395
FXUS61 KBOX 300644
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
244 AM EDT Mon Sep 30 2024

.SYNOPSIS...

High pressure continues to provide dry conditions to the region for
the start of the work week. Low chance for a shower mid-week,
followed by continued dry conditions as high pressure will bring a
return to dry and seasonable weather later in the week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...

Patchy radiation fog that formed overnight should burn off shortly
after 8 am this morning, but skies wont stay clear for long. Another
thick deck of high cirrus clouds begins to move in later this
morning as the once stalled closed low breaks down and moves just
offshore to the south.  With high pressure to the north, winds turn
NE again today. With onshore flow, overcast skies, and 850 temps
dropping to +7C, trended high temps cooler than the NBM into the
upper 60s to low 70s for today.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...

Onshore flow continues overnight. With high-level cirrus and
some easterly surface flow, radiation fog should be much more
localized. There could be another marine stratus deck that forms
overnight. With less than ideal radiational cooling conditions,
overnight lows should stay in the low to mid-50s vs. the mid to
upper 40s.

More of the same weather on Tuesday as the surface and upper-level
pattern hardly change. Low to mid-level stratus should burn off
by the afternoon, but skies remain mostly cloudy with the high
cirrus deck remaining overhead. Winds increase to 10-15 mph
from the ENE as the pressure gradient tightens slightly. High
temps moderate back down to the low to mid-60s, except in the CT
river valley where upper 60s to low 70s are possible.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...

Highlights...

* Mostly dry & pleasant weather continues through the end of the
  week.

* First chance of rain showers comes late Wednesday but chance of
  rain has steadily been decreasing over the last 48 hours and most
  locations likely stay dry.

*  Next chance of rain arrives on Saturday.

Details...

Good news for those with outdoor activities planned on Wednesday as
the trend over the last 48-72 hours with our mid week frontal system
has been slower and drier, to the point that most in southern New
England likely won`t see any rain at all. The high pressure ridge
overhead, extending from Nova Scotia, will remain strong enough to
keep Helene`s remnants removed to the south and the Great Lakes
trough confined to northern New England. The best shot of seeing any
rain Wednesday night will be in far northwest MA in closer proximity
to said dynamics. By the latter half of the week mid level heights
will begin to rise as surface high pressure builds in further,
keeping the forecast dry. This also means temps will be quite a bit
warmer Thu/Fri as previously cool onshore flow becomes southwest and
the building 850 me ridge takes the airmass at 850 mb from +6C on
Wednesday to +12C by Thu/Fri. High temperatures will increase from
the 60s Wednesday to the mid to upper 70s on Thu/Fri.

Looking ahead at next weekend guidance is in pretty good agreement
that another shortwave swings through on Saturday bringing a cooler
and wetter forecast fore the first half of the weekend followed by a
drier Sunday. Of course, timing of this feature can change as we get
closer to the weekend so check back as we get more information and
the forecast is adjusted accordingly.

&&

.AVIATION /07Z MONDAY THROUGH FRIDAY/...
Forecast Confidence Levels:

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

Rest of this morning...Moderate confidence.

Quite a bit of radiation fog already showing up on satellite
for much of interior SNE. Added tempo groups for off and on fog
this morning. Expecting fog to burn off around 12-13z in the
morning

Today...High confidence.

VFR after the fog burns off with light winds at 5-10 knots from
the ENE. MVFR stratus deck may hang over the Cape and Islands
into the afternoon.

Tonight...Moderate confidence.

Should be less fog around with a thick high cirrus deck
overhead, however, guidance is hinting at another MVFR stratus
deck forming over Eastern MA and RI.

Tomorrow...Moderate confidence.

MVFR stratus deck should lift and break up by mid morning with
VFR conditions by the afternoon. The only uncertainty is that
winds pick up to 10-15 knots out of the east, which may keep the
low to mid level cloud deck around.


BOS TAF...Moderate Confidence in TAF.

Mainly VFR, with a chance at fog forming early this morning. If
fog does form, it will likely burn off by 12z. Winds turn ENE
today at 5-10 knots.

BDL TAF...Moderate Confidence in TAF.

Intermittent fog this morning before things begin to clear to
VFR by 12-13z. Winds stay light out of the NNE.

Outlook /Tuesday Night through Friday/...

Tuesday Night: Mainly VFR, with local MVFR possible.

Wednesday through Friday: VFR.

&&

.MARINE...
Forecaster Confidence Levels:

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

Through Tuesday...High confidence.

Tranquil boating conditions today have light ENE winds at 5-10 knots
and gusts of 15 knots in the southern waters.  Seas today remain 1-3
feet.  Winds increase out of the east on Tuesday, gusting up to 20
knots, especially in the southern waters. Seas increase to 3-4
feet.

Outlook /Tuesday Night through Friday/...

Tuesday Night through Thursday: Winds less than 25 kt. Areas of
seas approaching 5 ft.

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

Friday: Winds less than 25 kt.

&&

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

&&

$$

SYNOPSIS...BW/KP
NEAR TERM...KP
SHORT TERM...KP
LONG TERM...BW
AVIATION...BW/KP
MARINE...BW/KP