Tuesday Forecast

7:31AM

DAYS 1-5 (FEBRUARY 9-13)…
Trough of low pressure mills around for a few days and aids in the risk of snow showers and possibly a period of snow. On Friday, a new system drops out of Canada and brings a risk of some light snow then possibly a few snow squalls as an Arctic airmass arrives as this small system departs early Saturday.
TODAY: Mostly cloudy. Scattered snow showers through midday South Shore of MA, otherwise isolated flurries. Highs 25-32. Wind NE to N 5-15 MPH.
TONIGHT: Cloudy. Chance of snow overnight, especially southern MA and RI. Lows 18-25. Wind light variable.
WEDNESDAY: Mainly cloudy. Periods of snow, accumulating up to 1 inch through early afternoon, favoring southern and eastern MA as well as RI. Isolated heavier snow showers are possible. Highs 25-32. Wind variable 5-15 MPH.
THURSDAY: Variably cloudy. Chance of snow showers. Lows 15-22. Highs 25-32.
FRIDAY: Mostly cloudy. Chance of light snow mainly at night. Lows 15-22. Highs 25-32.
SATURDAY: Partly sunny. Chance of snow early. Risk of a brief snow squall. Temperatures fall through the 20s.

DAYS 6-10 (FEBRUARY 14-18)…
Fair weather Valentines Day February 14 and Presidents Day February 15, with extreme cold February 14 but easing on February 15. A system from the west brings a chance of snow/mix/rain by February 16-17. Fair and chilly February 18.

DAYS 11-15 (FEBRUARY 19-23)…Fair and cold February 19 followed by a warming trend February 20-21 with mostly dry weather continuing. Next threat of unsettled weather comes February 22-23 with rain/mix/snow possible.

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Monday Forecast

7:40AM

DAYS 1-5 (FEBRUARY 8-12)…
Big ocean storm just too far out for a big hit, so we’ll call this a hard side-swipe, and stay similar to the snow forecast from the last update. Wind will be pretty strong and coastal flooding at high tide times is a threat. Second storm late Tuesday to early Wednesday looks weak and snow should be limited, favoring southeastern areas. Still some snow showers possible as we transition to colder air late week.
TODAY: Overcast. Snow spreads northward and any mix near the South Coast turns to snow. Heaviest snow and blowing snow will occur over southeastern MA. Blizzard conditions are possible from Plymouth County of MA through Cape Cod and the Islands. Temperatures start out near 20 northwest of Boston and stay there, and fall from the lower 30s into the 20s to the southeast. Wind NE 15-35 MPH with higher gusts. Wind gusts may exceed 50 MPH along the coast especially south of Boston.
TONIGHT: Mostly cloudy. Snow tapering off from south to north. Total snow accumulation… 1-3 inches north central MA into south central NH, 3-6 inches Boston area west toward Worcester then south to northern RI, 6-9 inches southeastern MA into southern RI. Locally heavuier amounts are possible. Blowing snow reducing visibility at times. Lows 15-22. Wind N to NW 15-25 MPH with higher gusts.
TUESDAY: Mostly cloudy. Isolated snow showers day. Clouding up with a chance of snow at night, especially southern areas. Highs 25-32.
WEDNESDAY: Mostly cloudy. Chance of snow early, favoring southern and eastern areas. Another period of snow possible at night. Lows 15-22. Highs 28-35.
THURSDAY: Variably cloudy. Chance of snow showers. Lows 15-22. Highs 25-32.
FRIDAY: Variably cloudy. Chance of snow showers. Lows 15-22. Highs 25-32.

DAYS 6-10 (FEBRUARY 13-17)…
Fair weather over Valentines Day / Presidents Day Weekend but very cold February 13-14 and less cold February 15. A system from the west brings a chance of snow/mix/rain by February 16-17.

DAYS 11-15 (FEBRUARY 18-22)…Fair and colder February 18-19 followed by a warming trend February 20-21 with mostly dry weather continuing. Next threat of unsettled weather comes late in the period.

