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Area forecast discussion 
National Weather Service Taunton Massachusetts
422 am EDT Tuesday Jul 29 2014

Synopsis...
mainly dry and less humid weather follows today into Wednesday as a
cold front sweeps off the southeast coast early this morning. A few
showers and perhaps a thunderstorm are possible Thursday and Friday...but
most of the time will feature dry weather. A period of steady rain
is possible sometime this weekend if low pressure tracks close
enough to the coast...but confidence is low.

&&

Near term /until 6 PM this evening/...
***beautiful weather today with pleasant temperatures and low humidity***

Surface cold front will be moving offshore by daybreak.
Otherwise...anomalous upper level trough over the eastern U.S. Will
result in cooler than normal temperatures along with low humidity today.
Under a mixture of clouds and sunshine...high temperatures will mainly be
in the middle to upper 70s.

&&

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

A dry airmass in place for late July will combine with mainly clear
skies/light winds...resulting in an excellent night of radiational
cooling. Low temperatures will mainly be in the 50s...to the lower 60s in
the urban heat islands of Boston/Providence. We may even see a few
upper 40s across the normally coolest outlying locations of
southwest New Hampshire/western MA! Some patchy ground fog may develop late in
the typically prone locations...but nothing widespread is
anticipated.

Wednesday...

Upper level trough will remain anchored across the northeast. This
will result in another day with below normal temperatures. Highs should
mainly be in the 70s to near 80 with low humidity. A mixture of
clouds and sun anticipated as a moisture starved shortwave moves
across the region. Mainly dry weather expected...but the shortwave
could result in a passing sprinkle or two. We will have to watch a
weak wave of low pressure passing east of the benchmark...but at
this time appears it should be far enough away to spare even the
cape/islands any measurable rainfall.

&&

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

* a few showers possible on Thursday otherwise quiet weather
* low pressure could bring rain especially to the South Coast Sat

Models are in fairly good agreement through the long term. There
are detail differences of course but overall the synoptic scale
pattern is well modeled. The high amplitude upper level trough
across the eastern U.S. Is the dominant feature through the first
part of the long term. The trough is far enough east that moisture
is somewhat limited across southern New England. There is potential
for a few showers on Thursday with a shortwave rotating around the
trough. Otherwise...expect mainly quiet and seasonable weather
through the end of the work week.

The trough axis starts to shift more to the west this weekend...
allowing moisture to move into the region. A front will approach
the region from the southeast and a wave of low pressure will move
along the front. This will bring steady rain to at least a portion
of the region. There are some discrepancies in the models as to how
close this front gets to southern New England. The closer the front
comes to the area...the more widespread the rain. Model blend
currently brings the precipitation into southeastern Massachusetts and
Rhode Island.

&&

Aviation /09z Tuesday through Saturday/...
forecaster confidence levels...

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

Short term...today through Wednesday...

Today...high confidence. Marginal MVFR ceilings across portions of our
northern and western zones should improve to VFR by daybreak.
Otherwise...VFR conditions along with afternoon sea breezes across
portions of the immediate coast.

Tonight and Wednesday...high confidence. VFR conditions other than
late night/early morning patchy ground fog in the typically prone
locations. Afternoon sea breezes once again expected across
portions of the immediate coast.

Kbos taf...high confidence in taf. Expect an east to southeast sea
breeze to develop during the afternoon.

Kbdl taf...high confidence in taf.

Outlook...Wednesday night through Saturday...

Wednesday night through Friday...high confidence. Mainly VFR. Low
probability of a brief period of MVFR conditions in -shra.

Saturday...moderate confidence. VFR northwest. MVFR conditions more
probable southeast in -shra.

&&

Marine...
forecaster confidence levels...

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

Short term...today through Wednesday...

Today...high confidence. Left over swell will allow Small Craft Advisory seas to
linger into the afternoon across our southern Atlantic waters and
western sounds. Otherwise...winds/seas should remain below Small Craft Advisory
levels across the rest of the region.

Tonight and Wednesday...high confidence. Any left over marginal Small Craft Advisory
seas across the southern Atlantic waters will diminish this evening.
Otherwise...fine boating weather as weak pressure gradient will keep
winds/seas below Small Craft Advisory thresholds along with good visibilities.

Outlook...Wednesday night through Saturday...

Wednesday night through Friday...high confidence. Quiet boating
weather expected with high pressure over the waters.

Saturday...low confidence. More unsettled weather possible with an
approaching front.

&&

Box watches/warnings/advisories...
CT...none.
Massachusetts...none.
New Hampshire...none.
Rhode Island...none.
Marine...Small Craft Advisory for hazardous seas until 2 PM EDT this
afternoon for anz235-237.
Small Craft Advisory for hazardous seas until 8 PM EDT this
evening for anz250-254>256.

&&

$$
Synopsis...Frank
near term...Frank
short term...Frank
long term...rlg
aviation...Frank/rlg
marine...Frank/rlg

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