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Area forecast discussion
National Weather Service Taunton Massachusetts
712 PM EST Wed Feb 22 2017

high pressure centered southeast of New England will bring dry
and unseasonably warm conditions into Thursday night. A cold
front moves into southern New England Thursday night. However
this front pushes northward, away from the area on Friday as a
warm front. A strong cold front will cross the region late
Saturday afternoon and night, bringing areas of rain and patchy
fog. There will be a low chance for isolated thunderstorms as
the front passes. Near seasonable temperatures will return
early next week, with blustery conditions on Sunday and Monday.
There may be another chance for precipitation around the middle
of next week.


Near term /until 6 am Thursday morning/...
4 PM update...
dry weather anticipated overnight with surface high pressure
centered offshore and southeast of our area. A weak shortwave
passing thru overnight could produce a period of mid deck clouds.
Otherwise, light winds out of the SW/S becoming calm or light and
variable for much of the area. This will allow for good radiational
cooling. Continue to expect min temps near dew point, mid 30s to
near 40. Expecting some patchy fog/areas of fog to develop.


Short term /6 am Thursday morning through Thursday night/...

High pressure remains offshore with southwest flow across
southern New England, while low pressure passes well north of our
area, from the northern Great Lakes region into southern Ontario and
Quebec. Continue to favor a dry forecast for southern New England
during Thursday. Our area remains in a SW flow, dry and unseasonably
warm. Any fog should lift/dissipate early, but may see stratocumulus
developing during the day. Hence partly to mostly sunny skies

Southwest jet associated with this system brings 20-25 knot
low level winds to our area Thursday afternoon. Could be a few
gusts in this range during the afternoon especially across Rhode Island
and eastern Massachusetts.

Continuing with previous forecast high temps for Thu, favoring the
high end of model guidance. Noting the record high temps
listed in the climate section, this would suggest values at or
near record high at pvd and orh, while bos and bdl records are
well above this.

Thursday night...

May see patchy drizzle and fog develop Thu night with reduced
visibilities. A light SW wind holds up for part of the
night. However a cold front is expected to sag southward into our
area. Although exact placement of this front not for certain, models
on average showing it extending roughly east-west across Massachusetts for 12z Fri.
There is a slight chance to low chance pop for showers with the
front. High surface dew points south of the front should be 40-45
for much of the area. With a light SW wind south of the front,
areas of fog greater for locales with a leftover snow pack at
that point, as well as south coastal Massachusetts/Rhode Island with SW flow
off the water.


Long term /Friday through Wednesday/...

* front shifts north of the region late Fri/Fri night with
scattered showers
* areas of drizzle and patchy fog Fri night/early Sat
* mild with widespread areas of rain Sat into Sat night
* dry, blustery and cooler sun/Mon


12z models suite continues showing a good overall handle on the
surface and upper level features even in the progressive flow
aloft through the weekend. Timing and track differences with
individual features work in from about Monday Onward, especially
with a possible system that may pass near or S of the region
around the late Monday/Monday night timeframe. Another front may
try to approach around Wednesday, but again with fast flow
across the northern stream, low confidence with the timing and
track of this system.



Cold front looks to stall across the north CT/Rhode Island into southeast mass Fri
morning. This will keep a chance for showers across most of the
region. As 500 mb ridge axis crosses the region, will see winds
aloft shift to SW, which will help push the front back to the north
of the region taking most of the showers with it. Big question
will be whether there may be enough breaks in the clouds mainly
across southern areas Fri afternoon to bring temps up to around
60. Onshore winds will keep temps cooler along the coast. Clouds
and leftover showers will also limit the temp rise generally north
of the Mass Pike.

Most model guidance was stubborn in keeping temps close to 60
across north CT/Rhode Island and southeast interior Massachusetts Fri afternoon, then mainly in
the lower-mid 50s for highs across most of the remainder of the
region. With an onshore flow, readings will hold in the upper
40s across the Outer Cape and Nantucket.

SW flow at the surface and aloft ahead of approaching strong cold
front and 500 mb cutoff low pres will slowly shift east Fri night. Will
see areas of drizzle and patchy fog along with lingering
showers in the moist low level flow.


Cutoff 500 mb low shears north-NE into western Quebec late Saturday,
but remaining strong short wave will shift east Sat night. Surface
front will quickly push east across the region.

Short range models, specifically the 12z NAM, signaling quite a
bit of instability with and ahead of this front, including Lis
near zero, total totals from 50-54, showalter index of -2 to -3
and tq values around 20. Also lapse rates on order of 7c/km or
higher at about 700 mb at both kalb and kbdl Sat evening, and up to
8c/km at kore overnight. However, noting some mixed signals.
BUFKIT soundings showing several saturated soundings until just
before the instability moves in, with the best shot across the east
slopes of the Berkshires as well as the CT valley region.
Strong low level jet will move across as well, with forecasted
speeds on order of 50 kt at 3kft at both kbdl and kbaf and 52 kt
at 2kft at kalb. Again, though, there is capping in place so
will have to see if the cap can be broken. Will be most
difficult along the S coast where the marine layer could keep
conditions more stable.

A lot to consider, but have put slight chance of thunder back
in the forecast for all areas, as large area of tt in the lower
50s crosses the region. Looks like best chance of thunder will
occur between 22z and 05z. But, if the convection does indeed
get going in the vicinity of the strong low level jet, could see
some gusts with any thunderstorms. They will be few and far
between, though. Feel the best shot for thunder will occur
across central and western mass into north central CT.

Also noting a band of moderate to heavy rainfall crossing ahead
and with the front. Quantitative precipitation forecast amounts from 0.25 to 0.5 inches, with
highest amounts across the east slopes of the Berkshires. If this
does materialize, could help mix some of the strong winds down
as well even without any convection. Generally east of a kfit-
korh-kijd line, precip will be lower as the front will tend to
speed up as it crosses the region.

