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Area forecast discussion 
National Weather Service Taunton Massachusetts
408 am EDT Friday Oct 24 2014

Synopsis...
the early season coastal storm that brought strong winds and
heavy rains to the region Thursday will continue to move slowly out to
sea today. Scattered light rain showers this morning will dry up
and give way to just cloudy skies this afternoon. A weak ridge of
high pressure provides dry and seasonably mild weather
Saturday.Behind the front...dry but blustery weather follows for
Sunday with warming early next week. A cold front may bring more
rain late Wednesday into Thursday.

&&

Near term /until 6 PM this evening/...
latest water vapor imagery indicates vertically stacked occluded low
east of New England over Georges Bank. Its comma-head/trowal rains
stretch from the Canadian Maritimes extending southwest into
Maine/NH/MA/CT and Rhode Island. This warm/moisture conveyor belt precipitation
/albeit light/ will continue to pivot across the region this morning
and slowly move offshore this afternoon. While the afternoon hours
should be mainly dry...comma-head clouds will linger much of the day
with some partial clearing/sunshine possible toward sunset across
western CT/MA.

Cloud cover/scattered showers and north-northwest winds will provide cool
weather today...especially this morning. Not expecting much of a
temperature rise with highs today only about 5-8 degrees away from
current/predawn temperatures.

&&

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

Closed low over Nova Scotia continues to move northeast. This
results in cyclonic flow transitioning to a more zonal flow over
southern New England. This will yield clearing skies. A modest northwest
wind will preclude winds/blyr from decoupling. This will result in a
seasonably cool night.

Saturday...

Appears the better of the two weekend days as weak short wave
ridging moves across the area and provides enough anticyclonic flow
and associated subsidence for mostly sunny conditions. This combined
with west-northwest winds will result in mild conditions with temperatures well into
the 60s...several degrees above normal. The immediate south may see
temperatures drop a bit late in the day as surface winds become southwest
off the ocean.

&&

Long term /Saturday night through Thursday/...
* chance of showers Saturday night into Sunday
* drier weather for Monday and Tuesday with high pressure around
* rainy Wednesday night into Thursday with a cold frontal passage

Overview and model preferences...
both operational and ensemble guidance shows fairly good
agreement through about the middle portion of next week. At which
point there is more divergence due to issues regarding a more
amplified pattern development. Given the building ridge across the
east Continental U.S. And the western Atlantic by that period...the slower solution
/one favored by the European model (ecmwf) and several gefs/ecens members/ will be
given more weight at this time. This also suggests that a frontal
boundary moving through Tuesday night-Wednesday may stall close enough to
southern New England for continued -shra activity...but at this
point...drier northwest flow may dominate so using only some weight will
still likely yield a mainly dry forecast by the end of the week.

As mentioned above...after a robust but fast moving
shortwave/cold front combination slides through Sat night into
sun. There is a transition toward more zonal flow across the
NE...but under building subtropical ridge through the middle of
the week. Aside from the dry weather and subsidence...this also
suggests a warming trend such that temperatures may reach above normal
Tuesday and Wednesday. A second front moves through middle week followed by
some uncertainty in how dry it will be given the location of the
the frontal boundary as it stalls offshore.

Details...

Sat night into sun...
a robust shortwave will be moving across the region with low pressure
sliding through Quebec...dragging a fast moving cold front across
the region during the overnight hours. West flow ahead and northwest flow
behind...within an already dry column suggests that this frontal
passage is mainly dry in spite of of the f-general apparent and acuity
of the upper level wave. Still...will be issuing some slight to
maybe even low end chance probability of precipitation given this lift potential and precipitable waters
about 0.75. Otherwise...fair amount of cloud cover at least
overnight along with some gusty winds with the frontal passage given 35-45
knots winds between h92 and 850 mb. Clouds suggest overnight temperatures in
the middle 40s to middle 50s. Blustery northwest flow on sun with gusts 20-3o
miles per hour at times possible and plenty of cold advection SC suggest
highs below normal...mainly in the 50s.

