Saturday, July21, 2018 L-36.com


Marine Weather and Tides
Marblehead, MA

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7/21/2018 Trying to make page Mobile Friendly

Sunrise 5:24AMSunset 8:15PM Saturday July 21, 2018 3:30 PM EDT (19:30 UTC) Moonrise 3:01PMMoonset 1:01AM Illumination 64% Phase: Waxing Gibbous; Moon at 9 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- 308 Pm Edt Sat Jul 21 2018
.small craft advisory in effect from 10 pm edt this evening through Sunday evening...
Tonight..E winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 4 ft. A slight chance of showers this evening, then showers with a chance of tstms after midnight. Patchy fog after midnight. Some tstms may produce heavy rainfall after midnight with vsby 1 to 3 nm.
Sun..SE winds 10 to 15 kt with gusts up to 30 kt. Seas 3 to 5 ft. Patchy fog. Showers with a chance of tstms. Some tstms may produce heavy rainfall. Vsby 1 nm or less.
Sun night..SE winds 10 to 15 kt with gusts up to 20 kt. Seas 3 to 5 ft. Patchy fog. A chance of showers. Vsby 1 to 3 nm.
Mon..S winds 5 to 10 kt. Seas 2 to 4 ft. Patchy fog. A chance of showers. Vsby 1 to 3 nm.
Mon night..S winds 5 to 10 kt. Seas 2 to 4 ft.
Tue..S winds 5 to 10 kt. Seas 2 to 4 ft.
Tue night..S winds 5 to 10 kt. Seas 2 to 4 ft.
Wed..S winds 5 to 10 kt. Seas 2 to 4 ft.
Wed night..S winds 5 to 10 kt. Seas 2 to 4 ft. A chance of showers.
Thu..S winds 10 to 15 kt. Seas 2 to 4 ft. A chance of showers.
Thu night..S winds 10 to 15 kt. Seas 2 to 4 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 308 Pm Edt Sat Jul 21 2018
Synopsis for massachusetts and rhode island coastal waters.. Low pres off the mid-atlantic coast will lift north tonight and Sunday bringing a tropical airmass accompanied by showers, tstms and gusty se winds. Bermuda high pres will build west Mon through Thu keeping the tropical airmass connection over the waters. 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 Marblehead, MA
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location: 42.5, -70.85     debug


Area Discussion for - Boston, MA
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Fxus61 kbox 211346
afdbox
area forecast discussion
national weather service boston norton ma
946 am edt Sat jul 21 2018

Synopsis
High pressure over the gulf of maine provides another dry day across
new england along with comfortable humidity. Low pressure with tropical
moisture moves northward along the new jersey coast tonight with
its attending warm front approaching new england. This setup will
bringing showers and thunderstorms with torrential downpours and
gusty winds tonight into Sunday. Bermuda high pressure then builds
west toward southern new england next week bringing tropical humidity
and warm temperatures. Scattered showers and thunderstorms are possible
Monday and again Thursday with drier conditions likely Tue and wed.

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

plenty of sunshine late this morning... Except for a bit of
strato CU across northwest ma and some low clouds across the
cape islands. Given the strong july sunshine... We should see
this erode some by afternoon before it returns towards evening.

Otherwise, as previous forecaster stated one more pleasant day
with comfortable humidity levels with high pressure located
across the gulf of maine. Highs should be well up into the 70s
to the lower 80s in most locations... But probably only top out
in the lower 70s along the immediate coast with the onshore
flow.

Short term 7 pm this evening through 6 pm Sunday
Tonight into Sunday...

* highlights...

- highly anomalous synoptic setup for mid july
- tropical downpours, excessive rainfall, potential flooding
- embedded thunderstorms, possible severe weather elements
- high shear, low instability, potential for brief spin-ups
- however a measure of uncertainty, set-up bears watching
* overview...

sub-tropical low rotating round a negatively tilted cut-off closed
low across the mid-atlantic coast NW into upstate ny. An attendant
anomalous S to N low-level wind precipitable water axis, low-level
convergent beneath broad diffluence, along a lifting warm front to
the sub-tropical low. Deep moist profile with high shear, especially
0-1 km, low instability. Forecasting a slug of tropical downpour
thunderstorm activity during the early morning hours, potentially
evolving further later Sunday within the warm sector as sunshine
breaks out over S new england. Potential severe weather elements,
flooding possible, a highly anomalous situation for mid july.

