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Area forecast discussion 
National Weather Service Taunton Massachusetts
721 PM EST Wednesday Nov 25 2015

high pressure remains an influence across New England through the
end of the week during which time temperatures gradually warm as
the high moves offshore. A cold front from southern Quebec and
Ontario will cross the region late Friday night and Saturday.
High pressure will bring dry weather early next week. Another
storm may affect New England late Tuesday into Wednesday.


Near term /until 6 am Thursday morning/...

645 PM update...

Band of low clouds working in off the ocean on S-southeast winds across
S CT...Rhode Island along with patchy clouds forming along S coastal Massachusetts as
seen on latest infrared 3.9u satellite imagery. This band extends
offshore and expanding as it heads toward the coast. Ceilings at
3500-4500 feet at 23z. Previous forecaster noted this low level
moisture is trapped below subsidence should
continue to push onshore overnight. For now...the clouds are
tending to dissipate as they move onshore due to wide temperature/dewpt
spreads temperatures fall back and continued light onshore wind
flow...should become more broken-overcast through the overnight and may

Other than clouds moving inland and updating this trend...
remainder of forecast was in pretty good shape. Updated to bring
conditions current.

Previous discussion...
rather strong high pressure nearing 1050 mb moves offshore tonight
with low level southeast flow in place across southern New England. Models are rather
bullish on moistening below 850 mb expanding across southern New England with
soundings showing this moisture trapped below a subsidence
inversion. This will result in areas of SC developing during
tonight but still some uncertainty with how expansive clouds
will be which will have an impact on min temperatures. Initially it is
expected the clouds will be confined to west new eng then spreading
east overnight. Can not completely rule out patchy drizzle in the
west but confidence is low.

Min temperatures will be a challenge tonight due to uncertainty in cloud
cover and could see a wide range in temperatures. Expect temperatures to fall
sharply early this evening with mostly clear skies and light
winds...then temperatures may level off if clouds develop. Expect lows
down into the 20s in portions of CT valley and interior east Massachusetts with
30s elsewhere.


Short term /6 am Thursday morning through Thursday night/...
strong high pressure remains offshore with surface ridging extending to
the west along the S coast and middle Atlantic region. The column is
mostly dry...but the challenge will be determining extent of cloud
cover as low level moisture below 850 mb persists...most prevalent
in west new eng. Expect at least broken SC with partial sunshine at
times during Thursday...with most sun across southeast coastal new eng where
low level dry air is more pronounced. Increasing low level S/SW
flow will result in some gusts to 20+ miles per hour developing. The SW winds
will bring milder air into southern New England with temperatures reaching the middle/upper
50s...cooler higher elevations.

Thursday night...
surface ridging remains east of new eng with SW flow and low level moisture
below subsidence inversion. Expect pt-mostly cloudy skies with milder
temperatures than tonight due to higher dewpoints and more clouds.
Forecast lows will be upper 30s to lower 40s.


Long term /Friday through Wednesday/...
* high pressure pushes east on Friday
* cold front crosses the region late Friday night and Saturday
* dry and near seasonable conditions early next week
* low pressure may approach late Tuesday and Wednesday

Overview and model preferences...

Medium range model suite continues to signal western U.S. Rex
blocking into late this weekend before starting to slowly
migrating east early next week. Split 500 mb flow will remain in place
for a good chunk of this period as the cutoff low shifts into the
upper plains early next week. This will respond with a more northwest
flow aloft before ridging ahead of cutoff system moves in.
However... still timing issues as the upper system moves across
the upper plains. Wide model solution variance continues beyond
Monday with the surface feature timing...leading to very low
confidence with approach of next system for sometime Tuesday and/or

Leaned toward a blend of available guidance through Monday...
which showed good continuity and consistency to the previous
forecast. Beyond Monday...transitioned over to the ensembles where
remained fairly good but with such wide model solution spread
between the GFS and European model (ecmwf) on their operational runs...have low
confidence for the approaching system late in the period.


Friday...high pressure ridge lying NE-SW from Nova Scotia to the southeast
U.S. Will slowly shift southeast during the day. SW wind flow increases
as a cold front approaches out of southern Quebec/Ontario along
with increasing 850 mb jet. Expect clouds to increase late Friday/Friday
night as front approaches. 850 mb temperatures also increase during the
afternoon...up to +9c to +10c late in the day. With a good amount
of sun prior to the increasing clouds...expect temperatures to rise to
the middle 50s across the higher inland terrain to the lower 60s
along the coastal plain and lower CT valley. Not quite mild enough
for record highs /at this point/...but will be up to 15 degrees
above seasonal normals for late November.

