C-19 Chat Post – May 9 2020

7:44AM

DAYS 1-5 (MAY 8-12)

High pressure brings nice weather to start today but clouds will be on the advance ahead of a cold front and developing low pressure system later, and tonight we’ll turn wet with rain arriving, but as the front pushes through the region and anomalous cold both surface and aloft arrive, we’re going to see rain flip to snow in the pre-dawn hours of Saturday in the higher elevations of central MA and southwestern NH to start, and then as the low pressure system, tracking northeastward close to the South Coast, starts to pull away, the mix/snow line will try to advance toward the coast. Now keeping in mind that it’s May, the worst that is likely to happen is up to an inch or so of slushy accumulation on unpaved surfaces in higher elevations and maybe a quick coating on grassy areas a little further southeast, into the Boston suburbs, which would melt in rapid fashion after daybreak Saturday, even if there were still flakes in the air for a while. Nevertheless we’ll be left with a blustery and unseasonably chilly Saturday, with lots of clouds and a passing shower of rain or even mixed rain/snow over the hills. This improves to a sunnier Sunday, still with some passing clouds, a breezy but not as windy, and a chilly feel to the air but not as cold as Saturday. I also think that we may be saved from a frost and potential late season freeze by the breeze that will keep the air mixed Sunday morning so the temperature doesn’t fall to it’s potential lowest level. At least this Mother’s Day won’t be rainy, mixed with sleet in some areas, like 2019’s. We’d also have to worry about a frost/freeze Sunday night / Monday morning, but I think the rapid movement of weather systems means a blanket of clouds will already be in place to keep temperatures in check. Another slug of rain is expected Monday with the passage of the next low pressure area, but this time rain, no snow involved. That moves away quickly and is replaced by high pressure with fair, cool weather Tuesday.

TODAY: Sunny start, cloudy finish. Highs 56-63. Wind W 5-15 MPH, gusts over 20 MPH.

FRIDAY NIGHT: Cloudy. Rain arrives, changes to snow pre-dawn southwestern NH and central MA higher elevations with up to 1 inch possible on cold surfaces, may mix with snow into northwestern suburbs of Boston with a possible coating on grassy surfaces and car tops. Lows 33-40. Wind S 5-15 MPH early evening, shifting to N with higher gusts late evening.

SATURDAY: Cloudy early-mid morning with snow/mix northwest of Boston, rain/mix around Boston, rain to the southeast, tapering off west to east. Mostly cloudy with passing showers of rain/mix possible thereafter. Highs 42-49. Wind NW 15-25 MPH, higher gusts.

SATURDAY NIGHT: Clearing. Lows 32-39. Wind NW 5-15 MPH.

SUNDAY: Sunny start mixed sun and clouds. Highs 52-59. Wind NW 10-20 MPH.

SUNDAY NIGHT: Mostly cloudy. Lows 40-47. Wind N 5-15 MPH.

MONDAY: Cloudy. Periods of rain. Highs 48-55. Wind NE 5-15 MPH.

MONDAY NIGHT: Cloudy with a chance of rain or drizzle early, then clearing. Lows 38-45. Wind N 5-15 MPH.

TUESDAY: Sun and passing clouds. Highs 55-62. Wind NW 10-20 MPH.

DAYS 6-10 (MAY 13-17)

General west to east flow pattern expected. Current timing would have it cool with a disturbance bringing the risk of a passing rain shower May 13, then dry and milder May 14. A system passing north of the region brings clouds and a brief wet weather threat later May 15 to early May 16 followed by fair and briefly cooler then milder through May 17.

DAYS 11-15 (MAY 18-22)

General pattern in this time frame looks zonal (west to east) and more relaxed toward seasonably milder with a couple minor rainfall threats.

