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Area forecast discussion 
National Weather Service Taunton Massachusetts
250 am EDT Tuesday Jul 26 2016

Synopsis...
high pressure will bring dry but continued hot conditions today
and Wednesday. A cold front approaches the area on Thursday. This
front may linger in our area into this weekend.

&&

Near term /today/...

Upper shortwave moves across New England overnight, driving a
surface wind shift across our area. Even with that wind shift,
airmass temperatures cool very little. High pressure builds in
from the west bringing subsidence and sunshine and deep mixing.
But lingering moisture near 850 mb should allow for some diurnal
clouds to develop.

Mixing will bring down some wind gusts near 20 knots. Temps
aloft are roughly 15-17c on the GFS and 16-18c on the European model (ecmwf).
Mixing should allow for Max surface temps in the upper 80s to mid
90s. Dew points over upstate New York are in the mid 60s, with
low 60s to the north and west. This will mean a little less
humidity, but still enough to be noticed.

&&

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

Tonight... high presure builds in with diminishing wind. Dew
points 60 to 65 will keep min temps in the 60s, with low 70s along
the coast.

Wednesday... high pressure remains in control with sunshine. Upper
flow shows a weak shortwave moving through, but less cloud-level
moisture for sky cover. Light wind near the surface will allow for
developing sea breezes along the coasts. Temps aloft around 18c
should support sfc Max temps in the interior in the low to mid
90s, cooler values near the coastline. Dew points linger around
60 or in the lower 60s.

&&

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

* cold front approaches the region on Thursday
* showers and thunderstorms are possible again Friday and possibly
into the weekend

Overview...

25/12z guidance is in decent overall agreement through mid
week.However there continues to be significant differences in
solutions for Thursday night and on. 12z models seem to be in
general agreement on bringing a cold front into our area Thursday or
Thursday night. However, models differ on when the front pushes
south of our area. Will continue to go with a consensus approach
for this forecast.

Details...

Thursday...we should see another day of hot conditions, however a
cold front will be approaching our area from the N/NW. Moisture
increasing along the front should enable isolated to scattered
afteroon T-storms on Thursday/Thursday evening.

Thursday night and Friday...uncertainty increases with this portion
of the forecast. Models differ on how far south cold front pushes,
as well as timing on potential open wave or deeper low pressure
passing near/south of our area. Will have chance pops for showers/T-
storms. Friday high temps expected to be a few degrees lower than
previous days.

Saturday and Sunday...lots of uncertainty remains with this portion
of the forecast, leading to a low confidence forecast. European model (ecmwf) keeps
frontal boundary nearby, with potential low pressure moving along
the front. GFS pushes the front south of our area for much of the
weekend. Will continue with a chance of showers for this timeframe.

Monday...continued significant amount of uncertainty for this
timeframe, could have a drier period with frontal boundary exiting
the area. Will go with only slight chance pop for this period.

&&

Aviation /06z Tuesday through Saturday/...
forecaster confidence levels.

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

Short term /through Wednesday/... high confidence.

Today... VFR for the most part. Areas of IFR cigs/vsbys in
morning fog/low clouds will quickly burn off. Northwest winds with
gusts 15-20 knots during the afternoon.

Tonight... VFR. Patches of IFR cigs/vsbys in fog late at night.

Wednesday... VFR. Fog Burns off around sunrise. Light variable
wind becoming onshore along the coastline.

Kbos taf...high confidence in taf.

Kbdl taf...high confidence in taf.

Outlook /Wednesday night through Saturday/...moderate to high
confidence.

Moderate confidence Thursday through Saturday.

Mainly VFR conditions Thursday, except MVFR cigs/vsbys possible
in scattered afternoon/eveningshowers/thunderstorms.

Friday through Saturday...mainly VFR, except MVFR cigs/vsbys
possible in periodic showers and thunderstorms. Potential for
patchy low ceilings/fog at night.

&&

Marine...
forecaster confidence levels.

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

Short term /through Wednesday/...high confidence.

Winds remain below 20 knots and seas below 5 feet through the
period. Winds become northwest today, then variable tonight and
Wednesday.

Outlook /Wednesday night through Saturday/...moderate to high confidence.

During Thursday into Saturday winds and seas are expected to
remain below Small Craft Advisory criteria, but the potential exists for areas of
low clouds, fog, and scattered showers and thunderstorms which
would limit visibilities at times.

&&

Fire weather...

Much drier conditions are expected today across southern New
England behind the departing cool front. Minimum relative humidity
is expected to range from 30 to 40 percent across much of the
area. The exception is along Cape Ann and the cape/islands, where
minimum relative humidity values of 40 to 60 percent are forecast. Northwest
winds around 10 mph may gust to 20 mph at times.

Winds are expected to be lighter on Wednesday with nearshore sea
breeze develompent. However, minimum relative humidity will again reach 30 to 40
percent across the interior. Along east coastal Massachusetts and southern
RI, sea breezes will allow for higher minimum relative humidity of 40 to 70
percent.

&&

Box watches/warnings/advisories...
CT...none.
Massachusetts...none.
Rhode Island...none.
Marine...none.

&&

$$
Synopsis...wtb/nmb
near term...wtb
short term...wtb
long term...nmb
aviation...wtb/nmb
marine...wtb/nmb
fire weather...

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