DAYS 1-5 (MAY 24-28)

This may be one of the slowest onsets of a rain event I’ve observed. The eastern edge of the rain in a sharp edged form sat at the southwesterly edge of the WHW forecast area much of yesterday afternoon and evening, finally advancing somewhat to the east during the night, but continues to battle dry air in its attempt to reach the coast even after the day has dawned today. Here in Woburn MA, for example, I’ve had a few brief instances of a few drops of rain, but never enough to start wetting the ground, and as I watch the radar loop, you can see the echoes drying up as they move into the I-95 belt in my region. This battle will finally be won by the rain as we move through the morning and the rest of the day here, and eastern areas join already-wet western areas for a pretty wet and cool Sunday as low pressure south of our region sends its warm front slowly our way. This front will pass by tonight, at least partially, as the system will be occluding (low pressure passing by to our north) as its cold front starts to catch up with the warm front. The cold front will waste no time crossing our region during the first half of the day on Memorial Day, keeping shower chances in the picture until early afternoon when they end west to east. Outdoor parades / ceremonies marking the holiday will have to deal with at least scattered showers. A drying trend expands across the region along partial clearing later in the day, and we may set up for another nice sunset across parts of the region Monday evening. A warmer, drier westerly flow will be here Tuesday into Wednesday with a little more “summer preview” weather, but when we get to Wednesday, we need to watch for a shower or thunderstorm as a cold front drops down from the north. This is part of a pattern shift to a more amplified set up – evolving omega block with low pressure in the western US, high pressure in the central US, and low pressure near or just east of New England. You’ll notice this with the arrival of cooler air Wednesday night or Thursday. After a shower / t-storm threat Wednesday comes the chance of a pop-up instability shower on Thursday.

TODAY: Overcast. Periods of rain. Highs 52-59. Wind E to NE 5-15 MPH.

TONIGHT: Cloudy. Showers likely. Slight chance of a thunderstorm. Areas of drizzle. Patchy fog. Temperatures steady 52-59. Wind NE 5-15 MPH becoming variable to SW in some areas east of I-95.

MONDAY (MEMORIAL DAY): Mostly cloudy through early afternoon with a good chance of showers. Partial clearing later in the day. Highs 58-65 coast, 65-72 inland. Wind S to SW in some areas east of I-95, mainly N to NW elsewhere expanding across the region.

MONDAY NIGHT: Partly cloudy. Lows 44-51. Wind NW to W up to 10 MPH.

TUESDAY: Cloud / sun intervals. Highs 66-73 South Coast / Cape Cod, 74-81 elsewhere. Wind W to SW 5-15 MPH.

TUESDAY NIGHT: Mostly clear. Lows 53-60. Wind SW up to 10 MPH.

WEDNESDAY: Partly sunny. Afternoon and evening shower and thunderstorm chances north to south. Highs 68-75 South Coast, 76-83 elsewhere. Wind SW 5-15 MPH.

WEDNESDAY NIGHT: Partly cloudy. An evening shower possible south of I-90. Lows 50-57. Wind N 5-15 MPH.

THURSDAY: Partly sunny. A pop-up shower possible. Highs 63-70. Wind N 5-15 MPH.

DAYS 6-10 (MAY 29 – JUNE 2)

Indications are for upper level low pressure to sit just east of our region May 29 with additional shower potential and cool air in place, then pull far enough away for a diminished shower threat and milder weather for the May 30-31 weekend before high pressure builds in with fair weather to begin the month of June. This continues to be a low confidence outlook – check updates!

DAYS 11-15 (JUNE 3-7)

Indications are for cooler than average but also drier with limited shower chances during early June. This is due to a trough in place but axis far enough east so we’re drier over wetter, but this also prevents any sustained very warm to hot weather as well.

DAYS 1-5 (MAY 23-27)

Memorial Day Weekend features one dry day, one wet day, and one mixed but mostly rain-free day, in that order. High pressure to our northeast in Atlantic Canada holds back the moisture from an approaching low pressure area today, though its cloud canopy will cover the sky for the entirety of the day – although thin enough at times for some dimmed sunshine to make it through for a few hours, especially the further north and east you are in the region. Eventually the clouds will thicken up, but the rain will hold off until it makes a slow southwest-to-northeast advance tonight, particularly overnight. Sunday, the rain shield should be over most of the region by dawn, definitely shortly after if it hasn’t gotten all the way, and it may still be in a little bit of a battle with the dry air, but that dry air is overcome and we do have a pretty wet day in store, with a general 0.25 to 0.75 inch rainfall expected. By evening, the rain pattern will become more patchy although a few moderate to briefly heavy showers (maybe even the rumble of thunder) can occur. This can push a few rain totals closer to around 1 inch. Despite “bad timing”, any rainfall we do get will be beneficial as we need it to help reduce the ongoing abnormally dry / drought conditions in the region. Along with the rainfall, we’ll see temperatures confined to the 50s in most of the region on Sunday underneath a thick overcast with an onshore air flow. As low pressure departs to our east on Monday, Memorial Day, any lingering rain and drizzle exits first thing. We can see one more passing shower as a trough swings through between late morning and early afternoon from west to east, otherwise the general trend will be for some improvement as we move through afternoon, with breaks in the clouds and some partial clearing. As a result, Monday will be notably milder than Sunday. Tuesday will feature a drier and warmer westerly air flow with fair weather. The upper flow starts to become more amplified Wednesday which may start fair and warm then become cooler with a shower and thunderstorm threat, depending on the movement of a front and arrival of a low pressure disturbance.

TODAY: High overcast including some dimmed sun (especially north and east) thickens and lowers to a mid level overcast by late-day. Highs 58-63 coast, 64-69 inland. Wind variable to SE up to 10 MPH.

TONIGHT: Overcast. Rain arrives southwest to northeast. Lows 46-53. Wind E 5-15 MPH.

SUNDAY: Overcast. Periods of rain and drizzle. Areas of fog. Highs 52-59. Wind E to NE 5-15 MPH.

SUNDAY NIGHT: Cloudy. Showers likely. Slight chance of a thunderstorm. Areas of drizzle. Patchy fog. Temperatures steady 52-59. Wind NE 5-15 MPH.