C-19 Chat Post – May 8 2020

7:37AM

DAYS 1-5 (MAY 7-11)

Low pressure moves away and we get a sliver of sunshine for a while, but the atmosphere is a bit unstable and that combined with an approaching trough means some clouds will develop and may lead to a spot rain shower this afternoon, and an additional rain shower tonight as the trough passes. Ah, so that means clearing tomorrow right? Wrong. Another low pressure area approaches, and while we may start the day with some sunshine Friday, we’ll end it with an overcast that will remind you have the sky just before a winter storm, and how ironic, because with enough cold air around, parts of the region will indeed see some May snowflakes with the low pressure area passing by Friday night and Saturday. Is this a set-up similar to the historic snowstorm of May 9-10 1977? Yes and no. Similar, but not quite as extreme, so at this point, despite you seeing or possibly hearing about model runs that bring significant snow amounts, for May, to near the coast, that is very unlikely to take place. Focus on interior higher elevations of north central MA and southwestern NH for the best place to see some snow accumulation in the early hours of Saturday from this system, but not out of the question that some mixing can take place at a few lower elevations to the south and east of there depending on how hard it precipitates. Either way, we’ll be feeling some unseasonably cold air on Saturday, which may set a record for the lowest high temperature for the date in many areas. Conditions improve on Sunday somewhat, as it will be a brighter Mother’s Day but will remain chilly for the season and also breezy. When we get to Monday yet another low pressure area will make a run at the region but this one looks weaker and should track further south. The air will also have moderated to milder overall (though still cooler than average). This system could largely miss but leaving a rain risk in the forecast.

TODAY: Sunshine to start then clouds popping up with a possible rain shower. Highs 48-55. Wind N 10-20 MPH.

TONIGHT: Lots of clouds. A possible rain shower. Lows 37-44. Wind N 5-15 MPH.

FRIDAY: Some sunshine then clouding over. Highs 50-57, coolest Cape Cod. Wind N 5-15 MPH.

FRIDAY NIGHT: Cloudy. Rain likely, may mix with or turn to snow across interior higher elevations of northern MA and southwestern NH. Lows 33-40. Wind NE 10-20 MPH, higher gusts especially coastal areas.

SATURDAY: Mostly cloudy. Showers of rain, possibly rain/snow mix higher elevations interior northern MA and southwestern NH. Highs 42-49. Wind NW 15-25 MPH, higher gusts.

SATURDAY NIGHT: Clearing. Lows 32-39. Wind NW 5-15 MPH.

SUNDAY: Sunny start then lots of clouds popping up. Highs 52-59. Wind NW 10-20 MPH.

SUNDAY NIGHT: Mostly cloudy. Lows 40-47. Wind N 5-15 MPH.

MONDAY: Cloudy. Chance of rain. Highs 48-55. Wind NE 5-15 MPH.

DAYS 6-10 (MAY 12-16)

General west to east flow pattern expected. Current timing would have it dry and cool May 12, still cool with a disturbance bringing the risk of a passing rain shower May 13, then dry and milder May 14. A system passing north of the region brings clouds and a brief wet weather threat later May 15 to early May 16 followed by fair and cooler weather.

DAYS 11-15 (MAY 17-21)

General pattern in this time frame looks zonal (west to east) and more relaxed toward seasonably milder with a couple minor rainfall threats.

C-19 Chat Post – May 7 2020

7:33AM

DAYS 1-5 (MAY 6-10)

Low pressure heads our way for tonight but before it arrives a good part of today will be nice as high pressure attempts to retain control. The day that starts sunny will end cloudy however as the low advances in this direction, its track taking it just south of New England early Thursday. This will be a rain producer but a few mixed in wet snowflakes cannot be ruled out if the rain falls heavily enough, and this is most likely over southeastern MA in the pre-dawn hours of Thursday. During the day Thursday clouds may break for a bit of sun but another trough of low pressure swinging through from west to east in the evening may produce an additional shower, and behind this comes a shot of unseasonably chilly air for May, setting up an interesting scenario for the next low pressure area, set to impact the region later Friday into Saturday. This one will take a similar track to the first one, but with colder air to work with, and precipitation expected to be a little more substantial, enough cold air can work down to mix it with or even change it to snow across higher elevations of southwestern NH and north central MA, where is where any accumulation (on non-paved surfaces) would take place. I can’t even rule out wet snow mixing in close to Boston. Once the main precipitation shield exits early Saturday, we’ll be left with a blustery day and a few rain/mix/snow showers, depending on your location. Flakes would still be most likely at interior higher elevations, but it will definitely feel more like a March day than one coming in nearly mid May, and very much in contrast to last weekend. Last year’s Mother’s Day was cold and wet with rain, and even some ice pellets mixed in. This year’s will be cool, but breezy and dry, as we’ll still be in the chilly air flow behind Saturday’s storm system. So the next 5 days will be a throw back to early spring, for sure.

