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000
FXUS61 KBOX 290227
AFDBOX

Area Forecast Discussion
National Weather Service Taunton MA
1026 PM EDT SAT MAY 28 2016

.SYNOPSIS...

A backdoor cold front begins to drop S over E/NE MA. Ahead of this
front on Sunday, scattered showers and thunderstorms redevelop,
especially across western MA and CT. Expecting rain late Sunday
night through Memorial Day, heavy at times, with the chance of
thunderstorms. With tropical moisture streaming north from Tropical
Depression Number 2, there is a potential threat for localized flash
flooding. A renewed strong to severe weather threat is possible over
interior New England late Monday. Dry conditions with warm
afternoons follow Tuesday into Wednesday.  Unsettled weather may return
by the end of next week.

&&

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

1025 pm update...

Still very mild late this evening with temps mainly in the 70s to even
the lower 80s in Boston. Main story overnight will be a backdoor
cold front that will slip south into north central and northeast MA
by daybreak.  This will allow cooler marine air to work into this
region allowing low temps to drop to between 60 and 65 by daybreak.
Meanwhile, portions of western Ma and northern CT will see overnight
lows mainly in the upper 60s to near 70.

Despite some elevated instability, not much forcing for
precipitation overnight.  Can not rule out a brief spot shower/t-
storm but that vast majority of the night will remain dry.  Patchy
fog may develop in the typically prone locations and may end up a
bit more widespread across northeast MA behind the backdoor cold
front.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
Sunday...

Cooler conditions push into N/E MA associated with a backdoor cold
front as shower and thunderstorm activity emerges across the S/W
interior. Two airmasses to contend with as there is some trickiness
in nailing down specifically where the dividing line will set up
especially with respect to temperature forecasts.

With confidence, behind the backdoor cold front cooler conditions
will prevail with NE flow and low clouds. A definite chill to the
air as it will be roughly some 20 degrees cooler than the day prior
with highs around 70 degrees.

S/W, warmer conditions with highs close to 90, especially in the
lower CT River Valley. Likely scattered shower and thunderstorm
activity with increasing S winds ahead of a strong synoptic
disturbance over the Great Lakes Region. Despite continued mid to
upper level ridging and limited upper level support, albeit
weakening, slightly stronger shear coupled with robust instability
throughout the entire atmospheric layer up to the equilibrium level
yields the potential for strong thunderstorms over N/W interior
portions of MA and CT. Storms have the potential for producing heavy
rain, perhaps even gusty winds and small hail considering the CAPE
and shear profiles. But again, missing the upper level support, much
of the forcing confined to the low to mid levels, especially more so
wherever the increasing S flow converges with high terrain in areas
of high instability. This coinciding with SPC`s Day 2 outlook of a
general thunder risk.

One final note concerning the thunderstorm threat, consensus of
models have some drier air working N along with the increasing S
winds ahead of the tropical moist plume for Sunday night into
Monday. Timing uncertain, it could throw a wrench in the entire cog-
wheel process of convection, pushing the focus area of activity
further N/W outside of MA and CT. Will watch this closely, but aside
the consensus of overall guidance has a potential threat for N/W
portions of CT and MA.

Sunday Night into Monday...

With convection concluding into the evening hours, becoming dry,
focus of attention shifts towards a moderate to heavy rainfall event
developing late overnight and continuing through Monday as moisture
associated with Tropical Depression 2 streams N ahead of a series of
trailing cold fronts associated with a synoptic trough disturbance
sweeping W to E.

Focus is upon areas of deep layer lift, specifically where the right
entrance region of the upper level jet aligns with mid level vortex
energy out ahead of the deamplifying trough pattern, and with
convergent low to mid level forcing along and ahead of an initial
sweeping pre-frontal boundary. This with a deep-layer SW to NE
training environment of warm-moist tropical-origin airmass with
precipitable waters up to around 2-inches, near-record highest for
the end of May looking at atmospheric sounding climatologies. H85
dewpoints in excess of 10C, mixing ratios above 12 g/kg, and some
elevated instability.

In all, and per a consensus of the guidance, expect a sweeping band
of moderate to heavy rainfall, W to E, with embedded thunderstorm
activity. There is perhaps some model forecast struggle with amounts
and location of heavy rainfall / localized flooding, given the
uncertainty as to how fast the cold front will sweep S New England
and subsequent time in which the tropical-origin moist plume
environment will be over any one region. But aside, the overall take-
away is that there is a flash flood potential especially for urban
centers should tropical-origin rains stream SW to NE over any one
area for a prolonged period of time, transitioning through the
period from early Monday morning into evening W to E. Keep in mind
this is quite an infrequent event for this time of year.

Now as this activity moves out, there is still the mid to upper
level synoptic trough disturbance and accompanying surface cold
front ahead of which partial clearing is forecast in wake of a pre-
frontal boundary and tropical moisture. A rebound in instability
beneath stronger W/SW flow and subsequent shear, SPC Day 3 forecast
has a marginal threat mainly N/W of S New England for strong to
severe thunderstorms with threats of heavy rain, strong to
damaging winds, and small hail. Timing is an issue as to how
quickly tropical- origin activity will exit to the E and the
atmosphere over W New England can rebound and destabilize. During
the late afternoon and towards evening, it is quite possible that
thunderstorm activity could enter W New England. Something to
watch out

Monday Night...

Convective activity withers with the lack of diurnal heating. The
associated cold front weakening sweeps SE across S New England
behind which W/NW follows pushing into the region much cooler and
drier air, while shunting tropical moisture out to sea. Will see
lows drop back into the 50s.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
Highlights...

* Mainly dry with above normal temperatures Tue/Wed
* Unsettled weather may return toward next weekend

Details...

Tuesday and Wednesday...

Dry weather with above normal afternoon highs are anticipated
away from the immediate coast. Dewpoints mainly from 55 to 60, so
it will still feel humid.

Thursday into Saturday...

Forecast confidence remains rather low for this time frame.
Increasing humidity with south winds ahead of an approaching cold
front, especially Friday into Saturday. Timing this front remains
one of the biggest challenges. Showers, and perhaps a few
thunderstorms, possible. Way too early to try to narrow down the
timing, although afternoon and evening hours would be
climatologically favored. Kept just a chance for measurable
rainfall in the forecast, until the details become more clear.

&&

.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
Forecaster Confidence Levels.

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

Short Term /through Monday Night/...

Overnight...Moderate to high confidence.  Mainly VFR but may see
some patchy fog resulting in some MVFR conditions after midnight.
Also, backdoor cold front may allow a deck of 1000 to 1500 foot
stratus and perhaps some fog to slide into Northeast MA including
Boston near 12z.

Sunday...Moderate Confidence.

Winds back NE across E/NE MA with MVFR/IFR cig and vsby impacts.
Towards the SW of this wind shift, SCT SHRA/TSRA expected with
TEMPO MVFR/IFR impacts and possible 20-40 kt gusts. Focus around
midday into afternoon. S winds overall for those areas S/SW of the
NE wind shift.

Sunday Night into Monday...Moderate Confidence.

MVFR/IFR as RA/+RA with possible TSRA sweep W to E through the
day. Cig and vsby impacts with strong S winds gusting 20 to 25
kts. For those areas W that clear out earlier, there is the
potential for additional SHRA/TSRA activity late in the day. Low
confidence with respect to impacts/outcomes.

KBOS TAF...Moderate to high confidence in TAF.  Mainly VFR overnight
but probably will see low end MVFR CIGS arrive near 12z behind the
backdoor cold front.

KBDL TAF...Moderate to high confidence in TAF.

Outlook /Tuesday through Thursday/...

High confidence VFR. Low probability for MVFR in isolated showers
or thunderstorms Thursday.

&&

.MARINE...
Forecaster Confidence Levels.

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

Short Term /through Monday Night/...High confidence.

S/SW winds prevailing with gusts up around 20 kts and seas holding
below 5 feet through Sunday evening over the S waters. Some
visibility restrictions with mist or patchy fog not out of the
question with warm-moist air streaming over the cooler waters.
Whereas the E waters winds will shift out of the NE briefly
tonight and through Sunday before reverting back out of the S/SW.

Late Sunday night into Monday will see tropical moisture associated
with TD 2 yield rain, locally heavy at times, along with the
chance of thunderstorms across all waters. Likely visibility
restrictions in accordance with rain, along with mist or fog
forecast. Pronounced S/SW winds ahead of the front with gusts up
to 25 kts look to yield seas of 5 to 6 feet Monday into Monday
evening. Small Craft Advisories may be needed.

All this activity clears out late into Monday night as a cold
front sweeps the waters behind which winds back out of the W.

Outlook /Tuesday through Thursday/...

Tuesday...High confidence. Lingering 5 foot swell possible across
our southern waters , but should diminish by late Tuesday night.

Wednesday and Thursday...Moderate confidence. Relatively tranquil
boating weather. Increasing east winds Thursday could lead to some
rough seas across the outermost coastal waters Thursday afternoon
and evening.

&&

.CLIMATE...
Record highs for today, Saturday May 28...

Boston...          92 Tied (also set in 1931)
Providence...      91 set in 1931
Hartford...        93 Tied (also set in 1977)
Worcester...       89 New Record (previously 88 in 1929, 1911)
Milton/Blue Hill...91 New Record(previously 90 in 1929)

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...Air Quality Alert until 11 PM EDT this evening for CTZ002>004.
MA...Air Quality Alert until 11 PM EDT this evening for MAZ004>007-
     009>018-026.
RI...Air Quality Alert until 11 PM EDT this evening for RIZ001>005.
MARINE...None.

&&

$$
SYNOPSIS...Belk/Sipprell
NEAR TERM...Frank
SHORT TERM...Sipprell
LONG TERM...Belk
AVIATION...Frank/Belk/Sipprell
MARINE...Belk/Sipprell
CLIMATE...Staff





000
FXUS61 KBOX 282346
AFDBOX

Area Forecast Discussion
National Weather Service Taunton MA
746 PM EDT SAT MAY 28 2016

.SYNOPSIS...
Any isolated shower or thunderstorm diminishes overnight as a
backdoor cold front begins to drop S over E/NE MA. Ahead of this
front on Sunday, scattered showers and thunderstorms redevelop,
especially across western MA and CT. Expecting rain late Sunday
night through Memorial Day, heavy at times, with the chance of
thunderstorms. With tropical moisture streaming north from
Tropical Depression Number 2, there is a potential threat for
localized flash flooding. A renewed strong to severe weather
threat is possible over interior New England late Monday. Dry
conditions with warm afternoons follow Tuesday into Wednesday.
Unsettled weather may return by the end of next week.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
7 pm update...

With sunset approaching fast, losing the large instability
generated in the heat and humidity this afternoon. Showers
diminishing. Mainly brought the forecast for the next few hours
back in line with observed trends.

Otherwise, some record-highs either tied or broken, please see the
climate discussion below. Highs well into the 90s.

Tonight...

While overwhelmingly quiet there are two areas of concern: the first
being potential remnant convection, the second low clouds and
possible visibility issues per mist/fog N and E as a backdoor cold
front sulks S into E/NE MA. Otherwise a mild night with lows in the
60s.

