Monday, August21, 2017 L-36.com


Marine Weather and Tides
Ocean Bluff-Brant Rock, MA

Version 3.4
What's New / NOTES
6/25/2017 - NOAA is having a major issue that impact the 7 day forecast load times. Many users are reporting problems. The issue has been reported.
5/23/2017 - Worked with NOAA again to speed up the 7 day forecast load times. Thanks to them for being responsive.
5/19/2016 - There were issues with the 3 day airport observation history. I switched to another data source. Let me know if you see any issues with the data feeds.

Sunrise 5:56AMSunset 7:35PM Monday August 21, 2017 7:52 AM EDT (11:52 UTC) Moonrise 5:37AMMoonset 7:39PM Illumination 1% Phase: New Moon; Moon at 29 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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ANZ251 Massachusetts Bay And Ipswich Bay- 716 Am Edt Mon Aug 21 2017
Today..W winds around 5 kt, becoming S this afternoon. Seas 1 foot or less.
Tonight..SW winds 5 to 10 kt with gusts up to 20 kt. Seas around 2 ft.
Tue..SW winds 5 to 10 kt, becoming S 15 to 20 kt with gusts up to 25 kt in the afternoon. Seas 2 to 3 ft.
Tue night..SW winds 10 to 15 kt with gusts up to 25 kt. Seas 2 to 4 ft. Showers likely with a chance of tstms. Some tstms may produce heavy rainfall.
Wed..SW winds 5 to 10 kt. Seas 1 foot or less. Showers likely with a chance of tstms. Some tstms may produce heavy rainfall.
Wed night..W winds 5 to 10 kt. Seas 1 foot or less.
Thu..W winds 5 to 10 kt. Seas 1 foot or less.
Thu night..NW winds 5 to 10 kt. Seas 1 foot or less.
Fri..NE winds 5 to 10 kt. Seas around 2 ft.
Fri night..W winds around 5 kt. Seas 1 foot or less. Winds and seas higher in and near tstms. 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 716 Am Edt Mon Aug 21 2017
Synopsis for massachusetts and rhode island coastal waters.. High pres over the region will move offshore Tue, which will allow a cold front to cross the waters Wed. Large high pres will build E from the great lakes Thu and Fri. 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 Ocean Bluff-Brant Rock, MA
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location: 42.15, -70.62     debug


Area Discussion for - Boston, MA
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Fxus61 kbox 211057
afdbox
area forecast discussion
national weather service taunton ma
657 am edt Mon aug 21 2017

Synopsis
High pressure moves offshore today. Southwest winds bring warm
humid air Tuesday night, which will feed developing showers and
thunderstorms. The wet weather will continue into Wednesday,
until a cold front sweeps across southern new england. High
pressure brings dry weather Thursday through Sunday.

Near term until 6 pm this evening
7 am update...

patchy clouds and fog at sunrise. Much of this will dissipate as
the Sun warms the air. Observed temp were a couple of degrees
cooler than forecast, but are now moving into the warming part
of the diurnal cycle. No significant changes planned for the
forecast.

Previous discussion...

temperatures will rebound quickly this morning thanks to plenty
of sunshine. Model cross sections show enough low level
moisture to result in diurnal cumulus once again today, but
coverage should not be enough to affect viewing of the partial
solar eclipse this afternoon (unless one of those clouds ends up
in the wrong place at the wrong time!) any higher clouds will
remain thin enough to allow good viewing. Remember to wear safe
glasses in order to protect your eyes.

The only other issue today is whether or not a weak sea breeze
develops for a few hours from late morning into early afternoon,
before gradient tightens and SW flow gets underway. Forecast
soundings show deep enough mixing in boston which should prevent
sea breeze from making it onto land, although it's certainly
possible any sea breeze could stay parked over boston harbor.

Highs will top out in mid to upper 80s across much of area.

Short term 6 pm this evening through 6 pm Tuesday
Mid level short wave is expected to dampen out as it reaches sne
tonight. This will cause any convection that develops to our
west today to weaken as it reaches out area, especially given
loss of daytime heating and little overall support for
convection this far east. It's still possible that a few showers
survive the trip, especially given increase in low level
moisture, mainly in western new england and near south coast.

Cold front approaches from great lakes Tuesday, but will be far
enough to our west to keep better chances of convection outside
of sne. Models are fairly aggressive in trying to bring at least
scattered showers storms into region, especially given surface-
based CAPE in excess of 1000 j kg and plenty of low level
moisture as precipitable water values climb to nearly 2 inches.

However better large scale lift should be located closer to cold
front, so we're not convinced we'll see much in way of
showers storms until very late in day across western new
england. It's possible a few showers develop due to heating and
moist airmass in place however.

