DAYS 1-5 (JUNE 5-9)

Surface high pressure to the south and an upper high pressure area overhead combine to give us another bright, very warm day today. Saturday’s conditions continue summery, but we see an increase in both cloud cover and humidity with the approach of an upper trough and surface front from the northwest. This surface and upper pair will progress through our region from Saturday night through Sunday night, bringing a period of unsettled weather, shifting wind, and eventually introducing a cooler air mass. The process looks a little different than was outline on yesterday’s update, mainly due to the front’s timing being slower and the surface wave traveling along it, originally expected to result in a cloudier, cooler Sunday, now tracking a little further north and holding the front back before pulling it through during the second half of Sunday. This allows for some sunshine for a number of hours on Sunday in a warmer air mass, allowing temperatures to be warmer than they’d have been in the previously-expected scenario. This changes the precipitation style from more widespread and stratiform to more convective and showery. I realize I just tossed a lot of info at you, so if you’re still wondering when the best chances of showers and possible thunderstorms are this weekend, here is your breakdown. The first shot comes Saturday afternoon, mainly north of I-90, but only isolated showers or thunderstorms would develop with a pre-frontal trough moving quickly through the region. The remains of a more solid line of showers and storms to the north and west makes a run at the region Saturday evening, with the most likely impact of any remaining activity taking place after sunset, with decreasing coverage from northwest to southeast. Another round of two of showers and possible thunderstorms could take place during Sunday, with odds favoring the afternoon and early evening hours based on current expected timing. Given the quick changes in the forecast for how this system acts as it goes through our region, I’d pay close attention to the next couple updates just to make sure it doesn’t have any other surprises in store for us this weekend. High pressure builds in with cooler, drier weather Monday, then sinks to the south with a warmer Tuesday following that, along with continued fair weather.

TODAY: Sun often filtered by high clouds. Highs 77-84 South Coast, 85-92 elsewhere but can turn cooler near the shoreline. Wind W to SW up to 10 MPH with coastal sea breeze possible.

TONIGHT: Mostly clear. Fog patches overnight. Lows 58-65. Wind SW up to 10 MPH.

SATURDAY: Partly sunny. An isolated shower or thunderstorm possible west and north of Boston after midday. Highs 86-93 except 78-85 South Coast. Dew point 65+. Wind SW 5-15 MPH, higher gusts.

SATURDAY NIGHT: Variably cloudy. Patchy fog. A shower or thunderstorm possible. Lows 62-69. Dew point 60+. Wind SW under 10 MPH but could be gusty near any showers / storms.

SUNDAY: Variably cloudy. A couple showers and thunderstorms probable, especially afternoon to early evening. Highs 76-83. Dew point 60+. Wind variable 5-15 MPH, can be stronger near any storms.

SUNDAY NIGHT: A shower potential early, followed by clearing. Fog patches form in lower elevations late evening then dissipate overnight. Lows 53-60. Dew point falls through 50s. Wind NW to N up to 10 MPH.

MONDAY: Mostly sunny. Highs 62-69. Wind N to NE 5-15 MPH.

MONDAY NIGHT: Clear. Patchy fog lower elevation locations. Lows 48-55. Wind calm.

TUESDAY: Mostly sunny. Highs 72-79. Wind W up to 10 MPH but potential for coastal sea breezes.

DAYS 6-10 (JUNE 10-14)

While there is an “attempt” at blocking of the omega-style in the upper pattern, it doesn’t have the organization or strength as the previous version. The orientation is further east as well. This allows high pressure to sink south of us with a quick warm-up by the middle of next week before a trough brings a shower & thunderstorm threat about June 11. Late week expectations are for high pressure to return with fair weather, briefly cooler then warming up again. Obviously, confidence in this scenario lowers with time, so catch updates.

DAYS 11-15 (JUNE 15-19)

Moving through mid month and into the final days of astronomical spring, the large scale pattern indications are for a weak high pressure ridge near or just west of our region to allow a trough or two to swing through. The latter would bring brief unsettled weather threats while the former would keep the overall pattern dry and seasonably mild to warm. I can’t rule out a cooler shot if one of the disturbances is stronger or high pressure to the north sends cooler air down from Atlantic Canada, and I’ll watch for both.

