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Area forecast discussion 
National Weather Service Taunton Massachusetts
1045 am EDT sun Oct 4 2015

a gusty but diminishing northeast flow will continue this
afternoon and tonight. Hurricane Joaquin will track several
hundred miles offshore Monday and Monday night. High pressure will
bring dry and near seasonable conditions Tuesday through Thursday.
Low pressure and an associated cold front will bring scattered
showers late Friday into next weekend.


Near term /until 6 PM this evening/...

Cloud streets are moving off the Gulf of Maine across eastern
mass and Rhode Island. These should spread into central mass and
northeast CT early afternoon. Meanwhile altocu covers much of
western mass and northwest CT with slow trend of suppressing

Strong inversion at 850-900 mb with marine air beneath. The
marine airmass is near saturation in eastern mass but less so in
western New England. Expect the clouds to fill in some more over
Rhode Island/eastern mass with at least some lingering cloud cover in the
west. Look for a partly to mostly cloudy afternoon. Widely
scattered sprinkles possible from the marine clouds in southeast
mass but mainly trace-level precipitation.

High pressure over Quebec and the Maritimes will continue to bring
a northeast flow into southern New England. This is feeding the
cloud streets into our area. Winds should be less than what we
experienced Saturday but with gusts 20-30 miles per hour in eastern mass and
Rhode Island.

For the update...we have bumped maximum temperatures up a couple of degrees
based on observed late morning temperatures. Generally 50s and around 60.


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

Surface high pressure will continue across northern New England
while 700 mb low moves offshore. This will help enhance easterly
flow overnight to saturate the low levels. Therefore believe that
the potential for drizzle and perhaps some fog will develop along
the mass East Coast. However appears that dry air will move across
the interior which may allow clear skies enough for radiational
cooling to occur. Best spot for potential frost/freeze headlines
will be across Franklin County. Held off as there is uncertainty on
the cloud cover potential.

Northeast flow will continue on Monday which will keep the cloud
cover around especially across the coast. Less confident on the drizzle but
still kept it in the forecast. Weak warm air advection will move in which will
increase 850 mb temperatures close to 6-8c. This could result in
temperatures int the low to middle 60s. This will feel quite balmy
compared to the past few days.


Long term /Monday night through Saturday/...

* dry and near seasonable conditions expected Tuesday through Thursday
* scattered showers possible Friday into early Saturday

split flow pattern next week with low amplitude northern stream
across the northern Continental U.S. Which amplifies across the Great Lakes late
in the week as upper ridge builds across the West Coast. One weak
shortwave passes to the north around midweek which brings a cold front
through the region. Then more amplified shortwave energy and associated
frontal system move into new eng Friday into Sat which will bring a
period of showers...otherwise most of the extended period will be
dry. Temperatures moderate at or above seasonable levels Tuesday/Wednesday then cooling a bit
Thursday behind a cold front.


Monday night...
Hurricane Joaquin makes its closest approach to southern New England several hundred
miles offshore. With high pressure to the north...continued NE flow and low
level moisture may keep threat of low clouds and patchy drizzle Monday
night along the southeast new eng coast...otherwise partial clearing
developing from west to east.

Tuesday through Thursday...
high pressure in control for much of the period will lead to mosunny
skies. Seasonable temperatures Tuesday...warming a bit above normal Wednesday in
prefrontal airmass with some locations exceeding 70 degrees. Cold
frontal passage late Wednesday/Wednesday evening will likely be dry given limited moisture
and convergence...then strong high pressure builds to the north Thursday
leading to cooler temperatures.

Friday into Saturday...
next shortwave approaches with GFS/European model (ecmwf) consistent on surface low track
to the north but differ on timing of showers and how quickly this system
moves through. Expect a period of showers sometime late Friday into Sat
but timing very much uncertain. GFS has much of the showers late Friday
into Friday night with drying on Sat...while European model (ecmwf) has the showers late
Friday night into Sat. UKMET and ggem more in line with the slower
European model (ecmwf) so Friday may end up dry while Sat is wet.


Aviation /15z Sunday through Thursday/...
forecaster confidence levels...

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

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

Gusty northeast winds will continue across the region with the
coast seeing close to 25kts. These winds will diminish through the
day and into tonight. Northeast flow will continue into Monday
with gusts near 15kts.

VFR ceilings in the west...but cloud streets moving onshore from the
Gulf of Maine are carrying ceilings around 2500 feet. Expect these to
continue through the afternoon in eastern mass. Ceilings may lift a
little as they move over the warmer land...and may be around or a
little above 3000 feet over Rhode Island which would be borderline VFR.

Widely scattered sprinkles possible in the onshore flow...but no
significant visibilities concerns in any precipitation.

MVFR ceilings expected to expand northward late today into tonight and
possibly reach bdl-bed with VFR persisting to the north. Improving to
VFR Monday...but MVFR lingering in the coastal plain along and east
of bos-pvd. Patchy drizzle possible at times across southeast new eng.

Kbos terminal...moderate confidence regarding potential for MVFR

Kbdl terminal...moderate confidence regarding potential for MVFR

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

Monday night...areas of MVFR ceilings and patchy drizzle
cape/islands and possibly southeast Massachusetts...otherwise VFR.

Tuesday through Thursday...VFR.


forecaster confidence levels...

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

Short term /through Monday/...high confidence.

Have converted most gales to Small Craft Advisory...however lingered gales across the
southern outer waters. NE winds will begin to slack off through out
the day and through Monday. However seas will be slow to subside as
NE swell will continue to move through the waters. May need to
convert Small Craft Advisory to hazardous seas for tomorrow.

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

Monday night into Tuesday...leftover Small Craft Advisory gusts to 25 knots across southern
outer waters in the evening...otherwise winds diminishing and
becoming light on Tuesday. Easterly swell combined with leftover wind
wave will result in seas up to 9 feet outer waters Monday night which
will slowly subside during Tuesday. Small Craft Advisory will be needed through Tuesday and
into Tuesday night for seas.

Wednesday into Thursday...light northwest winds Wednesday...then briefly increasing Post-
frontal north winds late Wednesday night into Thursday morning but likely remaining
below Small Craft Advisory. Winds diminishing late Thursday/Thursday night as high pressure builds
over the waters. Leftover 5 feet seas VFR east waters early Wednesday...then


Box watches/warnings/advisories...
Rhode Island...none.
Marine...Small Craft Advisory until 9 am EDT Monday for anz231>234.
Small Craft Advisory until 8 PM EDT this evening for anz230-
Small Craft Advisory until 9 PM EDT Monday for anz235-237-250-


near term...wtb
short term...dunten
long term...kjc

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