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Area forecast discussion 
National Weather Service Taunton Massachusetts
1008 am EDT sun Aug 2 2015

Synopsis...
seasonably warm and dry weather will be featured today across the
entire region. The threat of showers and thunderstorms returns Monday
evening into Tuesday. Pattern change by middle week will result in
temperatures trending a bit below normal late in the week and into
next weekend.

&&

Near term /until 6 PM this evening/...
10 am update...made a few minor updates to temperatures...dewpoints...
and sky cover. But overall the forecast is on track.

Previous discussion...

A very nice Summer day with comfortable levels of humidity and
temperatures in the 80s.

Behind the departing short wave trough heights begin to rise across
southern New England resulting in deep layer subsidence and column
drying from the top down. This will provide the region with dry
weather and lots of sunshine mixed with some hi based scattered
cu/scu.

Light west-northwest winds this morning will become SW this afternoon.

Beach forecast...

Leftover southerly swells of 3 to 4 feet may result in modest surf and
rip currents this morning across south facing ocean beaches of Rhode Island
and Massachusetts. However this afternoon as swells erode surf heights should
lower as well along with a lower risk of strong rip currents.

&&

Short term /6 PM this evening through 6 PM Monday/...
tonight...

Short wave ridging will provide most of the area with dry weather.
However as south-southwest flow becomes established the NAM and nmm suggest low
level moisture on the increase with stratus and fog overspreading the
South Coast of Massachusetts and Rhode Island. This may result in spotty light drizzle
across this region.

South-southwest flow will also yield increasing dew points which in turn will
result in warmer conditions than previous nights.

Monday...

Anomalous closed low over Ontario with short wave trough rotating
through the eastern Great Lakes into western New York state late in the day.
Given these features are well west of New England very little in the
way of height falls or cooling temperatures aloft occurs over our region.
Thus much of the area may remain dry most if not all of the daylight
hours. The exception may be across western Massachusetts where deep layer
moisture and forcing for ascent increase somewhat by late in the
day. This will yield a low risk for T-storms toward sunset. Also
low risk for a few strong storms in western Massachusetts/CT as deep layer
shear increases along with steepening middle level lapse rates.

Other area of precipitation will be in the morning over the South Coast of
Massachusetts and Rhode Island where low clouds and drizzle may persist into the morning
before improving toward midday.

Otherwise looks to be a very summery day with warm and muggy
conditions ahead of the approaching cold front with highs 85 to 90
away from the South Coast /cooler there given south-southwest surface winds off
the ocean/ along with dew points creeping upward to 65 to 70. However
an increasing south-southwest breeze will help take the edge off the very warm
and muggy conditions.

&&

Long term /Monday night through Saturday/...
highlights...

* showers and thunderstorms Monday into Tuesday
* pattern change by middle week bringing below average temperatures
* unsettled weather for the end of the week

Overview...

00z guidance is in good agreement for this portion of the
forecast. Upper-level trough centered near James Bay will begin
to migrate eastward...keeping southern New England within a broad trough with
southwest flow. Several shortwaves moving through the flow will
bring showers and thunderstorms for the first half of the week. A
cooler pattern will be in store by middle-week as low progresses
eastward towards the Maritimes. By the end of the forecast
period... upper level trough begins to sharpen over the region.
Still a lot of timing issues especially within each shortwave...but for
now appears precipitation will be near the area Thursday and again
Sat/sun.

Dailies...

Monday night into Tuesday...increasing confidence.

Cold front will slowly March across the region Monday night and
stall on Tuesday. Guidance still indicates that there will be enough
instability as well as decent middle-level lapse rates to maintain
thunderstorms overnight across the area. Shear values also
increase to 40-50 kts and with k values above 30c...cant rule out
a strong to severe thunderstorm across the region overnight.