DAYS 1-5 (JUNE 4-8)

A flattening of the upper level flow due to a weakening of the blocking pattern that has been in place, along with surface high pressure to our south, allows for fair and much warmer weather today, Friday, and pretty much for the entire region during the daylight hours of Saturday as well. On Saturday, however, higher humidity combined with the approach of a frontal boundary from the northwest will open the door for the potential for an isolated shower or thunderstorm well west and/or north of Boston by late in the day. The shower threat becomes more likely by later Saturday night and especially Sunday as a cold front slowly crosses the region and we also get a trough moving through the region, inducing a weak wave of low pressure along the front. So Sunday’s profile is unsettled and turning cooler, making Saturday the easy weekend pick for outdoor activities. By Monday, the disturbance has exited and the frontal boundary is pulled offshore with cooler and drier air being delivered by high pressure in eastern Canada.

TODAY: Mostly sunny. Highs 75-82 South Coast, 83-90 elsewhere but can turn cooler near the shoreline. Wind W to SW up to 10 MPH with coastal sea breezes possible.

TONIGHT: Mostly clear. Lows 56-63. Wind variable to SW up to 10 MPH.

FRIDAY: Mostly sunny. Highs 77-84 South Coast, 85-92 elsewhere but can turn cooler near the shoreline. Wind W to SW up to 10 MPH with coastal sea breeze possible.

FRIDAY NIGHT: Mostly clear. Fog patches overnight. Lows 58-65. Wind SW up to 10 MPH.

SATURDAY: Partly cloudy. Slight chance of an isolated shower or thunderstorm well north and west of Boston by late-day. Highs 86-93 except 78-85 South Coast. Dew point 60+. Wind SW 5-15 MPH, higher gusts.

SATURDAY NIGHT: Mostly cloudy. An isolated shower or thunderstorm possible in the evening. Showers and patchy fog overnight. Lows 61-68. Dew point 60+. Wind variable up to 10 MPH.

SUNDAY: Mainly cloudy. Showers likely. Highs 71-78. Dew point 60+. Wind variable up to 10 MPH.

SUNDAY NIGHT: Mainly cloudy. Showers end. Patchy fog. Lows 52-59. Dew point falls through 50s. Wind N to NE up to 10 MPH.

MONDAY: Increasing sun. Highs 62-69. Wind NE 5-15 MPH.

DAYS 6-10 (JUNE 9-13)

Omega block configuration returns, but weaker than the previous version and also displaced further east, with our region between a further-offshore trough and a ridge in the Midwest and Great Lakes. This allows for a quicker warm-up heading into the middle of next week and only a minor unsettled weather threat later in the week as a weakening disturbance approaches the region from the west.

DAYS 11-15 (JUNE 14-18)

More shifting of the upper pattern as upper level low pressure sinks to the south off the Mid Atlantic Coast and high pressure shifts from the Great Lakes toward the Northeast while a trough settles into the Midwest / Plains. This pattern indicates near to above normal temperatures and slightly better shower and t-storm chances, but is still a fairly dry pattern overall for our region.

DAYS 1-5 (JUNE 3-7)

The overall idea going from the middle of this week through the first weekend of June is generally unchanged, as we have a relaxing of the omega blocking pattern enough to allow ridging to build in from the west aloft while low pressure shifts to the east, and a surface high becomes established to our south. An ocean storm that I had been previous a little suspicious of will stay far out at sea. This weather pattern means three days of fair weather and a warming trend through Friday, with some coastal modified temperatures based on wind direction. The weekend becomes a little more complicated as a frontal boundary approaches from the northwest on Saturday, increasing the humidity and eventually the chance for showers and thunderstorms, but as of this time I still feel the front’s approach will be slow enough that we get through that day without any showers and storms, and what remains of them to our north and west makes it into our region sometime at night. The frontal boundary is likely to be slowed by a wave of low pressure moving along it on Sunday, making that a much more unsettled weather day. Details on Sunday to-be-determined over the next few days as I monitor medium to short range guidance trends and the evolution of the set-up.

TODAY: Mostly sunny. Highs 70-77, coolest coast. Wind W up to 10 MPH but coastal sea breezes possible.

TONIGHT: Mostly clear. Lows 50-57. Wind variable up to 10 MPH.

THURSDAY: Mostly sunny. Highs 78-85 except 70-77 some coastal areas. Wind SW to SE up to 10 MPH.

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

FRIDAY: Mostly sunny. Highs 80-87 except 73-80 South Coast. Wind SW 5-15 MPH.

FRIDAY NIGHT: Mostly clear. Fog patches overnight. Lows 54-61. Wind SW up to 10 MPH.

SATURDAY: Partly cloudy. Highs 80-87 except 73-80 South Coast. Dew point climbs to 60+. Wind SW 5-15 MPH.