With any remnant convection should it persist after sunset, activity
moves E/SE with the mean wind across E/SE portions of New England.
Diurnal heating has concluded beneath the mid to upper level ridge
resulting in the boundary layer to decouple as it cools. Yet despite
there is still some elevated instability to work with especially if
a parcel were to be lifted above the boundary layer inversion. If
any convection should continue, a heavy rain and/or lightning threat
is considered.

With regards to the backdoor cold front, winds back out of the NE
behind which cooler air follows. Across a previous moist environment
with dewpoints well into the 60s, likely to contend with low clouds
and some visibility restrictions with mist / fog as was the case
upstream last night over Maine. Quite possible visibilities could
fall at or lower than 1 to 2 miles. Something to watch closely
during the overnight hours as there would be subsequent travel
impacts.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
Sunday...

Cooler conditions push into N/E MA associated with a backdoor cold
front as shower and thunderstorm activity emerges across the S/W
interior. Two airmasses to contend with as there is some trickiness
in nailing down specifically where the dividing line will set up
especially with respect to temperature forecasts.

With confidence, behind the backdoor cold front cooler conditions
will prevail with NE flow and low clouds. A definite chill to the
air as it will be roughly some 20 degrees cooler than the day prior
with highs around 70 degrees.

S/W, warmer conditions with highs close to 90, especially in the
lower CT River Valley. Likely scattered shower and thunderstorm
activity with increasing S winds ahead of a strong synoptic
disturbance over the Great Lakes Region. Despite continued mid to
upper level ridging and limited upper level support, albeit
weakening, slightly stronger shear coupled with robust instability
throughout the entire atmospheric layer up to the equilibrium level
yields the potential for strong thunderstorms over N/W interior
portions of MA and CT. Storms have the potential for producing heavy
rain, perhaps even gusty winds and small hail considering the CAPE
and shear profiles. But again, missing the upper level support, much
of the forcing confined to the low to mid levels, especially more so
wherever the increasing S flow converges with high terrain in areas
of high instability. This coinciding with SPC`s Day 2 outlook of a
general thunder risk.

One final note concerning the thunderstorm threat, consensus of
models have some drier air working N along with the increasing S
winds ahead of the tropical moist plume for Sunday night into
Monday. Timing uncertain, it could throw a wrench in the entire cog-
wheel process of convection, pushing the focus area of activity
further N/W outside of MA and CT. Will watch this closely, but aside
the consensus of overall guidance has a potential threat for N/W
portions of CT and MA.

Sunday Night into Monday...

With convection concluding into the evening hours, becoming dry,
focus of attention shifts towards a moderate to heavy rainfall event
developing late overnight and continuing through Monday as moisture
associated with Tropical Depression 2 streams N ahead of a series of
trailing cold fronts associated with a synoptic trough disturbance
sweeping W to E.

Focus is upon areas of deep layer lift, specifically where the right
entrance region of the upper level jet aligns with mid level vortex
energy out ahead of the deamplifying trough pattern, and with
convergent low to mid level forcing along and ahead of an initial
sweeping pre-frontal boundary. This with a deep-layer SW to NE
training environment of warm-moist tropical-origin airmass with
precipitable waters up to around 2-inches, near-record highest for
the end of May looking at atmospheric sounding climatologies. H85
dewpoints in excess of 10C, mixing ratios above 12 g/kg, and some
elevated instability.

In all, and per a consensus of the guidance, expect a sweeping band
of moderate to heavy rainfall, W to E, with embedded thunderstorm
activity. There is perhaps some model forecast struggle with amounts
and location of heavy rainfall / localized flooding, given the
uncertainty as to how fast the cold front will sweep S New England
and subsequent time in which the tropical-origin moist plume
environment will be over any one region. But aside, the overall take-
away is that there is a flash flood potential especially for urban
centers should tropical-origin rains stream SW to NE over any one
area for a prolonged period of time, transitioning through the
period from early Monday morning into evening W to E. Keep in mind
this is quite an infrequent event for this time of year.

Now as this activity moves out, there is still the mid to upper
level synoptic trough disturbance and accompanying surface cold
front ahead of which partial clearing is forecast in wake of a pre-
frontal boundary and tropical moisture. A rebound in instability
beneath stronger W/SW flow and subsequent shear, SPC Day 3 forecast
has a marginal threat mainly N/W of S New England for strong to
severe thunderstorms with threats of heavy rain, strong to
damaging winds, and small hail. Timing is an issue as to how
quickly tropical- origin activity will exit to the E and the
atmosphere over W New England can rebound and destabilize. During
the late afternoon and towards evening, it is quite possible that
thunderstorm activity could enter W New England. Something to
watch out

Monday Night...

Convective activity withers with the lack of diurnal heating. The
associated cold front weakening sweeps SE across S New England
behind which W/NW follows pushing into the region much cooler and
drier air, while shunting tropical moisture out to sea. Will see
lows drop back into the 50s.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
Highlights...

* Mainly dry with above normal temperatures Tue/Wed
* Unsettled weather may return toward next weekend

Details...

Tuesday and Wednesday...

Dry weather with above normal afternoon highs are anticipated
away from the immediate coast. Dewpoints mainly from 55 to 60, so
it will still feel humid.

Thursday into Saturday...

Forecast confidence remains rather low for this time frame.
Increasing humidity with south winds ahead of an approaching cold
front, especially Friday into Saturday. Timing this front remains
one of the biggest challenges. Showers, and perhaps a few
thunderstorms, possible. Way too early to try to narrow down the
timing, although afternoon and evening hours would be
climatologically favored. Kept just a chance for measurable
rainfall in the forecast, until the details become more clear.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
Forecaster Confidence Levels.

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

Short Term /through Monday Night/...

Tonight...Moderate Confidence.

VFR. Isolated to scattered SHRA/TSRA erode SE across RI and SE MA
early with potential MVFR implications. Otherwise BR or patchy FG
possible East coast MA and NW MA. Light winds.

Sunday...Moderate Confidence.

Winds back NE across E/NE MA with MVFR/IFR cig and vsby impacts.
Towards the SW of this wind shift, SCT SHRA/TSRA expected with
TEMPO MVFR/IFR impacts and possible 20-40 kt gusts. Focus around
midday into afternoon. S winds overall for those areas S/SW of the
NE wind shift.

Sunday Night into Monday...Moderate Confidence.

MVFR/IFR as RA/+RA with possible TSRA sweep W to E through the
day. Cig and vsby impacts with strong S winds gusting 20 to 25
kts. For those areas W that clear out earlier, there is the
potential for additional SHRA/TSRA activity late in the day. Low
confidence with respect to impacts/outcomes.

KBOS TAF...VFR. Sea-breeze onshore, expected to erode as winds
turn back out of the W/SW during the evening. Through brief as
into Sunday winds backing E/NE during the day as cigs lower low-
end VFR possibly MVFR. Conditions prevailing into Monday, lowering
as RA/+RA move into the terminal during the later-half of the day.

KBDL TAF...VFR. Vicinity SHRA/TSRA this afternoon. Quiet tonight.
Vicinity TSRA possible again Sunday, but greater focus N/W of the
terminal. With any TSRA, TEMPO MVFR/IFR. S winds prevailing,
increasing ahead of RA/+RA expected early Monday morning through
roughly the middle portion of the day.

Outlook /Tuesday through Thursday/...

High confidence VFR. Low probability for MVFR in isolated showers
or thunderstorms Thursday.

&&

.MARINE...
Forecaster Confidence Levels.

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

Short Term /through Monday Night/...High confidence.

S/SW winds prevailing with gusts up around 20 kts and seas holding
below 5 feet through Sunday evening over the S waters. Some
visibility restrictions with mist or patchy fog not out of the
question with warm-moist air streaming over the cooler waters.
Whereas the E waters winds will shift out of the NE briefly
tonight and through Sunday before reverting back out of the S/SW.

Late Sunday night into Monday will see tropical moisture associated
with TD 2 yield rain, locally heavy at times, along with the
chance of thunderstorms across all waters. Likely visibility
restrictions in accordance with rain, along with mist or fog
forecast. Pronounced S/SW winds ahead of the front with gusts up
to 25 kts look to yield seas of 5 to 6 feet Monday into Monday
evening. Small Craft Advisories may be needed.

All this activity clears out late into Monday night as a cold
front sweeps the waters behind which winds back out of the W.

Outlook /Tuesday through Thursday/...

Tuesday...High confidence. Lingering 5 foot swell possible across
our southern waters , but should diminish by late Tuesday night.

Wednesday and Thursday...Moderate confidence. Relatively tranquil
boating weather. Increasing east winds Thursday could lead to some
rough seas across the outermost coastal waters Thursday afternoon
and evening.

&&

.CLIMATE...
Record highs for today, Saturday May 28...

Boston...          92 Tied (also set in 1931)
Providence...      91 set in 1931
Hartford...        93 Tied (also set in 1977)
Worcester...       89 New Record (previously 88 in 1929, 1911)
Milton/Blue Hill...91 New Record(previously 90 in 1929)

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...Air Quality Alert until 11 PM EDT this evening for CTZ002>004.
MA...Air Quality Alert until 11 PM EDT this evening for MAZ004>007-
     009>018-026.
RI...Air Quality Alert until 11 PM EDT this evening for RIZ001>005.
MARINE...None.

&&

$$
SYNOPSIS...Belk/Sipprell
NEAR TERM...Belk/Sipprell
SHORT TERM...Sipprell
LONG TERM...Belk
AVIATION...Belk/Sipprell
MARINE...Belk/Sipprell
CLIMATE...Sipprell





000
FXUS61 KBOX 281145
AFDBOX

Area Forecast Discussion
National Weather Service Taunton MA
745 AM EDT SAT MAY 28 2016

.SYNOPSIS...

Hot weather is on tap for all but portions of the immediate coast
today.  While the majority of the region will remain dry, isolated
showers/thunderstorms will occur early this morning and again this
afternoon.  A backdoor cold front will bring cooler temperatures to
eastern MA Sunday but it will remain very warm across the interior,
where scattered showers and thunderstorms likely develop during the
afternoon. Tropical moisture will bring showers with locally heavy
rainfall very late Sunday night into Memorial Day.  Dry conditions
with warm afternoons follows Tuesday into Wednesday, but unsettled
weather may return by the end of next week.

&&

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

745 AM UPDATE...

Cluster of showers/thunderstorms that crossed the Islands earlier
this morning has moved off the coast.  Other than perhaps a left over
spot shower or two this morning, dry weather will prevail for the
bulk of the morning.

Previous forecast on track: Expect temperatures to soar with very
warm airmass across the region. Noting H925 temps up to +20C to
+22C, and H85 temps at +15C to +16C early this morning. Good mid
layer cap in place, up to H85 as seen on 00Z NAM and GFS model
soundings, so this has to break in order get some convection
going. BUFKIT soundings suggesting the convective temps need to
reach the lower 90s to break the cap, which looks like it will
happen especially across inland areas. Some question as the the
timing of the precip, but have kept good continuity with previous
forecasts. Kept slight chance to low chance POPs for this
afternoon and evening mainly central and western areas, but can
not rule out isolated convection somewhat closer to the coast.
Will be tough along the S coast with onshore winds though.

Expect daytime highs to reach the lower-mid 90s, with some of our
long term climate locations possibly approaching or exceeding
record levels. Check the climate section below for specifics.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
Tonight...With continued S-SW wind flow in place, low to mid
level moisture will continue to increase as dewpts will rise to
the lower- mid 60s. Leftover showers/thunderstorms may reach
toward the coast before dissipating this evening. May also see
some patchy fog develop across the normally prone inland valley
after midnight. Expect overnight lows mainly in the 60s, mildest
in the urban centers.

