Thursday, July2, 2020
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Marine Weather and Tides
North Plymouth, MA

Version 3.4
NOTICE
12/16/2019 NOAA is having trouble with requests that include wind gusts. I am posting graphs without wind gusts until it gets fixed.
10/9/2019 Updated the Marine Zones.
9/4/2019 Fixed the weather maps due to NOAA moving them.
7/25/2019 New feature in the Airports section gives a link to 5 minute updates for data reports.

Sunrise 5:10AMSunset 8:24PM Thursday July 2, 2020 5:45 AM EDT (09:45 UTC) Moonrise 6:01PMMoonset 2:55AM Illumination 89% Phase: Waxing Gibbous; Moon at 12 days in cycle
NOTE: Some of the data on this page has not been verified and should be used with that in mind. It may and occasionally will, be wrong. The tide reports are by xtide and are NOT FOR NAVIGATION.
Marine Forecasts
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ANZ231 Cape Cod Bay- 416 Am Edt Thu Jul 2 2020
Today..SW winds around 5 kt, becoming S this afternoon. Seas 1 foot or less. Patchy fog this morning with vsby 1 nm or less.
Tonight..SW winds 5 to 10 kt. Gusts up to 20 kt in the evening. Seas 1 foot or less.
Fri..NE winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 3 ft.
Fri night..NE winds 5 to 10 kt. Seas 2 to 3 ft. A chance of showers.
Sat..NE winds 5 to 10 kt. Seas around 2 ft.
Sat night..E winds 5 to 10 kt, becoming se after midnight. Seas 1 foot or less. Patchy fog. Vsby 1 to 3 nm.
Sun..S winds 5 to 10 kt. Seas around 2 ft. Patchy fog. A chance of showers. Vsby 1 to 3 nm.
Sun night..SW winds 5 to 10 kt. Seas around 2 ft. A chance of showers. Vsby 1 to 3 nm.
Mon..N winds 5 to 10 kt. Seas around 2 ft.
Mon night..S winds around 5 kt. Seas 1 foot or less. Patchy fog. Vsby 1 to 3 nm. 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 416 Am Edt Thu Jul 2 2020
Synopsis for massachusetts and rhode island coastal waters.. High pres builds into the area today, while a cool front sags southward late in the day. Developing low pres on the cool front moves into the southeast waters tonight, while high pres building into coastal me and nh late tonight into Fri will bring showers and building northeast winds and seas. For information on possible hazardous weather beyond the 24-36 hour forecast period, please visit www.weather.gov/boston and follow the current hazards link above the map on the left.


7 Day Forecast for Marine Location Near North Plymouth, MA
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location: 41.99, -70.68     debug


Area Discussion for - Boston, MA
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FXUS61 KBOX 020804 AFDBOX

Area Forecast Discussion National Weather Service Boston/Norton MA 404 AM EDT Thu Jul 2 2020

SYNOPSIS. As an upper-level low pulls away from Southern New England today, warmer and generally drier weather will return to Southern New England. A few thunderstorms are possible late in the day, but many should stay dry. A backdoor cold front will bring clouds, scattered showers and a few thunderstorms on Friday with the main focus across interior southern New England. Cooler than normal weather follows on Saturday, July 4th across eastern New England along with morning clouds and a few showers. Very warm and humid air returns next week. There will also be a couple of cold fronts moving through during Sunday through Wednesday, each bringing showers and scattered thunderstorms.

NEAR TERM /UNTIL 6 PM THIS EVENING/. Per the Simple Water Vapor RGB imagery, the center of the upper low which has plagued our area for most of the last few days is near the northern end of Narragansett Bay as of early this morning. This feature will finally exit stage right through today. But in the interim, a large areal coverage of persistent and locally dense fog has set in early this morning across much of central and eastern MA, northern/central RI and into parts of Windham and Tolland Counties in CT. Recently wet ground and enough radiational cooling with light winds has permitted fog to develop. Though visibilities may not truly be as low as one- quarter mile, the persistence of the fog and low visibilities which should translate to difficult travel justifies issuance of a Dense Fog Advisory which lasts through 9 AM/13z. Have also issued a fog SPS for Cape Cod, where fog has been more transient but could still hamper travel. Another area that will be watching for fog development is across the CT Valley and may need an SPS for this area as well. Fog is expected to dissipate shortly after daybreak in most areas.