SATURDAY NIGHT: Variably cloudy. Showers and thunderstorms possible late evening and overnight. Fog patches. Dew point 60+. Lows 61-68. Wind SW to variable up to 10 MPH but can be gusty near any showers or storms.

SUNDAY: Mainly cloudy. Showers likely. Highs 71-78. Wind variable up to 10 MPH.

DAYS 6-10 (JUNE 8-12)

Omega block returns but not as defined as previously. Slow clearing June 8, fair weather into middle of next week. Unsettled weather chances increase later next week.

DAYS 11-15 (JUNE 13-17)

Omega configuration shifts to more a rex block set up as high pressure tries to build eastward from the Midwest but the trough nearer our area sinks to the south off the Mid Atlantic. This is a mostly dry pattern in general, but we do have to watch unsettled weather to the south in case it ends up further north than expected.

DAYS 1-5 (JUNE 2-6)

A pretty straightforward forecast for the next few days and then a little more complexity this weekend. Slight adjustment for today to lower then chance of a pop-up afternoon shower to isolated at best. At upper levels, while the general omega block pattern is still in place, the easternmost trough (the one over our region) tends to flatten and shift eastward over the next few days, and with surface high pressure building in and then sinking slowly to the south, we stay mainly dry (only the slight chance of that pop up shower with the lingering chilly air aloft today). We do also experience a general warming trend. It does appear that the offshore low pressure area I mentioned on yesterday’s discussion to watch for around Thursday will stay far enough out at sea to spare our region any impact. As is typical for late spring / early meteorological summer, any off-the-water wind, be it regional wind flow or local ocean breezes, will modify coastal temperatures at times, depending on orientation of land in relation to direction of wind. When we get to the weekend, we’ll have to watch a trough and frontal system to our northwest. Currently, my ongoing idea is that we stay rain-free, warm, and see a bit higher humidity Saturday with the trough and front still far enough to the northwest to not have any impact on our area.

TODAY: Mostly sunny to partly cloudy. Slight chance of isolated afternoon showers. Highs 67-74, coolest coast. Wind variable up to 10 MPH with coastal sea breezes.

TONIGHT: Partly cloudy to mostly clear. Lows 48-55. Wind variable up to 10 MPH.

WEDNESDAY: Mostly sunny. Highs 70-77, coolest coast. Wind W up to 10 MPH but coastal sea breezes possible.

WEDNESDAY NIGHT: Mostly clear. Lows 50-57. Wind variable up to 10 MPH.

THURSDAY: Mostly sunny. Highs 78-85 except 70-77 some coastal areas. Wind SW to SE up to 10 MPH.

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

FRIDAY: Mostly sunny. Highs 80-87 except 73-80 South Coast. Wind SW 5-15 MPH.

FRIDAY NIGHT: Mostly clear. Fog patches overnight. Lows 54-61. Wind SW up to 10 MPH.

SATURDAY: Partly cloudy. Highs 80-87 except 73-80 South Coast. Dew point climbs to 60+. Wind SW 5-15 MPH.

DAYS 6-10 (JUNE 7-11)

Omega block returns but not as defined as previous version. Trough and frontal system bring unsettled weather to our region June 7-8 followed by mainly dry weather with temperatures near to below normal.

DAYS 11-15 (JUNE 12-16)

The omega pattern tries to hang on, but shifts a bit east and varies from weak to moderate in strength. With the eastward shift, our region is more likely dry with only brief unsettled weather chances with passing disturbances / fronts. It’s a slightly warmer pattern overall.

DAYS 1-5 (JUNE 1-5)

The pattern to start June is the omega block I’ve been talking about, and the pattern that resulted in our unsettled weekend. The continuation of this pattern does not mean that every day this week is unsettled, however. A pair of disturbances, one exiting the region early today and another one crossing the region on Tuesday are what bring us a few shower and thunderstorm chances, but with limited coverage. Chances are best in southern areas early today and in isolated to scattered form anywhere in the region on Tuesday afternoon. At midweek, a surface high will keep it fairly quiet along with a warming trend, in general, which lasts into late week. The one potential fly in the ointment is an offshore low to the south on Thursday that may get close enough to turn the wind onshore across much of the region. If this does happen, then that day would be notably cooler, especially in coastal areas. I’ll keep an eye on that.

TODAY: Considerably cloudy with passing showers possible early to mid morning, then increasing sun, but still some clouds with a pop-up afternoon shower possible hilly terrain central MA and southwestern NH. Highs 59-66, coolest coastal areas. Wind NE 5-15 MPH.

