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Area forecast discussion 
National Weather Service Taunton Massachusetts
409 am EDT Fri Oct 28 2016

strengthening low pressure over eastern Massachusetts early this morning will
intensify as it moves slowly offshore today. This will result in a
drying trend but windy conditions as well. Mild and less wind
Saturday as a ridge of high pressure moves across the area. Low
pressure approaches Sunday with a period of rain possible in the
afternoon and evening. High pressure delivers dry but cooler weather
Monday. Temperatures moderate Tue as the high moves offshore with
Wednesday likely being the mildest day next week. A dry cold front
Ushers in a cooler airmass late next week.


Near term /until 6 am this morning/...
11 PM update...

First band of heavier rainfall has pushed off of east coastal mass
at 03z, but one more area of rainfall across S central mass into
Connecticut will shift east across central and eastern areas through
3-4 am. Temperatures have hovered around freezing across north central
and northwest mass through this evening, so light snow and sleet has been
reported there. However, expect this to finally change over to
rain as east-southeast winds pick up and scour out the colder air.

Noting a few thunderstorms that have developed S of Long Island at
03z, but as better elevated instability with and ahead of dry slot
behind the second area of rain moves in, will see a few more
storms form mainly over the coastal waters.

Still expect period of gusty southeast-S winds that will mix down with
any convection or heavier rainfall, so have continued the Wind
Advisory across east and southeast mass into east Rhode Island.

Have updated overnight forecast incorporate this evening's
conditions, as well as adjusted temps/dewpts/winds. Near term
timing has also been adjusted to reflect current conditions.

Previous discussion...

Wind potential...low level jet increases as it moves across Rhode
Island and southeast Massachusetts. This coupled with the rain and
potential convection will result in strong, gusty winds mixing down
to the surface. Wind Advisory criteria is expected on the cape and
islands. Think there is a decent chance that higher winds will mix
down in the convection elsewhere along the east and S coasts of Massachusetts and
Rhode Island. In addition, temperatures rising in the warm sector will allow
for better mixing through the coastal plain. Kept the Wind Advisory
as is for the overnight period.

Temperatures...with the warm sector moving over portions of Rhode Island and
southeast Massachusetts overnight, expect temperatures to climb into the 50s if not
near 60 on the South Coast. Low temperatures will be in the mid 30s
in western Massachusetts to the mid 40s in the coastal plain before we warm


Short term /6 am this morning through 6 PM Saturday/...
will see the rain coming to an end from west to east early Friday
morning. Much of Friday should be dry with the shortwave and
associated surface low moving out to the Gulf of Maine during the
day. Attention will then be turned to the northwesterly winds as
the surface low deepens just offshore. Expect near advisory
criteria on the cape and islands at times during the day. Elsewhere
along the coast it should be just below, in the 25 to 35 kt range.
Further inland, gusts to 20 to 25 kts are expected.

High temperatures will be reached early on in the day with the
warmest temperatures on the coastal plain where the warm sector
moved over during the overnight. Elsewhere, highs in the upper 40s
to around 50 are expected.


Long term /Saturday night through Thursday/...

Updated 405 am...


* seasonable much of the time...coolest Mon and warmest Wed
* chance of rain sun aftn/evening...otherwise mainly dry

Sat night and Sunday...

Weak cold front moves across the area. Deep layer moisture and lift
are other than a spot shower mainly dry weather
prevails Sat night. Warm air advection in prefrontal airmass yields mild conditions
Sat night with mins only dropping into the 45-50 deg range. Normal
low temps should be in the upper 30s to low 40s range. Breezy Sat
evening with southwest winds 15-25 mph...strongest winds along the
coast and high terrain.

Sunday...still amplitude differences among the models regarding
northern stream short wave inducing a wave of low pres over
PA/NJ/NYC area on the frontal boundary passing our region Sat night.
However good agreement on the timing with all guid including the 00z
gefs and 00z ec on rain holding off until Sun afternoon or evening
across most of CT/Rhode Island and Massachusetts. Remaining mild Sunday as cooler air
lags way to the north of the frontal boundary draped along our
South Coast.

Next week...