A more potent shortwave will move through the flow on Tuesday.
Pushing the cold front across the rest of the region. Still timing
issues amongst the guidance but cant rule out thunderstorms on
Tuesday...especially across eastern half of the region. Still plenty of
shear /40-50 kts/ with decent middle-level lapse rates and cape
values above 1500 j/kg...indicating the potential for
thunderstorms...some of them strong.

This system is still 2 to 3 days away but does need to be watched.
The cips analogs indicate that this pattern has developed strong
to severe storms. In fact Storm Prediction Center has put the area in a marginal risk
for this time period. If everything lines up gusty winds and hail
could be the main threats from these storms. Stay tuned to latest
forecasts for updates on the severe weather potential.

Wednesday into Thursday...moderate confidence.

Elongated trough will be the general flow over the region. High
pressure will build out to the west leading to a dry Wednesday.
Potent shortwave will develop a southern stream low on Thursday
over the middle-Atlantic and move south of southern New England. Depending on the
track...could see widespread rain late Thursday into Friday
morning. There are still issues with the track but highest
confidence in precipitation is across the South Coast.

Overall temperatures will be below average with high temperatures in the low
80s to middle 70s. Low temperatures low 60s to the middle 50s.

Friday and beyond...moderate confidence.

Break in the precipitation on Friday as subsidence takes hold of the
region. Another potent shortwave will approach the region late
Friday into Saturday. The operational guidance indicates some sort
of rainfall across the region as a more significant coastal low
pressure tracks northeast...much like a winter Nor'easter. This is
still 6-7 days out so only kept a chance precipitation for now.

&&

Aviation /14z Sunday through Thursday/...
forecaster confidence levels...

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



Today...VFR with dry weather and good visibility. Light west winds this
morning becoming SW this afternoon. Low risk of seabreeze eastern
Massachusetts. High forecast confidence.

Tonight...VFR and dry weather for most of the region. Area of
concern is South Coast of Rhode Island and Massachusetts where IFR in low ceilings/fog and
drizzle is possible. High confidence inland...lower confidence
along the South Coast.

Monday...IFR possible South Coast of Massachusetts and Rhode Island in patchy fog and
drizzle. Improving as the day progresses. VFR elsewhere with low
risk of T-storms western Massachusetts and CT late in the day. Moderate
confidence.

Kbos terminal...high confidence in taf. Low risk of seabreeze this
afternoon.

Kbdl terminal...high confidence in taf.

Outlook /Monday night through Thursday/...

Monday night into Tuesday...moderate confidence. VFR much of the
time. MVFR/IFR within any scattered showers and thunderstorms
through the period. A low risk for a strong storm is possible.

Wednesday...moderate confidence. VFR.

Thursday...moderate confidence. Mainly VFR with MVFR increasing
late in the day across the South Coast in approaching rain showers.

&&

Marine...
forecaster confidence levels...

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

Short-term /through Monday/...moderate confidence.

Today...3 to 4 feet southerly swells slowly erode today. West-northwest winds
become SW this afternoon. Good visibility and dry weather.

Tonight...south-southwest winds persist. Low clouds/fog and drizzle may impact
the south coastal waters second half of the night.

Monday...south-southwest winds increase to 15 to 20 knots with gusts up to 25 knots
possible. Low clouds/fog and drizzle may impact the southern waters
in the morning with improvement during the afternoon.

Outlook /Monday night through Thursday/...moderate confidence.

Monday night into Tuesday...approaching cold front will increase the
risk for showers and thunderstorms over the waters. SW winds will
increase ahead of the front building seas up to 5-7 feet. Winds
could be gusty requiring Small Craft Advisory.

Wednesday...seas will slowly relax however westerly winds will still
be gusty. Could still need Small Craft Advisory for the waters.

Thursday...seas and winds will relax below Small Craft Advisory.

&&

Box watches/warnings/advisories...
CT...none.
Massachusetts...none.
Rhode Island...none.
Marine...none.

&&

$$
Synopsis...nocera/dunten
near term...nocera/dunten/rlg
short term...nocera
long term...dunten
aviation...nocera/dunten
marine...nocera/dunten

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