After fog and stratus clears, a west-east mid-level ridge axis builds into Southern New England, leading to mostly sunny skies with still elevated dewpoints. Temperatures warming into the 80s should allow for another day of moderate convective instability to build into the afternoon. Some difference exists on the magnitude - the 00z HREF and the NAM are on the more unstable side (between 1000-1500 J/kg of CAPE) with the RAP being around 600- 900 J/kg. This should be enough to result in cumulus /towering-Cu development, but there are two potential limitations. One is a large area of dry mid-level air in model soundings that could stunt deeper convective growth. The other is a westerly non- convergent flow/lack of a large- scale lifting mechanism - outside of potential mesoscale sources like the sea- breeze or terrain. That should result in more isolated coverage of showers/storms thru mid-afternoon, if any develop at all. However by later in the day (thinking after 20z/4 PM) the NAM and to an extent the RAP show a surface trough axis which sags southward from VT/NH. Though a few CAMs including the HRRR maintain dry conditions, several CAMs (NSSL WRF, NAM-3km, and the WRF NMM/ARW windows) generate scattered thunderstorms progressing southward. CAM signals point to central MA, eastern CT into RI as an area that could see thunderstorms. SPC has a Marginal Risk for severe weather across northern/north-central New England. Given current uncertainties/limitations and lack of better agreement in the CAMs on storm development, a key to monitor today will be what transpires across NH/VT and if storms can get going. If they do and begin to approach our northern border . strongly heated low- levels with 0-3 km AGL lapse rates being roughly dry-adiabatic could lead to isolated strong storms with gusty winds, but also potentially robust outflows that could trigger more storm development. In general, I'm not thinking the coverage of storms would be anything worse than scattered, and many should stay dry.

SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/. Tonight:

Any showers or storms which developed during the day should progress southward early tonight. Should have a brief window of clearing tonight into overnight. The 00z NAM/GFS show weak surface low development on the surface trough near eastern MA tonight, a feature which sags southward towards Cape Cod and the Islands by the pre- dawn hrs. In addition, high pressure over northern ME early Friday morning ridges southward into southern coastal ME/NH. This will lead to an enhanced E/NE pressure gradient late-overnight/early Friday with developing onshore flow and lower clouds that should be closing in on eastern/northeast MA. Rather mild lows are expected given upper teens 850 mb temps and partial/mostly cloudy conditions with lows in the mid to upper 60s.

Friday:

A less than ideal close to the workweek, as NE/E onshore flow, backdoor front and related clouds and at least light showers which progress southwestward across Southern New England. Heavier showers and embedded thunderstorms may lie mainly west of Worcester and especially the CT Valley into the Berkshires. Instability looks quite weak and actually decreases as the day wears on so not expecting any strong storms, but higher PoPs/QPF are generally located to western MA/western CT. Though limited opportunity for warming in the far west, I've opted for a non-diurnal temperature trend as cooler onshore flow and overcast cloudiness advects southwestward. Will have highs in the lower 70s to near 80 occurring early in the day, then falling into the low 60s to near 70 by afternoon.

LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/.

Big Picture .

The upper flow over the holiday weekend is balanced around a broad upper ridge that extends from the southwest USA across the Plains and Great Lakes. Around the edge of this ridge, the flow moves from southwest to northeast across the Pacific Northwest, peaks over the Canadian Prairies, and then moves northwest to southeast across NY and New England. This ridge de-amplifies and becomes more zonal next week, with shortwaves moving through the flow.

Per the SPC Sounding climatology, normal 500-mb heights for early July are between 573 and 583 Dm. Values through the weekend will be roughly 578 to 582 Dm, thus roughly normal in the deep layer. An east wind in the surface layer will likely bring cooler values especially in Eastern MA/RI. Values are then forecast to rise to 582 to 586 Dm by midweek next, thus trending above normal.

Mass fields are roughly the same through Sunday, then diverge early next week. However, during this time the flow shows multiple shortwaves moving through. Such shortwaves can change their timing over successive model suites, and this is even demonstrated by the suites of the past 24 hours. Forecast confidence is moderate overall, but diminishing by midweek next.

Daily details .

Friday night and Independence Day .

High pressure over the Maritimes extends to New England, bringing an cooling east flow over land that should stabilize the airmass over this region. Leftover convection over CT and Western MA should dissipate early in the night. Marine clouds then linger through the night over the three-state-region.