May see a backdoor cold front start to work southwestward down
from the Maine coast overnight. Model guidance suggesting winds
shifting to N-NE after 06Z around Cape Ann as well as temperatures
dropping to around 60, and may reach close to Boston by daybreak.

Sunday...Expect the backdoor cold front to push further S-SW
during the day. The big question will be where this front will
stall, as it appears it will stall somewhere across the region.
This will be a catalyst for convection though, especially near and
south of the front. Have at least slight chance POPs across most
areas, but looks like best shot for convection will be from W of
Fitchburg to W of Willimantic where better instability is also in
place along with the mildest temperatures. SPC has a mention of
general thunder for central and western areas.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...

Highlights...

* Heavy rain showers Memorial Day with localized flooding possible
* Mainly dry w/near or above normal temps Tue/Wed
* Unsettled weather may return late Thu/Fri or next weekend

Details...

Sunday night and Memorial Day...

Any left over scattered convection across interior southern New
England will quickly diminish early Sunday evening with the loss
of daytime heating. The rest of the evening will mainly be dry
other than perhaps a spot shower or two, but some fog may develop.

Things then become quite interesting very late Sunday night into
Memorial day. Tropical depression 2 currently several hundred
miles southeast of Charleston South Carolina is expected to become
Tropical Storm Bonnie today. This storm is then expected to track
northwest and approach the Carolina coast Sunday, then move very
slowly northeast through the middle of next week remaining well
south of our region. This tropical storm will not have a direct
impact in southern New England, and none of Bonnie`s winds/storm
surge will affect our region.

While a direct impact will not occur, an approaching cold front
will pull a plume of its tropical moisture northward into southern
New England. PWATS approach or possibly exceed 2 inches, which
will be near record high levels based on historical upper air data
for this time of year. The guidance also signals the development
of a SSW 30 to 40 knot low level jet by 12z Monday which is 2+
standard deviations above normal. This all means we should see
bands of heavy rain showers develop very late Sunday night/early
Monday morning. Given the anomalously high PWATS combined with the
low level jet, there will be a risk for localized flooding.

While the models do a very good job these days in indicating
potential for heavy rainfall/localized flooding, they often
struggle with the location. At this time, appears that a lot of
the guidance is indicating an initial band of heavy rain showers
across eastern NY state towards 12z Monday, close to the
shortwave/better dynamics. Western MA and Northern CT may be on
the eastern edge of this band, so this will have to be watched. It
then appears that a second band may develop later Monday
morning/afternoon across southeast MA/RI on the nose of a 40+ knot
low level jet. Some of the guidance has this lingering into Monday
evening, while other data dries us out by then.

So in a nutshell, expecting numerous showers with locally heavy
rainfall. Given the above parameters, it is certainly possible
that a narrow swath may see 2+ inches of rain in less than an
hour. So while widespread flooding is not expected...there
certainly is potential for localized flooding especially if a
heavy rain band sets up in one of our more vulnerable urban
centers. Greatest risk for that appears to be in our far western
zones and perhaps southeast New England on the nose of the low
level jet, but again that certainly is subject to shift.

Tuesday and Wednesday...

Dry weather with warm afternoon highs into the 80s are
anticipated away from the immediate coast Tue/Wed as a ridge of
high pressure builds over the region. Dewpoints will drop back
into the 50s though so will get rid of the humidity.

Thursday into Saturday...

Forecast confidence becomes quite low over this time. Upper level
ridge will eventually break down by the end of next week. Whether
that happens later Thu or holds off until next weekend is
uncertain, but once that occurs unsettled weather will return.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
Forecaster Confidence Levels.

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


Today...Moderate confidence. Mainly VFR. Isolated/brief MVFR-IFR
conditions in a few showers/t-storms but most of the region will
remain dry.

Tonight and Sunday...Moderate Confidence. Mainly VFR. Local MVFR-
IFR conditions in patchy fog late tonight into early Sunday
morning. Low probability of brief MVFR conditions in SCT afternoon
SHRA/TSRA across the interior.

KBOS TAF...High confidence in VFR but uncertain if we see a few
hours of an ESE sea breeze late this morning or afternoon.  Low risk
of a brief spot shower/t-storm.

KBDL TAF...High confidence in TAF. Low risk of a spot shower/t-storm
this afternoon.

Outlook /Sunday Night through Wednesday/...

Sunday night and Memorial Day...Moderate to high confidence.  MVFR-
IFR Cigs/Vsbys likely develop late Sunday night and continue into
Memorial Day.  This the result of low clouds...fog patches and heavy
rain showers.  Isolated thunderstorms are also possible.

Monday night through Wednesday...Moderate to high confidence.
Lingering MVFR-IFR conditions possible Monday evening, but
improvement to VFR Tue continuing Wed.

&&

.MARINE...
Forecaster Confidence Levels.

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

Short Term /through Sunday/...High confidence.

Through 12Z...Expect winds and seas to remain below small craft.
Will see S-SW winds gusting up to 20 kt on the southern outer
waters. May see some patchy fog with locally lower visibilities.
Locally heavy rainfall in sct showers/thunderstorms through 12Z
on the waters near and S of Nantucket and Martha`s Vineyard.

Today...S-SW winds gusting up to 20 kt through midday then will
diminish. Leftover isolated showers/thunderstorms with locally
heavy rainfall and reduced visibilities, as well as patchy fog
through late morning.

Tonight and Sunday...SW winds may gust up to 20 kt on the
southern waters this evening, otherwise winds and seas below
small craft criteria through Sunday. May see patchy fog with
locally reduced visibilities tonight into Sunday morning.

Outlook /Sunday Night through Wednesday/...

Sunday night through Monday night...Moderate to high confidence.
Quiet Sunday night on the waters other than some fog. We may see
some southwest wind gusts to 25 knots develop Monday morning and
continue into the afternoon with the aid of a low level jet along
with heavy showers/isolated thunderstorms. Marginal 5 foot seas
may also develop across our southern waters late Mon into Mon
night.

Tuesday and Wednesday...Moderate to high confidence. Lingering 5
foot swell possible across our southern waters Tue, but should
diminish by late Tue night. Otherwise, a ridge of high pressure
will keep winds/seas below small craft advisory thresholds with
good visibility into Wed.

&&

.CLIMATE...
Some of today`s record highs may be challenged as temperatures
reach the lower-mid 90s.

Record highs for today, Saturday May 28...

Boston...92 set in 1931
Providence...91 set in 1931
Hartford...93 set in 1977
Worcester...88 set in 1911 and 1929
Milton/Blue Hill...90 set in 1929

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...Air Quality Alert from 11 AM this morning to 11 PM EDT this
     evening for CTZ002>004.
MA...Air Quality Alert from 11 AM this morning to 11 PM EDT this
     evening for MAZ004>007-009>018-026.
RI...None.
MARINE...None.

&&

$$
SYNOPSIS...EVT/Frank
NEAR TERM...Frank/EVT
SHORT TERM...EVT
LONG TERM...Frank
AVIATION...EVT/Frank
MARINE...EVT/Frank
CLIMATE...Staff





000
FXUS61 KBOX 280920
AFDBOX

Area Forecast Discussion
National Weather Service Taunton MA
520 AM EDT SAT MAY 28 2016

.SYNOPSIS...
Hot weather is on tap for all but portions of the immediate coast
today.  While the majority of the region will remain dry, isolated
showers/thunderstorms will occur early this morning and again this
afternoon.  A backdoor cold front will bring cooler temperatures to
eastern MA Sunday but it will remain very warm across the interior,
where scattered showers and thunderstorms likely develop during the
afternoon. Tropical moisture will bring showers with locally heavy
rainfall very late Sunday night into Memorial Day.  Dry conditions
with warm afternoons follows Tuesday into Wednesday, but unsettled
weather may return by the end of next week.

&&

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

Strong low level jet /with h925 W-SW winds up to 35-40 kt/ along
with low level moisture and good elevated instability /TQ values
up to around 20/ caused a line of showers and scattered
thunderstorms that developed off the RI coast early this morning.
This line continues to push E near and S of Martha`s Vineyard at
08Z. Expect the line to cross Nantucket and Nantucket Sound as
well as the waters S of the islands, then should weaken with
sunrise as it continues eastward.

Also have noted a few showers that have moved into the mid Hudson
valley into the central Berkshires at 08Z, which may hold together
through sunrise across the CT valley of Mass. Noticing a band of
mid and high clouds crossing the region on IR satellite imagery,
but should push offshore by mid morning allowing for partly to
mostly sunny skies.

Once the sun does come out, expect temperatures to soar with very
warm airmass across the region. Noting H925 temps up to +20C to
+22C, and H85 temps at +15C to +16C early this morning. Good mid
layer cap in place, up to H85 as seen on 00Z NAM and GFS model
soundings, so this has to break in order get some convection
going. BUFKIT soundings suggesting the convective temps need to
reach the lower 90s to break the cap, which looks like it will
happen especially across inland areas. Some question as the the
timing of the precip, but have kept good continuity with previous
forecasts. Kept slight chance to low chance POPs for this
afternoon and evening mainly central and western areas, but can
not rule out isolated convection somewhat closer to the coast.
Will be tough along the S coast with onshore winds though.

Expect daytime highs to reach the lower-mid 90s, with some of our
long term climate locations possibly approaching or exceeding
record levels. Check the climate section below for specifics.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...

Tonight...With continued S-SW wind flow in place, low to mid
level moisture will continue to increase as dewpts will rise to
the lower- mid 60s. Leftover showers/thunderstorms may reach
toward the coast before dissipating this evening. May also see
some patchy fog develop across the normally prone inland valley
after midnight. Expect overnight lows mainly in the 60s, mildest
in the urban centers.

May see a backdoor cold front start to work southwestward down
from the Maine coast overnight. Model guidance suggesting winds
shifting to N-NE after 06Z around Cape Ann as well as temperatures
dropping to around 60, and may reach close to Boston by daybreak.

Sunday...Expect the backdoor cold front to push further S-SW
during the day. The big question will be where this front will
stall, as it appears it will stall somewhere across the region.
This will be a catalyst for convection though, especially near and
south of the front. Have at least slight chance POPs across most
areas, but looks like best shot for convection will be from W of
Fitchburg to W of Willimantic where better instability is also in
place along with the mildest temperatures. SPC has a mention of
general thunder for central and western areas.

&&

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

* Heavy rain showers Memorial Day with localized flooding possible
* Mainly dry w/near or above normal temps Tue/Wed
* Unsettled weather may return late Thu/Fri or next weekend

Details...

Sunday night and Memorial Day...

Any left over scattered convection across interior southern New
England will quickly diminish early Sunday evening with the loss
of daytime heating. The rest of the evening will mainly be dry
other than perhaps a spot shower or two, but some fog may develop.

Things then become quite interesting very late Sunday night into
Memorial day. Tropical depression 2 currently several hundred
miles southeast of Charleston South Carolina is expected to become
Tropical Storm Bonnie today. This storm is then expected to track
northwest and approach the Carolina coast Sunday, then move very
slowly northeast through the middle of next week remaining well
south of our region. This tropical storm will not have a direct
impact in southern New England, and none of Bonnie`s winds/storm
surge will affect our region.

