Gale Warning 53, NWS Boston/Norton, MA

335 
WHUS71 KBOX 112056
MWWBOX

URGENT - MARINE WEATHER MESSAGE
National Weather Service Boston/Norton MA
356 PM EST Wed Dec 11 2019

ANZ250-251-254-120500-
/O.CON.KBOX.GL.W.0053.191212T0400Z-191212T1200Z/
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-Massachusetts Bay and Ipswich Bay-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
356 PM EST Wed Dec 11 2019

...GALE WARNING REMAINS IN EFFECT FROM 11 PM THIS EVENING TO 7 AM
EST THURSDAY...

* WHAT...Northwest winds 20 to 30 kt with gusts up to 35 kt and 
  seas 5 to 8 feet expected.

* WHERE...Coastal waters east of Ipswich Bay and the Stellwagen 
  Bank National Marine Sanctuary and Coastal waters from 
  Provincetown MA to Chatham MA to Nantucket MA out 20 nm.

* WHEN...From 11 PM this evening to 7 AM EST Thursday.

* IMPACTS...Strong winds will cause hazardous seas which could
  capsize or damage vessels and reduce visibility.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Mariners should alter plans to avoid these hazardous conditions.
Remain in port, seek safe harbor, alter course, and/or secure the
vessel for severe conditions.

&&

$$

ANZ255-256-120500-
/O.EXT.KBOX.SC.Y.0163.000000T0000Z-191212T1600Z/
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
356 PM EST Wed Dec 11 2019

...SMALL CRAFT ADVISORY NOW IN EFFECT UNTIL 11 AM EST THURSDAY...

* WHAT...Northwest winds 15 to 25 kt with gusts up to 30 kt and 
  seas 6 to 9 feet.

* WHERE...In Massachusetts coastal waters, Coastal Waters 
  extending out to 25 nm South of Marthas Vineyard and 
  Nantucket. In Rhode Island coastal waters, Coastal Waters from 
  Montauk NY to Marthas Vineyard extending out to 20 nm South of 
  Block Island.

* WHEN...Until 11 AM EST Thursday.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

ANZ235-237-120500-
/O.EXT.KBOX.SC.Y.0163.000000T0000Z-191212T1600Z/
Rhode Island Sound-Block Island Sound-
356 PM EST Wed Dec 11 2019

...SMALL CRAFT ADVISORY NOW IN EFFECT UNTIL 11 AM EST THURSDAY...

* WHAT...Northwest winds 10 to 20 kt with gusts up to 30 kt and 
  seas 4 to 7 feet.

* WHERE...Block Island Sound and Rhode Island Sound.

* WHEN...Until 11 AM EST Thursday.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

ANZ231>234-120500-
/O.EXT.KBOX.SC.Y.0164.191212T0000Z-191212T1500Z/
Cape Cod Bay-Nantucket Sound-Vineyard Sound-Buzzards Bay-
356 PM EST Wed Dec 11 2019

...SMALL CRAFT ADVISORY NOW IN EFFECT FROM 7 PM THIS EVENING TO
10 AM EST THURSDAY...

* WHAT...West winds 10 to 20 kt with gusts up to 30 kt expected.

* WHERE...Cape Cod Bay, Nantucket Sound, Vineyard Sound and 
  Buzzards Bay.

* WHEN...From 7 PM this evening to 10 AM EST Thursday.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

ANZ230-236-120500-
/O.CON.KBOX.SC.Y.0163.191212T0000Z-191212T0900Z/
Boston Harbor-Narragansett Bay-
356 PM EST Wed Dec 11 2019

...SMALL CRAFT ADVISORY REMAINS IN EFFECT FROM 7 PM THIS EVENING
TO 4 AM EST THURSDAY...

* WHAT...Seas 1 to 3 ft. NW wind gusts up to 25 knots. 

* WHERE...In Massachusetts coastal waters, Boston Harbor. In 
  Rhode Island coastal waters, Narragansett Bay.

