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ANZ232 Nantucket Sound- 401 Pm Est Mon Dec 11 2023
.small craft advisory in effect through Tuesday afternoon...
Tonight..W winds 20 to 25 kt, diminishing to 15 to 20 kt after midnight. Gusts up to 30 kt. Seas 4 to 7 ft.
Tue..W winds 10 to 15 kt with gusts up to 20 kt. Seas 3 to 5 ft.
Tue night..SW winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to 4 ft.
Wed..W winds 15 to 20 kt. Seas 2 to 4 ft.
Wed night through Thu night..W winds 20 to 25 kt. Seas 2 to 3 ft.
Fri through Sat night..E winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to 3 ft.
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 401 Pm Est Mon Dec 11 2023
Synopsis for massachusetts and rhode island coastal waters.. Conditions gradually improve on Tues as high pres builds S of the waters. A cold front will cross the waters on Wed followed by high pres building to the south Thu into Fri.

FXUS61 KBOX 111933 AFDBOX

Area Forecast Discussion National Weather Service Boston/Norton MA 233 PM EST Mon Dec 11 2023

SYNOPSIS

Dry weather should prevail this week. A cool down through mid week will give way to milder temperatures later in the week and next weekend.

NEAR TERM /THROUGH TONIGHT/

Cold front that swept our efficient rainmaker out to sea this morning continues to push out to sea, allowing for much drier air to filter in on strong NW flow. The drying column will allow for skies to clear quickly this evening with the exception being across the high terrain of the Berkshires where topography is able to retain cloud cover overnight. Given brisk 925mb winds of 25 to 35kt remain pinned over southern New England, 15-20kt winds are expected to mix to the surface much of the overnight, with higher gusts not out of the question for the Worcester Hills and downslopes of the Berkshires. Given winds remaining elevated overnight, not expecting the boundary layer will decouple with lows in the 20s to low 30s driven by strong CAA advection than radiational cooling.

SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/

High pressure builds south of southern New England across the Carolinas/Virginia as weak ridging also develops to our east on which will allow flow to shift to the southwest starting around sunrise. Not anticipated much by way of strong WAA given weak synoptic influence on flow, but temperatures should range around to slightly above normal, in the low to mid 40s. Abundant sunshine will be a treat for many across southern New England after what seems like days of clouds.

Winds again fail to decouple overnight Tuesday which again limits the radiational cooling potential with slightly above normal lows forecasted in the upper 20s northwest to mid and upper 30s across the Cape. Broad trough that will pass to our north later this week begins to move in from the northwest, which will shift winds back to the NW overnight.

LONG TERM /WEDNESDAY THROUGH MONDAY/

Key Points: - Mainly dry weather expected.
- Brief cooldown then turning milder by next weekend.

Overall a quiet weather pattern is expected to prevail through next weekend. Models/ensembles showing good agreement in upper level pattern with broad trough in place over Northeast which shifts into Maritimes later in week. This will allow for some upper riding to work into region later in week, bringing somewhat milder temperatures, but not to extent that we just experienced, more like a little above average for mid December (40s/lower 50s).

Early next week, we see differences emerge in upper pattern across eastern US in regard to southern stream closed low heading from southern Plains to the Gulf Coast. GFS/Canadian ensembles show more interaction with northern stream trough than does ECMWF and its ensembles, resulting in coastal low that tracks near or through southern New England (preliminary indications showing mainly rain).
For now we will follow NBM which brings chance PoPs into RI and eastern MA, but expect to see changes over next few days as this possible interaction becomes better resolved.

AVIATION /20Z MONDAY THROUGH SATURDAY/
Forecast Confidence Levels:

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

18Z Update...

High confidence in trends, moderate confidence in timing of VFR development.

Through tonight...

Conditions will continue to improve across all terminals this afternoon and early evening with a transition from MVFR to VFR over the next two to three hours. Anticipating all terminals will be VFR by 22Z. Gusty NW flow maintains 20-25kt through sunset before diminishing slightly to 15kt overnight. Gusts will be slowest to diminish over the high terrain.

Tomorrow and tomorrow night... High Confidence

VFR through the period as winds become more SW around daybreak Tuesday. Winds generally 10kt with gusts to 15kt. Tranquil conditions and SW flow continue overnight.

KBOS Terminal...High confidence in trends. Moderate confidence in timing.

KBDL Terminal...High confidence.

Outlook /Wednesday through Saturday/...

Wednesday: VFR. Windy with local gusts up to 30 kt.

Wednesday Night through Saturday: VFR. Breezy.