The high then shifts south over Southern New England Saturday, which should allow the marine clouds to diminish during the late morning and afternoon. Both the GFS and ECMWF show a weak shortwave moving through the upper flow Saturday, and the GFS uses this to forecast showers. However the same model forecasts no lift, and just a couple of hundred of J/Kg of CAPE. PW values will be around 1.25 inches, which is on the high end of normal. Will forecast slight chance pops along the Berkshire east slopes Saturday afternoon. Mixing inland reaches to between 850 mb and 900 mb, where temps support surface max temps around 80. Mixing in the east reaches 950 mb or lower, where temps support max sfc temps from around 70 to the mid 70s. Dew points of 55 to 65 suggest similar min temps each night.

Sunday through Wednesday .

Digging shortwave from Hudsons Bay sweeps over New England Sunday, pushing a cold front across New England. This is 24-hours earlier than was projected yesterday morning, showing the flexibility of these solutions. CAPE ahead of this cold front is projected at 500- 1000 J/Kg, which could generate afternoon/early night lift for showers/thunder. PW values climb to around 1.5 inches, which is starting to be above normal. Mixing to 800 mb taps 11-12C at that level, which supports max sfc temps well into the 80s inland, with 70s on the South coast.

High pressure then builds south behind the cold front for Monday, bringing clearing skies and fair weather.

The ridge shifts east Tuesday, bringing a southerly low level flow and increasing instability. CAPE climbs to 1000-1500 J/Kg in CT and Western MA, possibly Central MA. PW values climb to 1.6 inches. The south flow expands east Wednesday, with instability also expanding east. This suggests a chance of showers/thunder in all of Srn New England Wednesday. Temps should reach the 80s, possibly around 90 Wednesday.

AVIATION /08Z THURSDAY THROUGH MONDAY/. Forecaster Confidence Levels .

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

06z TAF Update:

Overnight/Early AM: High confidence in trends, moderate on timing and location.

Flight categories to deteriorate to IFR to LIFR ceilings/visbys due to fog, stratus or both. While most of the CT Valley is VFR, most of the TAF sites here should also go sub-VFR with fog. Fog and stratus will tend to improve into the 10-12z timeframe with west flow and sunrise. Winds light/calm initially, to become light W by daybreak.

Today: High confidence.

Leftover sub-VFR stratus/fog to burn off quickly to VFR conditions. Moderately unstable conditions develop which could pop isolated SHRA/TSRA 16-18z, but somewhat better chances late in the day (20-00z) with scattered TSRA moving southward from NH/VT along a surface wind shift. Storms could become strong, though net coverage likely less than yesterday. Possible IFR visby and gusty winds if a direct hit; will indicate VCSH and monitor trends as confidence on TSRA is less than prior days.

Winds become W 3-6 kt, though sea breeze ESE/SE winds set up at BOS. Mainly SW winds 4-8 kt across Cape/ACK.

Tonight: High confidence thru about 09z, then trends moderate.

Any leftover SHRA/TSRA to weaken early tonight to VFR conditions. As weak sfc low shifts into the southeast waters overnight/pre-dawn, increased onshore/NE wind will likely lead to onshore stratus. Timing of stratus onset still isn't clear but best chance eastern MA terminals and the Cape. Light winds to become NE 4-8 kt in the interior, and around 6-10 kt with occasional gusts to 15 kt eastern coasts.

Friday: Moderate confidence.

Deterioration to MVFR-IFR with showers, possible embedded thunder at BAF-BDL and perhaps ORH. Trends in timing and any potential improvement less clear. NE/E winds continue, strongest and occasional gusts near the eastern coast.

KBOS Terminal . Moderate confidence in TAF. Offshore stratus/fog near Mass Bay could advect inland 06-10z.

KBDL Terminal . Moderate confidence in TAF.

Outlook /Friday Night through Monday/ .

Friday Night: MVFR/IFR conditions possible. Breezy. Slight chance SHRA, patchy BR.

Independence Day: Mainly VFR, with local IFR possible.

Saturday Night: Mainly VFR, with local IFR possible. Patchy BR.

Sunday: Mainly VFR, with areas MVFR possible. Chance SHRA, slight chance TSRA.

Sunday Night: Mainly VFR, with local IFR possible. Chance SHRA, slight chance TSRA, patchy BR.