While a direct impact will not occur, an approaching cold front
will pull a plume of its tropical moisture northward into southern
New England. PWATS approach or possibly exceed 2 inches, which
will be near record high levels based on historical upper air data
for this time of year. The guidance also signals the development
of a SSW 30 to 40 knot low level jet by 12z Monday which is 2+
standard deviations above normal. This all means we should see
bands of heavy rain showers develop very late Sunday night/early
Monday morning. Given the anomalously high PWATS combined with the
low level jet, there will be a risk for localized flooding.

While the models do a very good job these days in indicating
potential for heavy rainfall/localized flooding, they often
struggle with the location. At this time, appears that a lot of
the guidance is indicating an initial band of heavy rain showers
across eastern NY state towards 12z Monday, close to the
shortwave/better dynamics. Western MA and Northern CT may be on
the eastern edge of this band, so this will have to be watched. It
then appears that a second band may develop later Monday
morning/afternoon across southeast MA/RI on the nose of a 40+ knot
low level jet. Some of the guidance has this lingering into Monday
evening, while other data dries us out by then.

So in a nutshell, expecting numerous showers with locally heavy
rainfall. Given the above parameters, it is certainly possible
that a narrow swath may see 2+ inches of rain in less than an
hour. So while widespread flooding is not expected...there
certainly is potential for localized flooding especially if a
heavy rain band sets up in one of our more vulnerable urban
centers. Greatest risk for that appears to be in our far western
zones and perhaps southeast New England on the nose of the low
level jet, but again that certainly is subject to shift.

Tuesday and Wednesday...

Dry weather with warm afternoon highs into the 80s are
anticipated away from the immediate coast Tue/Wed as a ridge of
high pressure builds over the region. Dewpoints will drop back
into the 50s though so will get rid of the humidity.

Thursday into Saturday...

Forecast confidence becomes quite low over this time. Upper level
ridge will eventually break down by the end of next week. Whether
that happens later Thu or holds off until next weekend is
uncertain, but once that occurs unsettled weather will return.

&&

.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
Forecaster Confidence Levels.

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

Through 12Z...Moderate confidence. Mainly VFR conditions. May see
local visibilities to MVFR-IFR in any patchy fog that may develop
across the locally prone inland valleys and along the immediate
coast. Sct showers/tstms with local IFR conditions passing near
Martha`s Vineyard and Nantucket, which should start to weaken
around 12Z.

Today...Moderate confidence. Mainly VFR. Low risk for MVFR-IFR
conditions in widely scattered showers and thunderstorms this
afternoon away from the coast.

Tonight and Sunday...Moderate Confidence. Mainly VFR. Local MVFR-
IFR conditions in patchy fog late tonight into early Sunday
morning. Low probability of brief MVFR conditions in SCT afternoon
SHRA/TSRA across the interior.

KBOS TAF...High confidence in TAF.

KBDL TAF...High confidence in TAF.

Outlook /Sunday Night through Wednesday/...

Sunday night and Memorial Day...Moderate to high confidence.  MVFR-
IFR Cigs/Vsbys likely develop late Sunday night and continue into
Memorial Day.  This the result of low clouds...fog patches and heavy
rain showers.  Isolated thunderstorms are also possible.

Monday night through Wednesday...Moderate to high confidence.
Lingering MVFR-IFR conditions possible Monday evening, but
improvement to VFR Tue continuing Wed.

&&

.MARINE...
Forecaster Confidence Levels.

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

Short Term /through Sunday/...High confidence.

Through 12Z...Expect winds and seas to remain below small craft.
Will see S-SW winds gusting up to 20 kt on the southern outer
waters. May see some patchy fog with locally lower visibilities.
Locally heavy rainfall in sct showers/thunderstorms through 12Z
on the waters near and S of Nantucket and Martha`s Vineyard.

Today...S-SW winds gusting up to 20 kt through midday then will
diminish. Leftover isolated showers/thunderstorms with locally
heavy rainfall and reduced visibilities, as well as patchy fog
through late morning.

Tonight and Sunday...SW winds may gust up to 20 kt on the
southern waters this evening, otherwise winds and seas below
small craft criteria through Sunday. May see patchy fog with
locally reduced visibilities tonight into Sunday morning.

Outlook /Sunday Night through Wednesday/...

Sunday night through Monday night...Moderate to high confidence.
Quiet Sunday night on the waters other than some fog. We may see
some southwest wind gusts to 25 knots develop Monday morning and
continue into the afternoon with the aid of a low level jet along
with heavy showers/isolated thunderstorms. Marginal 5 foot seas
may also develop across our southern waters late Mon into Mon
night.

Tuesday and Wednesday...Moderate to high confidence. Lingering 5
foot swell possible across our southern waters Tue, but should
diminish by late Tue night. Otherwise, a ridge of high pressure
will keep winds/seas below small craft advisory thresholds with
good visibility into Wed.

&&

.CLIMATE...

Some of today`s record highs may be challenged as temperatures
reach the lower-mid 90s.

Record highs for today, Saturday May 28...

Boston...92 set in 1931
Providence...91 set in 1931
Hartford...93 set in 1977
Worcester...88 set in 1911 and 1929
Milton/Blue Hill...90 set in 1929

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...Air Quality Alert from 11 AM this morning to 11 PM EDT this
     evening for CTZ003-004.
MA...Air Quality Alert from 11 AM this morning to 11 PM EDT this
     evening for MAZ004>007-009>018-026.
RI...None.
MARINE...None.

&&

$$
SYNOPSIS...Frank/EVT
NEAR TERM...EVT
SHORT TERM...EVT
LONG TERM...Frank
AVIATION...Frank/EVT
MARINE...Frank/EVT
CLIMATE...EVT





000
FXUS61 KBOX 280844
AFDBOX

Area Forecast Discussion
National Weather Service Taunton MA
443 AM EDT SAT MAY 28 2016

.SYNOPSIS...

Hot weather is on tap for all but portions of the immediate coast
today.  While the majority of the region will remain dry, isolated
showers/thunderstorms will occur early this morning and again this
afternoon.  A backdoor cold front will bring cooler temperatures to
eastern MA Sunday but it will remain very warm across the interior,
where scattered showers and thunderstorms likely develop during the
afternoon. Tropical moisture will bring showers with locally heavy
rainfall very late Sunday night into Memorial Day.  Dry conditions
with warm afternoons follows Tuesday into Wednesday, but unsettled
weather may return by the end of next week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1150 PM Update...

A few spotty showers, one with a quick rumble of thunder, have
crossed into far NW Mass at 03Z. Expect these to weaken as they
shift E over the next few hours.

00Z high resolution models as well as the GFS/NAM are all
indicating the development of scattered showers/thunderstorms
around or after 06Z as a strong W-SW low level jet moves near and
just S of the S coast. Starting to note a few showers developing
on the twin forks of Long Island on latest KBOX 88D radar.

Will also see fog redevelop across the southern waters, possibly
reaching the S coast, Cape Cod and the islands overnight. GOES-E
experimental aviation MVFR/IFR/LIFR percentages, and start to see
at least MVFR conditions could move into the Cape and islands
overnight as the low clouds and fog develop.

Remainder of the forecast looks in pretty good shape, but have
updated to bring conditions current.

Previous Discussion...

With light winds and increasing moisture in the air, we are
likely to have another round of fog. This will favor coastal areas
as well as typical inland fog spots. The fog may be locally dense,
and may require a dense fog advisory once confidence is higher in
its location.

Otherwise, mins only fall into the low-mid 60s again tonight
thanks to high crossover temps and lingering clouds.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
Saturday...
Mid lvl ridging continues with rising heights across the region
and plenty of sunshine. No trouble mixing to at least H85 where
temps will approach +16C by afternoon peak heating. Weak return
flow will limit sea breezes to mainly the south coast. Therefore,
still expecting probably the hottest day we have seen thus far
with highs topping out in the low-mid 90s across much of the
region away from S coastal areas. Dwpts will remain elevated as
well, mainly in the low-mid 60s even during peak mixing.

The other issue will be convective potential. Plenty of SFC/mixed
lvl CAPE would be available, except the rising heights and modest
subsidence it/s associated with is likely to yield a slight
capping inversion and limit updraft development. Lapse rates are
modest, mainly approaching 6.0C/KM in the mid lvls, but this is
most likely a reflection of the mid lvl dry air. Even the latest
12Z ECMWF now is almost NIL for QPF during the afternoon and
evening hours. Definitely not going NIL given the rising PWATs and
potential energy available if the cap is broken, but will limit it
mainly to slight and low end chance across the terrain and along
developing sea breezes where at least some lift will be available.
T-storms will be mainly airmass-type as shear is also quite
limited.

Saturday night...
Continued increase in low-mid lvl moisture will actually help to
erode the cap and allow for some maintenance of any shra/t-storms
that develop, so will be slow to drop overnight POPs. Otherwise,
the increase in moisture beneath the inversion increases the risk
for overnight fog development which once again has the risk of
being locally dense at times and may require headlines. Otherwise,
another mild night with mins only falling back into the 60s.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...

Highlights...

* Heavy rain showers Memorial Day with localized flooding possible
* Mainly dry w/near or above normal temps Tue/Wed
* Unsettled weather may return late Thu/Fri or next weekend

Details...

Sunday night and Memorial Day...

Any left over scattered convection across interior southern New
England will quickly diminish early Sunday evening with the loss of
daytime heating.  The rest of the evening will mainly be dry other
than perhaps a spot shower or two, but some fog may develop.

Things then become quite interesting very late Sunday night into
Memorial day.  Tropical depression 2 currently several hundred miles
southeast of Charleston South Carolina is expected to become
Tropical Storm Bonnie today.  This storm is then expected to track
northwest and approach the Carolina coast Sunday, then move very
slowly northeast through the middle of next week remaining well
south of our region.  This tropical storm will not have a direct
impact in southern New England, and none of Bonnie`s winds/storm
surge will affect our region.

While a direct impact will not occur, an approaching cold front will
pull a plume of its tropical moisture northward into southern New
England. PWATS approach or possibly exceed 2 inches, which will be
near record high levels based on historical upper air data for this
time of year.  The guidance also signals the development of a SSW 30
to 40 knot low level jet by 12z Monday which is 2+ standard
deviations above normal.  This all means we should see bands of
heavy rain showers develop very late Sunday night/early Monday
morning.  Given the anomalously high PWATS combined with the low
level jet, there will be a risk for localized flooding.

While the models do a very good job these days in indicating
potential for heavy rainfall/localized flooding, they often struggle
with the location.  At this time, appears that a lot of the guidance
is indicating an initial band of heavy rain showers across eastern
NY state towards 12z Monday, close to the shortwave/better dynamics.
Western MA and Northern CT may be on the eastern edge of this band,
so this will have to be watched. It then appears that a second band
may develop later Monday morning/afternoon across southeast MA/RI on
the nose of a 40+ knot low level jet.  Some of the guidance has this
lingering into Monday evening, while other data dries us out by then.

So in a nutshell, expecting numerous showers with locally heavy
rainfall.  Given the above parameters, it is certainly possible that
a narrow swath may see 2+ inches of rain in less than an hour. So
while widespread flooding is not expected...there certainly is
potential for localized flooding especially if a heavy rain band
sets up in one of our more vulnerable urban centers.  Greatest risk
for that appears to be in our far western zones and perhaps
southeast New England on the nose of the low level jet, but again
that certainly is subject to shift.

