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Area forecast discussion 
National Weather Service Taunton Massachusetts
204 am EDT Sat Oct 22 2016

additional showers are likely Saturday as the storm moves into
northern New England along with strong winds developing late
Saturday into Saturday night. Dry but cool and blustery conditions
Sunday into early next week.


Near term /until 6 am this morning/...
2 am update...
dry slot across southern New England early this morning with showers exiting east
coastal Massachusetts with another area of showers across New York state
assocd with the deep upper trof. Leading edge of these showers
will move into western New England toward daybreak, otherwise
mainly dry overnight with areas of fog. Temps quite mild in the
mid/upper 60s but cold front moving into the Berkshires with temps
around 50 behind the front. This cooler air will move into western
half new eng with temps falling through the 50s, but temps will
remain in the 60s in eastern new eng.


Short term /6 am this morning through 6 PM Sunday/...
notable diffluence aloft Saturday morning into early afternoon is
anticipated just ahead of rigorous negative tilt 500 mb trof axis
along with support of approaching left exit region of 110 to 120 kt
upper jet. Have gone with likely pops for a time Saturday in
anticipation of a band or two of heavy showers that will probably
rotate across CT, RI, and at least central/east central Massachusetts. Cold
pool aloft will also introduce an element of instability in the
afternoon in addition to a probably comma head wrap around. This is
inducement to keep pops elevated across western and central sections.

Expect warmest temperatures to be in the early morning hours with a
significant drop west to east during Saturday afternoon. This should
be especially noticeable over the higher terrain of western Massachusetts.

A surge of strong west to northwest winds is anticipated toward evening. It
will be first noted across the east slopes of the Berkshires. A Wind
Advisory will likely be needed with a start time possibly as early
as late Saturday afternoon. Per earlier coordination with
surrounding offices, this will probably be considered with a
subsequent shift after timing, extend, and magnitude become clearer.


Long term /Sunday night through Friday/...
* gusty winds expected Saturday night and Sunday
* temperatures drop below normal Sunday and continue dropping
through Tuesday/Wednesday time frame
* mainly dry weather through this time with a few areas of showers
possible on several days

Models are in good agreement through much of the long term,
particularly on the synoptic scale pattern. There are some
discrepancies, but these are largely on the smaller scale details as
well as timing. The pattern over the next week will be largely
dominated by upper level troughing in the northeastern U.S. This
will keep unsettled weather in the region for much of the time,
along with below normal temperatures.

Saturday night and Sunday...the main concern will be strong pressure
rises combined with a tight pressure gradient and decent cold air
advection that will be moving over southern New England. This will
result in breezy conditions beginning sometime Saturday afternoon
and continuing into Sunday. While winds will likely diminish a bit
during the overnight period due to the loss of sunshine and a
decline in mixing, the pressure rises and cold air advection will
act to continue mixing and gusty winds will continue. Wind Advisory
criteria may be reached Saturday evening and again on Sunday morning
but confidence is low in which areas and how frequently gusts may
exceed criteria, so have opted to hold off on a Wind Advisory at
this time. Temperatures will be seasonable through this period,
though The Drop in temperature from today added to the winds will
make it feel much cooler.

Monday through Wednesday...the upper level trough slowly moves
offshore and low pressure moves into the Maritimes. Temperatures
continue to fall with Tuesday and Wednesday likely the coldest of
this fall so far. A shortwave moves through the upper level flow on
Monday, possibly bringing a few showers to the region. High
pressure starts building into southern New England Tuesday and
Wednesday. Temperatures will be cool enough these days to possibly
induce some ocean effect clouds and showers on the cape and islands.

Thursday and Friday...a bit more uncertain with the timing here. The
GFS is a bit slower with the progression of the upper level pattern
than the European model (ecmwf). Shortwave ridging will move over southern New
England either Wednesday or Thursday before another shortwave trough
moves through. This trough may bring another chance for some
showers either late Thursday or Friday. Temperatures rebound a bit,
climbing back to normal or even a few degrees above normal.


Aviation /06z Saturday through Wednesday/...
forecaster confidence levels.

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

Short term /through Sunday/...

Through 12z...widespread IFR/LIFR cigs with areas of fog. Showers
may reach CT valley by 12z.

Today...moderate confidence. Improving cigs to MVFR through the
morning with improving vsbys. Numerous showers, some briefly
heavy, will move across southern New England during the morning into the afternoon
then become more focused across western Massachusetts and CT late afternoon.
Mainly MVFR cigs this afternoon with brief lower vsbys in heavier
showers. Low prob of an isold T-storm. Increasing west winds
mid/late afternoon with gusts 25-35 kt developing, especially
south of the Mass Pike.

Tonight...high confidence. MVFR cigs improving to VFR. Sct showers
continuing, mainly western new eng and focused over higher
terrain. West wind gusts to 35 kt.

Sunday...high confidence. VFR cigs clearing in the afternoon. West
wind gusts 30-40 kt, strongest higher terrain.

Kbos taf...high confidence in trends but lower confidence in

Kbdl taf...high confidence in trends but lower confidence in

Outlook /Sunday night through Wednesday/...

Monday through Wednesday...moderate confidence. Mainly VFR. Low
confidence in MVFR/IFR conditions developing on the cape and islands
in ocean effect clouds and rain showers Tuesday and Wednesday.


forecaster confidence levels.

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

Short term /through Sunday/...high confidence.

Near term issue will be areas of fog including pockets of dense fog.
There could also be some brief gusty winds in vicinity of showers
this evening but in general below Small Craft Advisory criteria. For
Saturday, there will be increasing SW winds during the early/mid
afternoon becoming west during late afternoon, and a Gale Warning is
posted for all waters.

Outlook /Sunday night through Wednesday/...

Saturday night and Sunday...high confidence. Westerly gale force
winds will continue through this period with a tight pressure
gradient between the departing low pressure system and building high
pressure in the Great Lakes. Westerly winds will shift to the
northwest on Sunday. Gale warnings have been extended for all waters
through Sunday.

Sunday night and Monday...high confidence. Small Craft Advisory
conditions continue though both winds and seas will diminish
gradually through the period as the pressure gradient slackens.

Tuesday and Wednesday...moderate confidence. Marginal small craft
conditions continue, particularly on the outer waters Tuesday and
Tuesday night. Winds and seas will be diminishing through this
period as high pressure builds over the waters.


Box watches/warnings/advisories...
Rhode Island...none.
Marine...Gale Warning from noon today to 6 PM EDT Sunday for anz231>235-
Gale Warning from 2 PM this afternoon to 6 PM EDT Sunday for


near term...kjc
short term...Thompson
long term...rlg

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