TONIGHT: Partly cloudy to mostly clear. Lows 42-49. Wind variable under 10 MPH.

TUESDAY: Partly cloudy. Isolated afternoon showers and thunderstorms. Highs 67-74, coolest coast. Wind variable up to 10 MPH with coastal sea breezes.

TUESDAY NIGHT: Clearing. Lows 50-57. Wind variable up to 10 MPH.

WEDNESDAY: Mostly sunny. Highs 70-77, coolest coast. Wind W up to 10 MPH but coastal sea breezes possible.

WEDNESDAY NIGHT: Mostly clear. Lows 50-57. Wind variable up to 10 MPH.

THURSDAY: Partly sunny. Highs 63-70 coast, 71-78 inland. Wind SE 5-15 MPH.

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

FRIDAY: Mostly sunny. Highs 78-85 except 70-77 South Coast. Wind SW 5-15 MPH.

DAYS 6-10 (JUNE 6-10)

Large scale omega block continues but weakens with gradual de-amplification. We’re still in the mean trough position though which prevents hot weather and delivers some unsettled weather chances. Currently expecting a delayed arrival of a front until very late Saturday (June 6) or early Sunday (June 7) from the north, increasing the shower chances. This is followed by drier and cooler weather with Canadian high pressure’s influence, before unsettled weather chances return by the middle of next week.

DAYS 11-15 (JUNE 11-15)

Weak blocking transitions to zonal (west to east) pattern with seasonable but somewhat variable temperatures and a couple of passing shower and t-storm chances, timing to-be-determined.

DAYS 1-5 (MAY 31 – JUNE 4)

Today we wrap May up with a much less stormy day than we had yesterday, however we remain under upper level low pressure on the eastern side of an omega block configuration, and that leaves us vulnerable to additional unsettled weather. The next disturbance drops into this trough via eastern Canada later today and lingers into Monday, bringing us a couple additional rounds of showers, the first later this afternoon into this evening, and the second early Monday. We can still see pop-up showers from diurnal heating Monday and Tuesday afternoons, but those should be rather isolated. High pressure brings more sunshine without a shower chance Wednesday. By Thursday I still expect dry weather but we may see more cloudiness again from a combination of a disturbance to our north and west and another offshore to our south.

TODAY: Sun then quite a few clouds. Mid to late afternoon shower threat develops from north to south including a slight chance of thunderstorms. Highs 62-69. Wind NW 5-15 MPH.

TONIGHT: Variably cloudy with showers possible in the evening then partly cloudy overnight. Lows 50-57. Wind NW 5-15 MPH.

MONDAY: Partly sunny. Isolated showers. Highs 65-72. Wind NW 5-15 MPH.

MONDAY NIGHT: Partly cloudy. Lows 50-57. Wind NW 5-15 MPH.

TUESDAY: Partly cloudy. An isolated shower possible. Highs 66-73. Wind W 5-15 MPH.

TUESDAY NIGHT: Clearing. Lows 50-57. Wind W up to 10 MPH.

WEDNESDAY: Mostly sunny. Highs 67-74. Wind W up to 10 MPH but coastal sea breezes possible.

WEDNESDAY NIGHT: Mostly clear. Lows 50-57. Wind variable up to 10 MPH.

THURSDAY: Partly sunny. Highs 65-72, coolest coast. Wind variable up to 10 MPH with coastal sea breezes.

DAYS 6-10 (JUNE 5-9)

The omega blocking pattern starts to weaken gradually including de-amplifying for a more northwest to southeast flow. Watching a cold front that can bring a shower and thunderstorm chance on June 6 and some lingering cloudiness as the front may be slow to depart on June 7. That’s about the only bump in the road I can see right now in an otherwise fairly benign pattern that lacks a lot of rain as well as any sustained warmth.

DAYS 11-15 (JUNE 10-14)

Borderline block to zonal .. transition toward more zonal continues as far as I can tell, but quick reversal to temporary blocking again is not completely out of the question. Overall looking at limited rain chances and somewhat variable temperatures not straying too far from seasonal “typicals”.

