms can become severe. Highs 88-95, cooler South Coast.. Dew point upper 60s to lower 70s. Wind SW 5-15 MPH, higher gusts.

TONIGHT: Variably cloudy evening with showers and thunderstorms favoring eastern and southern areas. Partly cloudy with patchy ground fog forming overnight. Lows 67-74. Dew point upper to middle 60s. Wind variable up to 10 MPH.

THURSDAY: Variably cloudy but some sunshine. Highs 75-80 South Coast, 80-85 elsewhere. Dew point middle 60s. Wind variable 5-15 MPH.

THURSDAY NIGHT: Cloudy. Numerous showers. Chance of thunderstorms. Areas of fog. Lows 60-67. Dew point falling to near 60. Wind variable 5-15 MPH becoming N to NE.

FRIDAY: Mostly cloudy. Chance of showers, especially CT, RI, southern MA. Highs 68-75. Dew point near 60. Wind NE 5-15 MPH

FRIDAY NIGHT: Mostly cloudy. Lows 55-62.Wind NE 5-15 MPH.

SATURDAY: Partly sunny. Scattered showers possible, favoring central MA, eastern CT, and RI. Highs 65-70 coast, 70-75 inland. Wind NE 5-15 MPH.

SATURDAY NIGHT: Partly cloudy. Lows 56-63. Wind NE up to 10 MPH becoming variable.

SUNDAY: Partly sunny. Isolated afternoon showers possible, mainly southwestern NH and central MA. Highs 75-82. Wind variable to W 5-15 MPH.

DAYS 6-10 (JULY 5-9)

Warmer slightly more humid with a chance of a few showers and thunderstorms later July 5 and again July 6 with a couple disturbances passing by. Mostly fair and seasonable weather mid to late period with weak high pressure in control, but this remains a low confidence forecast.

DAYS 11-15 (JULY 10-14)

Near to above normal temperatures and an increase in humidity but with a slightly better chance of showers and thunderstorms as a frontal boundary hangs out in the region.

Tuesday June 29 2021 Forecast (7:23AM)

DAYS 1-5 (JUNE 29 – JULY 3)

The next 5 days will be a good example of the range of temperatures we can see in the summertime, with a hot spell peaking today, backing off ever-so-slightly tomorrow, then ending as July arrives landing us on the cooler end of the spectrum by the end of the work week / start of the holiday weekend. Our Bermuda High continues to pump the heat and humidity into the region today. The atmosphere this afternoon will be very slightly more unstable than it was yesterday, so there is a slightly better chance that some isolated shower and thunderstorm activity will occur in the WHW forecast area this afternoon, where it stayed well west and north of the area yesterday. Most locations see nothing of the kind, but those who do can experience a torrential downpour and of course lightning as the cell peaks. These tend to last a short-time before raining themselves out. So while they are not highly likely, be on the look-out if you are out and about this afternoon. And most importantly, remember your heat precautions and safety measures! A cold front will be getting closer to the region later Wednesday, which will still be a hot and humid day, but with a better chance of at least scattered to possibly linear or segmented lines of showers and thunderstorms developing and arriving in the region later in the day. A slightly slower front would keep this activity mostly to the west and north – something to watch. The initial frontal boundary does get into the area Thursday, but in a dissipating state, and that day will still be humid though not as hot, with a pop up shower or thunderstorm possible with some solar heating. Later in the day expect more substantial cloud cover to take over as we start to see another front coming down from the northwest while some overrunning of tropical moisture starts to take place over the air mass boundaries. Some of this moisture will be from what was called a tropical storm as it quickly formed and made landfall in the US Southeast Monday. This could help produce a period of widespread and potentially heavy shower activity Thursday night and part of Friday, before it pulls away and we’re just left with some lingering showers favoring southern areas Friday, and much cooler air. High pressure from Canada is expected to have enough push to dry the region out but keep it on the cool side for the start of the holiday weekend on Saturday. There is still some medium range guidance that highly disagrees with this scenario, keeping the weather wet.

TODAY: Mostly sunny to partly cloudy. Isolated showers and thunderstorms possible from mid afternoon to early evening. Highs 90-97, cooler South Coast. Dew point near 70, may fall to middle 60s. Wind SW to W 5-15 MPH, higher gusts.

TONIGHT: Partly cloudy to mostly clear. Lows 68-75. Dew point upper 60s. Wind WSW 5-15 MPH.

WEDNESDAY: Partly sunny. Chance of afternoon showers and thunderstorms. Highs 87-94, cooler South Coast.. Dew point upper 60s to 70. Wind SW 5-15 MPH, higher gusts.