* WHEN...From 7 PM this evening to 4 AM EST Thursday.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

BL

593 
WHUS71 KBOX 120206
MWWBOX

URGENT - MARINE WEATHER MESSAGE
National Weather Service Boston/Norton MA
906 PM EST Wed Dec 11 2019

ANZ250-251-254-121015-
/O.CON.KBOX.GL.W.0053.191212T0400Z-191212T1200Z/
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-Massachusetts Bay and Ipswich Bay-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
906 PM EST Wed Dec 11 2019

...GALE WARNING REMAINS IN EFFECT UNTIL 7 AM EST THURSDAY...

* WHAT...Northwest winds 15 to 25 kt with gusts up to 35 kt and 
  seas 4 to 7 feet expected.

* WHERE...Coastal waters east of Ipswich Bay and the Stellwagen 
  Bank National Marine Sanctuary, Massachusetts Bay and Ipswich 
  Bay and Coastal waters from Provincetown MA to Chatham MA to 
  Nantucket MA out 20 nm.

* WHEN...Until 7 AM EST Thursday.

* IMPACTS...Strong winds will cause hazardous seas which could 
  capsize or damage vessels and reduce visibility.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Mariners should alter plans to avoid these hazardous conditions.
Remain in port, seek safe harbor, alter course, and/or secure the
vessel for severe conditions.

&&

$$

ANZ255-256-121015-
/O.CON.KBOX.SC.Y.0163.000000T0000Z-191212T1600Z/
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
906 PM EST Wed Dec 11 2019

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 11 AM EST
THURSDAY...

* WHAT...Northwest winds 15 to 25 kt with gusts up to 30 kt and 
  seas 4 to 7 feet.

* WHERE...In Massachusetts coastal waters, Coastal Waters 
  extending out to 25 nm South of Marthas Vineyard and 
  Nantucket. In Rhode Island coastal waters, Coastal Waters from 
  Montauk NY to Marthas Vineyard extending out to 20 nm South of 
  Block Island.

* WHEN...Until 11 AM EST Thursday.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

ANZ235-237-121015-
/O.CON.KBOX.SC.Y.0163.000000T0000Z-191212T1600Z/
Rhode Island Sound-Block Island Sound-
906 PM EST Wed Dec 11 2019

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 11 AM EST
THURSDAY...

* WHAT...Northwest winds 10 to 20 kt with gusts up to 30 kt and 
  seas 4 to 6 feet.

* WHERE...Block Island Sound and Rhode Island Sound.

* WHEN...Until 11 AM EST Thursday.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

ANZ231>234-121015-
/O.CON.KBOX.SC.Y.0164.000000T0000Z-191212T1500Z/
Cape Cod Bay-Nantucket Sound-Vineyard Sound-Buzzards Bay-
906 PM EST Wed Dec 11 2019

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 10 AM EST
THURSDAY...

* WHAT...Northwest winds 10 to 20 kt with gusts up to 30 kt.

* WHERE...Nantucket Sound, Vineyard Sound, Cape Cod Bay and 
  Buzzards Bay.

* WHEN...Until 10 AM EST Thursday.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

ANZ230-236-120900-
/O.CON.KBOX.SC.Y.0163.000000T0000Z-191212T0900Z/
Boston Harbor-Narragansett Bay-
906 PM EST Wed Dec 11 2019

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 4 AM EST
THURSDAY...

* WHAT...West winds 10 to 20 kt with gusts up to 30 kt.

* WHERE...In Massachusetts coastal waters, Boston Harbor. In 
  Rhode Island coastal waters, Narragansett Bay.

* WHEN...Until 4 AM EST Thursday.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

130 
WHUS71 KBOX 120808
MWWBOX

URGENT - MARINE WEATHER MESSAGE
National Weather Service Boston/Norton MA
308 AM EST Thu Dec 12 2019

ANZ250-251-254-121200-
/O.CON.KBOX.GL.W.0053.000000T0000Z-191212T1200Z/
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-Massachusetts Bay and Ipswich Bay-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
308 AM EST Thu Dec 12 2019

...GALE WARNING REMAINS IN EFFECT UNTIL 7 AM EST THIS MORNING...

* WHAT...Northwest winds 15 to 25 kt with gusts up to 35 kt and 
  seas 4 to 7 feet expected.