DAYS 1-5 (MAY 30 – JUNE 3)

The well-advertised stormy Saturday is ongoing as a potent upper low and associated surface low pressure system move through our region. A little different than a more typical west-to-east or southwest-to-northeast storm track we see with many of our storm systems, this one, in response to the upper level flow on the eastern side of a large-scale omega block, has a south southeastward course, but because the surface low is interacting with its upper level partner, its own track includes a cyclonic loop. This somewhat anomalous and complex set-up was responsible for the different direction of delivery, so to speak. The system’s warm front moved through last evening from the northwest preceded by a period of rain in some areas. Last night (and still this morning to the south) we sit in the warm sector before the storm’s cold front whips in from the north and as the system rapidly matures (occludes), its southeastward movement will put us in a powerful back-lash which will have its greatest impact from southern NH through northern MA early on and shift to the south with time as the system progresses. It’s a rather small system in size, but what it lacks in size it makes up for in potency with a small area of heavy rainfall (this stays mostly to the north). Some of you may have been woken up by thunderstorms overnight but those moved out in time for some morning sunshine before a rapid deterioration in conditions. Strongest winds today will occur in higher elevations and along the coast, typical of what we might see in a winter storm. And speaking of winter, the anomalously cold air aloft with this system is causing some mountain snow to our north, and some of our highest elevations of southwestern NH will be close to or just cold enough to see some mixing of wet snowflakes with rain there if it comes down heavily enough – not unheard of in May, but quite rare in general, and even more so given we’re nearly at month’s end and under 48 hours from the start of June. Look for some downed tree limbs and in some cases whole trees as they are now leafed-out and more susceptible to strong wind gusts. This can lead to some power outages. Also, along the coast, splash-over can lead to areas of flooding especially late this morning to early this afternoon as some of the strongest winds coincide with high tide. All of this starts to settle down steadily from north to south later today and tonight as the low pressure system exits the region. We’re in for a “better” day on Sunday, but with the trough in place, and sunshine heating the land, and yet another disturbance dropping in from the north, we can see some shower and thunderstorm development by later in the day or during the evening. Most areas should get through most of the day without a rain threat, however. While the core of this disturbance goes by Sunday night, enough cold air aloft remains that we can see a few additional pop-up showers on Monday, to start the month of June (new month / same pattern). We still have enough chilly air above us to not be able to rule out a pop up shower on Tuesday. It will be Wednesday when I believe we can expect something in the way of full (or at least abundant) sunshine with high pressure in control.

TODAY: Early sun to the south followed by clouds and periods of rain while to the north overcast with drizzle and an area of heavier rainfall for a time favoring late morning to midday, heaviest northeastern MA and southeastern NH. Embedded thunder possible. Very slight chance of mixed rain and wet snow in highest elevations of southwestern NH. Temperatures fall to 38-45 northern MA and southern NH, coldest in higher elevations, and 46-53 elsewhere in the morning then recover to late-day highs 51-58 regionwide. Wind NE to N 15-25 MPH, gusts 35-55 MPH, strongest in coastal areas and higher elevations.

TONIGHT: Partly cloudy. Lows 46-53. Wind NW 5-15 MPH with higher gusts, diminishing overnight.

SUNDAY: Sun then quite a few clouds. Mid to late afternoon shower threat develops from north to south including a slight chance of thunderstorms. Highs 62-69. Wind NW 5-15 MPH.

SUNDAY NIGHT: Variably cloudy. Scattered showers. Lows 50-57. Wind NW 5-15 MPH.

MONDAY: Partly sunny. Isolated showers. Highs 65-72. Wind NW 5-15 MPH.

MONDAY NIGHT: Partly cloudy. Lows 50-57. Wind NW 5-15 MPH.

TUESDAY: Partly cloudy. An isolated shower possible. Highs 66-73. Wind W 5-15 MPH.

TUESDAY NIGHT: Clearing. Lows 50-57. Wind W up to 10 MPH.

WEDNESDAY: Mostly sunny. Highs 67-74. Wind W up to 10 MPH but coastal sea breezes possible.

DAYS 6-10 (JUNE 4-8)

Omega blocking pattern keeps our region under a trough of low pressure with a few shower chances and temperatures near to below normal.

DAYS 11-15 (JUNE 9-13)

Omega blocking pattern weakens slightly but remains in place with temperatures near to below normal and a couple unsettled weather chances.

