Saturday, August17, 2019 L-36.com


Marine Weather and Tides
Plymouth, MA

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Sunrise 5:51AMSunset 7:43PM Saturday August 17, 2019 9:21 PM EDT (01:21 UTC) Moonrise 9:04PMMoonset 7:38AM Illumination 94% Phase: Waning Gibbous; Moon at 17 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- 909 Pm Edt Sat Aug 17 2019
Overnight..S winds around 5 kt. Seas 1 foot or less. Patchy fog. A slight chance of showers and tstms with vsby 1 nm or less.
Sun..SW winds around 5 kt, becoming S in the afternoon. Seas 1 foot or less. Patchy fog. Vsby 1 nm or less.
Sun night..S winds 5 to 10 kt. Seas 1 foot or less. Patchy fog. A chance of showers. Vsby 1 to 3 nm.
Mon..SW winds 5 to 10 kt, increasing to 10 to 15 kt in the afternoon. Seas around 2 ft.
Mon night..SW winds 5 to 10 kt. Seas around 2 ft.
Tue and Tue night..S winds 5 to 10 kt. Seas 1 foot or less. A chance of showers. Vsby 1 to 3 nm.
Wed through Thu..W winds 10 to 15 kt. Seas around 2 ft. A chance of showers. 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 909 Pm Edt Sat Aug 17 2019
Synopsis for massachusetts and rhode island coastal waters.. A weak ridge of high pressure across the region will result in light east to southeast into early Sunday. Most of Monday will see south to southwest winds ahead of an approaching cold front. The cold front will cross the waters Monday night to bring northwest winds for Tuesday. 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 Plymouth, MA
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location: 42, -70.54     debug


Area Discussion for - Boston, MA
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Fxus61 kbox 172241
afdbox
area forecast discussion
national weather service boston norton ma
641 pm edt Sat aug 17 2019

Synopsis
Very warm and humid conditions Sunday with an increasing risk
for some showers and thunderstorms. These conditions continue
through midweek, when a cold front will sweep through. Drier and
not as warm late next week.

Near term until 6 am Sunday morning
640 pm update...

continuing to monitor t-storms moving eastward towards sne. Numerous
thunderstorms were noted moving thru ny state and crossing into
western new england early this evening, aided by a short wave,
robust instability of 1000-2000 j kg, and effective wind shear
of 30-40 kts. As the thunderstorms move eastward with respect to
southern new england, they should diminish in intensity and
coverage, though more robust convection will pass to our north.

However, a few strong storms are possible over our far interior
zones early this evening, and possibly an isolated severe, even
as diurnal instability begins to wane, as shear in our area was
still 30-35 kts. Have upped pops to likely over far western ma,
tapering pops to the e. Cams showing diminishing coverage of
convection in our area, still expect this to be the overall
trend this evening.

At 22-23z, with higher cloud deck out of the way, visible
satellite imagery was showing the marine influenced stratus deck
starting to work its way back inland from south coastal
ri ct ma. This trend will continue this evening per previous
forecast.

4 pm discussion follows...

earlier strong t-storm with heavy rainfall has weakened over sw
ri with just isolated showers in the interior. Mlcapes around
1000 j kg with 0-6km shear 25-30 kt so can't rule out widely
scattered convection to further develop in the interior through
the afternoon given marginal instability in place. However,
best forcing is to the west assocd with the approaching
shortwave. This is where a few strong to severe storms are
possible through the afternoon.

This shortwave expected to move across northern new eng this
evening. Perhaps enough forcing for a few showers t-storms from
new york state spilling into western new eng this evening as
instability persists. And some of the hi-res cams indicate a
line of weakening convection moving through western and interior
ma before dissipating. Drier air aloft then moves in from the
north so expect mainly dry conditions late tonight.

Expect low clouds to redevelop across sne with patchy fog as
well, especially near the coast. A mild and humid night with
lows 65-70.

Short term 6 am Sunday morning through Sunday night
Sunday...

warm sector airmass across sne with boundary layer winds
turning sw. This will result in low clouds and patchy fog
burning off and giving way to at least partial sunshine. 850 mb
temps 17-18c which normally supports temps into the lower 90s,
but mixing depth may fall short of 850 mb so will go a bit
cooler with highs mid upper 80s with a few locations in ct
valley possibly reaching 90. Cooler along the coast where sea
breezes develop. Quite humid airmass with dewpoints into the
lower 70s.

Moderate instability develops in the afternoon with capes
1500-2000 j kg. While synoptic forcing is limited, enough
instability to support scattered showers t-storms in the
afternoon, mainly interior where best instability is located.

Sunday night...

expect scattered showers t-storms to linger into the evening as
decent instability persists within a well defined theta-e ridge.

Then convection diminishing overnight. Another warm and humid
night with lows upper 60s to lower 70s. Patchy low clouds and
fog may redevelop.