* WHERE...Coastal waters east of Ipswich Bay and the Stellwagen 
  Bank National Marine Sanctuary, Massachusetts Bay and Ipswich 
  Bay and Coastal waters from Provincetown MA to Chatham MA to 
  Nantucket MA out 20 nm.

* WHEN...Until 7 AM EST this morning.

* IMPACTS...Strong winds will cause hazardous seas which could 
  capsize or damage vessels and reduce visibility.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Mariners should alter plans to avoid these hazardous conditions.
Remain in port, seek safe harbor, alter course, and/or secure the
vessel for severe conditions.

&&

$$

ANZ255-256-121615-
/O.EXT.KBOX.SC.Y.0163.000000T0000Z-191212T1700Z/
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
308 AM EST Thu Dec 12 2019

...SMALL CRAFT ADVISORY NOW IN EFFECT UNTIL NOON EST TODAY...

* WHAT...Northwest winds 15 to 25 kt with gusts up to 30 kt and 
  seas 4 to 7 feet.

* WHERE...In Massachusetts coastal waters, Coastal Waters 
  extending out to 25 nm South of Marthas Vineyard and 
  Nantucket. In Rhode Island coastal waters, Coastal Waters from 
  Montauk NY to Marthas Vineyard extending out to 20 nm South of 
  Block Island.

* WHEN...Until noon EST today.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

ANZ235-237-121500-
/O.EXT.KBOX.SC.Y.0163.000000T0000Z-191212T1500Z/
Rhode Island Sound-Block Island Sound-
308 AM EST Thu Dec 12 2019

...SMALL CRAFT ADVISORY NOW IN EFFECT UNTIL 10 AM EST THIS
MORNING...

* WHAT...Northwest winds 10 to 20 kt with gusts up to 30 kt and 
  seas 4 to 6 feet.

* WHERE...Block Island Sound and Rhode Island Sound.

* WHEN...Until 10 AM EST this morning.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

ANZ230-236-121200-
/O.EXT.KBOX.SC.Y.0163.000000T0000Z-191212T1200Z/
Boston Harbor-Narragansett Bay-
308 AM EST Thu Dec 12 2019

...SMALL CRAFT ADVISORY NOW IN EFFECT UNTIL 7 AM EST THIS
MORNING...

* WHAT...West winds 10 to 20 kt with gusts up to 30 kt.

* WHERE...In Massachusetts coastal waters, Boston Harbor. In 
  Rhode Island coastal waters, Narragansett Bay.

* WHEN...Until 7 AM EST this morning.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

ANZ231>234-121500-
/O.CON.KBOX.SC.Y.0164.000000T0000Z-191212T1500Z/
Cape Cod Bay-Nantucket Sound-Vineyard Sound-Buzzards Bay-
308 AM EST Thu Dec 12 2019

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 10 AM EST THIS
MORNING...

* WHAT...Northwest winds 10 to 20 kt with gusts up to 30 kt.

* WHERE...Nantucket Sound, Vineyard Sound, Cape Cod Bay and 
  Buzzards Bay.

* WHEN...Until 10 AM EST this morning.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

Frank

858 
WHUS71 KBOX 121122
MWWBOX

URGENT - MARINE WEATHER MESSAGE
National Weather Service Boston/Norton MA
622 AM EST Thu Dec 12 2019

ANZ250-251-254-121930-
/O.CAN.KBOX.GL.W.0053.000000T0000Z-191212T1200Z/
/O.EXB.KBOX.SC.Y.0164.000000T0000Z-191212T2100Z/
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-Massachusetts Bay and Ipswich Bay-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
622 AM EST Thu Dec 12 2019

...SMALL CRAFT ADVISORY IN EFFECT UNTIL 4 PM EST THIS AFTERNOON...
...GALE WARNING IS CANCELLED...

* WHAT...Northwest winds 10 to 20 kt with gusts up to 30 kt.

* WHERE...Coastal waters east of Ipswich Bay and the Stellwagen 
  Bank National Marine Sanctuary, Massachusetts Bay and Ipswich 
  Bay and Coastal waters from Provincetown MA to Chatham MA to 
  Nantucket MA out 20 nm.