WEDNESDAY NIGHT: Partly cloudy. Chance of evening showers. Patchy fog. Lows 67-74. Dew point upper 60s. Wind variable up to 10 MPH.

THURSDAY: Partly sunny. Chance of showers and thunderstorms. Highs 82-89, cooler South Coast.. Dew point upper to middle 60s. Wind variable 5-15 MPH.

THURSDAY NIGHT: Cloudy. Numerous showers. Chance of thunderstorms. Areas of fog. Lows 60-67. Dew point falling to near 60. Wind variable 5-15 MPH becoming N to NE.

FRIDAY: Mostly cloudy. Chance of showers, especially CT, RI, southern MA. Highs 68-75. Dew point near 60. Wind NE 5-15 MPH

FRIDAY NIGHT: Mostly cloudy. Lows 55-62.Wind NE 5-15 MPH.

SATURDAY: Partly sunny. Highs 65-70 coast, 70-75 inland. Wind NE 5-15 MPH.

DAYS 6-10 (JULY 4-8)

The idea of high pressure from Canada coming down over the weekend remains, and if it’s correct we should see mostly fair weather and slight warming for July 4, but some upper level low pressure not far away can trigger some afternoon showers and thunderstorms. A shot of heat and a little higher humidity for July 5 which is counting as the holiday for some, along with a chance of showers and thunderstorms later as a front approaches from the west. If the timing of that system is slower, we’d get by that day without a real storm threat and the next day (July 6) would be more unsettled, followed by a drying trend by the middle of next week. Confidence on this time period is lower than average, so check updates.

DAYS 11-15 (JULY 9-13)

Near to above normal temperatures and an increase in humidity but with somewhat limited shower and thunderstorm chances. to start then increased later in the period as a frontal boundary to the north starts to drift southward into the region. Impossible for daily details this far out.

Monday June 28 2021 Forecast (7:21AM)

DAYS 1-5 (JUNE 28 – JULY 2)

The story will be the hot and humid weather for the first 3 days of this week, which are also the final 3 days of June. Please keep in mind as we get to the end of this month and you start hearing data via media for Boston, that the thermometer where official records are kept has been reading 2 degrees too high for the entire month, so the average will also be skewed by 2 degrees in that direction. It’ll be billed as the hottest June on record there, yet likely wasn’t. A warm June? Yes, most certainly. But we also had some cool days in there too. Bottom line: Not a brutal June, but a hot stretch early in the month and another hot stretch to end it. The Bermuda High will continue to do its thing into Wednesday and our only chance of seeing any rainfall before then will be from isolated air mass showers and thunderstorms that have a remote chance of popping up in a couple locations mainly well west of Boston today and a very slightly better chance of doing it tomorrow anywhere, but mostly west and north of a Boston-Providence line. These will be the vast exception and far from the rule, but if one does occur where you are, you can experience a torrential downpour along with briefly gusty wind and of course lightning and thunder, so if you are out and about, just know that even though quite low the chance, it’s not a 0% chance. On Wednesday, the shower and thunderstorm chance will increase, and the timing and placement of activity is going to be highly dependent on the location and movement of a cold front moving in from the northwest. It will take a couple days to nail down the timing and the day-of to start focusing on specific threats. Either way, Wednesday will still be a hot and humid day before any activity moves in. There’s been a difference of opinion between myself and much of the guidance for how the second half of this week plays out, but here are my current ideas on it. The cold front that approaches later Wednesday gets into southern New England by Thursday but starts to wash-out or fall apart and a second front drops down from the northwest later Thursday through early Friday. This brings the opportunity for a couple rounds of showers and thunderstorms Thursday, with still very warm and humid air in place, and as a little wave of low pressure moves along the front as it sits just to the south on Friday, some additional showers may occur, along with temperatures that will then be much cooler than they were for the first few days of the week. Before Friday is over, we may see a distinct dry-out and end to the shower threat from north to south. This has weekend implications, but we’ll get to that in the next sections. First, the details for the next 5…

TODAY: Mostly sunny to partly cloudy. Very slight risk of a late-day shower or thunderstorm well west of Boston. Highs 88-95. Dew point upper 60s to 70. Wind SW 5-15 MPH, higher gusts.

MONDAY NIGHT: Partly cloudy to mostly clear. Lows 68-75. Dew point upper 60s. Wind SW up to 10 MPH.