TODAY: Sunshine then increasing clouds. Highs 53-60, coolest coast. Wind variable up to 10 MPH with sea breezes.

TONIGHT: Cloudy. Rain developing. Rain may mix with wet snow briefly in some locations, favoring southeastern MA. Lows 37-44. Wind NE 10-20 MPH, strongest near the coast with gusts around or above 30 MPH Cape Cod.

THURSDAY: Cloudy start with rain possible eastern areas. Breaking clouds later. Highs 48-55. Wind N 10-20 MPH.

THURSDAY NIGHT: Lots of clouds. A possible rain shower. Lows 37-44. Wind N 5-15 MPH.

FRIDAY: Mostly cloudy. Highs 50-57, coolest Cape Cod. Wind N 5-15 MPH.

FRIDAY NIGHT: Cloudy. Rain likely, may mix with or turn to snow across interior higher elevations of northern MA and southwestern NH. Lows 33-40. Wind NE 10-20 MPH, higher gusts especially coastal areas.

SATURDAY: Mostly cloudy. Showers of rain, possibly rain/snow mix higher elevations interior northern MA and southwestern NH. Highs 42-49. Wind NW 15-25 MPH.

SATURDAY NIGHT: Clearing. Lows 32-39. Wind NW 5-15 MPH.

SUNDAY: Sun and passing clouds. Highs 52-59. Wind NW 10-20 MPH.

DAYS 6-10 (MAY 11-15)

Rain risk May 11 and dry May 12-13 with temperatures below normal. Milder May 14-15 with dry weather May 14 and a rain shower risk May 15.

DAYS 11-15 (MAY 16-20)

Dry start and end to period with some unsettled weather mid period during a transition to a milder pattern.

C-19 Chat Post – May 6 2020

7:41AM

DAYS 1-5 (MAY 5-9)

We’re heading back to the cooler side of normal for the next several days, and you’ll really notice it by the end of this 5-day forecast period. Of these 5 days, today is probably the nicest of them all as high pressure controls the weather. It’s a cooler Canadian high but will provide dry weather, although the day starts out breezy before winds subside. Low pressure makes a run at the region later Wednesday, passing southeast of New England with the slug of rain, most of it falling Wednesday night, though clouds hang around Thursday as that low departs and a trough approaches from the west, perhaps triggering an additional rain shower. The next low pressure area will already be on the approach Friday so don’t expect much clearing for that day either, and this system will be a bit more potent as it passes, but once again it looks like the bulk of the steadiest precipitation will occur in the nighttime hours Friday to very early Saturday. This time, enough cold air will be involved so that some mixing or even a chance to snow is possible across the interior higher elevations. As the system pulls away on Saturday it will be blustery and unseasonably chilly for May with showers of rain and even mixed rain/snow across the interior hills continuing…
TODAY: Mostly sunny. Highs 53-60. Wind N 10-20 MPH then diminishing.
TONIGHT: Partly cloudy. Lows 36-43. Wind variable up to 10 MPH.
WEDNESDAY: Increasing clouds. Highs 53-60, coolest coast. Wind variable up to 10 MPH with sea breezes.
WEDNESDAY NIGHT: Cloudy. Rain developing. Lows 42-49. Wind NE 10-20 MPH, strongest near the coast with gusts around or above 30 MPH Cape Cod.
THURSDAY: Mostly cloudy. Risk of rain showers. Highs 50-57. Wind NE 5-15 MPH early becoming variable.

THURSDAY NIGHT: Lots of clouds. A possible rain shower. Lows 37-44. Wind N 5-15 MPH.
FRIDAY: Mostly cloudy. Highs 50-57, coolest Cape Cod. Wind N 5-15 MPH.

FRIDAY NIGHT: Cloudy. Rain likely, may mix with or turn to snow across interior higher elevations of northern MA and southwestern NH. Lows 33-40. Wind NE 10-20 MPH, higher gusts especially coastal areas.

SATURDAY: Mostly cloudy. Showers of rain, possibly rain/snow mix higher elevations interior northern MA and southwestern NH. Highs 42-49. Wind NW 15-25 MPH.

DAYS 6-10 (MAY 10-14)

Fair, very cool May 10. Temperatures continue below normal overall but not quite as chilly with 1 or 2 minor systems with rain shower threats between May 11 and May 14.