* WHEN...Until 4 PM EST this afternoon.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

ANZ233-234-121230-
/O.CAN.KBOX.SC.Y.0164.000000T0000Z-191212T1500Z/
Vineyard Sound-Buzzards Bay-
622 AM EST Thu Dec 12 2019

...SMALL CRAFT ADVISORY IS CANCELLED...

Winds and seas have diminished below small craft levels.

$$

ANZ230-236-121230-
/O.CAN.KBOX.SC.Y.0163.000000T0000Z-191212T1200Z/
Boston Harbor-Narragansett Bay-
622 AM EST Thu Dec 12 2019

...SMALL CRAFT ADVISORY IS CANCELLED...

Winds and seas have subsided below small craft levels.

$$

ANZ235-237-121230-
/O.CAN.KBOX.SC.Y.0163.000000T0000Z-191212T1500Z/
Rhode Island Sound-Block Island Sound-
622 AM EST Thu Dec 12 2019

...SMALL CRAFT ADVISORY IS CANCELLED...

Winds and seas have diminished below small craft levels.

$$

ANZ255-256-121700-
/O.CON.KBOX.SC.Y.0163.000000T0000Z-191212T1700Z/
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
622 AM EST Thu Dec 12 2019

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL NOON EST TODAY...

* WHAT...Northwest winds 15 to 25 kt with gusts up to 30 kt and 
  seas 4 to 7 feet.

* WHERE...In Massachusetts coastal waters, Coastal Waters 
  extending out to 25 nm South of Marthas Vineyard and 
  Nantucket. In Rhode Island coastal waters, Coastal Waters from 
  Montauk NY to Marthas Vineyard extending out to 20 nm South of 
  Block Island.

* WHEN...Until noon EST today.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

ANZ231-232-121500-
/O.CON.KBOX.SC.Y.0164.000000T0000Z-191212T1500Z/
Cape Cod Bay-Nantucket Sound-
622 AM EST Thu Dec 12 2019

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 10 AM EST THIS
MORNING...

* WHAT...Northwest winds 10 to 20 kt with gusts up to 30 kt.

* WHERE...Nantucket Sound, Vineyard Sound, Cape Cod Bay and 
  Buzzards Bay.

* WHEN...Until 10 AM EST this morning.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

Area Forecast Discussion
National Weather Service Boston/Norton MA
1031 PM EST Tue Dec 10 2019

.SYNOPSIS...

A strong cold front crosses the region this evening, followed
by colder temperatures with showers changing to a period of
accumulating snow later tonight into Wednesday morning,
especially south of the Massachusetts Turnpike where a
significant impact may occur during the morning commute. Large
high pressure will bring cold and dry conditions Thursday and
Friday. Developing low pressure across the southeast U.S. will
shift up the coast with the potential for periods of heavy rain
Friday night into Saturday, possibly beginning as a period of
light snow across interior Massachusetts. Drier and cooler
weather returns Sunday into Monday. Another storm may impact
the region next Tuesday with snow or rain.

&&

.NEAR TERM /UNTIL 2 AM WEDNESDAY MORNING/...

1030 PM Update...

Forecast remains on track with rain beginning to transition to
snow across the higher terrain of MA. This process will occur
in the next few hours across most of interior MA/CT, reaching
eastern MA/RI by 3 or 4 AM, and the Cape by 7 AM.

We still think this looks like a general 1 to 4 inches of snow
across much of the region. Greatest risk for the higher amounts
will probably be across portions of the northeast CT and
Worcester Hills, as well as areas in the Foxboro/Sharon areas.
The reasoning is better forcing aligning with a bit of
elevation. May also see those higher amounts near the south
coast, where potential for better banding/snowgrowth may occur.
May see lower end totals, perhaps just a coating to 1 inch over
portions of the CT River Valley especially in western MA where
they are further removed from the forcing.

Still looks like a narrow window, where very strong jet dynamics
result in impressive 600-700 MB FGEN and snowgrowth. The
limiting factor will be the shorter duration as drier air
advecting into the region given WNW just off the deck.