Friday cold front slowly moves into northern
New England...looks like leading edge will reach into north Massachusetts around
midnight or so. Models still signal decent low level convergence
ahead of the front even though best dynamics remain north of the
region. Will see chance probability of precipitation moving across...but not a whole lot
of precipitation.

Did note that the timing on the operational runs of the 12z model
suite seem to slow the frontal passage a bit during Saturday. Line
of showers should push off the S coast by midday...moving offshore
by nightfall. Back edge of clouds will move to near the Mass Pike
late. Temperatures will rise only a few degrees during the day with cloud
cover and scattered showers...ranging from the middle and upper 40s well
inland to lower 50s along the S coast.

Saturday night-Monday...skies will average partly cloudy Sat
night but it will be colder as temperatures fall back to the 20s away
from the coast and the Lower-Middle 30s along the immediate

Another ridge of high pressure elongates east-west from the northern
Mississippi Valley across the New England. West-northwest flow at 500 mb sets
up...which will keep the passed front well S of the region.
So...expect partly to mostly sunny conditions both Sunday and
Monday. High temperatures will be near or slightly below normal.

Tuesday-Wednesday...breakdown of western upper level blocking
pattern will slowly migrate east during this timeframe. As mentioned
above...timing is very much in question with approach of next
system. Did slow down timing of approach of chance probability of precipitation until late
Tuesday into the CT valley/east slopes of the Berkshires for now. Does
look like best shot of precipitation will occur Tuesday night into Wednesday at
this point.


Aviation /00z Thursday through Monday/...
forecaster confidence levels...

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

Short term /through Thursday night/...

Tonight...moderate confidence for overall forecast...lower on
exact locations. Mainly VFR. Scattered-broken ceilings from 3500-4500 feet
moving onshore across north CT/Rhode Island and developing along S coastal Massachusetts.
May see patchy fog with local MVFR-IFR visibilities after midnight.

Thursday...mainly VFR. Areas of broken ceilings 3-4k feet...but lower
confidence in exact location. Light winds tonight...with S wind
gusts to 20 knots developing Thursday.

Thursday night...moderate confidence. Areas of MVFR ceilings
developing in west new eng with low probability for IFR. Likely remaining
VFR in the east.

Kbos terminal...high confidence in VFR.

Kbdl terminal...areas of MVFR ceilings may develop tonight...but
confidence not high.

Outlook /Friday through Monday/.....Moderate confidence.

Friday...patchy fog early with MVFR to local IFR visibilities should
dissipate by middle morning. However...may see MVFR-IFR across west
Massachusetts/north central CT through midday with S wind flow in place. Some
MVFR ceilings/visibilities may linger on S coast with onshore winds. Mainly
VFR conditions elsewhere.

Friday night-Saturday...mainly VFR through around midnight.
Patchy fog may develop with local MVFR-IFR visibilities. May also see
local MVFR ceilings in scattered showers overnight into Sat morning.
Generally VFR Sat afternoon/night.



forecaster confidence levels...

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

Short term /through Thursday night/... high confidence.

S-southeast winds slowly increase tonight into Thursday as surface high moves
offshore with increasing pressure gradient from the north. Expect gusts to
20 knots developing by Thursday morning. G25 knots likely across NE Massachusetts
coastal waters Thursday into Thursday evening where low level winds are
strongest and will issue Small Craft Advisory for these waters. Winds diminishing S
coastal waters Thursday night.

Outlook /Friday through Monday/...

Outlook /Friday through Monday/...

Friday...high confidence.
S-SW winds increase as high pressure moves offshore. Gusts may reach
20- knots on the eastern outer waters...but seas build to 5-6 feet
late in the day through Friday night. Small crafts will likely be

Friday night-Saturday...moderate to high confidence.
SW winds shift to west-northwest as the cold front passes late Friday
night/Sat. Gusts up to 20 knots through midday Sat. Seas on the
outer waters build up to 7 feet.

Saturday night-Sunday...moderate confidence.
Winds diminish as they veer to north Sat night as seas slowly
subside...with light winds and seas 4 feet or less on Sunday.

Monday...moderate confidence.
High pressure builds west of the winds shift to NE and
increase. Gusts up to 25 knots and seas building up 5-6 feet...highest
on the eastern outer waters. Small crafts likely needed for at
least portions of the waters.


record highs Friday 11/27...

Bos...72 in 1896
pvd...66 in 1946
bdl...64 in 1976
orh...66 in 1896

Record high mins Friday 11/27...

Bos...57 in 1896
pvd...51 in 1976
bdl...46 in 1927
orh...52 in 1896


Box watches/warnings/advisories...
Rhode Island...none.
Marine...Small Craft Advisory from 7 am Thursday to 1 am EST Friday for
Small Craft Advisory from 7 am to 7 PM EST Thursday for anz251.


near term...kjc/evt
short term...kjc
long term...evt

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