However, sub-tropical low focus rotating into, as mentioned prior,
the nyc tri-state region into upstate ny. A low-level focus is still
possible into S new england, however the system is transitional as a
mid to upper level ridge builds into the region, heights rising. A
measure of uncertainty.

Split between mesoscale and global runs for the 36-48 hour period.

Difference in axis of heavy rainfall with global guidance leaning e
over the W leaning mesoscale guidance. It is perhaps an outcome of
mesoscale guidance beyond 36 hours which tends to do poorly. Not
much clarity from ensemble means probabilistics, as well as cips
analogs. Threats are there, but nailing them down remains difficult.

Break down the potential threats below.

* discussion...

flooding...

potential for tropical downpours, pockets of +1" hr rainfall rates,
yielding 1-2" total rainfall amounts, locally higher. Leaning with
an initial burst of rainfall along a convergent low-level jet, then
s to N training of tropical elements. Deep, warm column moisture,
precipitable waters 2.0-2.5", high freezing level heights, efficient
rainfall processes. Sultry environment with mid 70s dewpoints, h85
dewpoints +15c. Instability present, conditionally unstable profile,
invoking updrafts, heavy rain potential. Localized flooding is
possible.

However low confidence. Spread continues within mesoscale and global
forecast guidance. No clear signals within ensemble probabilistic
guidance and means. Greater heavy rain focus may occur towards the
delaware river valley. Meanwhile h5 ridge rising heights building
into the region during the forecast period. Can't rule out a s-n
training of tropical elements, potential flooding over new england,
but not enough clarity consistency to warrant any flood headlines.

Still a challenge to nail things down.

Winds...

combined with potential heavy rain and or severe weather elements,
forecast S gusts around 35 mph. Roughly around 2 kft agl sustained
winds 40-50 mph per forecast model consensus ahead of the sub-trop
low. GEFS SREF +5 standard deviation low-level S flow, highly
anomalous for mid july. Waters not as cold, low-level inversions not
as stout. Can't rule out locally higher gusts up as high as 45 mph
especially with potential heavy rain thunderstorms. Impacts
especially along s-coastal new england around Sunday morning
possibly continuing through the day with any breakout sunshine
within the warm sector.

Tornado waterspout...

potential for a brief spin-up. A high shear, low instability setup.

Echoes of recent concord and revere early morning tornadoes which
had a similar environment. Allegory to a landfalling tropical rain-
band associated with a cyclone, the interaction with terrain and
subsequent frictional component could potentially aid in a brief
spin-up for the early morning period with any onshore thunderstorm.

Then focus on later in the day within the warm sector. Continued low-
level jet shear within weak, subtle synoptic scale forcing as
heights rise with the enhancing atlantic ridge. Can't rule out
additional break-out midday into the afternoon activity. Low lcls
throughout with dewpoints getting into the mid 70s. SREF probs
highlighting a high probability of exceeding 0-1 km helicity over
150 m2 s2, and some indication of sigtor's over 1.

Long term Sunday night through Friday
Highlights...

* tropical humidity through at least Thursday
* greatest risk for showers t-storms Sun ngt-mon & again thu
* drier weather possible Tue and wed
Sunday night...

tropical moisture plume aligned along the eastern seaboard into new
england via deep southerly flow courtesy of anomalous 597 dam ridge
south of the maritimes and a closed low over the eastern great
lakes oh valley. Within this tropical moist conveyor belt scattered
showers and embedded thunder will continue across southern new
england. Global guidance and the NAM indicating torrential downpours
possible. This combined with ongoing convection during the day
Sunday will yield a low risk of localized flash flood threat. Wpc
recognizes this with a slight risk in their excessive rainfall
graphic. However given the time range here still enough uncertainty
to hold off on a flash flood watch but later shifts may have to
consider pending model trends. Otherwise oppressive tropical
humidity within this airmass along with warm overnight temps given
dew pts of 70-75. Breezy as well in response to lingering southerly
low level jet.