Monday: VFR.

MARINE. Winds and seas remain below small-craft levels through most of tonight. Areas of low clouds and intervals of fog on the waters early this morning should clear by mid-morning. Possible isolated showers/storms late today into early tonight but confidence isn't high.

Late tonight and into Friday, a developing NE onshore flow between weak low pressure over Nantucket and ridging over coastal Maine will lead to strengthening NE winds on all waters and building seas near or just over 5' on the northeast waters. While conditions remain sub- SCA on the southern waters, have hoisted a SCA for wind gusts ~25 kt and seas building to 5' for Mass and Ipswich Bays and the Stellwagen Bank through 18z Friday. It is possible this SCA may need expansion in time into early Friday evening.

Outlook /Friday Night through Monday/ .

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

Independence Day: Winds less than 25 kt. Slight chance of rain showers.

Saturday Night: Winds less than 25 kt. Patchy fog. Areas of visibility 1 to 3 nm.

Sunday: Winds less than 25 kt. Chance of rain showers.

Sunday Night: Winds less than 25 kt. Chance of rain showers, slight chance of thunderstorms.

Monday: Winds less than 25 kt.

BOX WATCHES/WARNINGS/ADVISORIES. CT . Dense Fog Advisory until 9 AM EDT this morning for CTZ003-004. MA . Dense Fog Advisory until 9 AM EDT this morning for MAZ004>007- 012>021-026. RI . Dense Fog Advisory until 9 AM EDT this morning for RIZ001>005- 007. MARINE . Small Craft Advisory from 5 AM to 2 PM EDT Friday for ANZ250- 251.

SYNOPSIS . WTB/Loconto NEAR TERM . Loconto SHORT TERM . Loconto LONG TERM . WTB AVIATION . WTB/Loconto MARINE . WTB/Loconto


Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
44090 21 mi48 min 68°F
44013 - BOSTON 16 NM East of Boston, MA 25 mi55 min W 5.8 G 7.8 65°F 68°F3 ft1008.1 hPa (-0.4)65°F
WAXM3 - Waquoit Bay Reserve, MA 29 mi60 min Calm 68°F 1009 hPa68°F
FRVM3 - 8447386 - Fall River, MA 32 mi45 min 73°F
44018 - SE Cape Cod 30NM East of Nantucket, MA 32 mi55 min W 3.9 G 5.8 65°F 3 ft1009.3 hPa (-0.5)65°F
BHBM3 - 8443970 - Boston, MA 32 mi45 min 64°F
BZBM3 - 8447930 - Woods Hole, MA 32 mi45 min 69°F
BLTM3 - 8447387 - Borden Flats Light at Fall River, MA 33 mi45 min WNW 2.9 G 4.1
FRXM3 33 mi57 min 67°F 64°F
44029 - Buoy A0102 - Mass. Bay/Stellwagen 37 mi101 min WNW 3.9 G 3.9 63°F 4 ft1007.2 hPa
FOXR1 - 8454000 - Providence, RI 40 mi45 min WNW 2.9 G 4.1 68°F
44020 - NANTUCKET SOUND 40 mi25 min SW 7.8 G 9.7 67°F 70°F1008.6 hPa67°F
PVDR1 40 mi45 min Calm G 1
CPTR1 - 8452944 - Conimicut Light, RI 40 mi45 min 72°F
PRUR1 42 mi57 min 64°F 64°F
NAXR1 - Narragansett Bay Reserve, RI 43 mi60 min WSW 1 62°F 1010 hPa61°F
PTCR1 - 8452951 - Potter Cove, Prudence Island, RI 43 mi45 min WNW 1.9 G 4.1
CHTM3 44 mi117 min SW 1.9 G 2.9 63°F 1009 hPa
BUZM3 - Buzzards Bay, MA 45 mi45 min W 8.9 G 8.9 1010.5 hPa (-0.4)
NWPR1 - 8452660 - Newport, RI 48 mi45 min W 2.9 G 5.1 63°F
QPTR1 - 8454049 - Quonset Point, RI 48 mi45 min WSW 2.9 G 4.1 72°F