Monday...northern stream short wave and associated frontal wave exit
east of our longitude Sun night and replaced by modest cold air advection Monday
along with 1026 mb high over the eastern Great Lakes building east
into New England. So dry weather Monday but cooler with highs 50-
55...upper 40s higher terrain. Normal high still about 55-60. A
chilly north wind in the morning then diminishing in the afternoon
as high pres crest over the region.

Tuesday...chilly start to the day with high pres over the
area...however high pres drifts offshore with return flow for the
afternoon. Thus temps will moderate to seasonal levels Tue aftn with
highs 55-60. Low risk of a spot shower Tue night with weak front
approaching from the northwest. Mins Mon ngt/Tue am were derived
from the colder MOS guid.

Wednesday...could be the pick of the week with warm air advection ahead of
approaching weak cold front. After a mild Tue ngt with mins only 45-
50...highs Wed aftn could make a run at 70! Golf? Other than a spot
shower a dry frontal passage is likely as models suggest deep layer
moisture and lift lacking.

Thursday...a cooling trend likely develops as both eps and gefs
ensembles indicate northern stream lowering heights across the
northeast states.


Aviation /08z Friday through Tuesday/...
forecaster confidence levels.

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

Short term /through Saturday/...

Overnight...high confidence in trends, lower on timing. Rain will
continue through the night with periods of heavy rain possible.
Expect a mix of MVFR-IFR conditions in rain/patchy fog. On the
coastal plain, the south coasts of Rhode Island/MA, and the cape and
islands; east-southeast winds will gust up to 35 to 40 kts at times.
Elsewhere, winds will be a bit lighter, gusting up to 25 kt along
the East Coast, and below 20 kt across the interior.

Friday...high confidence in trends, lower on timing. Will see
patches of rain coming to an end from SW-NE, with NE Massachusetts the last
to dry out. Conditions will improve to MVFR and even VFR in some
places. West-northwest winds will remain gusty through the day,
particularly on the cape and islands where gusts up to 40 kts are

Kbos taf...high confidence in trends, lower confidence in timing.

Kbdl taf...high confidence in trends, lower confidence in timing.

Outlook /Saturday night through Tuesday/...

Updated 405 am...

Saturday night - Sunday...moderate confidence.

VFR likely Saturday along with dry weather. Then MVFR possible
Sunday afternoon and evening in a period of rain.

Monday-Tuesday...high confidence.

VFR, with mainly dry weather.


forecaster confidence levels.

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

Short term /through Saturday/...high confidence.

Southeasterly gale force wind gusts are expected into Friday,
eventually switching over to the northwest. Gale warnings are up
for all waters and may need to be extended farther into Friday
evening/night. Waves increase to 8 to 10 feet on the outer waters.
Periods of heavy rain and fog may limit visibilities at times

Outlook /Saturday night through Tuesday/...

Updated 405 am...

Saturday night - Sunday...moderate confidence.

Southwest winds 15 to 20 kt with gusts up to 25 kt possible Sat
night. Mainly dry weather and good vsby. Then Sunday light west-northwest as
weak cold front boundary sags south across the waters. Then winds
become east-northeast 15 to 20 kt as wave of low pres tracks along the front
from west to east. Vsby will lower to 1-3 miles in rain Sunday
afternoon and evening...then improving overnight.

Monday-Tuesday...high confidence.

North winds Monday 15-20 kt with gusts up to 25 kt possible. Could
be a few ocean effect rain showers. North winds will increase seas
across the eastern Massachusetts waters. Diminishing winds Mon ngt into Tue
morning as high pres crest over the region. Then winds becoming
south late Tue.


Box watches/warnings/advisories...
Massachusetts...Wind Advisory until 10 am EDT this morning for maz007-014>024.
Rhode Island...Wind Advisory until 5 am EDT early this morning for riz007-008.
Marine...Gale Warning until 6 PM EDT this evening for anz231>234-250-
Gale Warning until 9 am EDT this morning for anz230-235-237.
Gale Warning until 5 am EDT early this morning for anz236.
Gale Warning until 2 PM EDT this afternoon for anz256.


near term...Belk/evt
short term...rlg
long term...nocera

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