Other issue is with high temperatures. NAM keeps much more low
level moisture locked in which keeps highs in low to mid 80s,
while GFS does not and highs end up closer to 90. Persistent sw
flow certainly favors NAM and it also has support from high-res
models (nmm in particular). It may end up that south coastal
areas hang onto clouds fog for much of day, while areas farther
inland are able to break out into sunshine. Based upon model
consensus, nudged highs down slightly (mid to upper 80s).

Long term Tuesday night through Sunday
Big picture...

low pressure from central canada digs over quebec Tuesday night and
swings the trough axis across the northeast usa during the late
week. Cyclonic flow lingers over new england through next
weekend. With upper heights lowering after midweek, expect
temperatures to trend seasonably cool during the period.

Gfs and ECMWF mass and thermal fields are similar through the
period, although with small differences developing Saturday and
Sunday. Thus, forecast confidence is moderate to high.

Details...

Tuesday night and Wednesday...

upper shortwave moving up the st lawrence valley will swing a cold
front across the northeast usa. Consensus of timing would bring the
front across new york state Tuesday night and across southern new
england on Wednesday morning. Deep moisture along with pw values of
2+ inches will be acted on by favorable dynamics in the right
entrance region of the upper jet. This suggests potential for
thunderstorms with locally heavy downpours. Winds at 850 mb are
forecast at 35-40 knots and 500 mb winds around 50 knots. So there
is also a potential for a few strong wind gusts.

Thursday through Sunday...

high pressure builds in at the surface while an upper trough digs
south from quebec. The trough will carry a cold pool with cold
advection aloft on Friday. Temperatures at 500-mb will minimize at
-16c to -18c Saturday morning. Moisture fields show a moist layer
between 850 and 700 mb during this period, but dry air above and
below. This looks like a partly cloudy and dry pattern, but the
instability shows some potential for a few showers. For now we will
maintain pops at less than 15 percent.

The mixed layer reaches to between 850 and 800 mb, with temps at the
top of the layer supporting MAX sfc temps in the 70s. Dew points
will be in the 50s Thursday-Friday and 45-55 over the weekend... With
light winds allowing min temps in the 50s each night.

The light wind flow will allow sea breezes to develop each late
morning and afternoon Friday through Sunday.

Aviation 12z Monday through Friday
Forecaster confidence levels...

low - less than 30 percent.

Moderate - 30 to 60 percent.

High - greater than 60 percent.

Short term through Tuesday ...

vfr today, with W winds becoming SW this afternoon. It's
possible a weak sea breeze develops near eastern ma coast 15z-
18z, but confidence is not high enough to include a sea breeze
in the forecast.

Vfr conditions persist through midnight, but MVFR ifr ceilings
should develop overnight, especially from western new england
to south coast. Ceilings should slowly lift Tuesday toVFR,
except along south coast, cape, and islands where ifr may last
much of the day due to persistent SW flow.

Scattered thunderstorms are possible Tuesday afternoon across
interior, mainly near berkshires.

Kbos terminal... High confidence in taf. Low chance of a weak sea
breeze 15z-18z but currently expecting it to remain offshore.

Kbdl terminal... High confidence in taf.

Outlook Tuesday night through Friday ...

areas of MVFR CIGS vsbys in showers thunderstorms Tuesday night and
Wednesday morning.

OtherwiseVFR all areas, with patchy ifr CIGS vsbys in fog Wednesday
night early Thursday and Thursday night early Friday.

Marine
Forecaster confidence levels...

low - less than 30 percent.

Moderate - 30 to 60 percent.

High - greater than 60 percent.

Short term through Tuesday ... High confidence.

Sw flow gets underway today as high pressure moves offshore.

That said, gradient may weaken enough to allow for a sea breeze
to develop on eastern ma waters from late morning into early
afternoon before winds shift to S sw.

Small craft advisories are being posted from Tuesday afternoon
into Tuesday night for south coastal and outer coastal waters.

Gusts should reach 25 to perhaps 30kt, along with building seas
up to 6-7 ft offshore.

Outlook Tuesday night through Friday ...

Tuesday night...

southwest winds near 25 knots Tuesday night will maintain building
seas with heights 5 to 7 feet on the outer waters and on ri sound
and block island sound.

Wednesday through Friday...

cold front moves across the waters, turning winds from the west-
northwest. High pressure then builds in with winds diminishing to
less than 20 knots. Winds further turn from the north on Friday.

Diminishing wind will bring diminishing seas, with some leftover 5
foot seas Wednesday followed by seas 3 feet or less Thursday and
Friday.

Box watches warnings advisories
Ct... None.

Ma... None.

Ri... None.

Marine... Small craft advisory from 2 pm Tuesday to 6 am edt Wednesday
for anz231>235-237-250-254>256.