MONDAY (MEMORIAL DAY): Mostly cloudy to partly sunny. Patchy drizzle and a brief shower possible early. An afternoon shower also possible. Highs 58-65 coast, 65-72 inland. Wind N to NW 5-15 MPH.

MONDAY NIGHT: Partly cloudy. Lows 44-51. Wind NW to W up to 10 MPH.

TUESDAY: Cloud / sun intervals. Highs 66-73 South Coast / Cape Cod, 74-81 elsewhere. Wind W to SW 5-15 MPH.

TUESDAY NIGHT: Mostly clear. Lows 53-60. Wind SW up to 10 MPH.

WEDNESDAY: Variably cloudy. Shower and thunderstorm chances increase during the day. Highs 70-77 but potentially cooler South Coast / Cape Cod. Wind SW 5-15 MPH may shift to N.

DAYS 6-10 (MAY 28 – JUNE 1)

Indications are for upper level low pressure to sit just east of our region May 28-29 with a cooling trend and shower chances, then pull far enough away for a diminished shower threat and milder weather for the May 30-31 weekend before high pressure builds in with fair weather to begin the month of June. There’s some uncertainty on the play-out of this scenario, so check daily updates!

DAYS 11-15 (JUNE 2-6)

Indications are for cooler than average but also drier with limited shower chances during early June. This is due to a trough in place but axis far enough east so we’re drier over wetter, but this also prevents any sustained very warm to hot weather as well.

DAYS 1-5 (MAY 22-26)

Heading into Memorial Day Weekend, we find ourselves in a somewhat familiar weather set-up here for this time of year. High pressure sits to our north, anchored in southeastern Canada with a drift eastward. A frontal boundary sits to our south and a wave of low pressure will be moving along it, approaching New England. The battle will be on between the dry air associated with the high pressure area and the moisture associated with the approaching / passing low. Today, the high is in control so we are dry with just filtered sunshine through a veil of high cloudiness (slightly thicker to the south but its edge often visible looking to the north). A light northeasterly air flow will keep the north-facing and east-facing coastal areas coolest today. Tonight, the clouds start to thicken, although they may remain thin enough for a little bit of sun to still be visible in northern and eastern portions of the WHW forecast area early Saturday. Otherwise, the slow turn of the battle in favor of the moisture means we’ll end up overcast. The dry air will be successful in holding off the low’s rain shield until at least Saturday evening in areas west and south of Boston, but eventually it gets in there and then spreads northeastward overnight into early Sunday. Some guidance keeps it dry into the first few hours of Sunday in eastern areas. I’m leaning toward the rain’s arrival by dawn throughout the region, however, making Sunday a pretty wet day. Rainfall amounts should be on the lighter side though, probably up to but mostly under a half inch before the steadiest rain tapers to occasional at night and then departs from west to east by dawn on Monday. Memorial Day itself should feature dominant cloud cover, although breaks of sun do become possible as the low pressure area moves away to the east and slightly drier air starts to work into the region in its wake. There can be a bit of drizzle or a leftover shower very early in the day, and we’ll have to watch for one more trough to swing through in the afternoon with the potential for a few more passing showers. Outdoor Memorial Day activities should take place under a mainly cloudy sky but without rain falling in most locations, although the ground likely to still be wet as most of these take place in the morning. Tuesday’s weather will be improved with dry conditions, though an upper trough over the region does promote a fair amount of cloud cover to limit sunshine that day as it looks this far in advance.

TODAY: Increasing high clouds. Highs 61-68, coolest coast. Wind N to NE up to 10 MPH.

TONIGHT: Thickening clouds. Lows 43-50. Wind calm.

SATURDAY: Cloudy. Highs 58-65, coolest coast. Wind SE up to 10 MPH.

SATURDAY NIGHT: Overcast. Rain arrives southwest to northeast. Lows 45-52. Wind E to NE 5-15 MPH.

SUNDAY: Overcast. Periods of rain and drizzle. Areas of fog. Highs 52-59. Wind E to NE 5-15 MPH.

SUNDAY NIGHT: Cloudy. Rain becomes intermittent. Areas of drizzle and fog. Lows 45-52. Wind NE to N up to 10 MPH.

MONDAY (MEMORIAL DAY): Mostly cloudy. Patchy drizzle and a brief shower possible early. An afternoon shower also possible. Highs 58-65. Wind N to NW 5-15 MPH.

MONDAY NIGHT: Partly cloudy. Lows 44-51. Wind NW up to 10 MPH.

TUESDAY: Cloud / sun intervals. Highs 61-68. Wind NW 5-15 MPH.

DAYS 6-10 (MAY 27-31)

Upper level low pressure and a couple passing surface disturbances bring shower and possible thunderstorm chances May 27 and 28, less of a chance May 29, along with cool conditions, before it departs to the east and is replaced by high pressure with fair and seasonable weather May 30-31 weekend.

DAYS 11-15 (JUNE 1-5)

Two disturbances bring passing shower chances during the first several days of June, with timing uncertain on them. For the most part it’s a dry and seasonable start to the first month of meteorological summer, based on current medium range indications.

DAYS 1-5 (MAY 21-25)

Cooler, drier air has arrived, but today it’s not with one of those bright blue sky days with fair weather clouds. Instead it will take place under a canopy of mid to high level cloud cover as a result of the frontal boundary staying just to our south while winds aloft are parallel to it (west to east) and a weak wave of low pressure moves by to our south this morning. This wave will bring some showers to eastern CT, RI, and southeastern MA, favoring the South Coast region, until about midday today before moving away. Still watching where the edge of the cloud canopy will be in regards to the potential for a nice sunset. Either way, enough thinning and clearing of the cloud deck takes place tonight for fairly optimal radiational cooling, leading to a pretty chilly (for late May) overnight and early morning on Friday. High pressure builds in with continued dry conditions and more sun Friday, though that will be more filtered with time through an increase in high cloudiness from the southwest as the day goes on. This cloud deck will start to thicken up Friday night into Saturday, but I remain fairly confident that the high pressure area, by then to our north and east, will have enough ability to keep our region dry much of Saturday’s daylight. Rain from an approaching low pressure wave should start to work in from southwest to northeast as early as the latter portion of the day but more likely holding off until sometime Saturday night, and this will lead to a fairly rainy and drizzly day on Sunday as the low makes its closest pass. I’m not expecting heavy rainfall, but enough to have to change outdoor plans that depend on dry weather. This middle day of the Memorial Day Weekend certainly looks the “worst”, as the holiday it self will start to show some improvement as low pressure departs to the east. How much clearing we see depends on how quickly any remaining low level moisture can be removed by a north to northwest air flow. But even with that, I still cannot rule out a passing shower. A little more refinement to this day’s forecast will come in the next few updates.

