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Area forecast discussion 
National Weather Service Taunton Massachusetts
1117 am EDT Sat may 23 2015

high pressure will build to the Middle Atlantic States today...
bringing cooler air to the region. Warm and muggy conditions
to build across the region beneath high pressure into next week.
Should remain mostly dry with the better chances for wet-weather
to remain mainly north and west of our area prior to the following


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

11 am update...
skies remain mainly clear across the region late this morning
except for a few fair weather clouds. Good subsidence in place as
high pressure builds off the New Jersey coast. Good mixing to 850 mb also in
place though noting winds at or above ground level also diminish as ridge
builds in this afternoon. Still some gusts to around 20 knots along
the immediate East Coast as well as on Cape Cod and Nantucket at 15z.

Temperatures have rebounded nicely after chilly early morning lows.
Noting readings mainly in the Lower-Middle 50s. Winds also starting
to back to west as they diminish...which will continue this

Dewpoints have dropped back to upper teens to lower 20s across the
region...a bit higher across the cape and islands. Have updated
the dewpoints to lower just a tad from previous forecast...which
lowered the relative humidity/S to between 15-20 percent inland and 20-30 percent
along the coast. Forecasted highs in the upper 50s to lower 60s
remain in line.

Remainder of forecast in good shape but have updated to bring
conditions current. Held off on this until near shore waters small
craft ended at 11 am.


Short term /6 PM this evening through 6 PM Sunday/...
SW flow gets underway tonight as high pressure becomes positioned
offshore. Should see some middle level cloudiness tonight in
association with weak short wave passing through...but lower
levels remain Bone dry so no rainfall is expected. Lows should
fall back into 40s and lower 50s.

Warmup starts sun with increasing SW flow and subsidence in wake
of departing short wave. Model 2m temperatures support highs well
into 70s or around 80 away from S coast...where temperatures
should be held in 60s to near 70.


Long term /Sunday night through Friday/...
*/ highlights...

- looking good for Memorial Day
- wet-weather chances across north/W-portions of the NE Continental U.S. Through the week
- warm and muggy pattern evolving
- the return of an active wet-weather pattern by next weekend

*/ discussion...

Long-term pattern more apparent with run-to-run consistency of model
forecast guidance. Ridge enhances over the east-Continental U.S. Ahead of an open-
wave west-Continental U.S. Trough. With the Bermuda high maintained the low-to middle-
level convergent flow up against the north-Canada vortex is kept north/west of
S New England through which middle-level energy stretches providing
forcing of SW-isentropic ascent of the warm-moist conveyor belt.
Subsidence and dry-air beneath anticyclonic flow is affirmed for S
New England. Anticipating a warm-muggy-dry pattern through the end
of the week prior to the ridge eroding up against the cut-off
retrograding low through the NW-Atlantic. With the ridge eroding
it is more likely that middle-level energy and convergent flow can
slip southward putting S New England in an active weather pattern
perhaps by next weekend.

So will continue with higher pop-chances north/west keeping a majority of
the forecast period dry. Steering flow mainly W/SW. S-flow beneath
high pressure/subsidence will lean with muggy unseasonably-warm
temperatures as we go into the week. May have to deal with periods
of marine stratus/fog as S-flow advects higher dewpoint air north across
the cooler waters. Focus on the overnight into morning periods. Will
hint at a shift in the weather pattern by the end of next weekend.


Aviation /15z Saturday through Wednesday/...
forecaster confidence levels...

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

Short term /through Sunday/...high confidence.

12z major changes.

West/northwest winds gust 20-25 knots through midday...before winds back to
west/SW and diminish this afternoon and tonight. SW winds gust to
20-25 knots sun...especially near S coast. VFR through period.

Kbos terminal...high confidence in taf. West/northwest flow.

Kbdl terminal...high confidence in taf.

Outlook...Sunday night through Wednesday night...

Moderate confidence. Mainly VFR. Lowest ceilings mainly N/W. SW-winds
blustery at times during daytime periods. Low confidence with IFR-
LIFR marine stratus / fog across the S/se-coast occurring during the
overnight into morning periods.


forecaster confidence levels...

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

Short term /through Sunday/...high confidence.

11 am update...

Winds and seas have diminished along the near shore waters so
allowed small crafts to expire. Seas remain at 5-6 feet on the outer
waters...especially on the eastern outer waters /around 6 feet at
buoy 44018 east of Nantucket/ so extended a little bit longer there.

Winds will continue to diminish as they back to west-SW during the

Lighter SW flow expected tonight with increasing SW winds sun
which may reach Small Craft Advisory...especially on S coastal bays and sounds.

Outlook...Sunday night through Wednesday night...

Moderate confidence. Persistent SW-fetch with daytime gusts around
20-25 kts especially along the shores and inner-waters will result in wave
heights in excess of 5-feet mostly on the outer waters. Low
confidence on the potential for marine fog during the overnight into
morning periods.


Fire weather...
west-northwest winds gust to 25 miles per hour at times...especially through midday
before diminishing. Minimum relative humidity drops to 10 to 20 percent this
afternoon across much of southern New England. Although we are
farther along in Greenup...due to lack of significant rainfall
over past several days and information from state fire
officials... Special Weather Statement has been issued for
elevated fire weather risk today.

Dry pattern may persist for next few days...although relative humidity will be
somewhat higher due to SW flow.


Box watches/warnings/advisories...
Rhode Island...none.
Marine...Small Craft Advisory until 2 PM EDT this afternoon for anz250-
Small Craft Advisory until 1 PM EDT this afternoon for anz255-


near term...sipprell/evt
short term...jwd
long term...sipprell
fire weather...staff

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