Synopsis... Wtb jwd
near term... Wtb jwd
short term... Jwd
long term... Wtb
aviation... Wtb jwd
marine... Wtb jwd


Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
44013 - BOSTON 16 NM East of Boston, MA 14 mi62 min WSW 7.8 G 9.7 67°F 68°F1 ft1021 hPa (+1.5)
44090 26 mi48 min 69°F1 ft
44029 - Buoy A0102 - Mass. Bay/Stellwagen 26 mi108 min W 7.8 G 9.7 66°F 67°F1 ft1020.1 hPa
BHBM3 - 8443970 - Boston, MA 27 mi52 min 71°F 1020.2 hPa (+0.9)
WAXM3 - Waquoit Bay Reserve, MA 40 mi67 min Calm 71°F 1022 hPa69°F
FRVM3 - 8447386 - Fall River, MA 42 mi52 min 70°F 74°F1022.3 hPa (+0.9)
FRXM3 43 mi52 min 69°F 62°F
BZBM3 - 8447930 - Woods Hole, MA 43 mi52 min 69°F 73°F1021.7 hPa (+1.2)
BLTM3 - 8447387 - Borden Flats Light at Fall River, MA 43 mi52 min Calm G 0 71°F 1020.8 hPa (+1.0)
PVDR1 48 mi52 min Calm G 1 68°F 1021.2 hPa (+0.9)62°F
FOXR1 - 8454000 - Providence, RI 48 mi52 min S 1.9 G 2.9 69°F 71°F1020.8 hPa (+0.9)
CPTR1 - 8452944 - Conimicut Light, RI 49 mi52 min WSW 1.9 G 1.9 68°F 73°F1021.4 hPa (+1.0)

Wind History for Borden Flats Light at Fall River, MA
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Marshfield Airport, MA5 mi77 minW 410.00 miFair63°F60°F94%1021.3 hPa
Plymouth, Plymouth Municipal Airport, MA18 mi60 minN 010.00 miFair63°F59°F87%1021.6 hPa
Provincetown Municipal Airport, MA24 mi56 minW 510.00 miFair67°F63°F87%1021.4 hPa

Wind History from GHG (wind in knots)
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Last 24hr4
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6W7NW7Calm6NW86NW663CalmCalmCalmW3W3W4W4W45W543
1 day ago54Calm5E5E6E8SE6E5E4CalmCalmCalmW4W3SW4W3CalmCalmW4SW4W3W4W5
2 days agoS55S11S8
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SW5SW4CalmCalmCalmCalm5
G11

Tide / Current Tables for Brant Rock, Green Harbor River, Massachusetts
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Brant Rock
Click for Map
Mon -- 05:18 AM EDT     -1.20 feet Low Tide
Mon -- 05:37 AM EDT     Moonrise
Mon -- 05:56 AM EDT     Sunrise
Mon -- 11:35 AM EDT     10.06 feet High Tide
Mon -- 02:31 PM EDT     New Moon
Mon -- 05:33 PM EDT     -0.57 feet Low Tide
Mon -- 07:33 PM EDT     Sunset
Mon -- 07:38 PM EDT     Moonset
Mon -- 11:51 PM EDT     11.13 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
10.48.663.10.3-1.1-0.80.73.15.88.49.8108.96.84.21.5-0.3-0.413.268.710.6

Tide / Current Tables for Boston Harbor, Massachusetts Current
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Boston Harbor
Click for Map
Mon -- 02:45 AM EDT     -1.43 knots Max Ebb
Mon -- 05:02 AM EDT     0.00 knots Slack
Mon -- 05:38 AM EDT     Moonrise
Mon -- 05:57 AM EDT     Sunrise
Mon -- 08:21 AM EDT     1.37 knots Max Flood
Mon -- 11:01 AM EDT     -0.00 knots Slack
Mon -- 02:31 PM EDT     New Moon
Mon -- 03:14 PM EDT     -1.34 knots Max Ebb
Mon -- 05:25 PM EDT     0.00 knots Slack
Mon -- 07:35 PM EDT     Sunset
Mon -- 07:40 PM EDT     Moonset
Mon -- 08:42 PM EDT     1.34 knots Max Flood
Mon -- 11:19 PM EDT     -0.00 knots Slack
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
-0.9-1.2-1.4-1.4-1-00.91.21.31.30.70-0.5-1-1.2-1.3-1.2-0.50.61.11.31.310.2

Weather Map and Satellite Images
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Weather Map
wmap_A
IR Satellite Image from GEOS
east_satellite

GOES Local Image of Northeast    EDIT
Geos

Wind Forecast for Boston, MA (7,2,3,4)
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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 numerious 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.