Long term Monday through Saturday
Guidance shows ridging over the southern usa, shifting to the SW us
during wed-fri as a hudson bay trough deepens and extends southward
into the eastern u.S. Sne remains under the influence of decent mid-
level flow, steering a series of shortwaves in our direction thru
mid-week. Exact timing is uncertain on the shortwaves passing thru,
but with increased moisture, each will have the ability to produce
some showers and possibly some thunderstorms to our area.

A cold front pushes south towards into our area Monday
night Tuesday. However there is model uncertainty on whether or not
the front pushes south of sne, at least for a period of time, or if
it stalls over our area. If the 12z NAM solution pans out, we could
get a brief reprieve on shower potential during Tuesday. However
because of the uncertainty, we will have a continued risk for
showers and thunderstorms during this timeframe. The front should
move back north of our area as a warm front during Tuesday
night Wednesday, which will keep or bring back an unstable airmass
over our area.

Then as the upper trough deepens and pushes short wave energy thru
the eastern great lakes region, a cold front will pass thru our
area. The cold frontal passage should pass thru our area during thu.

The approach and passage of this front will likely bring our
greatest chance for showers and thunderstorms for the week.

High pressure builds in from the west for fri-sat. The base of the
upper trough may lag behind, which could keep a cold pool over new
england on Friday. With much drier air in place, model QPF is
lacking, and for now will continue with this dry forecast. By
Saturday the upper trough should be to our east, with dry conditions
prevailing.

Until the cold front pushes east of our region on thu, it will be
very warm and humid. Dewpoints will remain in the mid 60s to low
70s, with relief from the humidity thu-fri. With temperatures rising
to around 90 degrees early next week, we may need heat advisories
for a time.

Aviation 00z Sunday through Thursday
Forecaster confidence levels...

low - less than 30 percent.

Moderate - 30 to 60 percent.

High - greater than 60 percent.

Short term through Sunday night ... Moderate confidence.

Tonight...

widespread ifr lifr CIGS developing this evening, originating along
the southern coastline of ct ri ma, and spreading inland during
the night. Areas of fog, especially near the coast. A few
showers t-storms moving into western ma this evening before
weakening.

Sunday...

ifr conditions improving toVFR by late morning, but slower
improvement CAPE islands. Scattered showers t-storms developing
in the afternoon, mainly interior with brief lower conditions.

Sunday night...

patchy MVFR ifr stratus and patchy fog may develop, especially
near the coast. But low confidence in areal extent of lower
cigs vsbys. Scattered evening showers t-storms possible.

Kbos terminal... Moderate confidence in taf. Expect CIGS to drop
to ifr tonight with risk of lifr cigs. Some fog but vsbys should
remain AOA 2 miles.

Kbdl terminal... Moderate confidence in taf. A period of ifr cigs
expected later tonight.

Outlook Monday through Thursday ... Moderate confidence.

Monday:VFR. Chance shra, slight chance tsra.

Monday night:VFR. Slight chance shra, isolated tsra.

Tuesday:VFR. Chance shra, slight chance tsra.

Tuesday night: mainlyVFR, with local ifr possible. Chance
shra, slight chance tsra, patchy br.

Wednesday:VFR. Chance shra, slight chance tsra.

Wednesday night: mainlyVFR, with local ifr possible. Chance
shra, slight chance tsra, patchy br.

Thursday: mainlyVFR, with local MVFR possible. Chance shra,
slight chance tsra.

Marine
Forecaster confidence levels...

low - less than 30 percent.

Moderate - 30 to 60 percent.

High - greater than 60 percent.

Short term through Sunday night ... High confidence.

Primary marine concern will be areas of fog and poor vsbys
tonight into Sun morning and and possibly another round sun
night. Generally light winds and seas through the period.

Outlook Monday through Thursday ... Moderate confidence.

Monday through Monday night: winds less than 25 kt. Areas of
seas approaching 5 ft. Slight chance of rain showers, isolated
thunderstorms.

Tuesday: winds less than 25 kt. Seas locally approaching 5 ft.

Slight chance of rain showers, isolated thunderstorms.

Tuesday night: winds less than 25 kt. Seas locally approaching
5 ft. Chance of rain showers, slight chance of thunderstorms.

Wednesday through Wednesday night: winds less than 25 kt. Areas
of seas approaching 5 ft. Chance of rain showers, slight chance
of thunderstorms.

Thursday: winds less than 25 kt. Local rough seas. Chance of
rain showers, slight chance of thunderstorms.

Box watches warnings advisories
Ct... None.

Ma... None.

Ri... None.

Marine... None.