TUESDAY: Mostly sunny to partly cloudy. Slight chance of isolated late-day showers and thunderstorms mainly northwest of a Boston-Providence line. Highs 90-97, cooler South Coast. Dew point falling to middle 60s. Wind WSW 5-15 MPH, higher gusts.

TUESDAY NIGHT: Partly cloudy to mostly clear. Lows 68-75. Dew point middle 60s. Wind WSW 5-15 MPH.

WEDNESDAY: Partly sunny. Chance of afternoon showers and thunderstorms. Highs 87-94, cooler South Coast.. Dew point upper 60s to 70. Wind SW 5-15 MPH, higher gusts.

WEDNESDAY NIGHT: Partly cloudy. Chance of evening showers. Patchy fog. Lows 67-74. Dew point upper 60s. Wind variable up to 10 MPH.

THURSDAY: Partly sunny. Chance of showers and thunderstorms. Highs 82-89, cooler South Coast.. Dew point upper to middle 60s. Wind variable 5-15 MPH.

THURSDAY NIGHT: Mostly cloudy. Chance of showers. Areas of fog forming. Lows 60-67. Dew point falling to near 60. Wind variable 5-15 MPH becoming N to NE.

FRIDAY: Mostly cloudy. Chance of showers, especially CT, RI, southern MA. Highs 68-75. Dew point near 60. Wind NE 5-15 MPH

DAYS 6-10 (JULY 3-7)

There’s been a disagreement between the guidance and myself about the weekend of July 3-4, with many runs painting a far more gloomy & doomy scenario than I believe we are going to see. Call it a meteorological hunch, but the performance of said guidance about 5 and 6 days out for the weekend we just had was less than stellar, with models foretelling of a front moving in with showers and thunderstorms, when in reality we saw the build-in of summer heat and humidity with no such shower & storm activity. This time, I feel that Canadian high pressure is still being under-forecast by the guidance in general, and that we’ll see a stronger push from it resulting in a generally dry Saturday-Sunday period, coolest Saturday with a northeasterly air flow, milder Sunday with more of variable wind evolving into a regional land breeze from the west as the high pressure area sinks to the south. Am I highly confident of this play-out? No, not yet. So please follow the updates through the week, because it’s entirely possible that the guidance can make my hunch look like a joke. Time will tell… Looking into early next week (July 5-7), expect the return of summer warmth and some humidity, along with the chance of a few showers and thunderstorms especially later in the period as a disturbance moves in.

DAYS 11-15 (JULY 8-12)

A “weaker” version of our current pattern tries to set-up with high pressure to the south, another high residing somewhere in eastern Canada, and a boundary between. It’s many days away but my general idea is that we’re on the warm/muggy side of the boundary through mid period and then the boundary moves into or even south of the region again by late in the period. Once again plenty of time to evaluate the weather during this time, as it’s often harder to pick out distinctive medium range patterns in summer than it is during the other seasons.

Sunday June 27 2021 Forecast (7:46AM)

DAYS 1-5 (JUNE 27 – JULY 1)

Heat continues to build in as we close out the weekend and we’ll peak our hot days Monday and Tuesday. As we get to mid week a frontal boundary will get into the region and increase the chance for showers and thunderstorms.

TODAY: Lots of clouds early to mid morning, then partly to mostly sunny. Fog patches South Coast early morning. Highs 85-92, cooler Cape Cod. Dew point middle to upper 60s. Wind WSW 5-15 MPH with gusts over 20 MPH.

TONIGHT: Partly cloudy. Fog patches in sheltered locations. Lows 66-73. Dew point middle to upper 60s. Wind SW diminishing to under 10 MPH.

MONDAY: Mostly sunny. Slight chance of isolated afternoon thunderstorms. Highs 88-95, cooler South Coast. Dew point upper 60s. Wind SW 5-15 MPH, higher gusts.

MONDAY NIGHT: Mostly clear. Lows 68-75. Dew point upper 60s. Wind SW up to 10 MPH.

TUESDAY: Mostly sunny. Highs 90-97, cooler Cape Cod. Dew point falling to lower 60s. Wind W 5-15 MPH, higher gusts.

TUESDAY NIGHT: Mostly clear. Lows 68-75. Dew point lower to middle 60s. Wind WSW 5-15 MPH.

WEDNESDAY: Partly sunny. Chance of afternoon showers and thunderstorms. Highs 86-93. Dew point upper 60s. Wind SW 5-15 MPH.

WEDNESDAY NIGHT: Partly cloudy. Chance of evening showers. Patchy fog. Lows 67-74. Dew point upper 60s. Wind variable up to 10 MPH.

