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Area forecast discussion 
National Weather Service Taunton Massachusetts
426 PM EDT sun Mar 29 2015

dry weather through tonight then a cold front sweeps down from
Canada and crosses New England Monday. A fast-moving area of low
pressure passes south of New England Tuesday night...potentially
bringing more light rain and/or snow showers. A more significant
storm may approach late this week.


Near term /until 6 am Monday morning/...
215 PM update...high pressure centered over the Middle-Atlantic
States has brought sunny skies and dry weather to southern New
England. Temperatures are slowly climbing into the middle to upper
30s. Should see a few locations hit 40 by the end of the day.

Tonight...cold front and upper trough moving through the Great
Lakes will push an upper level ridge through southern New England
overnight. Mostly quiet overnight...with clouds building in from
the west late tonight towards Monday morning. Temperatures should
be a few degrees warmer than last night but will remain in the 20s
for most locations.


Short term /6 am Monday morning through Monday night/...
a cold front and upper trough swing across New England on Monday.
Expect showers along/ahead of the front. Support for showers
should start near sunrise in the west and middle to late morning in
the east. The cold frontal passage should be midday/early
afternoon west and middle to late afternoon east.

Temperature profiles allow for snow initially across the
northwestern zones but expect warming during the morning that will
change this to rain. Any snow accumulations should be limited to
an inch or less.

Cold advection mixing behind the front May Draw upon 35 knot winds
aloft bringing them to the surface in middle to late afternoon gusts.
We will trend forecast gusts higher with this package but stay a
little below this full potential...roughly 25 to 30 knots.

Monday night...cold advection continues with excellent mixing in
place. Expect gusty westerly winds to continue through the night
so have increased winds and wind gusts. Overnight lows will be in
the 20s to low 30s.


Long term /Tuesday through Sunday/...

* Alberta clipper passes by to our south Tuesday night
* moderating...Spring-like temperatures late this week
* increasing chances for precipitation sometime during Easter


Northwest flow to start over the region Tuesday...lasting into
next weekend. Several shortwaves will be moving through this
flow...allowing for the active pattern to continue. 29/12z model
guidance is in good overall agreement...with some discrepancies
with a clipper-like system Tuesday into Wednesday...and with a
more significant low pressure late this week. Will continue to a
favor a consensus approach until these details of these systems
come into better focus.


* Tuesday...high confidence.

Tuesday will be mostly dry as southern New England is squeezed
between two systems. Winds will continue to gust through the day.
Temperatures will be in the middle to upper 40s but with the will feel like the upper 30s. Clouds will be on the
increase throughout the day as the next system approaches.

* Tuesday night...moderate confidence.

Next shortwave will quickly dive through the flow from Canada and
move just south of southern New England. The majority 29/12z
guidance continues to keep this storm well to our south...with
almost no impact at all on our weather. The CMC is the slowest and
farthest north with this system. That said...will trend this
portion of the forecast drier than previous forecasts...with
minimal impact on southern New England.

Since the passage of this storm will be at night...that raises the
possibility for more snowfall if temperatures lower fast enough.
Will need to continue to watch the trends with this system since
it could produce a quick 1-2 inches of snow across portions of
southern New England should the track be farther north.

* Wednesday into Thursday...moderate confidence.

A weak ridge will build behind a clipper system Wednesday into Wednesday
night. This will allow for a strong high pressure to build over
southern New England. Latest trends in the guidance is for most
of the day Thursday to remain dry as high pressure slowly breaks

* Thursday night into Saturday...low confidence in timing. Moderate
confidence in precipitation occurring.

High pressure will move offshore as a low pressure system moves
across southern Canada. This system will drag a cold front across
the area either Thursday night or Friday. It appears there could
be a few waves which develop along this decided to not
try to time precipitation to specifically. Temperatures Friday
should be above average. Temperatures will turn colder behind a
frontal passage by Saturday or Sunday.

* Sunday...moderate confidence.

A weak trough lingers across New England. The question will be
the amount of moisture it has to work with. Kept this portion of
the forecast dry...for now.


Aviation /20z Sunday through Friday/...
forecaster confidence levels...

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

Short term...high confidence through Monday night

Through 00z...VFR. Sea breeze at Boston.

Tonight...VFR. Increasing clouds after midnight but above 3000

Monday...VFR. Brief MVFR possible in scattered snow showers early
then scattered rain showers. Cold front moves through from west to
east during midday to mid-afternoon. Gusty west winds behind the
front may reach 25-30 knots.

Monday night...VFR. Gusty west winds behind the front may reach
25-30 knots.

Kbos taf...high confidence.

Kbdl taf...high confidence.

Outlook...Tuesday through Friday...high confidence.

Tuesday...VFR. Gusty west wind between 20-30 kts.

Tuesday night...VFR for most of the period. May see MVFR south of
Mass Pike in rain/snow showers.

Wednesday into Thursday...VFR.

Friday...mainly VFR. Scattered MVFR in showers.


forecaster confidence levels...

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

Short term...tonight through Sunday night...

High confidence.

Small craft advisories have been issued for all waters for a
combination of winds and seas. Seas will diminish briefly this
evening...then southwesterly to westerly winds and seas will pick
up in advance of a cold front late tonight or early Monday
morning. Winds will begin to diminish Monday evening but may
remain gusty through Monday night. Rain showers are possible ahead
of the cold front.

Outlook...Tuesday through Friday...moderate confidence.

Tuesday...high pressure will be over the area...however winds
will remain gusty...reaching near 30 knots. This will keep seas
above Small Craft Advisory thresholds.

Tuesday night...quick-moving system will move over southern
waters. This will keep both seas and winds above Small Craft
Advisory thresholds.

Wednesday into Thursday...high pressure will arrive...allowing
for seas and winds to relax.

Friday...another cold front approaches the waters...resulting in
increasing southwest winds and seas.


Box watches/warnings/advisories...
Rhode Island...none.
Marine...Small Craft Advisory from 6 am to 7 PM EDT Monday for
Small Craft Advisory from 6 am to 2 PM EDT Monday for anz230-
Small Craft Advisory from 6 am Monday to 9 am EDT Tuesday for
Small Craft Advisory until 9 am EDT Tuesday for anz250-254-255.
Small Craft Advisory from 6 am to 5 PM EDT Monday for anz251.


near term...rlg
short term...rlg
long term...Belk

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