Regardless of exact accumulations, main concern is briefly
moderate to heavy snow impacting the Wed AM commute in the
Hartford, to Providence, to Worcester and Boston metro areas.
Greatest concern will be across RI/SE MA where snow will persist
into the late morning hours.

&&

.SHORT TERM /2 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
7 PM Tuesday Update:

Incoming 18z guidance (NAM/GFS) and the RAP have come in a bit
wetter QPF-wise and shifted ever-so-slightly NW than earlier
iterations, especially in that 06-12z timeframe on I-95 SW of
Boston on to Providence into south-central RI, on into the Cape.
Some of which is almost double from its prior run. A good
fraction of this ends up being rain as this is the window in
which rain changes over, but I did opt to raise liquid-
equivalent QPF by about a tenth of an inch or so across SE
Mass/RI and a few hundredths higher N/W of I-95. That brings
about an increase in snow accumulations by an inch to inch and
half into SE Mass and on through RI, and less than a half-inch
increase further NW of I-95/Mass Pike. These changes didn't
necessitate any changes to headlines.

GFS continues to advertise an axis of mid-level frontogenetic
forcing that shifts SE into the early Wed AM period. If that
transpires, that FGen could organize some narrow snowbands into
the I-95 corridor S of Boston, with moderate/heavy snow in them
at times.

Will defer any further adjustments until the 00z guidance comes
in.

Prior discussion follows...

* Accumulating snow expected late tonight into Wed AM, with
  highest amounts south of the Pike

* Significant impact to Wed AM Rush hour possible, especially
  across parts of NE CT, Rhode Island and Southeast MA

Classic anafrontal wave develops later tonight as robust mid
level shortwave digs into the Great Lakes with SW flow aloft
across SNE. This will allow deeper moisture axis to set up
across the region with impressive jet dynamics as right
entrance region of 170-180kt upper jet moves across the region.
Initially, around and just after midnight, ptype will be rain
in the coastal plain with snow further in the interior. However,
rain will flip to snow from I-95 corridor to the south coast
from 06-09z and 09-12z for the Cape/Islands where a period of
sleet is possible during the transition.

Good synoptic scale forcing with some enhanced mesoscale
forcing as band of mid level frontogenesis develops. Pinpointing
the location of this banding potential is a challenge but
latest guidance suggests it will be mostly south of the Mass
Pike. Also, low level NW flow will attempt to bring in some low
level dry air, especially to the north of where any mesoscale
snow band sets up which may result in a sharp cutoff to the
north. But there is also some concern that the drier air will
limit duration of heavier snow. So the question is can robust
synoptic and mesoscale forcing make up for possible decreasing
moisture. We think there will be a brief window for a brief
period of moderate to heavy snow late tonight to about mid
morning, especially across RI and SE MA to Cape Cod. Timing is
not great and this would have a significant impact on the
morning commute.

Snowfall accum forecast is quite challenging for several
reasons. First, initial QPF as the rain changes to snow may be
wasted on melting, the exact location of a mesoscale snow band
is uncertain, and low level drier air may impact snowfall
intensity. The previous forecast accums still look reasonable
and will not make significant changes. Looking at 2 to 4 inches
from near the Mass Pike to the south coast, and 1 to 2 inches
to the north. But this will depend on where any banding sets up
and this could shift north or south of current forecast. The
worst case scenario would be a 4-6 inch snowfall which is a low
probability occurrence.

No changes to winter weather advisories. While some areas in the
advisory may not reach criteria, we felt the impact of snow
during the morning commute warrants the advisory. Snow will be
exiting the region from west to east during the morning followed
by increasing sunshine in the afternoon. Highs will be in the
30s.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
Highlights...
* Dry conditions and colder than normal temperatures on
  Wednesday night and Thursday

* Temperatures moderate on Friday as next weather system brings the
  potential for heavy rain & localized flooding late Friday into
  Saturday. Flooding risks may be exacerbated by snowmelt.

* Leftover rain/snow showers linger into early Sunday. Drying out
  and seasonably cold on Monday before next system arrives on
  Tuesday.

Details...

Wednesday night and Thursday...