THURSDAY: Partly sunny. Chance of showers and thunderstorms. Highs 84-91. Dew point upper to middle 60s. Wind variable 5-15 MPH.

DAYS 6-10 (JULY 2-6)

A frontal boundary should be in the region to start the period with a higher shower and thunderstorm threat and less heat but still somewhat high humidity, and then high pressure from eastern Canada may sneak down and dry the region out but keep it on the warm side for July 3-4, before that high slips to the south, it stays warm but turns more humid later in the period. The confidence on this scenario is not particularly high still.

DAYS 11-15 (JULY 7-11)

No significant changes to the medium range outlook of a typical summertime pattern with weak jet stream to the north and a regional pattern of moderate humidity, warm air, and limited shower and thunderstorm opportunities.

Saturday June 26 2021 Forecast (8:53AM)

DAYS 1-5 (JUNE 26-30)

Classic summertime in New England pattern over the next five days….. During the weekend we climb the ladder into the heat and humidity. Saturday starts out on the cloudy side with both low level moisture producing low cloudiness and higher level moisture and warming air producing a lot of high cloudiness above that, but the limited or no sun start will progress to partial sun as the day goes on, though South Coast areas may never really break out into much if any sun at all during the day. Cloudiness of both high and low but especially the low variety dominates again tonight. When we get to Sunday, the ability to break those clouds up improves and the amount of high cloudiness coming across the sky from the west will also lessen. Net result: More sunshine Sunday than Saturday. Also, Sunday’s heat and humidity will be more noticeable than Saturday’s. Then it’s the full heat for Monday through Wednesday to finish off June. Monday will have only the minimal chance of isolated air mass showers or thunderstorms, and I think this even remote chance will be absent Tuesday with some potential drying of the air mass and a more westerly wind, not always well-forecast by guidance. Wednesday, a frontal boundary from the northwest that will be held back for several days finally tries to make a run into this area, and while it will likely fail in its effort to fully get into and across the region, in its weakening form it can still be a better trigger for showers and thunderstorms, so those will be in Wednesday’s forecast, with room for adjustment as we get closer to it…

TODAY: Mostly cloudy to partly sunny. Fog patches at times South Coast. Highs 77-82 South Coast, 83-88 elsewhere. Dew point middle to upper 60s. Wind SSW 10-20 MPH.

TONIGHT: Partly to mostly cloudy. Areas of fog South Coast. Lows 63-70. Dew point middle to upper 60s. Wind SW 5-15 MPH.

SUNDAY: Partly to mostly sunny. Fog patches South Coast early morning. Highs 85-92, cooler Cape Cod. Dew point middle to upper 60s. Wind WSW 5-15 MPH with gusts over 20 MPH.

SUNDAY NIGHT: Partly cloudy. Fog patches in sheltered locations. Lows 66-73. Dew point middle to upper 60s. Wind SW diminishing to under 10 MPH.

MONDAY: Mostly sunny. Slight chance of isolated afternoon thunderstorms. Highs 88-95, cooler South Coast. Dew point upper 60s. Wind SW 5-15 MPH, higher gusts.

MONDAY NIGHT: Mostly clear. Lows 68-75. Dew point upper 60s. Wind SW up to 10 MPH.

TUESDAY: Mostly sunny. Highs 90-97, cooler Cape Cod. Dew point falling to lower 60s. Wind W 5-15 MPH, higher gusts.

TUESDAY NIGHT: Mostly clear. Lows 68-75. Dew point lower to middle 60s. Wind WSW 5-15 MPH.

WEDNESDAY: Partly sunny. Chance of afternoon showers and thunderstorms. Highs 86-93. Dew point upper 60s. Wind SW 5-15 MPH.

DAYS 6-10 (JULY 1-5)

Using guidance loosely and applying anticipated model error for early July outlook. Frontal boundary that approaches the region on the final day of June washes out over the region July 1 & 2 with each day running the chance of a couple showers and thunderstorms forming in the region, hottest day July 1, not as hot July 2, humidity high to moderate levels. Stronger front pushes through early July 3 from a not-well-forecast stronger high from Canada which clears the region for the balance of the holiday weekend with lower humidity but still warm for the balance of July 3-4. Heat comes back a little bit July 5 as high pressure shifts to the south. Confidence is not high on this outlook.

DAYS 11-15 (JULY 6-10)

Still a low confidence forecast here too but overall idea is typical summertime pattern with weak jet stream to the north and a regional pattern of moderate humidity, warm air, and limited shower and thunderstorm opportunities.