Sunrise 5:29 AM   Sunset 7:45 PM Moonrise 4:06 AM   Moonset 4:58 PM

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ANZ232 Nantucket Sound- 1004 Am Edt Sun May 5 2024
This afternoon - SE winds around 10 kt. Seas around 2 ft. Wave detail: se 2 ft at 4 seconds and E 2 ft at 10 seconds. Tonight - S winds 10 to 15 kt. Seas around 2 ft. Wave detail: se 2 ft at 4 seconds and E 2 ft at 9 seconds. Patchy fog. A chance of showers in the evening, then showers after midnight. Vsby 1 to 3 nm. Mon - S winds 15 to 20 kt, becoming sw 10 to 15 kt in the afternoon. Seas around 2 ft. Wave detail: S 2 ft at 4 seconds and E 2 ft at 10 seconds. Showers, mainly in the morning. Patchy fog in the morning with vsby 1 nm or less. Mon night - SW winds 10 to 15 kt, becoming W around 5 kt after midnight. Seas around 2 ft. Wave detail: sw 2 ft at 5 seconds and E 2 ft at 10 seconds. Tue - N winds 5 to 10 kt, becoming se in the afternoon. Seas around 2 ft in the morning, then 1 foot or less. Wave detail: E 2 ft at 11 seconds and ne 1 ft at 2 seconds, becoming ne 1 ft at 2 seconds and S 1 ft at 5 seconds. Tue night - SW winds 5 to 10 kt. Seas 1 foot or less. Wave detail: E 1 ft at 2 seconds and S 1 ft at 5 seconds. Wed through Thu night - E winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 3 ft. A chance of showers.
seas are reported as significant wave height, which is the average of the highest third of the waves. Individual wave heights may be more than twice the significant wave height.

ANZ200 1004 Am Edt Sun May 5 2024
Synopsis for massachusetts and rhode island coastal waters - High pressure begins to move east tonight, but dry weather remains through Sunday morning. Weak low pressure and its attending cold front brings rain Sunday afternoon through Monday morning. Dry weather returns Monday evening through Tuesday. Then a frontal boundary sets up over or just south of new england Wednesday into next weekend. A series of lows will likely traverse this front, bringing periods of rain, fog and onshore flow.

FXUS61 KBOX 051248 AFDBOX

Area Forecast Discussion National Weather Service Boston/Norton MA 848 AM EDT Sun May 5 2024

SYNOPSIS
Cloudy and cool weather is on tap for today with a period of widespread showers arriving from the west this afternoon and continuing overnight. Mild and dry to start the work week before cooler and unsettled conditions Wednesday through next weekend

NEAR TERM /UNTIL 6 PM THIS EVENING/

845 AM Update...

* Cloudy with showers moving into the interior mainly this afternoon & late afternoon/early evening on I-95 corridor

* Remaining cool this afternoon with highs only in the 50s

Previous forecast is pretty much on track. High pressure over the Canadian Maritimes will continue to shift further east today as shortwave energy approaches from the west. The stronger/forcing deeper moisture will not impact the interior until this afternoon. So while a few spot showers are possible this morning across the interior...expect the main threat of showers to arrive this afternoon
Meanwhile
in the Boston to Providence corridor the showers should not arrive until late afternoon/early evening but it still will be cloudy.

As for temperatures...they will remain cool today with cloudy skies and onshore low level flow. This should keep high temperatures in the 50s across the vast majority of the region.

SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/

Tonight

Showers associated with an upper-level short-wave traversing over The Northeast spread west to east this evening. Expect widespread light showers across southern New England with new rainfall accumulations totaling 0.25 to 0.5 inches. Winds remain steady out of the south which will keep dewpoints elevated and support some patchy fog formation. Low temps will be bottom out early in the evening as southerly flow and low-level warm advection will begin to support increasing temperatures after midnight and into tomorrow morning.

Tomorrow

A substantial warm up tomorrow as southerly flow advects a near 15C air mass at 925 hPa over the region. Still expecting a good amount of low to mid-level cloud cover across the region for the first half of the day, but breaks of sun in the afternoon should support warm temperatures in the low to mid 70s across areas of southern New England away from the coast. Winds may be light enough to support a sea-breeze along the coastline which would result in cooler temperatures in the mid 60s.

LONG TERM /MONDAY NIGHT THROUGH SATURDAY/
* Dry with warmer than normal temperatures Tuesday

* Cooler with periodic showers Wednesday thru Saturday

Temperatures...

Warm airmass over SNE with good model consensus of 925 mb temps ranging from +16C to +18C...and +10C at 850 mb. These temps aloft combined with good blyr mixing via strong/high May sun angle and a dry airmass (dew pts in the 40s) will support highs 75-80. Ensembles have 100% probability of 70+ temps away from the immediate coast Tue. These temps are much warmer than normal (60s) for early May.
Thus, a dry heat for Tue. A weak pressure gradient combined with ocean temps in the 40s, will result in a wicked seabreeze, hence much cooler along the coast, Cape and Islands. However, coastal locations including Boston, could briefly hit 70+ before the seabreeze arrives. Nonetheless, Tue definitely the pick of the week, then a pattern change develops around Wednesday and continues thru next weekend. A stalled frontal boundary sets up over or near SNE, yielding a cooler regime, with lots of clouds, onshore flow and risk of showers from time to time. Temps likely become progressively cooler each day, beginning Wed and continuing into next weekend.