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Sunday Forecast Update / Storm Primer

8:12PM

IMPORTANT THINGS TO REMEMBER…
* When viewing a map on TV or the internet or reading my ranges here on the blog, pay attention to the snowfall forecast range, NOT just the top number! Assuming the forecast is correct, you will receive anywhere from the bottom number of the range to the top number of the range, and most likely something in between.
* Do not wake up first thing Monday morning and say “Where’s all the snow?! They are wrong again! I wish I could be wrong 90% of the time and still get paid!” Not that most of you would say the last thing. :) Remember, the storm is forecast to take place over the course of the day and into the evening. It will take time for the snow to accumulate.
* The term “blizzard” has NOTHING to do with snow accumulation. A blizzard is defined by 3 or more consecutive hours of winds frequently 35 MPH or greater, and visibility of under 1/4 mile in falling AND/OR blowing snow. It technically does not have to be snowing to have blizzard conditions, though a true ground blizzard is fairly rare in this part of the country, and more common in the Plains.

DAYS 1-5 (FEBRUARY 7-11)…
Cold front drops down from northern New England to supply some colder air tonight and Monday as low pressure deepens into a very strong and very broad storm system well offshore to the south and southeast of New England, but large enough to throw a significant shield of snow back into southern New England. A Winter Storm Warning is up for the WHW forecast area and a Blizzard Warning is up for Plymouth County of MA as well as all of Cape Cod, Martha’s Vineyard, and Nantucket. You can find the definition of blizzard above. The main time frame for the storm Monday will be from the pre-dawn hours to early evening in areas south of Boston, and from around dawn to mid evening from Boston north. A boundary, called a coastal front, is likely to set up early in the storm from near Boston southward through southeastern MA and down toward Cape Cod. East of this line, relatively milder air will mean a wetter, pasty snow to start, and with some trees already stressed from recent snow, there may be some additional trees and power lines coming down. West of this line, the snow will be a lighter and drier variety. This line will push to the east during the storm, and areas that start with wet snow will transition to a drier snow. Strongest winds will be found in coastal areas, especially southeastern MA (details to come below). Minor to moderate coastal flooding is likely at high tide times, especially along east-facing and north-facing shores. After this system moves beyond the region, the trough remains along the East Coast and additional energy will spawn another low which will be smaller and weaker than its predecessor. It should come close enough for some snow across parts of the region and I’ll fine-tune this tomorrow. Additional snow showers will be around both Wednesday, from the lingering trough in the area, and Thursday, from the passage of a cold front.
TONIGHT: Clouding up. Snow arrives South Coast pre-dawn, may be mixed with rain at first. Lows 18-25 southern NH and interior MA, 25-33 coastal MA to RI. Wind light NW to N.
MONDAY: Overcast. Snow spreads northward and any mix near the South Coast turns to snow. Heaviest snow and blowing snow will occur over southeastern MA. Blizzard conditions are possible from Plymouth County of MA through Cape Cod and the Islands. Temperatures start out near 20 northwest of Boston and stay there, and fall from the lower 30s into the 20s to the southeast. Wind NE 15-35 MPH with higher gusts. Wind gusts may exceed 45 MPH along the coast especially south of Boston.
MONDAY NIGHT: Mostly cloudy. Snow tapering off from south to north. Total snow accumulation… 2-5 inches Boston west and north, 5-9 inches southeastern MA into RI. Blowing snow reducing visibility at times. Lows 15-22. Wind N to NW 15-25 MPH with higher gusts.
TUESDAY: Mostly cloudy. Isolated snow showers day. Clouding up with a chance of snow at night, especially southern areas. Highs 25-32.
WEDNESDAY: Mostly cloudy. Chance of snow early, favoring southern and eastern areas. Another period of snow possible at night. Lows 15-22. Highs 28-35.
THURSDAY: Variably cloudy. Chance of snow showers. Lows 15-22. Highs 25-32.

DAYS 6-10 (FEBRUARY 12-16)…
Small clipper system brings cloudiness and a chance of a little light snow or a snow shower February 12 then opens the door to a shot of very cold Arctic air for the weekend February 13-14, easing up by Presidents Day February 15. A system from the west brings a chance of snow/mix/rain by February 16.