Monday and Tuesday...
high pressure will be sliding over the region from the SW...a warm
front moving into Ontario and Quebec late Monday night. So expect a
warming trend through the period with temperatures near normal Monday...to
slightly above normal by Tuesday.

Wednesday...
surface cold front will be sliding across the region as low pressure
moves through Quebec. Given the increasing temperatures and dewpoints along
with precipitable waters approaching 1.5 inches...looks to be enough instability
available for widespread -shra but maybe not enough for thunder
at this point. Could be some gusty winds with the frontal passage/showers as
well given h92 winds approaching 45 knots. Still...its entering
territory of a building ridge...so may not be as strong as
mesoscale components would suggest...but something Worth
watching.

Thursday and Friday...
although brief ridging is likely behind the frontal passage.
There are some disagreement as guidance may attempt to develop yet
another cutoff low pressure but this time in/near northern New England. As
mentioned above...there are some differences here which will need
to be resolved...but brief high pressure may give way to yet another
coastal low pressure by the latter half of the week depending on where
the front stalls and the ultimate depth and location of the upper
level cutoff. For now...none to slight chance probability of precipitation yield the
uncertainty along with seasonable temperatures.

&&

Aviation /08z Friday through Tuesday/...
forecaster confidence levels...

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

Short term /through Saturday/...moderate confidence today then
increasing to high confidence tonight and Sat.

Through 12z...

Not much change with IFR over southeast Massachusetts and MVFR elsewhere.
Scattered light rain showers will persist. Modest north winds continue
over eastern Massachusetts.

After 12z...

Slow improvement with showers dissipating and moving offshore.
Also ceilings and visibilities lifting to MVFR and VFR from west to east. North
winds becoming more north-northwest with time.

Tonight...
skies become clear along with VFR visibilities as winds become west-northwest.

Saturday...

VFR along with a modest west wind.

Kbos...moderate confidence in taf today but increasing to high
tonight and Sat.

Kbdl...moderate confidence in taf today but increasing to high
tonight and Sat.

Outlook...Saturday night through Tuesday...

Saturday night through Tuesday...high confidence.
Mainly VFR. Low probability of scattered showers Saturday night.

&&

Marine...
forecaster confidence levels...

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

Short term /through Friday night/...

Today...gale center over Georges Bank during the predawn hours of
Friday is yielding north winds 20 to 30 knots across the southern New England
waters. These winds will slowly slacken and become north-northwest this
afternoon as the gale center tracks toward Nova Scotia. Visibility 2 to 4
miles in areas of fog and showers this morning but improving this
afternoon. Still very rough seas /12-16 feet/ across the eastern Massachusetts
waters in a combination of east-northeast swells and northerly wind waves.

Tonight...gale center near Nova Scotia continues to move northeast
away from New England. This will result in subsiding winds and seas.

Saturday...tranquil conditions as a weak ridge of high pressure moves
across the waters...yielding a modest west wind becoming SW late in
the day. Leftover NE swells across the eastern Massachusetts waters.

Outlook...Saturday through Tuesday...

Saturday night and Sunday...high confidence in at least Small
Craft Advisory conditions. West winds increase ahead of a front which
will cross early Sun morning. The winds shift back to the northwest sun
behind the front with seas building 5-8 feet. Wind gusts around 25
to 30 knots possible. Low chance for gale force gusts Sun night.

Monday...moderate confidence...winds and seas diminish as high
pressure builds over the waters.

Tuesday...moderate confidence...winds and seas below Small Craft Advisory
threshold as high pressure is still over the region.

&&

Box watches/warnings/advisories...
CT...none.
Massachusetts...none.
New Hampshire...none.
Rhode Island...none.
Marine...Small Craft Advisory until 8 PM EDT this evening for
anz231>234-250-251.
Small Craft Advisory until 10 am EDT this morning for anz230-
235-237-256.
Small Craft Advisory until 6 am EDT early this morning for
anz236.
Small Craft Advisory until 6 am EDT Saturday for anz254-255.

&&

$$
Synopsis...nocera/doody
near term...nocera
short term...nocera
long term...doody
aviation...nocera/doody
marine...nocera/doody

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