DAYS 11-15 (MAY 15-19)

Temperatures trend a little closer to normal with a mid period risk of rain showers.

C-19 Chat Post – May 5 2020

7:45AM

DAYS 1-5 (MAY 4-8)
When I put a link to my colleague’s blog in the comments below, I suspect you’ll find similar forecasts between the two of us – nothing unusual there. He’s going to tell you that today will be the warmest day this week, which it will be, and that it won’t be as wet as last week, which it won’t be, but it’s going to turn quite cool, which it will, and that some areas may not have seen their final snowflakes of the season, which they may have not, but that threat is outside of my first section here as I suspect that risk to occur next weekend. So, let’s rewind a bit and summarize that as low pressure departs offshore we actually start the week with a clearing morning and mild air. This afternoon, a trough swings through with lots of clouds and spot showers. Any of these showers may be briefly heavy, but if you encounter one, it won’t last long at all. This is the leading edge of the cooler air that is the first of a few pushes, each one progressively cooler than the last. The second one will arrive behind low pressure that tracks southeast of New England late Wednesday and early Thursday, the precipitation largely staying offshore but a northward extension of low pressure or inverted trough probably bringing some showery conditions for a while Wednesday night into Thursday. A trough swings through Thursday night with an additional rain shower possible and this sends a push of even cooler air in on Friday ahead of the next low pressure system, which brings more cloudiness back in on Friday and the threat of some wet weather by Friday night, although this is somewhat uncertain at this time.
TODAY: Clouds over southeastern MA and RI and perhaps a brief touch of rain outer Cape Cod early morning otherwise increasing sunshine. Midday and afternoon clouds returning from northwest to southeast with isolated to scattered showers and possibly a few brief downpours. Highs 60-67. Wind variable up to 10 MPH morning, NW 10-20 MPH with higher gusts this afternoon.
TONIGHT: Clearing. Lows 35-42. Wind N 10-20 MPH, diminishing overnight.
TUESDAY: Mostly sunny. Highs 53-60. Wind N up to 10 MPH.
TUESDAY NIGHT: Partly cloudy. Lows 36-43. Wind variable up to 10 MPH.
WEDNESDAY: Increasing clouds. Highs 53-60, coolest coast. Wind variable up to 10 MPH with sea breezes.
WEDNESDAY NIGHT: Cloudy. Rain showers developing. Lows 43-50. Wind variable to N 5-15 MPH.
THURSDAY: Cloudy morning with rain showers likely. Breaking clouds afternoon. Highs 50-57, coolest Cape Cod. Wind NE-N 5-15 MPH.
THURSDAY NIGHT: Lots of clouds. A possible rain shower. Lows 37-44. Wind N 5-15 MPH.
FRIDAY: Mostly cloudy. Highs 50-57, coolest Cape Cod. Wind N 5-15 MPH.

DAYS 6-10 (MAY 9-13)
A very cool May 9-10 weekend including a period of unsettled weather that will be mainly in the form of rain showers however at some point there could be mix or snow showers across the interior higher elevations. Mostly dry to follow but temperatures still below normal.

DAYS 11-15 (MAY 14-18)
Cool and dry to start period. Milder trend follows, some unsettled weather returns.

C-19 Chat Post – May 4 2020

8:33AM

DAYS 1-5 (MAY 3-7)
My college professors would probably call what is passing through this morning a “baroclinic zone” and not a front. Whatever it is, cloudiness and maybe a sprinkle accompany it, and behind it comes more plentiful sunshine and the warmest day in quite some time, again with a caveat of the typical cooler spots where a west wind does blow over water before crossing land again (outer Cape Cod for example). Enjoy today, because a transition back to cooler weather begins tomorrow, although our pattern these 5 days will be drier than recently. First, a wave of low pressure may briefly wet the South Coast early Monday before a cold front pushes northwest to southeast across the entire area during the day. High pressure will be in general control Tuesday and Wednesday before a weak low approaches during Thursday.
TODAY: Lots of clouds and a possible sprinkle of rain through mid morning then mostly sunny. Highs ranging from around 55 outer Cape Cod and Nantucket to 70-75 interior valleys. Wind W 5-15 MPH.
TONIGHT: Clouding over. Risk of rain South Coast overnight. Lows 50-57. Wind W up to 10 MPH.
MONDAY: Mostly cloudy. Risk of rain favoring the South Coast early. Slight risk of a rain shower anywhere else during the day. Highs 56-63,
coolest coast. Wind variable up to 10 MPH morning, N 10-20 MPH afternoon.
MONDAY NIGHT: Partly cloudy. Lows 45-52. Wind N 5-15 MPH.
TUESDAY: Partly sunny. Highs 55-62. Wind N up to 10 MPH.
TUESDAY NIGHT: Mostly cloudy. Lows 45-52. Wind variable up to 10 MPH.
WEDNESDAY: Partly sunny. Highs 55-62. Wind N 5-15 MPH.
WEDNESDAY NIGHT: Partly cloudy. Lows 48-55. Wind variable under 10 MPH.
THURSDAY: Mostly cloudy. Chance of rain showers late. Highs 60-67. Wind S up to 10 MPH.