TODAY: Mostly cloudy. Morning showers possible South Coast. Highs 62-69. Wind NW 5-15 MPH.

TONIGHT: Clearing. Lows 38-45. Wind NW to N under 10 MPH.

FRIDAY: Increasing high clouds. Highs 61-68, coolest coast. Wind N to NE up to 10 MPH.

FRIDAY NIGHT: Thickening clouds. Lows 43-50. Wind calm.

SATURDAY: Cloudy. Rain potential increases south and west of Boston later in the day. Highs 58-65, coolest coast. Wind SE up to 10 MPH.

SATURDAY NIGHT / SUNDAY: Overcast. Periods of rain and drizzle. Areas of fog. Lows 45-52. Highs 52-59. Wind E to NE 5-15 MPH.

SUNDAY NIGHT: Cloudy. Lingering drizzle. Areas of fog. Chance of a shower. Lows 45-52. Wind NE to N up to 10 MPH.

MONDAY (MEMORIAL DAY): Mostly cloudy. A shower possible. Highs 58-65. Wind N to NW 5-15 MPH.

DAYS 6-10 (MAY 26-30)

An upper trough brings a shower chance each day May 26 & 27, but perhaps a better chance May 27 due to an accompanying surface disturbance / frontal system. Fair weather follows. Temperatures near to below normal.

DAYS 11-15 (MAY 31 – JUNE 4)

Watching for a couple relatively minor disturbances to bring passing shower chances in an otherwise mostly dry pattern with fairly seasonable though slightly variable temperatures.

DAYS 1-5 (MAY 20-24)

One more “summer preview” day today with very warm to hot air and moderate to high humidity in place until its pushed out by a cold front passing through the region. As this front moves through today, the atmosphere above is not as supportive for thunderstorms as it was yesterday, and the trigger point is further south, so I’m expecting the greatest chance for scattered activity to be from the I-90 belt southward this afternoon and evening, favoring the South Coast region the later it gets. It doesn’t mean we can’t see an isolated shower or storm to the north, but the chances are definitely lower up that way. The front will settle just to our south tonight into Thursday, and as a weak low pressure wave rides along it, a cloud canopy will remain in place, limiting Thursday’s sunshine quite a bit. In fact, some additional showers can move across the South Coast region, particularly during the morning hours. We may set up for a colorful sunset however, depending on the location of the edge of the cloud deck at the time the sun goes down. High pressure builds in with fair and seasonable weather for Friday. Will it hold into the weekend? The answer is: no. The high gives way to a slow return of the frontal boundary from the south, which allows clouds to increase on Saturday as low pressure gets set to track to our south. This process will be slow enough that despite losing the sunshine I do think we get through most of that day dry before rain arrives in the evening or at night from southwest to northeast, and continues during Sunday. Additional details about the full Memorial Day Weekend forecast will appear on tomorrow’s blog update.

TODAY: Variably cloudy. Shower and thunderstorm potential from late morning through afternoon, with highest thunderstorm potential I-90 belt southward. Highs 69-76 Cape Cod / Islands, 77-84 southeastern CT and southern RI to MA South Shore, 85-92 elsewhere. Wind SW increasing to 10-20 MPH, higher gusts possible, especially near any storms.

TONIGHT: Mostly cloudy. Lows 51-58. Wind NW 5-15 MPH.

THURSDAY: Mostly cloudy. Morning showers possible South Coast. Highs 62-69. Wind NW 5-15 MPH.

THURSDAY NIGHT: Clearing. Lows 43-50. Wind NW to N up to 10 MPH.

FRIDAY: Mostly sunny. Highs 62-69, coolest coast. Wind N to NE up to 10 MPH.

FRIDAY NIGHT: Clear followed by increasing high clouds. Lows 43-50. Wind calm.

SATURDAY: Thickening clouds. Rain potential increases south and west of Boston later in the day. Highs 58-65, coolest coast. Wind SE up to 10 MPH.

SATURDAY NIGHT / SUNDAY: Overcast. Periods of rain and drizzle. Areas of fog. Lows 45-52. Highs 52-59. Wind E to NE 5-15 MPH.

DAYS 6-10 (MAY 25-29)

Expecting low pressure to start pulling away by Memorial Day (May 25) with some partial improvement – less rain, some breaks in the clouds, but on the cool side. Upper level low pressure presents the chance of mainly afternoon showers both May 26 & 27, and a surface low and disturbance may enhance the chance on May 27. Fair weather returns later in the period. Temperatures continue to run on the cooler side through mid period but moderate to seasonable at the end of the period.

DAYS 11-15 (MAY 30 – JUNE 3)

Continued leaning toward a cool, dry pattern to end May and start June with eastern Canadian high pressure the most dominant feature.

DAYS 1-5 (MAY 19-23)

The back-door front that cooled eastern areas significantly yesterday has gone back to the northeast and opens the door for an early-season blast of summer heat today. While you’ll notice higher humidity with dew points generally 60+ across the region, a wind shift from southwest to west may drive them back down along the coastal plain this afternoon, but when this happens we often see a temperature spike, so some of the higher readings may also occur in these areas today. The other thing to eye is the potential for scattered to clustered thunderstorms erupting from the combination of daytime heating and an approaching trough. The best shot at this will be west of I-95 and they should be fading fairly quickly as they move eastward into the I-95 region and beyond by the end of the day. Where they are strongest, damaging wind gusts and hail are possible, but such occurrences should be isolated. Tonight is a quiet but very warm night. A cold front sweeps across the region Wednesday, its timing late enough so that it’s very warm (borderline hot) and somewhat humid, but early enough so that the shower and thunderstorm threat comes earlier and is focused more east of I-495 and from the I-90 belt southward. We need to watch closely because even one hour slower on the front would allow the chance of showers and storms to be further west and north initially. Once the front comes through the temp and dew point will reduce and Wednesday night won’t be nearly as “summer-feeling” as tonight will be. The front slows just off the South Coast and a quick-moving wave of low pressure can bring brief showers to the South Coast region early Thursday, otherwise look for a drier, cooler day with some lingering clouds then increasing sunshine. High pressure builds in Friday with fair weather, but departs as we get to the start of the weekend, at which time a wave of low pressure will approach from the southwest. This means increasing clouds for Saturday with eventually a rain chance, first to the west and south, then expanding north and east. Timing will be fine-tuned for the arrival of the wet weather as we get closer to the weekend.