MARINE
Forecaster Confidence Levels:

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

based on the latest observed trends, confined the Storm Warning to the outer coastal waters, as well as Nantucket Sound. Gale Warnings elsewhere, but only through 7 AM for Boston Harbor and Mass Bay, as well as Narragansett Bay and Block Island Sound.
Remaining Gale Warnings continue into mid morning. Further headline changes expected with later forecasts today as winds continue to diminish slowly.

249 AM Update...

A cold front was quickly approaching the waters this morning.
Winds were just starting to ramp up across the waters. Starting to think we may not quite get to storm-force winds, but the threat remains. Winds were southerly at 88 kt at 2,000-2,500 ft above ground, and it would not take much more mixing to bring some of this down to the surface. Will maintain the Storm Warnings for now, and continue to monitor. May be able to downgrade to Gale Warnings later this morning.

Moderate to heavy rainfall will reduce visibility at times this morning. An abrupt and significant shift in winds is expected as this cold front crosses the waters. Seas gradually diminish through the day, but seas will still be rough on the waters into Tuesday.

Outlook /Wednesday through Saturday/...

Wednesday: Winds less than 25 kt. Seas up to 5 ft.

Wednesday Night: Moderate risk for Small Craft Advisory winds with local gusts up to 30 kt. Seas up to 5 ft.

Thursday through Thursday Night: Low risk for Small Craft Advisory winds with gusts up to 25 kt. Areas of seas approaching 5 ft.

Friday: Moderate risk for Small Craft Advisory winds with gusts up to 25 kt. Areas of seas approaching 5 ft.

Friday Night: Moderate risk for Small Craft Advisory winds with gusts up to 25 kt. Seas locally approaching 5 ft.

Saturday: Winds less than 25 kt.

HYDROLOGY

Attention now turns to flooding on larger rivers which typically take longer to respond from heavy rainfall. Now that the rain has fallen we need to assess how much runoff gets into the drainage basins.

Flood Warnings have been posted for: - Pawtuxet River at Cranston, RI (Moderate flooding)
- Blackstone River at Woonsocket, RI (Minor flooding)
- Wood River at Hope Valley, RI (Minor flooding)
- Sudbury River at Saxonville, MA (Minor flooding)

We're also keeping an eye on other rivers which are either forecast to just reach flood stage (FS) or forecast to reach FS beyond 36 hours. These include: - Assabet River at Maynard, MA (crest at FS Tue evening)
- Connecticut River at Hartford, CT (crest near FS Wed morning)
- Connecticut River at Middle Haddam, CT (minor flood Wed morning)

Other rivers either have crested or will crest over next day or so.
Dry weather is expected for the rest of the week.



BOX WATCHES/WARNINGS/ADVISORIES
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory until 7 PM EST this evening for ANZ230- 231-236.
Small Craft Advisory until 3 PM EST Tuesday for ANZ232>235-237.
Small Craft Advisory until 7 PM EST Tuesday for ANZ250-254>256.
Small Craft Advisory until 5 AM EST Tuesday for ANZ251.

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Hyannis Port
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Mon -- 03:55 AM EST     0.21 feet Low Tide
Mon -- 05:38 AM EST     Moonrise
Mon -- 06:57 AM EST     Sunrise
Mon -- 10:32 AM EST     3.33 feet High Tide
Mon -- 02:53 PM EST     Moonset
Mon -- 04:10 PM EST     Sunset
Mon -- 04:33 PM EST     -0.14 feet Low Tide
Mon -- 11:10 PM EST     2.92 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION

Hyannis Port, Nantucket Sound, Massachusetts, Tide feet

Pollock Rip Channel
Click for Map
Mon -- 01:22 AM EST     0.00 knots Slack
Mon -- 04:41 AM EST     1.80 knots Max Flood
Mon -- 05:36 AM EST     Moonrise
Mon -- 06:56 AM EST     Sunrise
Mon -- 07:48 AM EST     -0.00 knots Slack
Mon -- 10:32 AM EST     -1.77 knots Max Ebb
Mon -- 01:41 PM EST     0.00 knots Slack
Mon -- 02:52 PM EST     Moonset
Mon -- 04:09 PM EST     Sunset
Mon -- 05:07 PM EST     2.02 knots Max Flood
Mon -- 08:24 PM EST     -0.00 knots Slack
Mon -- 11:00 PM EST     -1.63 knots Max Ebb
Tide / Current data from XTide NOT FOR NAVIGATION

Pollock Rip Channel, Massachusetts Current, knots

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