As the front pushes across, temps will drop quickly behind it.
The back edge of the precip will quickly follow, but could see
some mix of change over to snow across the higher inland terrain
before ending. At this Point, May see the light snow around or
after midnight for a few hours before ending. A few snow showers
may linger across the higher terrain of northwest mass.

Sunday and Monday...

Expect dry and seasonable conditions for Sunday, but blustery
northwest winds will make it feel much cooler. Expect gusts up to
around 25-30 mph with excellent low level mixing in place,
especially across the higher terrain and along the coast. Will
see temps reach the mid and upper 40s across the coastal plain,
but holding in the mid 30s to around 40 across the higher
terrain. With the cooler temps and gusty winds, wind chill
values may be below 20 degrees across the east slopes of the
Berkshires, and in the mid 20s to lower 30s elsewhere.

On Monday, high pressure ridge pushes offshore as fast
progression of weather systems continue. SW winds increase,
with gusts up to around 25-30 mph possible, highest across the
higher terrain and along the S coast. Questions on timing and
track of passing low pressure system late Mon or Mon night. 12z
GFS/European model (ecmwf) has fairly good agreement in keeping most of moisture
S of the region, but could see some widely sct showers as it
moves across. Not a lot of confidence with the evolution of this
system, however.


Leaned toward a blend of the 12z GFS/European model (ecmwf) along with their
ensembles during this timeframe, showing a bit better agreement
with timing and track of fast moving systems.

Low pres should push offshore S of New England Tuesday morning,
taking any leftover showers with it. Big questions surface with
yet another system moving across the northern stream during the
Tuesday night/Wednesday timeframe. 12z Canadian global Gem was
most aggressive with this low, likely due to its associated
cutoff 500 mb low, while the GFS and European model (ecmwf) kept a more open 500 mb wave
with it. Does look like this system should pass across the Great
Lakes, but wide variance on timing and track of this feature
keep rather low forecaster confidence.


Aviation /00z Thursday through Monday/...
forecaster confidence levels...

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

Short term /through Thursday night/...

This evening...high confidence.

VFR. Light/variable or light SW winds.

Overnight...moderate confidence.

VFR through midnight. Areas of MVFR-IFR ceilings/visibilities develop
around or after 05z in patchy fog.

Thursday...moderate confidence.

Lingering areas of MVFR-IFR ceilings and visibilities early morning with
fog dissipating/lifting. Ceilings trending to a mix of MVFR-VFR by
late morning and through the afternoon.

Thursday night...moderate confidence.

Potential for areas of MVFR and especially IFR cigs and vsbys
in low clouds and areas of fog. A cold front pushing southward
into Massachusetts late Thu night could bring scattered showers
to southern New England as well, possible decrease in clouds
north of the front.

Kbos taf...high confidence in taf thru this evening. Sea breeze
returning to a light SW wind after 00z. Moderate confidence in
taf for tonight into Thursday. There is a low chance for IFR
conditions in low clouds and fog between 06z and 12z. VFR
anticipated for Thu, SW winds should be strong enough to
prevent sea breeze development.

Kbdl taf...high confidence in taf for this afternoon, with VFR.
Moderate confidence in taf tonight into Thursday. Anticipating
MVFR vsbys generally 07z-12z in patchy fog, but there is a low
chance of IFR cigs/vsbys in fog for that timeframe.

Outlook /Friday through Monday/...

Friday...low confidence. A band of IFR ceilings/MVFR-IFR visibilities
early Fri along the S coast will shift north during the day.
Conditions lower to widespread MVFR-IFR in cigs, areas of
drizzle and patchy fog Fri night. Areas of drizzle along S

Saturday...moderate confidence. Should see widespread MVFR-IFR
conditions as rain moves in across the region. May see areas of
LIFR ceilings develop Sat afternoon/night along the coast and
interior higher terrain. Low chance for isolated thunderstorms
from 21z Sat to 04z- 05z sun as cold front passes. May see
period of light snow after midnight Sat night across higher
inland terrain as precip tapers off.

Sunday...moderate confidence. Conditions rapidly improve to VFR
by mid Morning Sun. West winds gusting to 25-30 kt, highest across
the higher terrain and along the coast.

Monday...high confidence. Mainly VFR conditions. A low chance
for showers south of the Mass Pike as weak low pressure passes
S of New England. Low chance for brief MVFR conditions in any
showers. West winds gusting to around 25 kt during the late morning
and afternoon across the higher terrain and along the coast.


forecaster confidence levels...

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

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


High pressure off the mid Atlantic coast. Near shore southeast winds
noted at buoys at 23z will shift to S-SW 5-10 knots for the
overnight. Seas 1-3 feet.

Thursday and Thursday night...

Wind speeds Thursday increase some as winds strengthen aloft.
This might be enough to bring gusts 20-25 kt to the coastal
waters Thursday afternoon. Seas may approach 5 feet on the
outer waters Thursday afternoon/evening.

Outlook /Friday through Monday/...

Friday...low confidence. Southerly flow will switch to a more
northeast to east flow during the day. Vsbys restriction
possible in fog and drizzle especially across the southern

Saturday...moderate confidence. Increasing southerly flow with
the potential for Small Craft Advisory gusts. Waves will also increase in
response. Vsbys reduced in developing rain and fog.

Sunday...high confidence. Northwest winds will keep seas up and
increase wind gusts near 30 kts. Low probability for gales
across the outer waters.


record highs for Thu Feb 23



Box watches/warnings/advisories...
Rhode Island...none.


near term...evt/nmb
short term...nmb

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