Precipitation...

Any leftover scattered showers Monday evening associated with weak cold front, quickly come to an end as post frontal airmass overspreads the region later in the evening and overnight. Turning less humid Monday night, as dew pts fall from 55-60 into the upper 40s/low 50s by 12z Tue. Dry NW flow prevails Tue followed by a pattern change with a stalled frontal boundary setting up over or near SNE, beginning Wed and continuing into next weekend. Lots of uncertainty on the exact placement of this boundary and timing and amplitude of frontal waves traversing this boundary. There will be periods of dry weather during this time as well, hence not raining every hour of the day.

AVIATION /13Z SUNDAY THROUGH THURSDAY/
Forecast Confidence Levels:

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

12z TAF Update...

Marginal MVFR/IFR will slowly lift to mainly MVFR but then likely lower this afternoon and especially late in the day as showers overspread the region from west to east. Light E-SE winds. Earlier discussion below.

---------------------------------------------------------------

Borderline IFR/MVFR ceilings between 008-012 feet with light easterly winds.

Sunday...High Confidence.

IFR/MVFR ceilings will trend to mainly MVFR thresholds with some diurnal heating despite the cloudy skies. Some showers will work into mainly interior MA & CT during the afternoon hours, but will not reach the coastal plain until late Sunday afternoon/evening. SE winds 5 to 10 knots.

Sunday night...Moderate Confidence.

IFR/LIFR ceilings develop with light showers spreading west to east across southern New England overnight. SE winds shift to more of a S direction at 5 to 10 knots.

Monday...

IFR ceilings lifting to VFR levels by late morning/early afternoon. Though lower IFR ceilings may persist longer over The Cape Islands. Light southwest winds becoming more westerly.
Winds may be weak enough to support a sea-breeze circulation along the coastline.

KBOS TAF...High confidence

KBDL TAF...High confidence

Outlook /Monday Night through Thursday/...

Monday Night through Tuesday: VFR.

Tuesday Night: Mainly VFR, with local MVFR possible. Slight chance SHRA.

Wednesday: Mainly MVFR, with local IFR possible. Breezy. Chance SHRA, isolated TSRA.

Wednesday Night: Mainly VFR, with local IFR possible. Breezy.
Chance SHRA.

Thursday: Mainly VFR, with areas MVFR possible. Breezy. Chance SHRA.

MARINE
Forecaster Confidence Levels:

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

Today through Tomorrow

Seas increase by about a foot over the next 48 hours as winds become more steady out of the south. Nonetheless, conditions remain on the quiet side with wind speeds topping out at 10-15 knots and seas in the 2 to 4 foot range. A period of stronger gusts up to 20 knots is expected to develop tomorrow afternoon over the outer southeastern marine zones.

Outlook /Monday Night through Thursday/...

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

Tuesday through Tuesday Night: Winds less than 25 kt.

Wednesday: Winds less than 25 kt. Chance of rain showers, isolated thunderstorms.

Wednesday Night: Winds less than 25 kt. Areas of seas approaching 5 ft. Slight chance of rain showers.

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

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

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Dennis Port
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Sun -- 03:51 AM EDT     -0.04 feet Low Tide
Sun -- 04:06 AM EDT     Moonrise
Sun -- 05:31 AM EDT     Sunrise
Sun -- 10:28 AM EDT     3.74 feet High Tide
Sun -- 04:14 PM EDT     -0.12 feet Low Tide
Sun -- 04:58 PM EDT     Moonset
Sun -- 07:43 PM EDT     Sunset
Sun -- 10:55 PM EDT     3.99 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION

Dennis Port, Nantucket Sound, Massachusetts, Tide feet

Pollock Rip Channel
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Sun -- 01:12 AM EDT     0.00 knots Slack
Sun -- 04:05 AM EDT     Moonrise
Sun -- 04:37 AM EDT     1.97 knots Max Flood
Sun -- 05:31 AM EDT     Sunrise
Sun -- 07:40 AM EDT     -0.00 knots Slack
Sun -- 10:27 AM EDT     -1.81 knots Max Ebb
Sun -- 01:33 PM EDT     0.00 knots Slack
Sun -- 04:57 PM EDT     Moonset
Sun -- 05:02 PM EDT     2.14 knots Max Flood
Sun -- 07:42 PM EDT     Sunset
Sun -- 08:09 PM EDT     -0.00 knots Slack
Sun -- 10:57 PM EDT     -1.88 knots Max Ebb
Tide / Current data from XTide NOT FOR NAVIGATION

Pollock Rip Channel, Massachusetts Current, knots

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