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Area forecast discussion 
National Weather Service Taunton Massachusetts
1023 am EDT Friday Oct 24 2014

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/...
1015 am update...
vertically stacked low south of Nova Scotia with one last
shortwave exiting the region to the south. However...warm
conveyor belt in the comma head continues to rotate a few showers
south across new eng. Activity is light and is diminishing in
coverage. Expect a mainly dry afternoon with just a low probability of
an isolated shower eastern half new eng. Clouds will be slow to erode
with clearing likely waiting until after dark...although some
breaks should develop in western new eng late in the day. With
abundant cloud cover...maximum temperatures will remain mostly in the 50s.
Current forecast on track...made a few modifications to T/TD/pop
grids to reflect current trends.


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

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.


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.


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
slightly above normal by Tuesday.

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 may not be as strong as
mesoscale components would suggest...but something Worth

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 /14z 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.

it will take some time...but expect a gradual improvement with the
mainly MVFR /IFR cape and islands/ conditions improving slowly
with time both due to lifting ceilings and breaking clouds.
Some light rain this morning should dissipate by this afternoon.
Winds mainly northwest...with a few gusts 20+ knots possible at east coastal
terminals through the morning...dissipating this afternoon and

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

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.


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 south of Nova Scotia still producing gusts to
25-30 knots over eastern waters...but these winds will diminish below
25 knots this afternoon. 8-10 feet seas eastern waters will slowly
subside through the afternoon. Small craft advisories have been
dropped for waters west of the Cape Cod canal but continue to the

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...
New Hampshire...none.
Rhode Island...none.
Marine...Small Craft Advisory until 8 PM EDT this evening for anz231-
Small Craft Advisory until 6 am EDT Saturday for anz254-255.
Small Craft Advisory until noon EDT today for anz256.


near term...kjc
short term...nocera
long term...doody

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