Tuesday and Wednesday...

Dry weather with warm afternoon highs into the 80s are anticipated
away from the immediate coast Tue/Wed as a ridge of high pressure
builds over the region.  Dewpoints will drop back into the 50s
though so will get rid of the humidity.

Thursday into Saturday...

Forecast confidence becomes quite low over this time.  Upper level
ridge will eventually break down by the end of next week.  Whether
that happens later Thu or holds off until next weekend is uncertain,
but once that occurs unsettled weather will return.

&&

.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
Forecaster Confidence Levels.

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

Tonight...Moderate confidence. Mainly VFR through about 06Z
inland, then patchy fog possible especially at typically prone
airports with localized MVFR/IFR conditions. Another risk for
LIFR along Cape Cod and Island terminals overnight into Saturday
morning.

Saturday and Saturday night...Moderate confidence. Mainly VFR.
Local MVFR-IFR conditions in patchy fog through mid morning. Low
probability of brief MVFR conditions in SCT afternoon SHRA/TSRA
across the interior. Another risk for overnight fog tomorrow
night.

KBOS TAF...High confidence in TAF.

KBDL TAF...High confidence in TAF.

Outlook /Sunday night through Wednesday/...

Sunday night and Memorial Day...Moderate to high confidence.  MVFR-
IFR Cigs/Vsbys likely develop late Sunday night and continue into
Memorial Day.  This the result of low clouds...fog patches and heavy
rain showers.  Isolated thunderstorms are also possible.

Monday night through Wednesday...Moderate to high confidence.
Lingering MVFR-IFR conditions possible Monday evening, but
improvement to VFR Tue continuing Wed.

&&

.MARINE...
Forecaster Confidence Levels.

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

Short Term /through Sunday/...High confidence.

Overnight...
Winds and seas remain below small craft criteria. There will be
some fog to contend with. The fog could be quite dense at times
and may take some time to burn off even after sunrise.

Saturday and Saturday night...
Seas on the southern outer waters may briefly reach 5 feet at
times but should diminish again at night. South to southwest
winds will remain less than 20 knots. More fog may develop
Saturday night.

Outlook /Sunday night through Wednesday/...

Sunday night through Monday night...Moderate to high confidence.
Quiet Sunday night on the waters other than some fog.  We may see
some southwest wind gusts to 25 knots develop Monday morning and
continue into the afternoon with the aid of a low level jet along
with heavy showers/isolated thunderstorms. Marginal 5 foot seas may
also develop across our southern waters late Mon into Mon night.

Tuesday and Wednesday...Moderate to high confidence.  Lingering 5
foot swell possible across our southern waters Tue, but should
diminish by late Tue night.  Otherwise, a ridge of high pressure
will keep winds/seas below small craft advisory thresholds with good
visibility into Wed.

&&

.CLIMATE...
Some record highs may be challenged as temperatures will be the
warmest on Saturday.

Record highs for Saturday May 28...

Boston...92 set in 1931
Providence...91 set in 1931
Hartford...93 set in 1977
Worcester...88 set in 1911 and 1929
Milton/Blue Hill...90 set in 1929

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...Air Quality Alert from 11 AM this morning to 11 PM EDT this
     evening for CTZ003-004.
MA...Air Quality Alert from 11 AM this morning to 11 PM EDT this
     evening for MAZ004>007-009>018-026.
RI...None.
MARINE...None.

&&

$$
SYNOPSIS...Frank/EVT
NEAR TERM...EVT-Coming Soon
SHORT TERM...EVT-Coming Soon
LONG TERM...Frank
AVIATION...EVT/Frank
MARINE...EVT/Frank
CLIMATE...Staff





000
FXUS61 KBOX 272253
AFDBOX

Area Forecast Discussion
National Weather Service Taunton MA
653 PM EDT FRI MAY 27 2016

.SYNOPSIS...
Humid weather continues tonight with any lingering showers
diminishing but fog possible overnight. A backdoor cold front
will bring cooler temperatures to eastern MA Sunday but it will
remain very warm across the interior, where scattered showers and
thunderstorms likely develop during the afternoon. The potential
exists for a period of heavy rain very late Sunday night into
Memorial Day. Dry weather likely follows Tuesday through Thursday,
with above normal temperatures trending back to seasonable levels
by late in the week. A cold front approaches on Friday with a
chance of showers.

&&

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

The remaining showers should diminish this evening. Concern now
turns to fog formation overnight. Current dew points 55 to 65
while water temps east and south are in the 50s. Satellite imagery
continues to show fog along the Maine coast and farther offshore.

With light winds and increasing moisture in the air, we are likely
to have another round of fog. This will favor coastal areas as
well as typical inland fog spots. The fog may be locally dense,
and may require a dense fog advisory once confidence is higher in
its location.

Otherwise, mins only fall into the low-mid 60s again tonight
thanks to high crossover temps and lingering clouds.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
Tomorrow...
Mid lvl ridging continues with rising heights across the region
and plenty of sunshine. No trouble mixing to at least H85 where
temps will approach +16C by afternoon peak heating. Weak return
flow will limit sea breezes to mainly the south coast.
Therefore, still expecting probably the hottest day we have seen
thus far with highs topping out in the low-mid 90s across much of
the region away from S coastal areas. Dwpts will remain elevated
as well, mainly in the low-mid 60s even during peak mixing.

The other issue will be convective potential. Plenty of SFC/mixed
lvl CAPE would be available, except the rising heights and modest
subsidence it/s associated with is likely to yield a slight
capping inversion and limit updraft development. Lapse rates are
modest, mainly approaching 6.0C/KM in the mid lvls, but this is
most likely a reflection of the mid lvl dry air. Even the latest
12Z ECMWF now is almost NIL for QPF during the afternoon and
evening hours. Definitely not going NIL given the rising PWATs and
potential energy available if the cap is broken, but will limit it
mainly to slight and low end chance across the terrain and along
developing sea breezes where at least some lift will be available.
T-storms will be mainly airmass-type as shear is also quite
limited.

Tomorrow night...
Continued increase in low-mid lvl moisture will actually help to
erode the cap and allow for some maintenance of any shra/t-storms
that develop, so will be slow to drop overnight POPs. Otherwise,
the increase in moisture beneath the inversion increases the risk
for overnight fog development which once again has the risk of
being locally dense at times and may require headlines. Otherwise,
another mild night with mins only falling back into the 60s.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
Big Picture...

Longwave scale shows East Coast upper ridge over the weekend. The
ridge axis shifts west and deamplifies Sunday and Monday. Pattern
shifts to ridge West and trough East during mid to late week.

Shortwave scale shows East Coast ridge Sunday shifting out to sea
and opening a moist flow up the coast from a disturbance off
Florida. All models hold some of this disturbance off the SE
USA coast early week while sending pieces of it up the coast and past
New England early week. Timing of these pieces remains in question
but model consensus would point to Monday-Monday night passage.
Northern jet stream shows one shortwave racing past New England
Monday night, and a second approaching next Friday.

Details...

Sunday...

Maritime high pressure builds and pushes a backdoor front into
Southern New England.  With the upper ridge shifting overhead the
surface front will at some point be parallel to the upper flow and
may stall over the region. Stability parameters such as the Total-
Totals and the Lifted Index become marginally unstable by the
afternoon across Western and Central MA. Any sunshine heating this
airmass together with the low level convergence along the front may
lead to thunderstorm development. Best chance would be in
Western/Central MA, but this could expand across Northern CT as
well depending on placement of the backdoor front.  Precipitable
water values near 1.5 inches, well above the May 29 average of 0.88,
suggest some potential for local heavy downpours.

The backdoor front shifts north Sunday night plunging our area more
fully into mild and humid air.

Temperatures at the top of the mixed layer are expected to be equiv
to 15-16C at 850 mb. Full mixing of this would support highs in the
80s. East/marine flow on the cool side of the backdoor front may
keep temps in Eastern MA in the 70s.  Increasing clouds and dew
points of 55 to 65 should keep Sunday night temps no lower than 55 to
65.

Monday...

Surface low pressure, part of the system off the SE USA coast, moves
up the coast and spreads a good supply of moisture into New England.
The coastal low will bring some dynamic support for lift. At the
same time, a shortwave moves east from the Great Lakes and drives a
cold front toward New England. This shortwave will move New England
under the lift-friendly right entrance region of its upper jet.  It
will also draw plenty of moisture north with precipitable water
values at 1.75 inches and potentially near 2 inches. As with the
Sunday values, this is well above normal for the Memorial Day
weekend. This will mean more showers, scattered thunder, and some
locally heavy downpours. Much of the concern for Monday will be
the developing potential for local flooding from any heavy
downpours.

Tuesday through Friday...

High pressure brings drier air in on Tuesday and lingers through the
week. Westerly winds Tuesday will allow temps to reach the low to
mid 80s. Later in the week, as the high shifts offshore and the
surface flow becomes south to southeast, max temperatures will be
held to the 70s with some 60s at the coast.

By Friday a cold front in the St Lawrence Valley will bring showers
in New York and Northern New England. The question will be if any of
those showers can reach Southern New England. For now we will go
with consensus values with slight chance pops during the day and
chance pops in some locations Friday night. This timing will likely
change.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
Forecaster Confidence Levels.

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

Tonight...moderate confidence. Mainly VFR through about 06Z
inland, then patchy fog possible especially at typically prone
airports with localized MVFR/IFR conditions. Another risk for LIFR
along Cape Cod and Island terminals overnight into Saturday morning.

Saturday and Saturday night...moderate confidence.
Mainly VFR. Local MVFR-IFR conditions in patchy fog through mid
morning. Low probability of brief MVFR conditions in SCT afternoon
SHRA/TSRA across the interior. Another risk for overnight fog
tomorrow night.

KBOS TAF...High confidence in TAF.

KBDL TAF...High confidence in TAF.

Outlook /Sunday through Wednesday/...

Sunday...Moderate Confidence.

VFR. Areas of MVFR in afternoon showers and scattered thunderstorms.

Sunday night-Monday...Moderate confidence.

Conditions lowering to MVFR and IFR in fog overnight. MVFR-IFR
conditions in showers late Sunday night through Monday. Locally
heavy downpours. Winds become east Sunday night and South on Monday.

Tuesday-Wednesday...Moderate to high confidence.

VFR conditions except local IFR in fog each late night and
morning.

&&

.MARINE...
Forecaster Confidence Levels.

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

Short Term /through Saturday Night/...High confidence.

Tonight...
Winds and seas remain uneventful tonight. There will be some fog
to contend with. The fog could be quite dense at times and may
take some time to burn off even after sunrise.

Saturday and Saturday night...
Seas on the southern outer waters may briefly reach 5 feet at
times but should diminish again at night. South to southwest winds
will remain less than 20 knots. More fog may develop Saturday
night.

Outlook /Sunday through Wednesday/...

Sunday...High confidence.

Winds and seas remain less than Small Craft Advisory thresholds.
Locally poor vsbys in fog Sunday morning.

Sunday night-Monday...Moderate confidence.

Winds and seas increase but still remain below SCA thresholds. Areas
of poor vsbys in rain and fog.

Monday night through Wednesday...