TODAY: Mostly sunny to partly cloudy. Late-day shower and thunderstorm chances are highest west of I-95 into the I-95 belt. Highs 69-76 Islands / Cape Cod, 77-84 southeastern CT and southern RI to MA South Shore (southern portion), 85-92 elsewhere. Wind SW to W 5-15 MPH, higher gusts possible.

TONIGHT: Partly cloudy. Patchy fog. Lows 55-62. Wind W to SW up to 10 MPH.

WEDNESDAY: Variably cloudy. Shower and thunderstorm potential from late morning through afternoon, with highest thunderstorm potential I-95 belt southeastward. Highs 65-72 Cape Cod / Islands, 73-80 southeastern CT and southern RI to MA South Shore, 81-88 elsewhere. Wind SW increasing to 10-20 MPH, higher gusts possible, especially near any storms.

WEDNESDAY NIGHT: Clearing north, clouds linger south. Lows 48-55. Wind NW 5-15 MPH.

THURSDAY: Clouds and a shower chance South Coast early, otherwise increasing sun. Highs 63-70. Wind NW 5-15 MPH.

THURSDAY NIGHT: Partly cloudy. Lows 43-50. Wind NW to N up to 10 MPH.

FRIDAY: Mostly sunny. Highs 62-69. Wind N to NE up to 10 MPH.

FRIDAY NIGHT: Clear followed by increasing high clouds. Lows 43-50. Wind calm.

SATURDAY: Thickening clouds. Rain arrives southwest to northeast from midday through afternoon. Highs 58-65, coolest coast. Wind SE up to 10 MPH.

DAYS 6-10 (MAY 24-28)

The middle day of the Memorial Day Weekend (May 24) looks fairly wet as low pressure passes by to the south, followed by improvement but still a shower chance under upper level low pressure on Memorial Day. Upper low hangs around with a pop-up shower chance May 26 and/or May 27, then dry weather later in the period. Overall trend on temperatures is seasonable to slightly cooler than normal.

DAYS 11-15 (MAY 29 – JUNE 2)

Leaning cooler then average, drier overall, but not without at least a brief unsettled threat or two.

DAYS 1-5 (MAY 18-22)

A back-door cold front went through the region overnight and sets us up for a dry but cooler day today. The region overall will be a good 10 to 20 degrees lower than yesterday, which was quite a bit above normal, meaning that today will really not be that bad outside, just decidedly “less warm” than Sunday. Coolest readings will be along the east-facing and north-facing shores where wind is directly off the water. We’ll see some clouds scooting west to east across the sky, particularly in northern MA and southern NH, as warmer air is already returning aloft while the surface remains as described above. The much-talked-about summer preview arrives Tuesday with high pressure building to our south, driving warm to hot air and somewhat higher humidity into the region. While it won’t be oppressively humid, by definition, the fact that it’s early season moderate humidity will make it feel a bit worse in a relative sense, since we have not had a chance to adapt as we would by summer. An active breeze from the southwest will be a help, however, and this breeze coming off the Atlantic waters to the south will, of course, keep the South Coast / Cape Cod, and even to the southern portion of the MA South Shore less hot than the remainder of the region that has a pure land breeze. One thing to keep an eye out for later Tuesday is the potential for a few showers and thunderstorms in advance of a pre-frontal trough approaching from the northwest. The greatest chance to see these would be in northern MA and southern NH in the late afternoon to early evening hours. Most areas will remain dry, however, as coverage would be fairly limited. Any of those fade away or move out quickly and we’re left with a fair and very mild night, leading to the summery feeling continuing on Wednesday. The difference this day is that it will be cut off by an approaching and passing cold front, bringing more clouds and a better chance of showers and thunderstorms to the region. I still have to refine the expecting timing of this front in the next couple of updates, but for now I am leaning toward it being a quick enough passage that the greatest shower and thunderstorm chance may be from the I-95 belt southeastward. This will lead to fair and cooler weather Thursday and Friday as high pressure builds into the region.

TODAY: Mostly sunny to partly cloudy. Highs 62-69 coast, 70-77 inland. Wind shifting to NE 5-15 MPH.

TONIGHT: Partly cloudy. Lows 52-59. Wind variable up to 10 MPH becoming SW.

TUESDAY: Mostly sunny to partly cloudy. Slight chance of a late-day shower or thunderstorm favoring northern MA and southern NH. Highs 69-76 Islands / Cape Cod, 77-84 southeastern CT and southern RI to MA South Shore (southern portion), 85-92 elsewhere. Wind SW 5-15 MPH, higher gusts possible.

TUESDAY NIGHT: Partly cloudy. Patchy fog. Lows 55-62. Wind SW up to 10 MPH.

WEDNESDAY: Variably cloudy. Showers and thunderstorm potential from late morning through afternoon, with highest thunderstorm potential I-95 belt southeastward. Highs 65-72 Cape Cod / Islands, 73-80 southeastern CT and southern RI to MA South Shore, 81-88 elsewhere. Wind SW increasing to 10-20 MPH, higher gusts possible, especially near any storms.

WEDNESDAY NIGHT: Clearing. Lows 48-55. Wind NW 5-15 MPH.

THURSDAY: Partly cloudy. Highs 63-70. Wind NW 5-15 MPH.

THURSDAY NIGHT: Partly cloudy. Lows 43-50. Wind NW to N up to 10 MPH.

FRIDAY: Partly sunny. Highs 62-69. Wind N to NE up to 10 MPH.