DAYS 1-5 (MAY 29 – JUNE 2)

We now have an omega blocking pattern, classic for springtime, across the US, with our region sitting under the eastern member of dual low pressure troughs on either side of a high pressure ridge. This pattern has some staying power and will re responsible for cooler than average and unsettled weather. A vigorous upper low and associated surface low will drop south southeastward from Canada today into Saturday before departing mid weekend to bring us our first round of unsettled weather with variety. While this system is good for an accumulating snow threat in the mountains to our north, the closest it comes to “wintry” weather in the WHW forecast area is a potential mix of rain and wet snow in the Monadnock Region’s higher elevations Saturday morning. Before that, we get a shot of light rainfall ahead of the low’s arrival late today or this evening, a round of showers and possible thunderstorms tonight, then a back-lash of rain and drizzle as the surface system moves off to our southeast during Saturday – morning to early afternoon to the north and midday into evening further to the south. Some improvement is indicated for Sunday, but the next disturbance will drop out of Canada into the trough for additional shower and possible thunderstorm chances Sunday evening into Monday before we dry out somewhat but still retain the chance of a pop-up shower on Tuesday.

TODAY: Limited sun / lots of clouds. Rain chances increase north to south late-day. Highs 63-70. Wind NW 5-15 MPH with gusts 20-25 MPH.

TONIGHT: Mostly cloudy. Showers likely. Slight chance of a thunderstorm. Lows 40-47. Wind W 5-15 MPH with gusts 20-25 MPH, shifting to N.

SATURDAY: Mainly cloudy. Rainy periods southern NH an northern MA mostly morning to early afternoon (may mix with wet snow higher elevations of southwestern NH) and southern MA through eastern CT and RI midday to early evening. Temperatures fall to 36-43 northern MA and southern NH, coldest in higher elevations, and 44-51 elsewhere in the morning then recover to late-day highs 51-58 regionwide. Wind NE to N 15-25 MPH, gusts 35-55 MPH, strongest in coastal areas.

SATURDAY NIGHT: Partly cloudy. Lows 46-53. Wind NW 5-15 MPH with higher gusts, diminishing overnight.

SUNDAY: Partly sunny. A pop-up shower possible. Highs 62-69. Wind NW 5-15 MPH.

SUNDAY NIGHT / MONDAY: Variably cloudy. Chance of showers. Lows 50-57. Highs 63-70. Wind NW 5-15 MPH.

MONDAY NIGHT / TUESDAY: Partly cloudy. A shower possible. Lows 53-60. Highs 65-72. Wind NW to N 5-15 MPH.

DAYS 6-10 (JUNE 3-7)

Omega blocking pattern keeps our region under a trough of low pressure with a few shower chances and temperatures below normal.

DAYS 11-15 (JUNE 8-12)

Omega blocking pattern weakens slightly but remains in place with temperatures near to below normal and a few unsettled weather chances, though the pattern is not looking overly wet either.

DAYS 1-5 (MAY 28 – JUNE 1)

A cold front and secondary trough pushed through our region late yesterday and last night with isolated showers and a switch from a very warm to a more seasonable air mass. As we get into an upper trough on the eastern side of an omega block, we’ll see diurnal clouds pop up today and some of them will produce showers, along with a slight chance of a thunderstorm. Any of these showers or storms can grow enough to produce some small hail. This may also be a good day to look for rainbows if a shower is departing your area later in the day when the sun angle is lower. After a quiet but cool overnight and Friday morning, clouds move back in as a vigorous upper low and associated surface system dive south southeastward out of eastern Canada. This will bring us a period of unsettled weather later Friday and much of Saturday. Though it will not be overcast with rain the entirety of the time, clouds will dominate, and wet weather – a period of rain – is most likely Friday evening, followed by a couple rounds of showers during Saturday. A period of rain and drizzle is possible at some point Saturday on the back side of the surface low as it heads off the coast. This would most likely occur in southeastern NH and eastern MA. While some guidance leans toward this hold off until later Saturday, I currently favor an earlier timeline, but will watch short range guidance trends to try to pin down when the best chance of that would be. This system moves far enough offshore to drastically improve the weather for Sunday, but like today, with upper level low pressure in place, we see at least diurnal cloud development, and I cannot rule out a few pop-up showers for the final afternoon of May. The next disturbance drops into the upper trough position via eastern Canada on Monday to start June off with the chance of additional pop-up showers.

TODAY: Sun and patchy clouds early. Clouds more developed by midday with scattered showers and the chance of a thunderstorm including the possibility of small hail. Highs 65-72. Wind N 5-15 MPH except some coastal sea breezes.

TONIGHT: Partly cloudy. Lows 49-56. Wind NW 5-15 MPH.

FRIDAY: Limited sun / lots of clouds. Rain chances increase north to south late-day. Highs 62-69. Wind NW 5-15 MPH.

FRIDAY NIGHT: Mostly cloudy. Showers likely. Slight chance of a thunderstorm. Lows 51-58. Wind W 5-15 MPH.

