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000 
FXUS61 KBOX 221503
AFDBOX

Area Forecast Discussion
National Weather Service Taunton MA
1103 AM EDT Fri Sep 22 2017

.SYNOPSIS...
Jose southeast of Nantucket will slowly drift back to the southwest 
the next few days. This will maintain strong winds, rain and rough 
seas today, which then diminish. Clearing skies will move in 
from the west tonight and Saturday. Warmer weather arrives 
Sunday and Monday, before a backdoor front brings cooler weather
and possibly a few showers by midweek.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...

11 am update...

***Tropical Storm conditions across the far southeast New
 England coast with bands of showers with brief heavy rain will
 continue through the afternoon***

Jose continues to gradually weaken as it very slowly meanders
west about 120 miles southeast of Nantucket. However, it 
continues to bring Tropical Storm conditions to the far 
southeast New England coast and will continue headlines through 
the afternoon. Have also extended the wind advisory through 
early evening just northwest of that region. North to northeast 
wind gusts of 35 to 50 mph anticipated across much of southeast 
New England through the afternoon.

Bands of showers some containing locally heavy rain will 
continue to impact southeast MA and through the afternoon. Areas
of lighter showers and drizzle will also impact northeast MA 
and RI. Temperatures across parts of southeast MA may struggle
to break 60.

Meanwhile, despite considerable cloudiness in western MA and
northern CT there will be periods of partial sunshine. This
should allow high temps to reach into the middle 70s and winds
will be gusty.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
Jose continues to weaken while not moving out of the vicinity. So we 
expect north-northeast winds tonight and Saturday but with speeds 
diminishing to 5-15 mph inland and 15-30 mph on the Islands. Clouds 
linger over Eastern Mass and especially SE Mass until midday 
Saturday, but with a west to east clearing trend farther west. 

Lingering chance pops in RI and Eastern Mass tonight, but the chance 
dissipates Saturday morning as Jose further weakens.

Dew points 55 to 60 will allow min temps similar to that where the 
winds diminish inland, a little milder along the coast due to clouds 
and wind. Temps aloft around 15-16C will support max temps Saturday 
in the mid 80s. Southeast of the I-95 corridor the clouds and ocean 
influence should hold max temps in the upper 60s and 70s.

&&

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

 * Return to summer warmth Sun/Mon
 * 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 elevated risk of rip currents on south
coastal beaches. Concern is for an increase in beach-goers 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!

850 mb temperatures warm significantly, to nearly 20C Sun/Mon,
which translates to highs well into 80s across interior. It's
even possible we see a 90-degree reading in CT Valley Mon (BDL).
It's also not out of question parts of CT Valley experience
late-season heat wave, though highs should fall just short of 90
both Sun and Tue. 

Warmth won't last too long as backdoor front should drop south
across region Tue and Wed, bringing somewhat cooler (seasonable)
E/NE flow as well as scattered showers.

Later next week, we still need to monitor track of Maria. Latest
forecast is for it to pass offshore, but close enough to bring
another round of high surf with 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 /14Z 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/...

Today...Moderate to high confidence.

Low end MVFR to IFR conditions persist across eastern MA and RI
in some showers and drizzle. Lower conditions in southeast New 
England where bands of heavy showers will impact the region
through the afternoon. NNE wind gusts of 35 to 40 knots across
the southeast New England coast and a bit higher at times in
Nantucket. Northerly wind gusts of 20 to 30 knots elsewhere.

Meanwhile across most of western and central MA/northern CT 
expect high end MVFR to VFR Cigs despite a broken deck of 
clouds.

Tonight and Saturday...

MVFR cigs linger across Eastern Mass and RI tonight, then lift to 
VFR Saturday. Winds will diminish through the period, with gusts 20-
30 knots mainly along the South Coast.

KBOS TAF...Moderate confidence. Low end MVFR to perhaps some
periods of IFR conditions in showers and areas of drizzle today.
NNE wind gusts between 30 and 35 knots. 

KBDL TAF...High confidence in TAF. Broken ceilings mainly VFR
but some periods of MVFR are possible.

Outlook /Saturday Night through Tuesday/...

High confidence.

Sun and Mon...
VFR. Light winds with sea breezes possible.

Tue...
MVFR possible in scattered showers, especially eastern MA.

&&

.MARINE...
Forecaster Confidence Levels...

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

Today...

Jose continues to very slowly drift west, but well south of the
waters. Still expect winds from the north-northeast, gusting 35
to 45 knots on the southern waters and 30 to 35 knots in the 
east. Seas will remain rough at 10-15 feet over the open ocean
waters. Showers continue, especially over the southern and 
southeast waters.

Tonight and Saturday...

Gusty north winds will diminish tonight and Saturday. Winds above 25 
knots will linger on the southern and southeast waters Saturday. 
Seas will also diminish through the period, but with 5 foot seas 
lingering on the outer waters Saturday.

Outlook /Saturday Night through Tuesday/...

Moderate confidence.

Light winds expected Sun with local sea breezes as high pressure
remains over waters. Backdoor cold front is expected to drop S 
across waters Mon into Tue with light E/NE winds and scattered
showers.

Seas will gradually subside Sun and should finally drop below 5
ft on outer waters. Lingering swells from Jose, combined with 
increasing swells from Maria may lead to seas building over 5 ft
again on waters S and E of Nantucket by Mon or Tue.

&&

.TIDES/COASTAL FLOODING...
Another round of minor coastal flooding is expected with this
afternoon's high tide on Nantucket with expected 1 ft storm
surge. Along Plymouth County coast, based on latest data we
opted to issue a coastal flood advisory for pockets of minor
coastal flooding at the mid afternoon high tide cycle. This a
result of very high seas just offshore and strong north to
northeast winds coupled with bands of heavy rain that may
be a factor.

High surf will continue into at least Saturday along the east 
side of Cape Cod and Nantucket with lingering beach erosion. 
Some beach erosion may also persist along south facing ocean 
exposures. 

Swells from Maria may re-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...Tropical Storm Warning for MAZ022>024. 
     High Surf Advisory until 6 AM EDT Saturday for MAZ007-019-020.
     Wind Advisory until 6 PM EDT this evening for MAZ018>021.
RI...Tropical Storm Warning for RIZ008. 
     High Surf Advisory until 6 AM EDT Saturday for RIZ006-007.
     Wind Advisory until 6 PM EDT this evening for RIZ005>007.
MARINE...Tropical Storm Warning for ANZ231>235-237-250-254>256. 
     Small Craft Advisory until 8 PM EDT this evening for ANZ230.
     Small Craft Advisory until 6 PM EDT this evening for ANZ236-
     251.

&&

$$
SYNOPSIS...WTB/JWD
NEAR TERM...Frank

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