As the arctic short wave departs, a large 1040mb high pressure will
shift east across the Ohio valley into our region. With strong cold
air advection and a fresh snowpack, overnight temperatures on
Wednesday will fall into the teens in interior MA and CT and low 20s
elsewhere away from the coast. The pressure gradient would keep
northwest winds blowing at 10 to 15 kts, which would mean wind
chills in the single digits in the interior and teens elsewhere.

On Thursday, despite mostly sunny skies, most locations will see sub-
freezing highs due to continued cold air advection. The albedo
effect from the snowpack and low sun angle will also help offset
radiational heating. Factoring in the northwest winds at 5 to 10
kts, it will feel like in the 20s area wide during the day on
Thursday.

By Thursday evening, the center of the high pressure moves offshore
into the Canadian Maritimes. Winds become light and variable before
switching to the south and southeast after midnight. Clouds will
start to increase ahead of the next system.

Friday through Saturday night...

***Heavy Rain and Flood Potential***

A potent low pressure system will move north on Friday. A
southeasterly flow should see high temperatures moderate to the mid
30s in the interior and mid 40s near the coast. Shower chances
increase during the day ahead of the main system. Enough shallow
cold air should linger in interior MA and CT for the precipitation
to start off as snow or mixed precipitation. Surface maps also have
signatures of cold air drainage from the northeast so there may be a
few hours of light snow or mixed precipitation. But as warmer air
lifts north, any precipitation should change over to plain rain
showers by Friday afternoon.

By Friday night, the 500mb long wave trough starts digging out of
the midwest into the southeast states. This will set up a strong
southwest mid level wind flow allowing the deep layer moisture to
work into the northeast late Friday into early Saturday morning,
with PWATs up to 2-3 standard deviations above normal and pockets of
3-4 standard deviations along the coast. A model blend shows 2 to
2.5 inches of QPF across the area while WPC is less bullish, with 1
to 1.5 inches of QPF for Western MA and 1.5 to 2 inches of QPF
elsewhere. Heavy rainfall rates on Saturday morning and afternoon
could lead to localized flooding. High temperatures on Saturday look
to be in the mid to upper 40s across Western MA/CT and mid 50s
elsewhere.

An issue of concern is the flooding potential. According to co-op
observers' reports this morning, we have about a 6-8 inch snow depth
with just under 2 inches snow water equivalent in Northwest MA. That
gives us about 30% snow density, which indicates a ripe snowpack. So
the combination of snowmelt runoff and heavy rain may result in
localized urban and poor drainage flooding. Will continue to monitor
river levels for any rises.

Sunday through Tuesday...

Low pressure will shift northeast into Maine and the Maritimes by
Sunday morning, though light rain may linger especially near and N
of the Mass Pike. Another cold front may wrap around the departing
low late Sunday or Sunday night. May see the rain mix with or change
to snow, but looks like the best chance may occur across the east
slopes of the Berkshires and possibly the northern Worcester hills
during the afternoon before tapering off.

Another cold front will sweep across the region by Monday morning,
bringing gusty northwest winds and colder air across the region.
Expect highs on Monday to be in the 30s and 40s. Another low
pressure system looks to impact the area by early Tuesday. With the
cold air in place, it should start off as snow before changing to
mixed precipitation or rain away from the interior. But since we are
still a week away, confidence is extremely low in any specific
solution.

&&

.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
Forecaster Confidence Levels...

Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.

Short Term /through Wednesday/...

00Z TAF Update:

Tonight and Wednesday...Moderate confidence.
Winds shift to the NW tonight behind a strong cold front. Cigs
may temporarily lift to VFR in the evening across portions of
the interior. Still looking at change from rain to a period of
snow 00-06z interior and 06-10z along the coast. MVFR/IFR
conditions, with a period of LIFR and brief moderate/heavy snow
possible across RI and SE MA late tonight and Wed morning.
Conditions quickly improve to VFR with clearing skies from NW to
SE late morning into the afternoon.

KBOS Terminal...Moderate confidence in TAF. Rain changing to
snow around 06z and ending 13-14z. Slushy 1-2 inches possible
with an impact to the morning push.