DAYS 6-10 (MAY 23-27)

Memorial Day Weekend (May 23-25) looks cooler with high pressure to the north. Watching low pressure to the south and for now I continues to lean toward the greatest potential for wet weather to be later Saturday into Sunday with improvement for Memorial Day. Still a high degree of uncertainty on this outlook, so follow updates! An upper low hangs around with cooler weather and a few pop up showers possible into the middle of next week.

DAYS 11-15 (MAY 28 – JUNE 1)

Leaning cooler then average, drier overall, but not without at least a brief unsettled threat or two.

DAYS 1-5 (MAY 17-21)

A disturbance brought a round of showers through the region overnight – a nice drink for the flowers even through we still suffer a longer-term dry spell. It’s back to fair weather for the day today, some patchy clouds drifting across the sky but plenty of sun, and a little bit warmer in most areas than yesterday. Tonight, a back-door cold front swings into the region from the northeast, and while it’s not going to bring much in the way of clouds and certainly no rain, it will turn the region a little cooler for Monday, especially in eastern coastal locations which will have a wind off the water. But this front is pushed back the other way by Tuesday as the little bubble of high pressure from Canada that sent it down merges with the high pressure area off the East Coast to our south. This will pump in the warmth of summer for Tuesday and into Wednesday as well. Some areas can see their first 90 degree readings of the season on Tuesday for high temps, but I do not think this will be widespread, and it will most certainly be cooler along the South Coast and across Cape Cod and the Islands those days as a southwest wind comes across cooler ocean water before reaching those areas. We have to watch for shower and thunderstorm chances on Tuesday with the approach of a pre-frontal trough from the west. The most likely area to see anything would be central MA and southern NH later in the day or in the evening. I do think coverage on this will be low as far as the region goes, but I’ll keep an eye on it. A cold front will move across the region during Wednesday, providing a better chance of showers and storms. It’s still a few days away and timing is not nailed down, but I am leaning later in the day for it – northwest to southeast across the region. Behind this front, high pressure builds in with fair and more seasonable weather for Thursday.

TODAY: Mostly sunny to partly cloudy. Highs 68-75 South Coast, 76-83 elsewhere. Wind SW 5-15 MPH.

TONIGHT: Mostly clear. Lows 50-57. Wind SW 5-15 MPH.

MONDAY: Sunny to partly cloudy. Highs 62-69 coast, 70-77 inland. Wind shifting to NE 5-15 MPH.

MONDAY NIGHT: Partly cloudy. Lows 52-59. Wind variable up to 10 MPH becoming SW.

TUESDAY: Mostly sunny to partly cloudy. Slight chance of a late-day shower or thunderstorm favoring central MA and southern NH. Highs 68-75 Islands / Cape Cod, 76-83 southeastern CT and southern RI to MA South Shore, 84-91 elsewhere. Wind SW 5-15 MPH.

TUESDAY NIGHT: Partly cloudy. Patchy fog. Lows 55-62. Wind SW up to 10 MPH.

WEDNESDAY: Partly sunny. Afternoon and evening shower and thunderstorm chances. Highs 65-72 Cape Cod / Islands, 73-80 southeastern CT and southern RI to MA South Shore, 81-88 elsewhere. Wind SW increasing to 10-20 MPH.

WEDNESDAY NIGHT: Clearing. Lows 53-60. Wind NW 5-15 MPH.

THURSDAY: Mostly sunny. Highs 67-74. Wind NW 5-15 MPH.,

DAYS 6-10 (MAY 22-26)

This period contains the Memorial Day Weekend (May 23-25). Over the last few days I’ve been keeping an eye on the medium range models to see how they handle the potential for low pressure passing near or south of the region at some point during that period of time. Obviously beyond day 6 we still have quite a bit of uncertainty in the outlook, but today I lean toward the greatest wet weather threat taking place mid weekend (May 24) with fair weather both to start (May 22-23) and end (May 25-26) this time period. Temperatures, while somewhat typically variable, should average generally around normal for the period. Day to day variation can be made more clear as we get closer to these days.

DAYS 11-15 (MAY 27-31)

The outlook for the last 5 days of May, if based on guidance available, is rather uncertain, which is not unusual for heading out 2 weeks into the future in spring – and yes, late May is still spring, not summer. Guidance ranges from progression to blocking. Climatology says never count blocking out, even then. When I see range across guidance or wild inconsistency within any model that is considered reasonably accurate much of the time, I go with a vague outlook based on what I feel may be the most likely overall regime, and right now that is drier over wetter, cooler over warmer. Best bet: follow my daily updates.

DAYS 1-5 (MAY 16-20)

A very nice mid May weekend is here and while much of the forecast area missed out on beneficial rain from our last visit by low pressure, you now get the chance to enjoy very nice weather, courtesy of a high pressure area moving off the Mid Atlantic Coast. This will bring dry and warmer weather to us this weekend. If you were up early this morning, it was most definitely on the cool side and some areas started the day with fog patches from yesterday’s moisture condensing in a temp / dewpoint matched layer of air near the ground, but that quickly dissipates as the sun rises and the temp quickly climbs up and away from the dew point. The only interruption, if you will, comes in the form of a band of clouds and possibly a couple passing showers tonight as a quick-moving trough swings through the region from northwest to southeast, but this is gone other than a few clouds lingering in eastern and southern areas at dawn on Sunday, and we’re back to fair weather for the day. Monday also holds fair weather for us, but in classic New England fashion, a bubble of high pressure passing to our north will send a back-door front through the region with a temporary Atlantic breeze cooling it down for that day. This Canadian high will then join its southern cousin to our south by Tuesday and Wednesday when we see a preview of summer warmth. We will have to watch for shower and thunderstorm chances both days though. Tuesday, it’s from a trough approaching from the northwest that triggers them well north and west of our area but sends them in our direction. Right now I do believe most of them (if not all of them) don’t survive the trip, but since these can sometimes accelerate and create their own life support, so to speak, I can’t rule a couple out of making it into at least the northwestern reaches of the WHW forecast area later Tuesday. The better chance of showers and storms comes Wednesday as a cold front crosses the region. Currently, timing on this looks late day or evening, but at day 5 there is some uncertainty with that detail.

TODAY: Lingering stratus / fog patches dissipate by mid morning, otherwise sunshine and a few high clouds. Highs 63-70 South Coast, 71-78 elsewhere. Wind W to SW 5-15 MPH.