Synopsis... Kjc nmb
near term... Kjc nmb
short term... Kjc
long term... Nmb
aviation... Kjc nmb
marine... Kjc nmb


Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
44090 16 mi52 min 70°F1 ft
44013 - BOSTON 16 NM East of Boston, MA 25 mi32 min E 12 G 14 67°F 67°F2 ft1014.9 hPa (+0.0)67°F
44018 - SE Cape Cod 30NM East of Nantucket, MA 25 mi32 min ESE 7.8 G 7.8 66°F 3 ft1016.5 hPa (+0.4)66°F
WAXM3 - Waquoit Bay Reserve, MA 29 mi97 min ENE 1.9 72°F 1016 hPa70°F
BZBM3 - 8447930 - Woods Hole, MA 34 mi58 min 72°F 71°F1015.8 hPa
44029 - Buoy A0102 - Mass. Bay/Stellwagen 36 mi78 min SE 9.7 G 12 66°F 66°F2 ft1015.9 hPa
BHBM3 - 8443970 - Boston, MA 37 mi58 min 69°F 1015.7 hPa
44020 - NANTUCKET SOUND 38 mi32 min E 7.8 G 9.7 69°F 73°F1 ft68°F
BLTM3 - 8447387 - Borden Flats Light at Fall River, MA 39 mi52 min E 6 G 7 75°F 1015.9 hPa
FRVM3 - 8447386 - Fall River, MA 39 mi58 min 76°F 77°F1016.2 hPa
FRXM3 40 mi58 min 75°F 69°F
CPTR1 - 8452944 - Conimicut Light, RI 47 mi52 min ESE 7 G 8 75°F 73°F1016 hPa
FOXR1 - 8454000 - Providence, RI 48 mi52 min W 2.9 G 8.9 76°F 73°F1015.9 hPa
NAXR1 - Narragansett Bay Reserve, RI 49 mi97 min SSE 2.9 74°F 1016 hPa71°F
PRUR1 49 mi52 min 74°F 71°F
PTCR1 - 8452951 - Potter Cove, Prudence Island, RI 49 mi52 min SE 1.9 G 2.9 74°F 1016.3 hPa

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, MA10 mi67 minSSE 310.00 miMostly Cloudy72°F69°F94%1015.9 hPa
Plymouth, Plymouth Municipal Airport, MA12 mi90 minESE 410.00 miOvercast73°F69°F87%1016.1 hPa
Provincetown Municipal Airport, MA18 mi86 minESE 410.00 miPartly Cloudy69°F66°F93%1016.5 hPa
Otis Air National Guard Base, MA24 mi97 minSE 610.00 miOvercast72°F69°F94%1015.9 hPa

Link to 5 minute data for KGHG

Wind History from GHG (wind in knots)
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Last 24hrSE44CalmCalmCalmS4Calm--CalmSE5S7SE4SE5E7SE86SE74E7E6SE8E5SE4SE3
1 day agoCalmCalmCalmCalm--CalmCalmCalmCalmCalmCalmNE7NE6--NE6E7NE7E7E10E10E5
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2 days agoCalmCalmCalmCalmCalm444CalmCalmNE4NE4355
G10
5E6E8NE65E6----Calm

Tide / Current Tables for Gurnet Point, Massachusetts
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Gurnet Point
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Sat -- 01:03 AM EDT     9.84 feet High Tide
Sat -- 05:52 AM EDT     Sunrise
Sat -- 07:24 AM EDT     0.20 feet Low Tide
Sat -- 07:38 AM EDT     Moonset
Sat -- 01:32 PM EDT     9.05 feet High Tide
Sat -- 07:34 PM EDT     0.78 feet Low Tide
Sat -- 07:40 PM EDT     Sunset
Sat -- 09:04 PM EDT     Moonrise
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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9.19.89.4863.71.60.30.41.73.45.67.68.98.986.44.42.410.92.13.85.9

Tide / Current Tables for Cape Cod Canal, Massachusetts Current
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Cape Cod Canal
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Sat -- 02:11 AM EDT     -4.55 knots Max Ebb
Sat -- 05:24 AM EDT     0.02 knots Slack
Sat -- 05:52 AM EDT     Sunrise
Sat -- 07:39 AM EDT     Moonset
Sat -- 08:30 AM EDT     4.27 knots Max Flood
Sat -- 11:53 AM EDT     -0.03 knots Slack
Sat -- 02:35 PM EDT     -4.26 knots Max Ebb
Sat -- 05:38 PM EDT     0.19 knots Slack
Sat -- 07:39 PM EDT     Sunset
Sat -- 08:37 PM EDT     4.06 knots Max Flood
Sat -- 09:04 PM EDT     Moonrise
Sat -- 11:53 PM EDT     -0.17 knots Slack
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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-2.7-4-4.5-4.3-3.6-22.43.74.24.23.82.9-1-3.3-4.1-4.2-3.6-2.41.83.3443.62.7

Weather Map and Satellite Images
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GOES 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 (21,6,7,8)
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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 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.