Seas build to 5-6 feet on the exposed Southern Waters Monday night
and Tuesday. South winds near 20 knots early Monday night shift out
of the West and diminish overnight. Winds remain below SCA
thresholds through Wednesday.  A Small Craft Advisory may be needed
for hazardous seas Monday night and Tuesday.

&&

.CLIMATE...
Still expect highest temperatures of the week on Saturday. Some
record highs may be challenged. However, might even see temps
getting close to records today as well.

Record highs for Saturday May 28...

Boston...92 set in 1931
Providence...91 set in 1931
Hartford...93 set in 1977
Worcester...88 set in 1911 and 1929
Milton/Blue Hill...90 set in 1929

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...Air Quality Alert from 11 AM to 11 PM EDT Saturday for CTZ003-
     004.
     Air Quality Alert until 11 PM EDT this evening for CTZ002>004.
MA...Air Quality Alert from 11 AM to 11 PM EDT Saturday for
     MAZ004>007-009>018-026.
     Air Quality Alert until 11 PM EDT this evening for MAZ002>006-
     008>013-026.
RI...Air Quality Alert until 11 PM EDT this evening for RIZ001>005.
MARINE...None.

&&

$$
SYNOPSIS...WTB/Doody
NEAR TERM...WTB/Doody
SHORT TERM...Doody
LONG TERM...WTB
AVIATION...WTB/Doody
MARINE...WTB/Doody
CLIMATE...





000
FXUS61 KBOX 271928
AFDBOX

Area Forecast Discussion
National Weather Service Taunton MA
328 PM EDT FRI MAY 27 2016

.SYNOPSIS...
Hot and hazy conditions continue with a low risk for showers or
thunderstorms late today and again late tomorrow. A backdoor cold
front will bring cooler temperatures to eastern MA Sunday but it
will remain very warm across the interior, where hit and miss
showers and thunderstorms likely develop during the afternoon. The
potential exists for a period of heavy rain very late Sunday night
into Memorial Day. Dry weather likely follows Tuesday through
Thursday, with above normal temperatures trending back to
seasonable levels by late in the week.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
A very warm and hazy day continues thanks to modest but apparent
mid lvl ridging across srn New England. Upstream, noting a CU
field and some shra/t-storms developing where airmass is more
unstable /cooler aloft and more moist in the low lvls/. This is
not expected to push much further E than the Berkshires through
the evening, as the more stable/capped airmass remains in place
across our region. Still have a few slight chance pops for this
risk.

Overnight, expect another mild and partly cloudy night with the
remnant clouds from upstream convection moving over during the
early morning hours. Noting current dewpoints vs SSTs still in the
50s, and an area of stratus/fog in the Gulf of Maine per latest
VIS imagery, will likely see another round of fog especially
along coastal areas /SE MA again/ and more areas inland overnight.
This could once again be locally dense, and may require a dense
fog advisory once confidence is higher in its location.

Otherwise, mins only fall into the low-mid 60s again tonight
thanks to high crossover temps and lingering clouds.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
Tomorrow...
Mid lvl ridging continues with rising heights across the region
and plenty of sunshine. No trouble mixing to at least H85 where
temps will approach +16C by afternoon peak heating. Weak return
flow will limit sea breezes to mainly the south coast.
Therefore, still expecting probably the hottest day we have seen
thus far with highs topping out in the low-mid 90s across much of
the region away from S coastal areas. Dwpts will remain elevated
as well, mainly in the low-mid 60s even during peak mixing.

The other issue will be convective potential. Plenty of SFC/mixed
lvl CAPE would be available, except the rising heights and modest
subsidence it/s associated with is likely to yield a slight
capping inversion and limit updraft development. Lapse rates are
modest, mainly approaching 6.0C/KM in the mid lvls, but this is
most likely a reflection of the mid lvl dry air. Even the latest
12Z ECMWF now is almost NIL for QPF during the afternoon and
evening hours. Definitely not going NIL given the rising PWATs and
potential energy available if the cap is broken, but will limit it
mainly to slight and low end chance across the terrain and along
developing sea breezes where at least some lift will be available.
T-storms will be mainly airmass-type as shear is also quite
limited.

Tomorrow night...
Continued increase in low-mid lvl moisture will actually help to
erode the cap and allow for some maintenance of any shra/t-storms
that develop, so will be slow to drop overnight POPs. Otherwise,
the increase in moisture beneath the inversion increases the risk
for overnight fog development which once again has the risk of
being locally dense at times and may require headlines. Otherwise,
another mild night with mins only falling back into the 60s.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
Highlights...

* Turning cooler Eastern MA coast Sunday but still very warm
  inland

* Hit and miss showers/t-storms likely across interior southern
  New England Sunday afternoon/early evening

* Period of heavy rain possible very late Sunday night into
  Memorial Day with even a small risk of localized flooding

* Dry weather Tue into Thu with above normal temps trending back
  to seasonable levels late in the week

Details...

Saturday night...Isolated to widely scattered showers/t-storms may
linger into the evening but should be on the downward trend with the
loss of daytime heating.  Otherwise, expect mainly dry weather
Saturday night but it will be quite mild and muggy for late May. Low
temps may only drop into the middle to upper 60s for many locations
away from the cooling marine influence of the south coast.  Patchy
fog likely develops in the typically prone locations with dewpoints
in the 60s.

Sunday...Still timing differences with the backdoor cold front but
appears that it will still be east of the CT River Valley by mid
afternoon.  So its conceivable that Sunday afternoon temps will have
fallen into the 60s along the Eastern MA coast, while the Lower CT
River Valley might be in the lower 90s.  The morning should mainly
be dry, but expect 1000 to 2000 J/KG of Cape to develop across
interior southern New England.  Despite upper level ridging, decent
low level convergence/instability will allow low level moisture to
pool a bit. The result should be hit and miss showers/thunderstorms
developing across interior southern New England Sun afternoon. The
extent of this activity will be determined by how fast the front
moves and amount of instability that is able to develop.  Highest
risk for scattered activity is across western MA/northern CT but it
could extend back into portions of central MA/RI if front moves
slower.  0 to 6 km shear is weak, so overall severe weather threat
is low.  However, given decent instability can not rule out a strong
thunderstorm or two. Any storms that develop will be slow moving and
capable of producing very localized heavy rain.

So to sum up Sunday, dry weather expected for much of the day but
scattered showers/t-storms likely develop in the afternoon across
the interior.  While activity should be hit and miss, very localized
heavy rainfall and lightning will be the biggest concern with any
storm.

Sunday night and Memorial Day...

Hit and miss convection across the interior should diminish Sunday
evening with the loss of daytime heating.  Mainly dry weather
expected for the first part of the night.

Things then become very interesting very late Sunday night into
Memorial day. The National Hurricane Center is expecting low
pressure between the Bahamas and Bermuda to develop into a
tropical or sub tropical cyclone in the next 48 hours. While a
direct impact will not occur, an approaching cold front will
likely pull a plume of its tropical moisture northward. PWATS may
rise to around 2 inches in southern New England. Still plenty of
uncertainty on how this unfolds, but a period of heavy rain
showers and a few embedded thunderstorms are possible across the
region. Fortunately, this appears to be a progressive event but
given tropical connection there is a small risk of some localized
flooding. Something will have to watch closely, especially given
it will be on the end of a Holiday Weekend and a big travel day.

Tuesday through Thursday...

Looks like dry and warm weather follows behind the cold front on
Tuesday with highs mainly in the 80s.  It is a long way off, but
current guidance favors dry weather Wed into Thu as high pressure
builds down from the Canadian Maritimes.  This would also generate
an easterly low level component to the wind with temperatures likely
returning to seasonable normals by Thursday.

&&

.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
Forecaster Confidence Levels.

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

Through 00z...high confidence.
VFR conditions continue with a low risk for afternoon
shra/t-storms mainly across the CT valley and points W.

Tonight...moderate confidence.
Mainly VFR through about 06Z inland, then patchy fog possible
especially at typically prone airports with localized MVFR/IFR
conditions. Another risk for LIFR along Cape Cod and Island
terminals overnight into tomorrow morning.

Saturday and Saturday night...moderate confidence.
Mainly VFR. Local MVFR-IFR conditions in patchy fog through mid
morning. Low probability of brief MVFR conditions in SCT afternoon
SHRA/TSRA across the interior. Another risk for overnight fog
tomorrow night.

KBOS TAF...High confidence in TAF.

KBDL TAF...High confidence in TAF.

Outlook /Sunday through Wednesday/...

Sunday...Moderate confidence.  VFR conditions may lower to MVFR
thresholds across Eastern New England behind backdoor cold front.
Otherwise, mainly VFR across the interior but briefly lower
conditions possible in hit and miss showers/t-storms during the
afternoon.

Sunday night and Memorial Day...Moderate confidence.  MVFR-IFR
conditions may develop late Sunday night into Memorial Day in a
period of rain showers which may be locally heavy.

Monday night and Tuesday...Moderate to high confidence in mainly
VFR conditions.

&&

.MARINE...
Forecaster Confidence Levels.

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

Short Term /through Saturday Night/...High confidence.

Will be dropping the small craft advisory as it appears seas will
generally not build as high as previously forecast. Winds still
remain mostly S-SW with gusts only to around 20 kt near shore
during the daylight hours. Therefore, mainly quiet boating weather
is expected regarding mainly seas and winds.

There will be some fog to contend with especially overnight and
morning hours. This could be quite dense at times and may take
some time to burn off even after sunrise.

Outlook /Sunday through Wednesday/...High confidence.

Winds and seas will generally remain below small craft advisory
through the period with a relatively weak pressure gradient.
Biggest concern for Mariners will be late Sunday night into
Memorial Day, when a period of heavy rain showers/isolated
thunderstorms are possible.

&&

.CLIMATE...
Still expect highest temperatures of the week on Saturday. Some
record highs may be challenged. However, might even see temps
getting close to records today as well.

Record highs for Saturday May 28...

Boston...92 set in 1931
Providence...91 set in 1931
Hartford...93 set in 1977
Worcester...88 set in 1911 and 1929
Milton/Blue Hill...90 set in 1929

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...Air Quality Alert until 11 PM EDT this evening for CTZ002>004.
MA...Air Quality Alert until 11 PM EDT this evening for MAZ002>006-
     008>013-026.
RI...Air Quality Alert until 11 PM EDT this evening for RIZ001>005.
MARINE...None.

&&

$$
SYNOPSIS...WTB/Doody
NEAR TERM...Doody
SHORT TERM...Doody
LONG TERM...WTB
AVIATION...WTB/Doody
MARINE...WTB/Doody
CLIMATE...staff





000
FXUS61 KBOX 262300
AFDBOX

Area Forecast Discussion
National Weather Service Taunton MA
700 PM EDT THU MAY 26 2016

.SYNOPSIS...
Warm weather will continue through Saturday, except at times
along the immediate coast. A backdoor cold front will bring cooler
weather to eastern MA Sunday with warm weather continuing
elsewhere. Dry weather dominates through Sunday other than
isolated showers/thunderstorms at times, then a period of more
widespread showers are possible Monday. Above normal temperatures
continue through midweek then turning cooler toward the end of the
week.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
7 pm update...
A few showers developed along the sea breeze boundary from
southern NH into northeast MA but this activity is diminishing.
HRRR is indicating a few showers tonight across northern MA as
weak shortwave moves through. Current forecast on track.