DAYS 11-15 (FEBRUARY 17-21)…
Some precipitation for at least part of February 17. Fair and colder February 18-19 followed by a warming trend February 20-21 with mostly dry weather continuing.

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Sunday Forecast

7:38AM

DAYS 1-5 (FEBRUARY 7-11)…
This update will nix in-depth discussion and save it for comments below as information comes in today. Overall, we’re still looking at a nice day today with plenty of sun and snow-melting, above-freezing temperatures. Clouds come in late from 2 directions: a high cloud shield from the south ahead of a developing ocean storm, and a band of clouds from the north along the leading edge of colder air, a cold front, which may trigger a snow shower in southern NH and northern MA by evening. The storm developing offshore will grow into a large-sized and very powerful ocean storm, but its orientation and size will be enough to throw moisture in the form of accumulating snow back into southeastern New England Monday. We’ll continue to watch the interaction of pieces of energy in a larger scale low pressure trough Tuesday-Thursday with additional opportunities for snow possible. At this time it looks like a second system may deliver a period of snow early Wednesday to parts of southern New England, but again timing and location of any snow area is uncertain, so just follow later updates.
TODAY: Sunshine much of the day, fading late behind advancing high clouds from the S, and also some cloudiness arriving in southern NH and northern MA from the north at the end of the day. Highs 38-45. Wind SW up to 10 MPH.
TONIGHT: Mostly cloudy. Chance of a snow shower southern NH to northern MA early. Snow developing southeastern MA and southern RI overnight. Lows in the 20s. Wind NW to NE 5-15 MPH with higher gusts.
MONDAY: Cloudy. Snow expanding northwestward across the region and continuing much of the day before becoming more intermittent and scattered at night. Blowing snow likely. UPDATED ACCUMULATION FORECAST… 4-8 inches except 8-14 inches in portions of southeastern MA and under 4 inches in north central MA and southwestern NH and under 8 inches outer Cape Cod and Nantucket. Temperatures steady in the 20s but may reach the 30s for a while immediate coast south of Boston and Cape Cod / Islands, before falling later. Wind NE 15-30 MPH with higher gusts especially coastal areas and southeastern MA. Blizzard conditions may exist in these areas for a few hours.
TUESDAY: Partial clearing but snow showers possible during the day/evening. Cloudy with a risk of snow returning overnight. Lows around 20. Highs around 30.
WEDNESDAY: Cloudy with a chance of snow morning. Variably cloudy with a chance of snow showers afternoon. Lows around 20. Highs around 30.
THURSDAY: Variably cloudy. Chance of snow showers. Lows around 20. Highs in the 30s.

DAYS 6-10 (FEBRUARY 12-16)…
Clipper system brings a chance of light snow later February 12 with seasonably cold air expected. Secondary Arctic front may deliver snow showers February 13 otherwise windy and turning much colder. Very cold, windy, and fair February 14. Moderating temperatures but snow risk increases February 15-16.

DAYS 11-15 (FEBRUARY 17-21)…
Overall drier weather though weak systems may produce passing snow showers at times. Temperatures near to slightly above normal for the period.

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Saturday Forecast

2:36AM

OVERVIEW…
We’re reaching a point in the ENSO cycle where El Nino is in its early stages of losing its grip on the weather, but not quite enough yet to completely let go. This is one of the reasons for a see-saw regime we’ll be in during the month of February, which started off quite warm (Boston being about 15F warmer than average for the first several day), will turn much colder for the coming week overall before moderating, only to head back to the cold side beyond mid month.

