Area Forecast Discussion
Issued by NWS Boston, MA

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FXUS61 KBOX 230239
AFDBOX

Area Forecast Discussion
National Weather Service Taunton MA
1039 PM EDT Fri Sep 22 2017

.SYNOPSIS...
The remnants of Jose will continue to weaken overnight as it
very slowly drifts southeast, but the storm will still bring
a few showers to southeastern MA and RI. Low clouds will
gradually scour out from west to east during the day Saturday
and it will turn warm across interior southern New England.
Unseasonably warm weather is on tap Sunday into the middle of
next week, especially away from the coast.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...

We made adjustments to temperatures and winds at 9 and 10 pm
based on surface and buoy observations. Somewhat milder temps in
the CT Valley, but these will trend toward the expected min
temps overnight. North-northeast winds at Buzzards Bay and
Nantucket Sound still around 33-34 knots, so we nudged hourly
forecast winds across the South Coast up a few knots, but
maintaining the same overnight trend.

Still some showers over Southeast Mass and RI, so we stretched
the period of likely pops until after midnight, then diminishing
overnight as expected.

The rest of the forecast is the same. The remnants of Jose drift
southeast, but low level flow continues off the Gulf of Maine so
we expect clouds to linger overnight most areas...possibly
partial clearing overnight in Western Mass and the Hartford
County areas.

With diminishing wind in the west, min temps should range from
55-60. In the cloudier east, dew points are a little higher and
winds a smidge stronger, so min temps will be around 60.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/...
Saturday...

We can not rule out a few left over spot showers or perhaps a bit of
drizzle across the far southeast New England coast Saturday morning,
but regardless there will be an abundance of low clouds. Model cross
sections indicate drier low level air should allow for plenty of
sunshine across western MA/western CT by mid afternoon.  Given 850T
around +16C lower elevations in these areas should see afternoon
highs soar into the middle 80s. Meanwhile along and southeast of the
Boston to Providence corridor, low clouds will linger into mid
afternoon but most areas should see improvement by late
afternoon/early evening except for the Cape and Islands.  Given the
late recovery will go for late day highs in the middle to upper 70s
in the Boston to Providence corridor, but keep them around 70 for
the Cape and Islands.

Surf:

Lingering high seas from left over swell, opted to issue a high surf
advisory through Saturday on all ocean exposed south and east facing
beaches.  High surf and dangerous rip currents will be a concern,
particularly now that many beaches do not have lifeguards given that
the official summer beach season has ended.

&&

.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
Highlights...

* Return to summer warmth Sunday and Monday
* Showers possible by mid week
* Watching Maria, but latest NHC track keeps it offshore

Jose continues its slow dissipation through early next week, keeping
high surf and an elevated risk of rip currents on south coastal
beaches. Concern is for an increase in beachgoers this weekend, as
building upper ridge brings return to warmer conditions. Keep in
mind many area beaches are no longer staffed with lifeguards this
late in September!

Still expecting an anomalous ridge to develop over the Northeast
this weekend and early next week. Besides the return of summer-like
heat, including the possibility of a few 90 degree readings in the
Merrimack and Connecticut river valleys, we should also see a
prolonged period of dry weather.

Still expecting a backdoor cold front to move into our region from
the east Tuesday into Wednesday. While temperatures will be lower
than this weekend, still expecting above near to slightly above
normal temperatures. Cannot rule out scattered showers either, which
should be focused mainly across the eastern half of southern New
England.

This mid level ridge is also expected to play a role in delaying
the northward progress of Maria along the Eastern Seaboard. If Maria
is delayed long enough, there should be enough time for a mid level
trough and a surface cold front to push Maria out to sea. The track
or Maria should be close enough to bring another round of high surf
with a renewed threat of rip currents and beach erosion. It`s still
much to early to confidently say that will happen, since we need to
assess interaction with approaching Great Lakes trough/surface cold
front.

&&

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

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

Short Term /through Saturday/...

Overnight...Moderate confidence.