Wind History for Borden Flats Light at Fall River, MA
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Plymouth, Plymouth Municipal Airport, MA6 mi53 minN 010.00 miOvercast66°F64°F96%1009.2 hPa
Marshfield Airport, MA7 mi70 minVar 30.25 miFog66°F66°F100%1009.1 hPa
Taunton, Taunton Municipal Airport, MA19 mi53 minN 00.25 miFog66°F64°F93%1009.2 hPa
Otis Air National Guard Base, MA24 mi60 minWSW 510.00 miOvercast66°F66°F100%1009.5 hPa

Link to 5 minute data for KPYM

Wind History from PYM (wind in knots)
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Last 24hrW3W3CalmSW4W73S5E5E9NE10CalmSW4CalmSW4SW3CalmCalmCalmCalmCalmCalmCalmCalmCalm
1 day agoN5NW7N4N4N6N8NE7NE7NE8E4E5E8NE9NE4NE5NE4CalmE3CalmCalmS3CalmCalmSW3
2 days agoN3N4N6NE5N8NE8NE8NE14
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Tide / Current Tables for Plymouth, Massachusetts
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Plymouth
Click for Map
Thu -- 02:55 AM EDT     Moonset
Thu -- 03:35 AM EDT     -0.56 feet Low Tide
Thu -- 05:11 AM EDT     Sunrise
Thu -- 09:35 AM EDT     9.46 feet High Tide
Thu -- 03:46 PM EDT     0.15 feet Low Tide
Thu -- 06:01 PM EDT     Moonrise
Thu -- 08:21 PM EDT     Sunset
Thu -- 09:53 PM EDT     11.07 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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6.43.91.3-0.3-0.40.82.95.47.79.29.48.46.84.72.40.60.21.23.35.98.510.511.110.3

Tide / Current Tables for Cape Cod Canal, Massachusetts Current
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Cape Cod Canal
Click for Map
Thu -- 01:22 AM EDT     0.03 knots Slack
Thu -- 02:55 AM EDT     Moonset
Thu -- 04:31 AM EDT     4.31 knots Max Flood
Thu -- 05:12 AM EDT     Sunrise
Thu -- 07:51 AM EDT     -0.21 knots Slack
Thu -- 10:38 AM EDT     -4.43 knots Max Ebb
Thu -- 01:46 PM EDT     0.01 knots Slack
Thu -- 04:52 PM EDT     4.28 knots Max Flood
Thu -- 06:00 PM EDT     Moonrise
Thu -- 08:08 PM EDT     -0.16 knots Slack
Thu -- 08:20 PM EDT     Sunset
Thu -- 11:04 PM EDT     -4.70 knots Max Ebb
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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-3.5-1.92.43.74.24.33.82.8-1.2-3.4-4.3-4.4-3.9-2.71.53.34.14.343.21.2-3.1-4.3-4.7

Weather Map
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GEOS Local Image of    EDIT
NOTE: East coast views moved to GEOS-16. They are experimental and not well supported by NOAA so they may not be correct so be warned. This change required redoing a large amount of the GOES code. If the image you are expecting is not showing, please let me know. You may need to use the EDIT function to update your location.
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Wind Forecast for Boston, MA (5,6,7,8)
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Ground Weather Radar Station Boston, MA
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Disclaimer:
The information on this web site has not been checked for accuracy. It is for entertainment purposes only and should be independently verified before using for any other reason. There are five sources. 1) Documents and manuals from a variety of sources. These have not been checked for accuracy and in many cases have not even been read by anyone associated with L-36.com. I have no idea of they are useful or accurate, I leave that to the reader. 2) Articles others have written and submitted. If you have questions on these, please contact the author. 3) Articles that represent my personal opinions. These are intended to promote thought and for entertainment. These are not intended to be fact, they are my opinions. 4) Small programs that generate result presented on a web page. Like any computer program, these may and in some cases do have errors. Almost all of these also make simplifying assumptions so they are not totally accurate even if there are no errors. Please verify all results. 5) Weather information is from numerous of sources and is presented automatically. It is not checked for accuracy either by anyone at L-36.com or by the source which is typically the US Government. See the NOAA web site for their disclaimer. Finally, tide and current data on this site is from 2007 and 2008 data bases, which may contain even older data. Changes in harbors due to building or dredging change tides and currents and for that reason many of the locations presented are no longer supported by newer data bases. For example, there is very little tidal current data in newer data bases so current data is likely wrong to some extent. This data is NOT FOR NAVIGATION. See the XTide disclaimer for details. In addition, tide and current are influenced by storms, river flow, and other factors beyond the ability of any predictive program.