KBDL Terminal...Moderate confidence in TAF. Rain changing to
snow 04-06z ending 12-13z. 1-2 inches possible with
an impact to the morning push.

Outlook /Wednesday Night through Sunday/...

Wednesday Night through Thursday: VFR. Windy with local gusts
up to 30 kt.

Thursday Night: VFR.

Friday: MVFR/IFR conditions possible. Breezy. Chance SHRA,
chance SHSN.

Friday Night: Mainly IFR, with areas MVFR possible. Breezy.
SHRA.

Saturday: Mainly MVFR, with areas IFR possible. Windy with
local gusts up to 30 kt. Chance SHRA.

Saturday Night: MVFR/IFR conditions possible. Breezy. Slight
chance SHRA.

Sunday: Mainly VFR, with areas MVFR possible. Windy with local
gusts up to 30 kt. Slight chance SHRA.

&&

.MARINE...
Short Term /through Wednesday/...High confidence.

Tonight...
Winds shift to NW tonight with a period of G25 kt, especially
over the eastern waters. Hazardous seas persist over outer
waters. Vsbys reduced in showers and fog, changing to snow late
tonight.

Wednesday...
Diminishing NW winds and seas but seas remaining AOA 5 ft over
the outer waters. Improving vsbys as rain/snow exit.

Outlook /Wednesday Night through Sunday/...

Wednesday Night: Moderate risk for Small Craft Advisory winds
with gusts up to 30 kt. Areas of rough seas.

Thursday: Low risk for Small Craft Advisory winds with areas of
gusts up to 30 kt. Local rough seas.

Thursday Night: Winds less than 25 kt.

Friday: Winds less than 25 kt. Areas of seas approaching 5 ft.
Chance of rain showers. Local visibility 1 to 3 nm.

Friday Night: Moderate risk for Small Craft Advisory winds with
gusts up to 25 kt. Areas of rough seas. Rain showers.

Saturday: Moderate risk for Small Craft Advisory winds with
gusts up to 30 kt. Rough seas up to 12 ft. Chance of rain
showers.

Saturday Night: Low risk for Small Craft Advisory winds with
gusts up to 30 kt. Rough seas up to 12 ft. Chance of rain
showers. Local visibility 1 to 3 nm.

Sunday: Moderate risk for Small Craft Advisory winds with gusts
up to 30 kt. Rough seas up to 12 ft. Slight chance of rain
showers.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...Winter Weather Advisory until noon EST Wednesday for
     CTZ002>004.
MA...Winter Weather Advisory until noon EST Wednesday for MAZ012-
     013-015>022.
RI...Winter Weather Advisory until noon EST Wednesday for
     RIZ001>007.
MARINE...Small Craft Advisory until 7 PM EST Wednesday for ANZ235-237-
     250-254>256.

&&

SYNOPSIS...KJC/Chai
NEAR TERM...Frank
SHORT TERM...KJC
LONG TERM...Chai
AVIATION...KJC/Loconto/Chai
MARINE...KJC/Loconto/Chai

Hazardous Weather Outlook
National Weather Service Boston/Norton MA
519 PM EST Tue Dec 10 2019

ANZ233-MAZ002>011-014-023-024-026-RIZ008-112230-
Vineyard Sound-Western Franklin MA-Eastern Franklin MA-
Northern Worcester MA-Central Middlesex MA-Western Essex MA-
Eastern Essex MA-Western Hampshire MA-Western Hampden MA-
Eastern Hampshire MA-Eastern Hampden MA-Southeast Middlesex MA-
Dukes MA-Nantucket MA-Northern Middlesex MA-Block Island RI-
519 PM EST Tue Dec 10 2019

This Hazardous Weather Outlook is for central Massachusetts,
eastern Massachusetts, northeastern Massachusetts, southeastern
Massachusetts, western Massachusetts, Massachusetts coastal waters
and southern Rhode Island.

.DAY ONE...Tonight.

Light rain will change over the snow from north to south overnight
tonight, with light accumulations toward daybreak mainly on untreated
surfaces.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

An area of snow will bring light accumulations across central and
northern areas as well as the islands Wednesday.