Mixed MVFR/VFR cloud bases in the Connecticut River Valley,
trending to IFR cigs in RI and Eastern Mass. Expect these to
linger through the night. Occasional lower vsbys in RI and
Eastern Mass in showers and fog, but the showers should taper
off overnight.

Saturday...High confidence in trends but low confidence in
timing. Marginal MVFR cigs across the interior should improve
to VFR to the northwest of the Boston to Providence corridor by
mid afternoon. MVFR-IFR Cigs in low clouds and fog patches
southeast of the Boston to Providence line will be slower to
improve, but should scour out towards 00z except for the
Cape and Islands.

KBOS TAF...Moderate confidence. IFR conditions much of the night
in drizzle and fog. Conditions improving Saturday.

KBDL TAF...Moderate confidence in TAF. Scattered to broken
ceilings will mainly be VFR but some periods of MVFR are
possible overnight.

Outlook /Saturday Night through Wednesday/...

Saturday Night...Moderate confidence. VFR west. IFR east.

Sunday and Monday...High confidence. Mainly VFR. Light winds
with seabreezes possible.

Tuesday and Wednesday...Moderate confidence. MVFR possible in
scattered showers, especially eastern MA. Otherwise, VFR.

&&

.MARINE...
Forecaster Confidence Levels...

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

Tonight...Moderate to high confidence.

The remnants of Jose will continue to weaken and drift southeast
overnight. Winds will diminish during this time. Observed winds
at Buzzards Bay and Nantucket Sound at 9-10 PM were 33-34 knots,
so we have extended Gales for all waters from Westerly to
Provincetown through 4 AM. Lighter winds in Cape Cod Bay and
east of Cape Ann, so Small Craft Advisory on those waters where
25 knot winds and 10 to 15 foot seas will gradually diminish.

Saturday...Moderate to high confidence.  Perhaps some left over
marginal gale force wind gusts across our southwest outer-waters
into mid morning.  Otherwise, wind gusts should continue to
gradually diminish from north to south but small craft gusts will
continue through the afternoon across our southern waters.  Seas
will also remain above small craft levels across the open waters
from left over swell.

Outlook /Saturday Night through Wednesday/...

Moderate confidence.

Light winds expected Sunday with local seabreezes as high pressure
remains over waters. A backdoor cold front is expected to move south
across waters Monday into Tuesday with light E/NE winds and
scattered showers.

Seas will gradually subside Sunday, and should finally drop below 5
ft on all waters except for the southern outer coastal waters.
Lingering swells from Jose, combined with increasing swells from
Maria, will likely lead to seas building over 5 ft again on waters
south and east of Nantucket by Monday or Tuesday.

&&

.TIDES/COASTAL FLOODING...
Diminishing seas and surge should preclude any additional pockets of
minor coastal flooding tonight, other than perhaps some very minor
splash over. However, additional beach erosion will still be a
concern into Saturday given high seas just offshore.

Swells from Maria may increase the surf and associated rip current
risk across our ocean-exposed south coast sometime during the first
half of next week, even though Maria may eventually recurve out
to sea before getting too close to New England.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...High Surf Advisory until 6 PM EDT Saturday for MAZ007-019-020-
     022>024.
RI...High Surf Advisory until 6 PM EDT Saturday for RIZ006>008.
MARINE...Gale Warning until 4 AM EDT Saturday for ANZ232>235-237-254.
     Small Craft Advisory until 10 AM EDT Saturday for ANZ230-231-
     236-250.
     Small Craft Advisory until 2 PM EDT Saturday for ANZ251.
     Gale Warning until 8 AM EDT Saturday for ANZ255-256.

&&

$$
SYNOPSIS...WTB/Belk/Frank
NEAR TERM...WTB/Belk/Frank
SHORT TERM...Frank
LONG TERM...Belk
AVIATION...WTB/Belk/Frank
MARINE...WTB/Belk/Frank
TIDES/COASTAL FLOODING...



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