TONIGHT: Partly cloudy. Slight chance of a passing shower. Lows 51-58. Wind SW 5-15 MPH.

SUNDAY: Partly cloudy to mostly sunny. Highs 68-75 South Coast, 76-83 elsewhere. Wind SW 5-15 MPH.

SUNDAY NIGHT: Mostly clear. Lows 50-57. Wind SW 5-15 MPH.

MONDAY: Sunny to partly cloudy. Highs 62-69 coast, 70-77 inland. Wind shifting to NE 5-15 MPH.

MONDAY NIGHT: Partly cloudy. Lows 52-59. Wind variable up to 10 MPH.

TUESDAY: Mostly sunny to partly cloudy. Slight chance of a late-day shower or thunderstorm favoring central MA and southern NH. Highs 75-82 South Coast, 83-90 elsewhere. Wind SW 5-15 MPH.

TUESDAY NIGHT: Partly cloudy. Patchy fog. Lows 55-62. Wind SW up to 10 MPH.

WEDNESDAY: Partly sunny. Afternoon and evening shower and thunderstorm chance. Highs 73-80 South Coast, 81-88 elsewhere. Wind SW increasing to 10-20 MPH.

DAYS 6-10 (MAY 21-25)

Fair weather with temperatures returning to more seasonable levels May 21-22. May 23-25 is Memorial Day Weekend and I am watching for the potential for a wave of low pressure to bring a period of wet weather, not for the entire weekend, but somewhere around the middle to latter portion of it. This is far from a certainty, just something to keep in mind for now if you have outdoor plans for any of those days.

DAYS 11-15 (MAY 26-30)

A couple shower chances and alternating mild and cooler days in a variable, more progressive pattern.

DAYS 1-5 (MAY 15-19)

Upper level low pressure spins over the region today as surface low pressure slowly departs to our east. Other than a lingering patch of drizzle or a few showers in the region, today will end up drier than yesterday, though a bit cooler. Big changes loom for the weekend, but if you want fair and warmer weather it’s good news, because that’s exactly what we see as the wind flow turns west to southwest in response to high pressure building off the Mid Atlantic Coast. A back-door cold front driven by an eastern Canadian high pressure area will cool it down briefly on Monday, before the high to the south regains control and introduces the feel of summer by Tuesday.

TODAY: Lots of clouds. Patchy drizzle and the chance of a shower. Highs 55-62. Wind E shifting to N 5-15 MPH.

TONIGHT: Gradual clearing. Lows 45-52. Wind N shifting to W up to 10 MPH.

SATURDAY: Sunny to partly cloudy. Highs 63-70 South Coast, 71-78 elsewhere. Wind W to SW 5-15 MPH.

SATURDAY NIGHT: Partly cloudy. Lows 48-55. Wind SW 5-15 MPH.

SUNDAY: Partly cloudy to mostly sunny. Highs 68-75 South Coast, 76-83 elsewhere. Wind SW 5-15 MPH.

SUNDAY NIGHT: Mostly clear. Lows 50-57. Wind SW 5-15 MPH.

MONDAY: Sunny to partly cloudy. Highs 62-69 coast, 70-77 inland. Wind shifting to NE 5-15 MPH.

MONDAY NIGHT: Partly cloudy. Lows 52-59. Wind variable up to 10 MPH.

TUESDAY: Mostly sunny. Highs 75-82 South Coast, 83-90 elsewhere. Wind SW 5-15 MPH.

DAYS 6-10 (MAY 20-24)

Summer feel May 20 but with a shower and thunderstorm chance as a cold front approaches the area. Behind this front comes fair, more seasonable weather later next week. Early to mid portion of the Memorial Day Weekend shows fair weather followed by a shower chance as a disturbance arrives, but details on that are TBD.

DAYS 11-15 (MAY 25-29)

Overall pattern leans dry over wet, cool over warm, but some late-spring uncertainty is present. Watch updates for late month in the days ahead.

DAYS 1-5 (MAY 14-18)

An upper low will bring us unsettled weather including some beneficial rainfall today into Friday before it shifts eastward and departs in time for a fair and warmer weekend. Will it last into early next week? No (and yes). Stay with me here and I’ll explain it. First the upper low will be helping a surface low passing to our north to redevelop to our south, which then gets caught under its upper level support and does a loop just to our east and south tonight and early Friday. This helps prolong the rainfall, but the heaviest may be confined to a fairly narrow area somewhere northeast of Boston with another heavier band over the higher elevations of southwestern NH and central MA. We’ll have to radar-watch today / tonight to see how this plays out. An east to northeast flow on Friday will make that a cooler day than today as rain tapers to drizzle, with a clearing trend beginning at night as the low pulls away to the east. An area of high pressure building across the Mid Atlantic then sliding off the coast south to southeast of New England will promote drier, warmer weather with a west to southwest air flow over the weekend. After a cool start Saturday, we’ll undergo a notable warm-up. Sunday ends up the warmest of the two days with a higher temperature launching pad in the morning and continued warm advection. You knew this next part was coming, I bet. If not, it’s time to learn about it. Monday’s weather would probably be similar, but a high pressure area in eastern Canada is destined to send a back-door cold front into at least northeastern and eastern portions of the WHW forecast area, and perhaps a strong enough push to move it all the way through the region. This makes Monday a decidedly cooler day, especially in eastern coastal locations, although it does look like it will continue to be fair with plenty of sunshine as the high to the north will supply enough dry air.

TODAY: Mostly cloudy. Scattered to numerous showers. Highs 56-63. Wind S shifting to E 5-15 MPH.

TONIGHT: Cloudy. Widespread showers. Slight chance of thunderstorms. Lows 47-54. Wind E 5-15 MPH.

FRIDAY: Cloudy. Showers gradually diminish and drizzle lingers. Highs 55-62. Wind E shifting to N 5-15 MPH.

FRIDAY NIGHT: Gradual clearing. Lows 45-52. Wind N shifting to W up to 10 MPH.

SATURDAY: Sunny to partly cloudy. Highs 65-72 South Coast, 72-79 elsewhere. Wind W to SW 5-15 MPH.

SATURDAY NIGHT: Partly cloudy. Lows 48-55. Wind SW 5-15 MPH.

