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Area forecast discussion 
National Weather Service Taunton Massachusetts
1012 PM EDT sun Oct 4 2015

high pressure over eastern Canada will bring dry weather and a
cool northeast flow to southern New England. Hurricane Joaquin
will track several hundred miles offshore Monday and Monday night.
High pressure will prevail Tuesday through Thursday with dry and
near seasonable conditions. Low pressure and an associated cold
front will bring scattered showers late Friday into Saturday.
Another high approaches with more dry weather late next weekend.


Near term /until 6 am Monday morning/...

1030 PM update...

Trend in the forecast remains on track for this evening. Low
clouds continue to move into the region from the east. Could see
some spotty drizzle out of any of the low clouds. Otherwise
temperatures will hold into the 50s overnight across southeast mass
while in the northwest could drop into the low 40s to upper 30s. Still
have some uncertainty with the frost advection as the clouds are trying
to move into the interior plus the dewpoint is only at 38f. Will
continue to monitor trends.

Previous discussion...
tonight...high pressure will be centered over Maine and the
Maritimes. This will maintain a northeast flow into southern New
England. The ridge axis looks like it will move over western mass
overnight which would bring light winds to that part of our area.
One question is whether skies in northwest mass will remain mostly
clear which would allow radiational cooling. With afternoon dew
points around 36 degrees this would bring concern for patchy frost
in the western parts of Franklin and Hampshire counties late at
night. A frost advisory has been issued for these locations for
late tonight. Farther south and east...clouds and residual wind
should keep temperatures cool but not frosty.


Short term /6 am Monday morning through Monday night/...
high pressure remains in control with northeast winds and low
clouds remaining over southeast New England while the interior has
light wind and partly cloudy skies. Hurricane Joaquin makes its
closest approach to New England Monday evening...with the center
about 510 miles southeast of Nantucket. Joaquin may contribute to
the clouds over southeast New England but should be too far
offshore to generate significant effects for our area.

Temperatures in the mixed layer...up to 925 mb and possibly 900 mb...over
the CT valley would support maximum surface temperatures in the middle 60s. Clouds
farther east should keep temperatures a little the upper 50s
to around 60. Dew points in the upper 30s and 40s suggest min
temperatures in that range Monday night.


Long term /Tuesday through Sunday/...

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


Medium range models and ensembles continue to feature split flow
pattern across the lower 48...with a general flat progressive
upper flow across the northern tier states through middle week. Weak
short wave moves along in this flow...passing across northern New
England during Wednesday with associated dry cold front. Stronger short
wave in across the western Great Lakes looks to link up with
weakening short wave over western Texas around Thursday in response to a
500 mb ridge building across The Rockies. Model solution variance
increases with this feature as it moves east Fri/ timing and
track issues come into play. Continued with trend from previous
forecast and kept chance of showers going for Friday into early Sat.
Trend is for a return to dry and slightly cooler conditions late
next weekend.


Tuesday through Thursday...
will continue to see high pressure for the most part during this
timeframe. Mostly sunny conditions expected with seasonal temperatures
for Tuesday. Temperatures will rise up to 5 degrees above normal on Wednesday
ahead of approaching dry cold front with some locations reaching
up to about 70 degrees. Once the front pushes through with little
more than a wind shift on Thursday...mostly sunny conditions return
though temperatures will only reach the middle 50s to middle 60s as large high
pressure arrives from western Quebec.

Friday through Sunday...
models remain consistent in bringing short wave across from the
central u... some question on translation on timing and track
of surface system. GFS appears to be the faster of the two major
models...moving it across rather quickly Sat morning. However...
the European model (ecmwf) remains slower in exiting the front and has more
moisture associated with it into well as trying to
form weak low pressure on the front S of New England into Sat night.
For now...have chance probability of precipitation going for mainly Friday afternoon into
early Sat...and kept slight chance probability of precipitation for most of Sat. 12z ggem
was much slower than either the GFS or European model (ecmwf) so was discounted for
this forecast.

Have kept slight chance probability of precipitation going across northwest Massachusetts into Sunday...
otherwise dry conditions out. Looks like high temperatures will be close
to seasonal norms.


Aviation /02z Monday through Friday/...
forecaster confidence levels...

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

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

Tonight through Monday...
lower ceilings expand across Rhode Island/northeast CT and eastern mass with
heights 2000 to 2500 feet...especially south/east of a bed-orh-hfd
line. Northeast winds will linger in this cloud zone with gusts 20
to 25 knots over the cape and islands. MVFR ceilings linger over Rhode Island
and southeast mass on Monday.

Monday night...
lingering clouds as Hurricane Joaquin passes 510 miles southeast
of Nantucket. Mainly VFR.

Kbos terminal...moderate confidence regarding potential for MVFR
ceilings tonight.

Kbdl terminal...moderate confidence regarding potential for MVFR
ceilings tonight.

Outlook /Tuesday through Friday/...

Tuesday...high confidence. Mainly VFR. May see patchy late
night/early morning fog with local MVFR conditions in the
normally prone inland locations... and possibly reaching to S
coastal Massachusetts and Cape Cod.

Wednesday...high confidence. Leftover patchy MVFR visibilities in fog
through middle morning...otherwise VFR.

Thursday-Friday...moderate confidence. VFR during Thursday...then
lowering to patchy MVFR-IFR in scattered showers Thursday night-Fri. May see
local MVFR-IFR ceilings/visibilities in patchy fog late Thursday night into Friday
morning mainly across normally prone inland valleys.


forecaster confidence levels...

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

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

Northeast winds of 25 knots on all waters through early tonight
will diminish on some of the waters but linger on the southern
outer waters tonight and Monday. Any remaining 25 knot winds will
diminish Monday night as distant Hurricane Joaquin moves off to
the east.

The persistent northeast wind will keep seas up through Monday
night with 5 to 9 foot seas on all exposed waters.

Small Craft Advisory will remain in effect for most waters through
this period.

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

Tuesday and Wednesday...N-NE winds early Tuesday will back to northwest
during Tuesday...then diminish Tuesday night/Wed. Winds may shift to west-SW
Wednesday afternoon ahead of approaching weak front. Easterly swells up
to 7-9 feet will continue...highest on the outer waters into Tuesday
night then will slowly subside. Small crafts for seas will likely
continue through Wednesday.

Wednesday night through Friday...winds shift back to northwest Wednesday night
then north on Thursday...gusting up to around 20 knots. Seas may briefly build
to around 5 feet on the outer waters on Thursday. Winds then veer to southeast-S
Thursday night and Friday...with gusts again up to 20 knots on the outer


Box watches/warnings/advisories...
Massachusetts...frost advisory from 4 am to 9 am EDT Monday for maz002-008.
Rhode Island...none.
Marine...Small Craft Advisory until 2 PM EDT Monday for anz232-233.
Small Craft Advisory until 8 PM EDT Monday for anz231-234.
Small Craft Advisory until 8 am EDT Tuesday for anz235-237-250-


near term...wtb/dunten
short term...wtb
long term...evt

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