000 
fxus61 kbox 190822 
afdbox 


Area forecast discussion 
National Weather Service Boston/Norton Massachusetts 
422 am EDT Tue Jun 19 2018 


Synopsis... 


Seasonable, dry, comfortable conditions with lower humidity today. 
Low pressure passes off the South Coast Wednesday, with a chance 
of showers along the coast. High pressure from Canada brings dry 
weather Thursday and Friday. A cold front them brings a chance of 
showers over the weekend, followed by dry weather early next week. 


&& 


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


4 am update... 


Surface cold front just moving into north Massachusetts. Ahead of, a muggy, 
humid airmass remains with dewpoints in the 60s that have 
allowed overnight temperatures to remain stable. The overall 
moist environment, undergoing minor to moderate forcing, is 
yielding some scattered shower activity along with low clouds as 
dense fog lingers along the S-coast. Nuisance variety, perhaps 
some visibility issues along area roadways with the am commute. 
Behind the front much drier air, with latest satellite trends 
over north New England showing the scouring of cloud decks. Clearing 
trend S into the morning hours, lowest conditions hanging along 
the S-coast longest. Have the cold frontal boundary pushing off- 
shore roughly around 8 am. SW winds with gusts up around 20 mph 
persist prior to the front, will back out of the north with passage 
and remain blustery. Should see the conclusion of locally dense 
fog along the immediate S-coast if not already. 


Today... 


Clearing out and improving immediately behind the cold front. High 
pressure building in from the west round which accompanying N, breezy 
flow allows for steep boundary layer lapse rates up to h85, enough 
to mix down faster momentum from the lingering pressure gradient 
associated with the low lifting NE against the building high, as 
well as drier air. Prevailing dewpoints with a mix of available 
guidance along with model sounding mix-down dewpoints. More 
seasonable, drier weather in store, highs upper 70s to low 80s, 
some mid 80 readings not out of the question with dewpoints 
around the upper 40s to low 50s. Comfortable to put it simply. 


&& 


Short term /6 PM this evening through 6 PM Wednesday/... 


Tonight... 


Radiational cooling. High pressure in control. Light winds, mostly 
clear conditions, leaning with coolest of MOS guidance. Talking 
lows around the upper 40s to low 50s. No need for the ac, open 
your windows. 


Wednesday... 


Mainly a dry, seasonable day under the continued weight of high 
pressure. Shifting to the E, return S flow late, however light 
enough to allow east-coastal sea-breezes. Meanwhile, weak, fast-moving 
disturbance emerging out of the Ohio River valley. Isentropic-ascent 
ahead of a re-enforcing cold front out of Canada, looking at 
increasing clouds towards Wednesday evening initially, any skirting 
rain to hold off later. Again, dry forecast. 


&& 


Long term /Wednesday night through Monday/... 


Mid level flow pattern remains fairly stable through the end of 
this work week, then should undergo more significant changes 
this weekend into early next week. These changes will be 
predicated upon the timing of some shortwave energy to phase 
with a more persistent mid level trough over southeast Canada. 
Decent amount of spread in the ensembles, as well as among the 
operational guidance. Forecast confidence is high through 
Friday, trending to moderate for this weekend and early next 
week. 


Low pressure should pass by far enough to our south Wednesday 
night into Thursday where only a chance of showers along the 
South Coast. High pressure arrives later Thursday and should 
linger through Friday. Will keep a mention for a chance of 
showers this weekend, but will not try to narrow the window of 
these showers much. This will depend upon the timing of 
shortwave energy crossing the County. More changes to this 
timing are very possible, if not likely. Drier weather should 
develop for early next week. 


Otherwise, temperatures are expected to be near to slightly 
above normal, depending upon how much sunshine we get. Humidity 
start out fairly comfortable, then should increase into this 
weekend. 


&& 


Aviation /08z 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/...moderate confidence. 


Through morning... 


SW winds prevailing, gusts up around 25 kts especially S-coastal 
terminals beneath low level wind shear with winds 2 kft agl upwards of 50 kts. 
In addition, scattered -shra, tempo MVFR-IFR cigs and vsbys aside from 
areas of fog along immediate S-coastal terminals. With north wind 
shift, immediate improvement towards VFR. Improving trend expected 
with the morning push towards 12z at which time most if not all 
terminals should be observing north winds, the exception being ack. 


Today... 
VFR. North winds, gusty up around 20 kts at times. 


Tonight.. 
VFR. However conditions just right within sheltered valleys, may 
see some spotty IFR-LIFR conditions with fog. Higher confidence 
in mid to upper CT River Valley. 


Wednesday... 
VFR. Overall light winds becoming S/SW. Allowance for east-coastal 
sea-breezes to develop around 15z. Increasing mid-upper level 
cigs late. 


Kbos terminal... 
hold VFR throughout, however can't rule out a brief period of 
MVFR into the morning push. Wind shift at the terminal around 
915z. Northwest flow through the day, gusts up to 20 kts. 


Kbdl terminal... 
maintain VFR however not ruling out MVFR when observing upstream 
trends presently over northwest Massachusetts. An opportunity during the morning 
push before clearing out. Wind shift at the terminal around 940z. 


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


Wednesday night: VFR. Breezy. Slight chance rain showers. 


Thursday through Friday night: VFR. 


Saturday: VFR. Chance rain showers. 


&& 


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. 


Cold front pushing across the east waters this early morning, into 
the S-waters roughly around 8 am. SW flow in advance with gusts 
upwards of 25 kts will keep wave heights 4-5 feet on the outer 
waters. Winds shifting north with passage, remaining brisk with gusts 
up to 20 kts, however high pressure building in from the W, should 
allow for seas to diminish through afternoon and subsequent 
conclusion of small craft advisories. Overnight and into Wednesday, 
high pressure in control yielding light winds, good boating 
weather. East onshore sea-breeze flow Wednesday. 


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


Wednesday night: winds less than 25 kt. Chance of rain showers. 


Thursday through Friday night: winds less than 25 kt. 


Saturday: winds less than 25 kt. Chance of rain showers. 


&& 


Box watches/warnings/advisories... 


CT...none. 
Massachusetts...none. 
Rhode Island...none. 
Marine...Small Craft Advisory until 2 PM EDT this afternoon for 
anz254>256. 


&& 


$$ 


Synopsis...Belk/sipprell 



National Weather Service Glossary of Abbreviations
Back to forecast page
Non-Expanded Version (with abbreviations)

Units: English | Metric

Find the Weather for any City, State or Zipcode, or Country:

U.S. State List | Severe Weather | Tropical Storms | Ski Conditions
United States | Canada | Central America | South America | Asia | Europe | Australia | Africa | Islands

Weather Underground

© Copyright 2018
The Weather Company, LLC