Previous Discussion...
Mid level ridge sinks south a bit but overall conditions remain
the same as previous couple of days. Winds will keep an onshore
direction overnight so with sea surface temperatures in the mid to
upper 50s, expect low temperatures in the same range along the
coast. Temperatures will be warmer farther inland, with lows in
the low 60s expected.

A very weak shortwave will move through the westerly mid-level flow.
This could result in a few showers occurring during the night. Think
this will be very spotty and while there is enough instability for
thunder to be possible, don`t think it will be frequent or common.
Continued slight chance to very low end chance pops mainly for the
western zones.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
Friday...Mid level ridge continues to be the main influence of our
weather.  It will be another warm day for much of the area with
southerly winds.  The pressure gradient is a little tighter, so we
may get away without a sea breeze developing on the east coast.  The
south coast will be the larger concern with southerly winds keeping
temperatures along the coast cool.  Expect high temperatures into
the mid to upper 80s for most locations away from the south coast.

A pre-frontal trough will move into southern New England during the
day which could result in some convection.  However, there are some
limiting factors, including rising heights, that will limit this
potential somewhat. There will be enough instability generated
during the day as well as elevated instability for thunder to
develop.  Again, think this will be rather spotty and isolated for
the most part.

Friday night...Any isolated convection that does occur will diminish
during the evening hours.  Then dry weather is expected.  Low
temperatures are expected to be in the 60s.  With dewpoints in the
upper 50s to lower 60s, patchy ground fog will likely develop in the
typically prone locations.

&&

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

* Hot Sat w/highs mainly 90-95 in the interior, cooler coast
* Cooler Sun east coastal MA but continued very warm further in the
  interior
* Mainly dry Sat/Sun other than iso showers/t-storms in the interior
* More widespread showers may affect the region Mon then mainly dry
  for the rest of the week
* Above normal temperatures through midweek then turning cooler

Details...

Saturday...
Hot and increasingly humid conditions as anomalous mid level ridge
builds across New Eng.  850 temps up to 17C will result in highs 90-
95 degrees in the interior, mainly west of I-95 corridor. SW flow
off cooler SST will yield cooler temps in the SE coastal plain and
especially along the south coast as mixing is more shallow and
cooler 925 mb temps noted. Expect highs in the 80s coastal plain
with 70s along the immediate south coast and Cape/Islands.

The hot temps and increasing dewpoints will destabilize the
atmosphere with CAPEs 1000-2000 J/kg developing in the interior.
However, there are limiting factors with building mid level ridge
and anticyclonic flow which will serve to suppress activity in the
absence of notable synoptic forcing. And mid levels will be fairly
dry. Most of SNE should remain dry but can`t rule out a few
showers/t-storms across northern and western MA into western CT
late in the day into Sat evening. Severe threat is low given
weakly sheared environment, but if any convection develops there
is potential for gusty winds with decent instability and inverted
V sounding profile.

Sunday...
Timing of a backdoor cold front remains very uncertain which will
significantly impact temps. GFS is most aggressive moving the front
through much of SNE by morning while NAM/ECMWF are much slower and
keep much of the region in the very warm air. Will continue the
theme of the previous forecast indicating cooler air moving into
eastern MA with temps mostly in the 70s, but warmer 80s further west
and especially CT Valley where temps may approach 90 again if
front is delayed. This is not a high confidence temp forecast as
a 6 hour change in timing will make a big difference. Models
generating 1000-2000 J/kg of SBCAPE west of the boundary so a few
showers/t-storms possible ahead of the front, mainly central/W New
Eng but this will be dependent on the timing and location of the
front. Deep layer shear remains weak so severe threat is low.

Monday...
Models indicate a mid level shortwave moving through as a plume of
tropical moisture surges northward ahead of possible tropical
disturbance to the south. Models indicate PWATs increasing to near 2
inches with marginal instability developing, depending on extent of
cloud cover. This may lead to more widespread showers and sct t-
storms with locally heavy rainfall possible. Confidence on how this
plays out is not high but the potential exists for wet weather. Temps
will be dependent on extent of clouds/showers but a cooler day is
likely.

Tuesday through Thursday...
Deep moisture plume will be exiting the region by Tue as a cold
front moves offshore with significant decrease in PWATs. Looks
mainly dry Tue although if front is slower, shower threat could
linger. Then mainly dry Wed/Thu as high pres builds in from the N.
Temps cooling mid to late week as easterly flow develops.

&&

.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
Forecaster Confidence Levels.

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

Tonight...High confidence. VFR conditions likely for much of the
period. Low probability of brief MVFR conditions in SCT -SHRA/-TSRA
mainly across W MA/N CT.

Friday...High confidence. Mainly VFR. Low probability of brief
MVFR conditions in SCT -SHRA/-TSRA mainly across the interior.

Friday night...High confidence. Mainly VFR. Patchy ground fog
develops resulting in patchy MVFR/IFR conditions.

KBOS TAF...High confidence in TAF.

KBDL TAF...High confidence in TAF.

Outlook /Saturday through Tuesday/...

Saturday...High confidence. Mainly VFR other than a few hours of
patchy ground fog toward daybreak Sat in the typically prone
locations. Isolated late day/evening showers/t-storms possible
distant interior.

Sunday...Moderate confidence. Mostly VFR but patchy MVFR cigs
possible eastern MA depending on location of backdoor front.
Widely scattered showers/t-storms possible interior.

Monday...Low confidence. Potential for a period of MVFR-IFR
conditions in low clouds and showers/t-storms.

Tuesday...Moderate confidence. Mainly VFR, but lower conditions
possible in the morning especially near the coast.

&&

.MARINE...
Forecaster Confidence Levels.

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

Short Term /through Friday Night/...High confidence.

High confidence.  Quiet boating weather is expected through the
short term.  There is a low probability of seas reaching 5 feet on
the outer waters Friday night.  Winds will generally be out of the
south.  Fog may develop over the waters Friday night, limiting
visibilities.

Outlook /Saturday through Tuesday/...High confidence.

Winds and seas will generally remain below small craft advisory
thresholds through the period, but there may be a period of SW
gusts approaching 25 kt on Monday over nearshore waters.

&&

.CLIMATE...
Warmest day of the week appears to be Saturday and some record
highs may be challenged.

Record highs for Saturday May 28...

Boston...92 set in 1931
Providence...91 set in 1931
Hartford...93 set in 1977
Worcester...88 set in 1911 and 1929
Milton/Blue Hill...90 set in 1929

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...Air Quality Alert until 11 PM EDT this evening for CTZ002>004.
     Air Quality Alert from 11 AM to 11 PM EDT Friday for
     CTZ002>004.
MA...Air Quality Alert until 11 PM EDT this evening for MAZ002>005-
     008>014-017-018-020-021-023-026.
RI...Air Quality Alert until 11 PM EDT this evening for RIZ001>008.
MARINE...None.

&&

$$
SYNOPSIS...KJC/RLG
NEAR TERM...KJC/RLG
SHORT TERM...RLG
LONG TERM...KJC
AVIATION...KJC/RLG
MARINE...KJC/RLG
CLIMATE...





000
FXUS61 KBOX 260854
AFDBOX

Area Forecast Discussion
National Weather Service Taunton MA
454 AM EDT THU MAY 26 2016

.SYNOPSIS...
Very warm to hot weather will continue through Saturday, but it
will be a bit cooler at times on the immediate coast. A backdoor
cold front will bring cooler weather to eastern MA Sunday with
warm weather continuing elsewhere. Dry weather dominates through
Sunday other than isolated showers/thunderstorms at times. Near or
above normal temperatures continue for much of next week and there
is the potential for a period of more widespread showers Monday
and/or Tuesday.

&&

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

Patchy high clouds continue to stream across the region early
this morning as seen on latest IR satellite imagery. Also noting
some patchy fog across N central MA in the normally susceptible
valleys, as temps have fallen to the lower-mid 50s close to dewpt
values at 08z.

As high pressure ridge builds S of the region, expect a general
light pressure gradient. This will allow sea breezes to develop
along the coast by late morning through the mid to late afternoon.
H5 ridging also builds E today, with H5 heights increasing to 580
to 582 dm by this afternoon. With W-SW winds aloft, H85 temps will
increase to +14C to +16C this afternoon, and up to +22C across
western areas at H925! Very warm airmass indeed.

Expect temps to rise to 85-90 away from the coast, but held down
to the 70s to around 80 along the immediate coast with the sea
breezes. Temps may rise quickly late this afternoon as the sea
breeze kicks out, so readings may rise there as well /from about
Marshfield and Boston northward with W winds/.

With the slow moving or stalling weak front across the region, there
may be just enough lift along with the diurnal heating and marginal
instability to cause some airmass showers/thunderstorms to develop
this afternoon across central and western interior areas. Not
expecting widespread activity, but can not rule out spotty
convection. Have slight chance POPs going there.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...

Tonight...The weak stalled front should also lift N-NE as winds
become more S-SW and the ridge pushes offshore. Noting a weak mid
level short wave in the SW flow at the surface and aloft. Some
timing issues on the short range models in moving this E out of
the Appalachians and mid Atlc states. Have kept similar timing
going from the previous forecast and kept mention of slight chance
to low chance POPs, with only an isolated mention of thunder,
though think this will be very spotty.

With ocean temps mainly in the lower-mid 50s and the onshore
winds, expect overnight lows to fall back to 55-60 across eastern
and central areas, ranging to the lower-mid 60s across the CT
valley.

Friday...Expect another warm day with continued S-SW winds on
back side of high pres ridge over the western Atlc. With the high
in place to the E, weak trough will remain across western areas.
Also noting rather good instability with CAPEs rising to 1200-1400
J/kg as well as K indices in the low-mid 30s and surface based LIs
on around -1 to -2. So have kept chance POPs going from the
interior Merrimack valley across central MA to the CT valley, with
the best shot from late Friday morning through the afternoon.
Temps will be in the 80s away from the immediate coast, holding in
the 70s along S coastal areas with the onshore winds.

&&

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

* Hot Sat w/highs mainly 90-95 away from the immediate coast.

* Near or above normal temperatures through much of next week

* Mainly dry Sat/Sun other than iso showers/t-storms but activity
  could be a bit more organized Sun afternoon across interior

* Its possible a more widespread area of showers affects the region
  Mon and/or Tue but that remains highly uncertain

Details...

Friday night...While it remains uncertain if any isolated convection
will affect the region late Friday it should diminish during the
evening hours. Otherwise, dry weather with upper level ridging in
control. Low temps will only drop to between 60 and 65 in most
locations.  Some patchy ground fog will likely develop in the
typically prone locations given increasing low level moisture.

Saturday...Unseasonably hot weather anticipated across most of our
region.  850T around +16c with plenty of sunshine and a well mixed
atmosphere should yield highs between 90 and 95 in most locations
away from the immediate coast where localized sea breezes may
develop.  Dewpoints in the lower to middle 60s will make it feel a
bit muggy.