In addition, the combination of melting snow and another round of
rainfall Saturday, falling heavy at times, could produce nuisance
minor flooding and result in rises on rivers and streams.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

CTZ002>004-MAZ012-013-015>022-RIZ001>007-112230-
Hartford CT-Tolland CT-Windham CT-Southern Worcester MA-
Western Norfolk MA-Suffolk MA-Eastern Norfolk MA-Northern Bristol MA-
Western Plymouth MA-Eastern Plymouth MA-Southern Bristol MA-
Southern Plymouth MA-Barnstable MA-Northwest Providence RI-
Southeast Providence RI-Western Kent RI-Eastern Kent RI-Bristol RI-
Washington RI-Newport RI-
519 PM EST Tue Dec 10 2019

...WINTER WEATHER ADVISORY IN EFFECT FROM 10 PM THIS EVENING TO NOON
EST WEDNESDAY...

This Hazardous Weather Outlook is for northern Connecticut, central
Massachusetts, eastern Massachusetts, southeastern Massachusetts,
northern Rhode Island and southern Rhode Island.

.DAY ONE...Tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Winter Weather Advisory.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Winter Weather Advisory.

In addition, the combination of melting snow and another round of
rainfall Saturday, some heavy at times, could result in rises on
rivers and streams and produce nuisance minor flooding.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

ANZ230>232-234>237-250-251-254>256-112230-
Boston Harbor-Cape Cod Bay-Nantucket Sound-Buzzards Bay-
Rhode Island Sound-Narragansett Bay-Block Island Sound-
Coastal waters east of Ipswich Bay and the Stellwagen Bank National
Marine Sanctuary-Massachusetts Bay and Ipswich Bay-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
Coastal Waters extending out to 25 nm South of Marthas Vineyard and
Nantucket-
Coastal Waters from Montauk NY to Marthas Vineyard extending out to
20 nm South of Block Island-
519 PM EST Tue Dec 10 2019

This Hazardous Weather Outlook is for Massachusetts coastal waters
and Rhode Island coastal waters.

.DAY ONE...Tonight.

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

For the latest updates...please visit our webpage at
www.weather.gov/boston

You can follow us on Facebook at
www.facebook.com/us.nationalweatherservice.boston.gov

You can follow us on Twitter at
@NWSBoston

Special Weather Statement
National Weather Service Boston/Norton MA
919 PM EST Tue Dec 10 2019

MAZ002>011-014-026-110930-
Western Franklin MA-Eastern Franklin MA-Northern Worcester MA-
Central Middlesex MA-Western Essex MA-Eastern Essex MA-
Western Hampshire MA-Western Hampden MA-Eastern Hampshire MA-
Eastern Hampden MA-Southeast Middlesex MA-Northern Middlesex MA-
Including the cities of Charlemont, Greenfield, Orange, Barre,
Fitchburg, Framingham, Lowell, Lawrence, Gloucester,
Chesterfield, Blandford, Amherst, Northampton, Springfield,
Cambridge, and Ayer
919 PM EST Tue Dec 10 2019

...RAIN TRANSITIONS TO A PERIOD OF SNOW OVERNIGHT MAY RESULT IN
ROADS BECOMING SNOW COVERED AND SLIPPERY FOR THE MORNING COMMUTE...

Rain is already transitioning to snow across the Berkshires and
this process will occur over the next few hours across the rest of
western and central Massachusetts. The rain across northeast
Massachusetts should change to snow by 2 or 3 AM.

A coating to 2 inches of snow accumulation is possible through
daybreak. The higher of the amounts are more likely in the
Worcester Hills and portions of northeast Massachusetts, where
some 3 inch amounts are possible. Untreated roads may become snow
covered and slippery for the morning commute. This is especially
true across the Worcester Hills and northeast Massachusetts, where
it may still be snowing for the first part of the Wednesday
morning commute.

Motorists planning travel overnight into early Wednesday morning,
should be prepared for roads becoming snow covered and slippery.
Allow extra time for the morning commute, especially in the
Worcester Hills into northeast Massachusetts.

Frank