DAYS 1-5 (FEBRUARY 6-10)…
Watch for icy ground if you are going to be out in the early to mid morning hours today. Untreated surfaces will likely be icy! As it warms above freezing during the day and is dry, the icy areas will melt then likely dry off, though some remaining damp or wet spots that don’t dry off may re-freeze tonight. During this weekend a wave of low pressure will pass well north of the region and a weak disturbance trailing from it will bring some cloudiness today and again later Sunday. After this, a complex weather situation evolves in which a broad trough of low pressure takes up residence along the East Coast and a series of storms results over a fairly short period of time. Currently, the thought process is that the first of these will evolve into a large ocean storm Sunday night and Monday, moving a pretty good distance south and east of New England, but the storm bring large enough to toss back some moisture for at least snow showers and perhaps a period of steadier snow. As this system moves out, a second storm is expected to develop and track closer to the coast. It is unclear at this point how quickly this storm intensifies and its exact track and configuration. Therefore, the only thing that can be said with any reasonable amount of confidence at this point is that there will be a chance of snow/mix/rain for at least parts of the region for a portion of Tuesday into Wednesday. Much fine-tuning will be needed in the coming few days.
TODAY: Sunshine starts and ends the day but is interrupted in between by a period of cloudiness. Highs 33-40. Wind SW 5-15 MPH with higher gusts.
TONIGHT: Mostly clear. Lows 15-20 interior valleys, 20s elsewhere. Wind light W.
SUNDAY: Mostly sunny to partly cloudy. Highs 35-42. Wind W 5-15 MPH becoming variable.
SUNDAY NIGHT: Increasing clouds. Lows 18-25. Wind N to NE 5-15 MPH.
MONDAY: Cloudy. Chance of snow or snow showers. Highs 25-32.
TUESDAY: Cloudy. Chance of snow/mix/rain. Lows in the 20s. Highs in the 30s.
WEDNESDAY: Mostly cloudy. Chance of snow showers. Lows 15-25. Highs 25-35.

DAYS 6-10 (FEBRUARY 11-15)…
Cold with possible snow showers February 11. A clipper system may bring some snow or snow showers later February 12 into early February 13 followed by a blast of Arctic air February 13 into early February 14. Moderating temperatures but with a chance of snow/mix February 15, based on current medium range timing.

DAYS 11-15 (FEBRUARY 16-20)…
The colder pattern eases up and temperatures become more variable but mostly near to slightly above normal. A possible snow/mix event exits early in the period and another disturbance may follow that up rather quickly with additional precipitation chances.

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Friday Forecast

7:24AM

DAYS 1-5 (FEBRUARY 5-9)…
An active period of weather with today’s event, a big ocean storm missing, and another storm threat later in the period. Will skip the detailed discussion and just re-update the forecast, focused on today’s event and adding the outlook going forward. More on upcoming events in an extra post this evening.
TODAY: Cloudy through mid afternoon with snow except rain/mix turning to snow west to east Cape Cod and Islands, accumulations generally 4-8 inches with a locally higher amount possible, except 2-4 inches most of Cape Cod and 1-2 inches Nantucket and outer Cape Cod. Clearing late in the day with best chance of sunshine from Boston westward very late. Temperatures steady in the 30s, lowest northwest of Boston, highest Cape Cod. Wind NE to N 10-20 MPH with higher gusts.
TONIGHT: Mostly clear. Lows in the 20s. Wind NW 5-15 MPH.
SATURDAY: Mostly sunny. Highs in the 40s. Wind W 5-15 MPH.
SUNDAY: Partly sunny. Chance of snow showers. Lows in the 20s. Highs in the 30s.
MONDAY: Mostly cloudy. Chance of snow showers. Lows in the 20s. Highs in the 30s.
TUESDAY: Cloudy with snow/mix/rain possible. Lows in the 20s. Highs in the 30s.

DAYS 6-10 (FEBRUARY 10-14)…
Windy and colder with snow showers possible February 10. Fair and cold February 11. Clipper system brings a risk of snow showers February 12. Fair and very cold February 13-14.

DAYS 11-15 (FEBRUARY 15-16)…
A little uncertainty this period. Variable temperatures. Risk of snow/mix February 15-16 then mainly fair weather returning.