The majority of Saturday will be dry, but there is the risk for some
isolated to widely scattered convection Saturday afternoon and
evening.  As usual, mesoscale processes will dictate what happens
and its not clear cut. A weak pre-frontal trough will combined with
modest instability with Capes increasing to between 1000 and 2000
J/KG. Upper level ridging and lack of forcing will certainly be
limiting factors.  Sea breeze convergence and terrain impacts might
be enough to trigger isolated to widely scattered convection Sat
afternoon and evening. 0 to 6 KM shear is weak, so if anything
develops the overall severe weather threat would be low.
However, an isolated strong thunderstorm or two can not be ruled out
with decent instability and potentially large temp/dewpoint spreads.
Very localized heavy rainfall would also also be possible given any
storm that is able to develop will be slow moving.

In a nutshell, much of the region will likely remain dry Saturday
but isolated slow moving showers/t-storms with very localized heavy
rainfall can not be ruled out.

Sunday...

The backdoor cold front pushes across the region from east to west.
Timing of the front remains uncertain and a 6 hour shift in either
direction will make a huge difference in high temperatures. Overall,
thinking interior gets very warm while cooler air works into Eastern
MA.  A few showers may accompany the cold front, but will have to
watch for a bit more organized area of scattered
showers/thunderstorms with very localized heavy rainfall across
Western MA/Northern CT Sunday afternoon. This will depend upon how
much instability develops ahead of the backdoor front and its exact
timing.

Monday and Tuesday...

A disturbance currently northeast of the Bahamas will track
northwest and probably not directly impact our region.  However, a
plume of its tropical moisture may get pulled north into southern
New England ahead of a cold front.  Low confidence on how this all
plays out, but there is at least a risk for a more
organized/widespread area of rain showers.  Temps will remain near
or above normal and exact temps be determined by timing of potential
clouds/showers.

Wednesday...

Low confidence this far out but do not see any organized
precipitation threats.  Temps near or above normal.

&&

.AVIATION /09Z THURSDAY THROUGH MONDAY/...
Forecaster Confidence Levels.

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

Short Term...

Through 12Z...High confidence. VFR. Patchy fog with local MVFR-
IFR CIGS/VSBYS across interior valleys. Light W-SW or calm winds
shift to W-NW across N MA.

Today...High confidence. VFR. Expect sea breezes to develop by
mid to late morning on both coasts, lasting through mid to late
afternoon.

Tonight...Moderate confidence. VFR conditions likely for much of
the period. Brief MVFR conditions possible in SCT -SHRA/-TSRA
mainly across W MA/N central CT, but briefly may reach into NE
CT/central MA this evening. Patchy fog with MVFR-IFR conditions
after 07Z-08Z across interior valleys.

Friday...Moderate to high confidence. Mainly VFR. Local MVFR
conditions with low risk of a few brief scattered SHRA/TSRA mainly
across the interior. Also, patchy ground fog possible in the
typically prone locations through mid morning.

KBOS TAF...High confidence in TAF.

KBDL TAF...High confidence in TAF.

Outlook /Friday Night through Monday/...

Friday night and Saturday...Moderate to high confidence.  Mainly VFR
other than a few hours of patchy ground fog toward daybreak Sat in
the typically prone locations.  Isolated showers/t-storms may also
result in brief/localized lower conditions.

Sunday...Low to moderate confidence. May see some MVFR CIGS work
into northern and eastern MA behind the backdoor cold front.
Otherwise, mainly VFR outside of any widely scattered convection.

Monday...Low confidence.  Potential for a period of MVFR-IFR
conditions in low clouds and some showers but that remains highly
uncertain.

&&

.MARINE...
Forecaster Confidence Levels.

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

Short Term /through Friday/...High confidence.

Today and tonight...Expect S-SE winds less than 15 kt and seas 4
ft or less. May see some visibility restrictions in patchy fog
late tonight along the coast.

Friday...S-SW winds 15 kt or less. Some gusts may approach 20 kt
on the near shore waters during the afternoon. Seas remain 4 ft or
less. May see local visibility restrictions in patchy early
morning fog.

Outlook /Friday Night through Monday/...High Confidence.

Winds and seas will generally remain below small craft advisory
thresholds through the period.  Biggest concern is Saturday
afternoon along the south coast...where some near shore lower 20
knot wind gusts may occur resulting in choppy seas.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...Air Quality Alert from 11 AM this morning to 11 PM EDT this
     evening for CTZ002>004.
MA...Air Quality Alert from 11 AM this morning to 11 PM EDT this
     evening for MAZ002>005-008>014-017-018-020-021-023-026.
RI...Air Quality Alert from 11 AM this morning to 11 PM EDT this
     evening for RIZ001>008.
MARINE...None.

&&

$$
SYNOPSIS...Frank/EVT
NEAR TERM...EVT
SHORT TERM...EVT
LONG TERM...Frank
AVIATION...Frank/EVT
MARINE...Frank/EVT





000
FXUS61 KBOX 260638
AFDBOX

Area Forecast Discussion
National Weather Service Taunton MA
238 AM EDT THU MAY 26 2016

.SYNOPSIS...
High pressure off the mid Atlantic coast will bring very warm
weather to most of the region through Saturday, along with
increasing humidity. It will be cooler at times along the
immediate coast. A backdoor cold front will bring cooler weather
to Rhode Island and eastern Massachusetts Sunday with warm weather
continuing elsewhere. Warmer than normal temperatures overspread
the remainder of the area by early next week. A few showers and
thunderstorms are possible Thursday night into Friday, and again
this weekend but the vast majority of the time will be dry.

&&

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

210 AM Update...

Leading edge of high clouds moving into portions of the CT valley
at 06Z as seen on latest IR satellite imagery, well ahead of
approaching H5 short wave in the general W flow aloft. A weak, dry
cold front pretty much stalled across S VT/NH into S coastal ME.
Little if any moisture with this system, so will remain dry
through sunrise.

Temps remain warm across the region early this morning, mainly in
the mid-upper 50s across N central and W MA, ranging to around 70
in the urban centers at 06Z. May see some patchy fog develop
through around 12Z as temps fall close to the dewpts across the
normally susceptible inland valley locations, especially the mid
CT valley in MA.

Have updated near term forecast to bring conditions current.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM FRIDAY/...

Today...High pressure moves offshore slowly while the mid level
ridge centers itself over southern New England. With a much weaker
gradient over the region, sea breezes along both coasts are a slam
dunk. Therefore, temperatures will be cooler at the coasts but
still in the mid to upper 80s for the rest of the area under
mostly sunny skies.

Tonight...Mid level ridge sinks south a bit but overall
conditions remain the same as previous couple of days. Winds will
go calm overnight allowing temperatures to drop back into the
upper 50s to lower 60s for most places.

&&

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
350 pm update...

Highlights...

* Temperatures warmer than normal much of the time

* Other than isolated showers/thunderstorms many hours of dry
  weather this period

Subtropical ridge builds northwestward from western Atlantic into
the northeast late this week into the weekend and lingers into at
least early next week. This will result in temperatures warmer
than normal much of the time along with mainly dry weather. Both
the 00z GEFS and 00z EPS offer 850 temp anomalies of +1 to +2
standard deviations above normal over southern New England during
this time. However there will be a brief cool down Sunday across
eastern MA and RI as a shallow cool airmass invades this area
behind a backdoor cold front. Otherwise much of this forecast
period will be warmer than normal (normal highs around 70, normal
lows around 50).

As for rain chances...a prefrontal trough will enter western
portions of MA and CT Friday. However rising heights and
increasing anticyclonic mid level flow will likely suppress most
convective development. Likewise on Sat with the ridge continuing
to build and heights reaching +2 standard deviations above normal
over the northeast. By late Sat and into Sunday the backdoor front
provides surface convergence and shallow low level forcing first
north of MA Sat and then across much of the region Sunday. However
large amplitude ridge over the region along with mid level
anticyclonic flow may suppress much of the convection once again.
Thus model guidance is likely too wet especially the 12z GFS.
Therefore have undercut guidance from chance to slight chance pops
Fri/Sat and Sun. Greatest risk (albeit low) of seeing any
showers/thunderstorms Fri/Sat & Sunday will likely be across
western portions of MA and CT. Thus a washout is not expected
just isolated to widely scattered showers/thunderstorms well
inland.

Mon and Tue of next week become interesting as area of convection
currently northeast of the bahamas advects northwestward around
the subtropical ridge into the mid Atlantic region. Then it
becomes a question if the upstream northern stream trough has
sufficient amplitude to capture this area tropical moisture and
advect it into southern New England. 00z GEFS and 00z EPS both
suggest bulk of tropical moisture remains offshore or just clips
south coast of New England and bulk of convection from northern
stream trough remains northwest across NY state and VT. Given the
time range and uncertainty chance pops seems reasonable here.

&&

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
Forecaster Confidence Levels.

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

Through 12Z...High confidence. VFR. Patchy fog with local MVFR-IFR
CIGS/VSBYS across interior valleys through 12Z. Light W-SW or
calm winds shift to W-NW across N MA.

Today...High confidence. VFR. Expect sea breezes to develop by mid
to late morning on both coasts, lasting through mid to late
afternoon.

Tonight...Moderate confidence. VFR conditions likely for much of
the period. Brief MVFR conditions possible in SCT -SHRA/-TSRA
mainly across W MA/N central CT, but briefly may reach into NE
CT/central MA this evening. Patchy fog with MVFR-IFR conditions
after 07Z-08Z across interior valleys.

Friday...Moderate to high confidence. Mainly VFR. Local MVFR
conditions with low risk of a few brief scattered SHRA/TSRA
mainly across the interior. Also, patchy ground fog possible in
the typically prone locations through mid morning.

KBOS TAF...High confidence in TAF.

KBDL TAF...High confidence in TAF.

Outlook /Friday Night through Monday/...

Friday night...Moderate to high confidence. Leftover MVFR
conditions in isolated SHRA/TSRA in the evening, then mainly VFR.
May see late night patchy fog with local MVFR-IFR conditions.

Saturday...Moderate to high confidence. Any early MVFR conditions
should quickly lift to VFR by midday. Low risk of a few afternoon
and evening showers/thunderstorms well inland.

Sunday...Moderate confidence. MVFR likely with low risk of IFR in
spots. A few thunderstorms also possible Sun afternoon across the
interior.

Monday...Low confidence given time range and weather pattern. VFR
likely but period of MVFR in low risk of scattered showers/
thunderstorms.

&&

.MARINE...
Forecaster Confidence Levels.

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

High confidence. Winds and seas below small craft criteria
through Thursday night.

Outlook /Friday Night through Monday/...High Confidence.

Winds and seas will generally remain below Small Craft Advisory
thresholds through the period.  The main concerns are a period of
near-shore southwesterly wind gusts of 20 to 25 knots Saturday
afternoon which will result in some choppy seas for mariners. May
also see some brief easterly wind gusts between 20 and 25 knots on
Sunday behind a backdoor cold front. Then winds become ssw Sunday
into Tue as front lifts north as a warm front.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...Air Quality Alert from 11 AM this morning to 11 PM EDT this
     evening for CTZ002>004.
MA...Air Quality Alert from 11 AM this morning to 11 PM EDT this
     evening for MAZ002>005-008>014-017-018-020-021-023-026.
RI...Air Quality Alert from 11 AM this morning to 11 PM EDT this
     evening for RIZ001>008.
MARINE...None.

&&

$$
SYNOPSIS...Nocera/RLG
NEAR TERM...EVT
SHORT TERM...RLG
LONG TERM...Nocera
AVIATION...Nocera/EVT
MARINE...Nocera/RLG/EVT





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