SATURDAY: Mostly cloudy with periods of rain morning, especially southeastern NH and eastern MA. Variably cloudy with additional showers possible afternoon. Highs 58-65. Wind N 10-20 MPH with higher gusts.

SATURDAY NIGHT: Partly cloudy. Lows 46-53. Wind NW 5-15 MPH with higher gusts, diminishing overnight.

SUNDAY: Partly sunny. A pop-up shower possible. Highs 65-72. Wind NW 5-15 MPH.

SUNDAY NIGHT: Partly cloudy. Lows 50-57. Wind W up to 10 MPH.

MONDAY: Variably cloudy. Chance of afternoon showers. Highs 66-73. Wind W 5-15 MPH becoming variable.

DAYS 6-10 (JUNE 2-6)

Omega blocking pattern puts our region under a trough of low pressure with a few shower chances and temperatures below normal.

DAYS 11-15 (JUNE 7-11)

Omega blocking pattern weakens and flattens to a more zonal (west to east) flow with a couple shower chances and temperatures more seasonable, though somewhat variable.

DAYS 1-5 (MAY 27-31)

Another “summer preview” day today with above normal temperatures. We’ll see more cloudiness than yesterday and just the chance of a late-day shower or thunderstorm in a few places as a cold front drops down from the north. That front will put an end to the taste of summer, bringing cooler air back for the balance of the week which will bring us to the end of the month. With an upper trough passing through the region tomorrow, there can be a few diurnally driven instability showers, but most of us will stay dry. A vigorous upper low will move into our region from east central Canada later Friday into the weekend as part of the evolution of an omega blocking pattern. This will bring us a period of unsettled weather later Friday into the weekend, but don’t get the idea it’s going to rain for 2 1/2 days. It won’t be. The upper low and an associated surface system brings wet weather chances later Friday, particularly that night. The track of both the upper and surface features will help determine the details. I’m watching the possibility of some thunderstorms at least in parts of the region later Friday, a possible back lash of showers early Saturday, and some instability pop-up showers both Saturday and Sunday afternoons, but also leaving plenty of rain-free hours as we head through the weekend as well. More refining to come on next update!

TODAY: Partly sunny. Chance of a late-day shower or thunderstorm, favoring areas north of I-90. Highs 70-77 South Coast, 78-85 elsewhere. Wind SW 5-15 MPH.

TONIGHT: Partly cloudy. An evening shower possible south of I-90. Lows 52-59. Wind N 5-15 MPH.

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

THURSDAY NIGHT: Variably cloudy. A shower possible. Lows 51-58. Wind N 5-15 MPH shifting to W.

FRIDAY: Lots of clouds. Shower chances increase. Thunderstorms possible by late-day favoring areas south and west of Boston. Highs 61-68. Wind W to variable 5-15 MPH.

FRIDAY NIGHT: Cloudy. Showers likely. Chance of a thunderstorm. Lows 50-57. Wind variable 5-15 MPH.

SATURDAY: Mostly cloudy with morning showers. Partly cloudy afternoon with a shower possible. Highs 62-69. Wind variable to N 5-15 MPH.

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

SUNDAY: Partly sunny. A pop-up shower possible. Highs 65-72. Wind NW 5-15 MPH.

DAYS 6-10 (JUNE 1-5)

Omega blocking pattern puts our region under a trough of low pressure with a few shower chances and temperatures below normal. Day to day details TBD.

DAYS 11-15 (JUNE 6-10)

Indications are for near to below normal temperatures and limited shower chances as the omega block slowly weakens and we start a transition toward a more zonal (west to east) flow pattern.

DAYS 1-5 (MAY 26-30)

Like last week, it’s Tuesday and Wednesday that win the warm award for the week – another summer preview as we get closer to the start of the meteorological version of the season. High pressure to our south pumps warmer air into the region today into Wednesday before a cold front cuts that off later Wednesday. The front will have limited moisture to work with so widespread showers and storms are not likely – just isolated to scattered activity late Wednesday, otherwise it’s dry weather for these two days. Thursday’s weather is cooler and there can be a pop up shower with an upper low in the vicinity. A stronger upper low and associated surface disturbance will drop southeastward out of Canada in the eastern trough position of an evolving omega block (high pressure middle of US, low pressure western US). This feature will bring us some wet weather later Friday into early Saturday, based on current timing. Details of this system still have to be worked out and will be done so over the next few blog updates!

TODAY: Mostly sunny. Highs 67-74 South Coast / Cape Cod, 75-82 elsewhere. Wind W to SW 5-15 MPH.