SUNDAY: Partly cloudy to mostly sunny. Highs 68-75 South Coast, 75-82 elsewhere. Wind SW 5-15 MPH.

SUNDAY NIGHT: Mostly clear. Lows 50-57. Wind SW 5-15 MPH.

MONDAY: Sunny to partly cloudy. Highs 62-69 coast, 70-77 inland. Wind shifting to NE 5-15 MPH.

DAYS 6-10 (MAY 19-23)

Warmer weather is back May 19 & 20 but watching for a possible disturbance to trigger a late-day thunderstorm chance on May 19 and a cold front to sweep through with a shower or thunderstorm possible on May 20. Fair, slightly cooler weather follows into later next week. May be watching low pressure to the south by the very end of the period for a potential rain threat, but not sure just yet.

DAYS 11-15 (MAY 24-28)

Watching the potential for low pressure passing to our south around the middle of the Memorial Day Weekend (May 24). Whether or not it’s close enough for a wet weather interruption remains to be seen and will be monitored. Fair weather much of this period otherwise with variable temperatures.

DAYS 1-5 (MAY 13-17)

We enter an unsettled weather period today which lasts into Friday as upper level low pressure drifts across our region. A related surface low in the Great Lakes sends its warm front our way today with brief rain possible and a wind shift to south. Before its cold front can cross the region on Thursday, the low redevelops to our south, becoming the main storm system while the initial storm system to the north weakens and dissipates. This low will then spin in the waters south to east of New England later Thursday into Friday before moving away. This evolution provides shifting winds and widespread rainfall for us. As the new surface low evolves our wind will shift from southerly to easterly from Wednesday to Thursday, then to northerly on Friday as the system begins to pull away. The weekend features a different pattern. Low pressure is gone and we find a west to southwest air flow transporting much warmer air into the region along with fair weather as an area of high pressure builds off the Mid Atlantic Coast.

TODAY: Mostly cloudy. Brief light rain period possible mid morning to midday, favoring areas from Boston west and north. Highs 56-63, coolest coast. Wind variable to E up to 10 MPH shifting to S 5-15 MPH with higher gusts by late-day.

TONIGHT: Mostly cloudy. Lows 49-56. Wind S 5-15 MPH, gusts over 20 MPH.

THURSDAY: Mostly cloudy. Scattered to numerous showers. Highs 56-63. Wind S shifting to E 5-15 MPH.

THURSDAY NIGHT: Cloudy. Numerous to scattered showers. Lows 47-54. Wind E 5-15 MPH.

FRIDAY: Mostly cloudy. Scattered to isolated showers. Highs 55-62. Wind E shifting to N 5-15 MPH.

FRIDAY NIGHT: Variably cloudy. Lows 45-52. Wind N shifting to W up to 10 MPH.

SATURDAY: Partly cloudy. Highs 65-72 South Coast, 72-79 elsewhere. Wind W to SW 5-15 MPH.

SATURDAY NIGHT: Partly cloudy. Lows 48-55. Wind SW 5-15 MPH.

SUNDAY: Partly cloudy. Highs 68-75 South Coast, 75-82 elsewhere. Wind SW 5-15 MPH.

DAYS 6-10 (MAY 18-22)

Back-door cold front potential May 18 with fair but cooler weather, especially eastern coastal locations. Fair, warm weather May 19 into May 20 before a cold front brings a shower / t-storm chance later May 20, followed by a slightly cooler air mass with dry weather later next week.

DAYS 11-15 (MAY 23-27)

Watching the potential for low pressure passing to our south around the middle of the Memorial Day Weekend. Whether or not it’s close enough for a wet weather interruption remains to be seen and will be monitored. Fair weather much of this period otherwise with variable temperatures.

DAYS 1-5 (MAY 12-16)

A disturbance that passed by our region overnight is moving offshore this morning with just some patchy clouds in eastern areas and a couple of light showers clipping the outer portion of Cape Cod before 8 a.m. After this, high pressure dominates and today turns out to be quite a nice day for mid May with sunshine, eventually sharing the sky with diurnal clouds as the sun-heated ground sends moisture into the sky that condenses in colder air aloft. These clouds will dissipate this evening but while that happens we’ll see an increase in high clouds from the west ahead of warm front from low pressure moving into the Great Lakes. Clouds thicken into Wednesday morning and as that front moves through, a period of light rain is possible. After the warm front goes by, while clouds remain abundant, it should be generally rain-free outside of a shower chance in central MA and southwestern NH later in the day, ahead of a cold front. As this front enters our region at night, the shower chance increases, but the front does not make a clean pass through. The upper level low that is driving the system is going to be drifting east southeast instead of traveling with its companion surface low into southeastern Canada, the latter eventually dying and giving way to a new surface low to the south, which quickly is caught under the upper low, becoming quasi-stationary for about 24 hours (Thursday to early Friday). This is when our wettest weather will occur, along with a cool-down due to thick overcast and an air flow off the still-chilly Atlantic waters. Double good news though: 1) The low does bring some beneficial rainfall to aid in keeping the dry conditions and areas of moderate drought from worsening too much. 2) It moves eastward enough so that we start to see improvement later Friday and most certainly in time for the start of the weekend, although we will still be on its western periphery Saturday with a sun / cloud mix and an active breeze and at least a pretty cool start to that day.

TODAY: Patchy clouds NH and eastern MA until mid morning including a brief shower Outer Cape Cod. Abundant sun mid to late morning. A sun / cloud mix midday and afternoon. Highs 60-67. Wind NW to W 5-15 MPH.

TONIGHT: Partly to mostly cloudy. Lows 43-50. Wind variable up to 10 MPH.

WEDNESDAY: Mostly cloudy. Chance of rain favoring areas north and west of Boston morning to midday. Highs 55-62 occurring by midday then may turn cooler especially coastal areas. Wind variable to E up to 10 MPH shifting to S 5-15 MPH.

WEDNESDAY NIGHT / THURSDAY: Mostly cloudy. Showers likely. Slight chance of a thunderstorm. Lows 48-55. Highs 55-62. Wind S shifting to E 5-15 MPH, higher gusts.