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Thursday Forecast Update

3:29PM

DAYS 1-5 (FEBRUARY 4-8)…
As we fine-tune the upcoming event we find a westward shift, enough to bring heavier snow into the I-95 belt. This is due to a 20 to 40 mile westward shift in the position of the front and track of the low pressure area developing along it – a rather small distance in the grand picture but in this case it has big impacts on the location of heavier snowfall. So this update takes that into account and adjusts for it. The remainder of the forecast below is largely unchanged at this time. Will update that on the next post…
THROUGH EVENING: Mostly cloudy. Temperatures cooling into the 40s. Wind NW 5-15 MPH.
TONIGHT: Mainly cloudy. Rain/mix developing south to north overnight, changing to snow by dawn except only mixing with snow on the immediate South Shore though Cape Cod and the South Coast. Lows in the 30s. Wind NW to N 5-15 MPH.
FRIDAY: Cloudy through early afternoon with snow except rain and snow mixed South Shore through Cape Cod, accumulations under 1 inch outer Cape Cod and Nantucket, 1-3 slushy inches remainder of Cape Cod, South Shore of MA and South Coast of MA including southern RI, 3-6 inches elsewhere except an area of 6-9 inches along the I-95 belt from northeastern MA to north central RI. Clearing during the afternoon. Temperatures steady in the 30s, lowest northwest of Boston, highest Cape Cod. Wind NE to N 10-20 MPH with higher gusts.
SATURDAY: Mostly sunny. Lows in the 20s. Highs in the 40s.
SUNDAY: Partly sunny. Chance of snow showers. Lows in the 20s. Highs in the 30s.
MONDAY: Increasing clouds. Lows in the 20s. Highs in the 30s.

DAYS 6-10 (FEBRUARY 9-13)…
A trough of low pressure will remain in the area February 9 with additional storm development possible. Rain/mix/snow (depending on development and track) is possible on February 9. Windy and colder with snow showers possible February 10. Fair and cold February 11. Smaller system may bring some mix/snow February 12, reinforcing cold air for the end of the period.

DAYS 11-15 (FEBRUARY 14-18)…
Mostly fair weather with temperatures below normal to start the period then recovering to closer to normal.

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Thursday Forecast

7:27AM

DAYS 1-5 (FEBRUARY 4-8)…
Trying to fine-tune this forecast as a frontal boundary sits just offshore through early Friday, cold air slowly works in, and low pressure ripples move along the front. The final ripple will bring the threat of some accumulating snow to eastern and southeastern MA as well as RI early Friday, with a fairly sharp cut-off between accumulating snow and no snow at all. Current thinking places this line near the MA/NH border near the Merrimack River southwestward along the I-495 area and down to about northwestern RI. The greatest chance for significant snow will be interior southeastern MA where the combination of the coldest air and the heaviest precipitation is expected. This is not going to be a major snowstorm, but the timing is not the greatest as areas that do get the steadiest snow will likely have it occurring during commute time on Friday morning. Conditions will improve quickly Friday afternoon. Before all of this happens, the mild air that came in during Wednesday will hang around for much of Thursday. Additional patches of light rain are possible in RI, eastern MA, and southeastern NH during Thursday morning before it tries to clear out for a while ahead of the Friday morning event. By the time we get to the weekend, we’ll have a seasonably chilly and dry Saturday. A cold front will drop through the region from northwest to southeast Sunday, possibly producing a few snow showers, and reinforcing some colder air. Monday, the cold air will be established and an ocean storm will evolve but likely remain offshore far enough to spare this region impact.
TODAY: Mainly cloudy morning with additional rain RI through southeastern MA and a few rain showers elsewhere. Partial sun possible afternoon. Highs in the 50s through midday then cooling off slowly. Wind SW 5-15 MPH shifting to NW.
TONIGHT: Mainly cloudy. Rain/mix developing south to north overnight, changing to snow by dawn. Lows in the 30s. Wind NW to N 5-15 MPH.
FRIDAY: Cloudy through midday with snow, accumulating 1-3 inches except less than 1 inch northwest of I-495 north of the Mass Pike and 3-6 inches from the South Shore to eastern RI. A very small area of over 6 inches is possible interior southeastern MA. Clearing afternoon. Temperatures steady in the 30s. Wind N to NW 5-15 MPH with higher gusts.
SATURDAY: Mostly sunny. Lows in the 20s. Highs in the 40s.
SUNDAY: Partly sunny. Chance of snow showers. Lows in the 20s. Highs in the 30s.
MONDAY: Increasing clouds. Lows in the 20s. Highs in the 30s.