DAYS 6-10 (MAY 8-12)
Risk of rain May 8 with a frontal boundary in the area. Much cooler, potentially near record setting cold, during the May 9-12 period. Uncertainly as to whether or not a storm system threatens around May 9 but the overall trend should be drier. Much fine-tuning to be done.

DAYS 11-15 (MAY 13-17)
Cool and dry to start period. Milder trend follows, some unsettled weather returns.

C-19 Chat Post – May 3 2020

9:31AM

DAYS 1-5 (MAY 2-6)
The first weekend of May will be quite nice, and given that it’s coming in an overall pattern that is still cooler and wetter than average, we’re getting lucky. If you can safely enjoy some outside time, these next 2 days are the time to do it. You’ll have to endure a gusty breeze today, but the air will be quite mild in comparison to many recent days. The air aloft is still chilly enough so the sun’s heating of ground still a little wet from yesterday’s rainfall should combine to pop some cumulus clouds. On Sunday you’ll have to wait out some morning cloudiness and a passing rain shower threat, but if you’re looking for sunshine that will return by late morning or midday at the latest, lastly toward Cape Cod. But the reminder that we’re in the same general pattern comes the first few days of next week when we’ll watch a couple waves of low pressure. Interestingly, there is some significant model disagreement on how these features will track and interact with each other, but for now I am just going with the same general idea I had on yesterday’s update, and will make adjustments tomorrow if necessary. I think early Monday and later Tuesday to early Wednesday are the times when waves of low pressure will pass south of the region, all the while a larger circulation of low pressure being blocked from exiting North America via the Maritime Provinces of Canada will wobble its way east southeastward just north of New England and situate itself offshore. This means that regardless of any rainfall threat, the cooler weather will be returning after our mild weekend.
TODAY: Mostly sunny – some passing clouds. Highs 55-60 Cape Cod, 60-67 elsewhere. Wind NW 10-20 MPH, higher gusts at times.
TONIGHT: Increasing clouds. Risk of rain showers overnight. Lows 50-57. Wind W 5-15 MPH.
SUNDAY: Mostly cloudy through mid morning including a risk of rain showers. Sun returning west to east late morning on. Highs 55-62 South Coast, 63-70 elsewhere. Wind W 5-15 MPH.
SUNDAY NIGHT: Clouding over. Risk of rain favoring southern areas overnight. Lows 48-55. Wind N up to 10 MPH.
MONDAY: Mostly cloudy. Risk of rain favoring the South Coast early. Slight risk of a rain shower anywhere else during the day. Highs 56-63,
coolest coast. Wind variable up to 10 MPH morning, N 10-20 MPH afternoon.
MONDAY NIGHT: Partly cloudy. Lows 45-52. Wind N 5-15 MPH.
TUESDAY: Increasing clouds. Risk of rain South Coast late. Highs 55-62. Wind variable up to 10 MPH.
TUESDAY NIGHT: Mostly cloudy. Risk of rain South Coast. Lows 45-52. Wind variable up to 10 MPH.
WEDNESDAY: Variably cloudy. Highs 55-62. Wind N 5-15 MPH.

DAYS 6-10 (MAY 7-11)
Temperatures below to much below normal. Greatest risk for unsettled weather middle of the period.

DAYS 11-15 (MAY 12-16)
Cool and dry to start period. Milder, risk of unsettled weather late period.

C-19 Chat Post – May 2 2020