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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KBOX 211536
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
1136 AM EDT Thu Jun 21 2018

.SYNOPSIS...
Low pressure near the New Jersey coast early this morning will
bring an area of showers across southern areas, which should
push offshore by midday. Another weak weather system may bring
some spotty showers across central and eastern areas this
afternoon. High pressure will bring dry conditions but a bit
cooler temperatures on Friday. Unsettled conditions Saturday,
continuing through early Monday with the chance of showers and
thunderstorms. Dry weather expected Tuesday and Wednesday.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
10 am Update...

Forecast is in good shape.

Last of showers exiting South Coast, which will be followed by
clearing early this afternoon. Still expecting scattered
showers this afternoon as short wave rotates through SNE and
combines with sufficient moisture and some instability (CAPE
around 100-300 J/kg). Continuing with 30-40% PoPs which is in
line with high-res guidance.

Bumped up temperatures a few degrees based upon latest
observations. Many interior spots should reach lower 80s.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
Tonight...
Expect conditions to be mostly clear away from coastal areas
tonight. E-NE winds will continue with the high to the N, so
low level moisture will remain. Brought in low clouds and fog
especially along the coast, but could push further inland as
well. Should see lower conditions along the immediate coast.

Temps will fall back through the 50s, though may hold on close
to 60 in the urban centers.

Friday...
Any coastal fog should dissipate by mid morning or so.
Otherwise, high pressure remains in control with mostly clear
conditions. It will remain cool especially along the coast with
continued onshore winds.

&&

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
*/ Highlights...

 - Saturday perhaps not a washout, skirting rains S/E
 - Showers / t`storms N/W Sunday, sweeping SE into Monday morning
 - Prolonged dry conditions during the week
 - Watching weeks-end for additional wet-weather disturbances

*/ Overview...

Pattern this weekend should feature above normal precipitable
water. Precipitable water values drop off to near to below
normal levels early next week. Temperatures on the other hand
should remain near normal, except for Saturday, and perhaps
Monday.

Split mid level flow regime should merge into a more unified
flow across much of the towards Monday. It appears likely the
pattern will transition from a potent mid level low over
northern Quebec with a weaker cutoff over Indiana to start this
weekend, to one which features a more amplified mid level trough
by Monday. This trough should move over the North Atlantic
towards the middle of next week.

At the surface, this should mean a low pressure moving through
the Great Lakes towards northern New England this weekend. While
not a total washout, we will have at least a chance for showers
this weekend. A secondary cold front, along with a mid level
shortwave, should be enough to cause showers to linger into
Monday. This timing may change with later forecasts. Instability
is enough to warrant a mention of at least a few thunderstorms
at times this weekend.

High pressure with drier weather Tuesday into Wednesday.

&&

.AVIATION /16Z THURSDAY THROUGH MONDAY/...
Forecaster Confidence Levels...

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

* Updated 1135 AM *

Short Term /through Friday/...High confidence.

Amended ACK for impending IFR ceilings which arrive early this
afternoon and persist into Friday morning. IFR or even LIFR
conditions should affect much of South Coast, Cape Cod, MVY, and
BID as well, especially later this afternoon.

Otherwise VFR through afternoon as showers depart South Coast
and scattered showers develop across interior SNE. Winds
gradually shift to E/NE at 10kt or less.

Tonight...
Mainly VFR. MVFR CIGS along SE coastal areas with the E-NE
winds in place. Patchy fog with areas of MVFR VSBYS move onshore
mainly across E Mass into RI.

Friday...
Mainly VFR, but with E winds lingering, may see lower clouds
linger across E coastal areas with local MVFR conditions
possible.

KBOS Terminal...High confidence in TAF. VFR through the evening
push, then some MVFR CIGS/VSBYS may work in after 03Z-04Z Fri.

KBDL Terminal...High confidence in TAF. Showers and lower
clouds/patchy fog pass S of the terminal. VFR conditions.

Outlook /Friday Night through Monday/...Moderate confidence.

Friday: VFR.

Friday Night: VFR. Breezy. Chance SHRA.

Saturday: Mainly VFR, with local MVFR possible. Breezy. Chance
SHRA, isolated TSRA.

Saturday Night: MVFR/IFR conditions possible. SHRA likely,
slight chance TSRA.

Sunday: Mainly VFR, with local IFR possible. Chance SHRA,
isolated TSRA.

Sunday Night: Mainly VFR, with local MVFR possible. Chance
SHRA, isolated TSRA.

Monday: VFR. Breezy. Chance SHRA.

&&

.MARINE...
Forecaster Confidence Levels...

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

Short Term /through Friday/...High confidence.

Today...Low pressure will pass across the southern outer waters
with showers and patchy fog that will reduce visibility to 1-3
nm at times through midday or early this afternoon. Seas 3 ft
or less. Light W winds will shift to E-NE with gusts briefly up
to 20 kt.

Tonight and Friday...High pressure will build N of the waters,
keeping a E-NE wind flow in place through most of this
timeframe. May see occasional gusts to 20 kt at times. Seas up
to 3 ft, though may approach 4 ft at times across the southern
waters Fri. Areas of fog will reduce visibility tonight into
Friday morning.

Outlook /Friday Night through Monday/...Moderate confidence.

Friday: Winds less than 25 kt. Seas locally approaching 5 ft.

Friday Night: Winds less than 25 kt. Areas of seas approaching
5 ft. Chance of rain showers.

Saturday: Winds less than 25 kt. Areas of seas approaching
5 ft. Chance of rain showers, isolated thunderstorms.

Saturday Night: Winds less than 25 kt. Areas of seas
approaching 5 ft. Rain showers likely, slight chance of
thunderstorms.

Sunday through Sunday Night: Winds less than 25 kt. Local rough
seas. Slight chance of rain showers, isolated thunderstorms.

Monday: Winds less than 25 kt. Seas up to 5 ft. Chance of rain
showers.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...None.

&&

$$
SYNOPSIS...Belk/EVT
NEAR TERM...JWD
SHORT TERM...EVT
LONG TERM...Belk
AVIATION...JWD
MARINE...Belk/EVT