DAYS 6-10 (FEBRUARY 9-13)…
A trough of low pressure will remain in the area February 9 with additional storm development possible. Rain/mix/snow (depending on development and track) is possible on February 9. Windy and colder with snow showers possible February 10. Fair and cold February 11. Smaller system may bring some mix/snow February 12, reinforcing cold air for the end of the period.

DAYS 11-15 (FEBRUARY 14-18)…
Mostly fair weather with temperatures below normal to start the period then recovering to closer to normal.

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Wednesday Forecast

7:32AM

DAYS 1-5 (FEBRUARY 3-7)…
Low pressure tracks northwest of New England as it heads into Canada through tonight. A surge of mild air moves up from the south ahead of it with gusty winds and eventual rain including some downpours. The low’s cold front gets offshore but not that far before hanging up. A ripple of low pressure will move up along the front Thursday night and early Friday, close enough for a grazing of rain/snow over Cape Cod and southeastern MA. The weekend will be mostly fair and turning colder. A cold front passing by on Sunday may produce a few rain and snow showers.
TODAY: Cloudy. A chance of light rain northwest of Boston by midday but rain more likely a band moving from west to east mid to late afternoon. Highs in the 50s but for some areas not until late in the day. Wind SE to S 10-20 MPH with higher gusts.
TONIGHT: Cloudy. Rain likely, including embedded downpours and a slight chance of thunderstorms, diminishing west to east overnight. Temperatures may rise toward 60 at first then lows in the 40s late. Wind S to SW 15-25 MPH with higher gusts, shifting to W toward dawn.
THURSDAY: Partly sunny. Rain may linger outer Cape Cod firs thing in the morning. Highs in the 50s. Wind W 10-20 MPH with higher gusts.
FRIDAY: Chance of rain/snow Cape Cod and southeastern MA early, otherwise mostly cloudy start then clearing with sun returning. Lows in the 30s. Highs in the 40s.
SATURDAY: Mostly sunny. Lows in the 20s. Highs in the 40s.
SUNDAY: Partly cloudy. Chance of a few rain and snow showers. Lows in the 20s. Highs 35-45.

DAYS 6-10 (FEBRUARY 8-12)…
Unsure of details at this time, but a colder period of weather and a couple potential storms may impact the region. Will work on timing and refine this outlook.

DAYS 11-15 (FEBRUARY 13-17)…
Indications are for below normal temperatures but drier weather during this time.

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Tuesday Forecast

7:29AM

DAYS 1-5 (FEBRUARY 2-6)…
Groundhogs may be searching for shadows this morning but we’re searching for what the weather will really be, and the computer models may be more confused than any groundhog will be. Inconsistency in model runs leads me to leave ideas generally the same going forward today. The only adjustment will be to slightly slow the timing of the front coming through Wednesday.
TODAY: Mostly sunny. Highs in the 40s. Wind light variable.
TONIGHT: Increasing clouds. Lows around 40. Wind SE 5-15 MPH.
WEDNESDAY: Cloudy. Rain showers likely in the afternoon. Highs in the 50s. Wind SE 10-20 MPH with higher gusts, shifting to SW late.
THURSDAY: Early rain Cape Cod. Clearing west to east. Lows around 40. Highs around 50.
FRIDAY: Mostly sunny. Lows around 30. Highs around 40.
SATURDAY: Partly cloudy. Lows in the 20s. Highs in the 30s.

DAYS 6-10 (FEBRUARY 7-11)…
A few snow shower possible with the passage of a cold front sometime on February 7. Fair and slightly colder weather is expected for February 8 and 9. A storm threat exists for the region with a risk of rain and snow about February 10-11.

DAYS 11-15 (FEBRUARY 12-16)…
Additional unsettled weather possible around the middle of the month with a better chance for snow than we’ve seen many times previously. Temperatures near to below normal. This outlook is still fairly low confidence at this time.

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