TONIGHT: Partly cloudy. Patchy fog low elevations. Lows 54-61. Wind SW up to 10 MPH.

WEDNESDAY: Partly sunny. Chance of a late-day shower or thunderstorm, favoring areas north of I-90. Highs 70-77 South Coast, 78-85 elsewhere. Wind SW 5-15 MPH.

WEDNESDAY NIGHT: Partly cloudy. An evening shower possible south of I-90. Lows 52-59. Wind N 5-15 MPH.

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

THURSDAY NIGHT: Variably cloudy. A shower possible. Lows 51-58. Wind N 5-15 MPH.

FRIDAY: Lots of clouds. Shower chances increase. Highs 61-68. Wind N 5-15 MPH.

FRIDAY NIGHT: Cloudy. Showers likely. Chance of a thunderstorm. Lows 50-57. Wind variable 5-15 MPH.

SATURDAY: Mostly cloudy with morning showers. Partly cloudy afternoon. Highs 62-69. Wind variable to N 5-15 MPH.

DAYS 6-10 (MAY 31 – JUNE 4)

Upper low shifts east far enough for a mostly fair weather finish to May but still close enough that a pop-up shower or t-storm cannot be completely ruled out. General pattern to start June keeps New England under the eastern upper low member of an omega block. Pattern is on the cooler side of average with a couple shower chances.

DAYS 11-15 (JUNE 5-9)

Indications are for cooler than average but also mostly dry with limited shower chances during this period as the omega block gradually weakens.

DAYS 1-5 (MAY 25-29)

On this Memorial Day, as we always do, we remember those who paid the ultimate sacrifice for us. Many cities and towns have outdoor parades and services to do this, including my own, and many of those take place in the morning to midday hours. This year, it coincides with fog, and a band of rainfall that has to move through the region from west to east this morning and midday, so if you are involved in being in one such event or attending it, be as ready as you can for that rainfall. This is taking place as a final trough moves through as low pressure departs offshore. Improving weather follows this afternoon and we’ll see a clearing trend from west to east, and the day turns out quite a bit milder than yesterday was. High pressure builds in with fair, warmer weather Tuesday, and this lasts into Wednesday as the high sinks to our south. But a cold front dropping down from the north may bring a shower or thunderstorm later Wednesday, and most definitely brings back cooler weather for Thursday. An upper low and developing surface low to our east threatens another shower later Thursday and rather unsettled weather by Friday, when it will turn even cooler – quite the contrast from just two days prior. Spring in New England!

TODAY: Overcast with areas of fog and an area of rain moving through from west to east into midday. Clearing trend west to east this afternoon. Highs 60-67 Cape Cod, 68-75 elsewhere, occurring late-day. Wind variable up to 10 MPH, eventually NW increasing to 5-15 MPH.

TONIGHT: Mostly clear. Lows 48-56. Wind NW to W up to 10 MPH.

TUESDAY: Mostly sunny. Highs 67-74 South Coast / Cape Cod, 75-82 elsewhere. Wind W to SW 5-15 MPH.

TUESDAY NIGHT: Partly cloudy. Patchy fog low elevations. Lows 54-61. Wind SW up to 10 MPH.

WEDNESDAY: Partly sunny. Chance of a late-day shower or thunderstorm, favoring areas north of I-90. Highs 70-77 South Coast, 78-85 elsewhere. Wind SW 5-15 MPH.

WEDNESDAY NIGHT: Partly cloudy. An evening shower possible south of I-90. Lows 52-59. Wind N 5-15 MPH.

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

THURSDAY NIGHT: Variably cloudy. A shower possible. Lows 51-58. Wind N 5-15 MPH.

FRIDAY: Lots of clouds. Shower chances increase. Highs 61-68. Wind N 5-15 MPH.

DAYS 6-10 (MAY 30 – JUNE 3)

An upper low slowly departs to the east. An associated surface low can hold a shower chance in the region early that weekend and also trigger a pop up shower either afternoon, though it looks mostly dry. General pattern to start June puts New England under the eastern upper low member of an omega block. This is a cooler than normal pattern and carries a shower chance at some point as a disturbance goes by.

DAYS 11-15 (JUNE 4-8)

Indications are for cooler than average but also mostly dry with limited shower chances during this period as the aforementioned omega block continues but gradually weakens.

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)

Upper low pressure expected to be over the region for the final few days of May with below normal temperatures and a daily opportunity for spot showers, details TBD. High pressure builds in with fair weather to begin June as the upper low pulls to the east.

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.