THURSDAY NIGHT: Cloudy. Widespread showers. Slight chance of a thunderstorm. Areas of fog forming. Lows 47-54. Wind E to NE 5-15 MPH.

FRIDAY: Cloudy with showers / drizzle through midday, then tapering off with breaks in the clouds later. Highs 55-62. Wind NE to N 5-15 MPH.

FRIDAY NIGHT: Variably cloudy. Lows 42-49. Wind N 5-15 MPH.

SATURDAY: Partly sunny. Highs 65-72 except cooler Cape Cod. Wind N to NW 5-15 MPH.

DAYS 6-10 (MAY 17-21)

High pressure dominates with fair, milder weather early to mid period. A brief shower chance around May 20 leads to slightly cooler but fair weather to end the period.

DAYS 11-15 (MAY 22-26)

This period encompasses from the Friday leading into Memorial Day Weekend to the Tuesday after it. Typically there is a lot of uncertainty in a medium range forecast in general, most especially spring time. Current trends indicate that this period of time features mostly dry weather and somewhat variable temperatures, with an increase in wet weather returning toward the end of the period.

DAYS 1-5 (MAY 11-15)

A cold front moving offshore holds a blanket of clouds over much of our region to start today out, including a ribbon of rainfall over Cape Cod, Martha’s Vineyard, and Nantucket, which will move out by about mid morning. A clearing trend will ensue and this afternoon will turn out pretty decent overall. High pressure builds in for tonight and Tuesday, but an upper level trough provides cold air aloft which will trigger diurnal cloud development to some extent this afternoon and more so on Tuesday, limiting the sun. Surface high pressure slides off the Mid Atlantic Coast by midweek as another upper low arrives from the west. The surface low associated with this system initially moves into the Great Lakes and will send its warm front in our direction Wednesday, which will feature a lot of cloud cover and the chance of some rainfall, though this may struggle to produce much with dry air in place initially. The upper level system will help redevelop low pressure to the south producing wetter weather on Thursday, as it stands now. This system will move far enough east on Friday that we break out of the heavy overcast but keep a lot of clouds and the chance of a shower around. Temperatures run near to below normal through this period.

TODAY: Cloudy start with rain ending Cape Cod / Islands. Clearing trend follows with increasing sunshine. Highs 59-66. Wind N to NW 5-15 MPH.

TONIGHT: Mostly clear. Lows 40-47. Wind NW 5-15 MPH.

TUESDAY: Sunny start, then a sun / cloud mix. Highs 58-65. Wind NW to W 5-15 MPH.

TUESDAY NIGHT: Partly to mostly cloudy. Lows 43-50. Wind variable up to 10 MPH.

WEDNESDAY: Mostly cloudy. Chance of rain. Highs 55-62 occurring by midday then may turn cooler especially coastal areas. Wind variable to E up to 10 MPH shifting to SE 5-15 MPH.

WEDNESDAY NIGHT / THURSDAY: Mostly cloudy. Showers likely. Lows 48-55. Highs 55-62. Wind SE to S 5-15 MPH, higher gusts.

THURSDAY NIGHT: Mostly cloudy. Lingering showers. Patchy fog. Lows 46-53. Wind variable to N up to 10 MPH.

FRIDAY: Variably cloudy. Chance of showers. Highs 58-65. Wind N to NW 5-15 MPH.

DAYS 6-10 (MAY 16-20)

May 16-17 weekend features dry weather and a warming trend as upper level low pressure departs to the east and high pressure builds in – cloud/sun mix and coolest Saturday, more sunshine and warmest Sunday. Milder pattern at least the early part of next week (May 18-20) but watching for a cold front and a shower / t-storm chance by the end of the period after fair weather to start. Too far in future for details.

DAYS 11-15 (MAY 21-25)

Pattern looks less blocked and more progressive with some up and down temps but overall milder to warmer with limited wet weather chances.

DAYS 1-5 (MAY 10-14)

Low pressure passing to our north will drag a cold front slowly across our area today and tonight. While there are a lot of clouds much of today, it will be generally rain-free until a broken band of showers, and perhaps a thunderstorm, is triggered by the front and moves across the region from west to east from mid afternoon to early evening. The front will slow down over southeastern areas while a wave of low pressure forms on it moving northeastward and passing just offshore overnight / early Monday morning. This will prolong shower chances from eastern CT and RI through southeastern MA during these hours. Monday’s daylight hours will see any showers exit Cape Cod first thing in the morning, with a general clearing trend from west to east. High pressure builds in later Monday through Tuesday with fair weather. The next low pressure system arrives from the west at midweek bringing back abundant cloud cover and a good chance of some wet weather later Wednesday and Thursday, with finer details to-be-determined.

TODAY: Considerable clouds / limited sunshine. A shower and slight chance of a thunderstorm west to east mid afternoon through early evening. Highs 58-65 South Coast, 65-72 elsewhere. Wind SW 5-15 MPH.

TONIGHT: Mostly cloudy. Chance of showers mainly eastern CT, RI and southeastern MA. Lows 48-55. Wind variable to N up to 10 MPH.

MONDAY: Any early showers exit Cape Cod with clouds thinning for sun west to east. Highs 60-67. Wind NW up to 10 MPH.

MONDAY NIGHT: Mostly clear. Lows 42-49. Wind NW 5-15 MPH.

TUESDAY: Sunny to partly cloudy. Highs 57-64. Wind NW 5-15 MPH.

TUESDAY NIGHT: Partly to mostly cloudy. Lows 43-50. Wind variable up to 10 MPH.

WEDNESDAY: Mostly cloudy. Chance of rain in the afternoon. Highs 55-62 occurring by midday then may turn cooler especially coastal areas. Wind variable to E up to 10 MPH.

WEDNESDAY NIGHT / THURSDAY: Cloudy. Chance of rain. Temperatures generally 50-57, coolest coast. Wind N 5-15 MPH.

DAYS 6-10 (MAY 15-19)

Upper level low pressure is expected to be over to just east of the region as part of a larger scale blocking pattern. Drier weather but not absent of shower chances. Temperatures start cool, then moderate later in the period.

DAYS 11-15 (MAY 20-24)

Upper level low pressure departs, replaced by a more west to east flow, up-and-down temperatures including milder to warmer air, and a few shower threats but overall a mostly dry pattern anticipated.