Monday...

anomalous subtropical ridge retrogrades westward into new england
with 594 dam heights into the region! These rising heights shifts
tropical moisture plume westward into ny state as the day
progresses. Thus drier weather advecting into the area from east to
west as seen in model pwat and k indices fields decreasing. Yes, not
your typical advection pattern. So risk for showers in the morning
and then a drying trend from off the ocean into eastern ma trending
westward in the afternoon. Given rising heights warming temps aloft
will not include thunder in the forecast. Very tropical feel to the
day with highs 80-85 and dew pts in the mid 70s!
Tuesday and Wednesday...

good agreement among ensembles and deterministic data sets for
subtropical ridge to continue building westward into new england
with 500 mb heights of 591-594 dam across southern new england. This
will shunt tropical moisture plume north and west of our region.

Thus Tue and Wed could turn out to be mainly dry given subsidence
and deep layer dry air aloft. However can t rule out a few tropical
isolated low top showers. Tropical airmass will remain over the
region with highs 80-85 and dew pts 70-75. Other than some patchy
morning fog possible, could be looking at two good beach days
especially across CAPE cod and nantucket, closest to the subtropical
ridge... A taste of bermuda weather.

.

Thursday...

ensembles and deterministic guidance both suggest northern stream
trough enters the great lakes. This provides cyclonic flow into new
england along with cold front approaching new england. Thus
probability of showers and t-storms on the increase. Warm and humid
conditions continue with highs 80-85 and dew pts 70-75.

Friday...

ensembles suggest FROPA sometime fri-sat time period so expecting
the tropical humidity to finally break. However still warm with
ensembles offering +16c or so at 850 mb over new england.

Aviation 14z Saturday through Wednesday
Forecaster confidence levels...

low - less than 30 percent.

Moderate - 30 to 60 percent.

High - greater than 60 percent.

Short term through Sunday ... Moderate to high confidence.

Today... MainlyVFR conditions continue through the afternoon.

The exception is mainly across the CAPE islands where some ifr
to even lifr on nantucket were impacting the region late this
morning. The strong july Sun angle may allow this to scatter out
for a time this afternoon before returning toward evening.

Always tricky with these low clouds... So will continue to
monitor trends closely.

Tonight...

lowering ifr-lifr, widespread. Ra with embedded +ra tsra towards
early morning Sunday, roughly after 6z. Gusty winds possible
25-35 kts with tsra. Both cig and vsby impacts.

Sunday...

ifr-lifr slowly lifting through the day towards MVFR to low-end
vfr. Some locations may remain ifr throughout. Morning widespread
ra with embedded +ra tsra becoming more localized along a s-n
band. Continued strong to severe weather potential with gusty
winds.

Kbos terminal...VFR conditions probably hold into late
afternoon early this evening before conditions deteriorate.

Increasing E onshore flow. Onset wet- weather towards early
morning Sunday with gusty winds, potential +ra tsra.

Kbdl terminal...VFR conditions probably hold into late
afternoon early evening before conditions deteriorate tonight.

Lowering conditions overnight Saturday into Sunday morning with
onset of widespread ra, embedded +ra tsra elements with tsra
potentially being strong to severe.

Outlook Sunday night through Wednesday ...

Sunday night: mainly MVFR, with local ifr possible. Breezy.

Chance shra, slight chance tsra, patchy br.

Monday: mainly MVFR, with areasVFR possible. Breezy. Chance
shra, patchy br.

Monday night: mainly MVFR, with local ifr possible. Chance
shra.

Tuesday through Tuesday night: mainlyVFR, with areas MVFR
possible. Chance shra.

Wednesday: mainly MVFR, with areasVFR possible. Chance shra.

Marine
Forecaster confidence levels...

low - less than 30 percent.

Moderate - 30 to 60 percent.

High - greater than 60 percent.

Short term through Sunday ... High confidence.

* highlights...

- a gale watch continues for narragansett bay and the waters
south of rhode island for tonight and Sunday.

- a small craft advisory has been issued for all other waters
for tonight and Sunday.

* discussion...

today...

increasing onshore E flow ahead of a lifting warm front. Will
see marine stratus fog envelop the waters, advect towards the
shore during the day. Low visibility possible.

Tonight through Sunday...

a storm system will be moving N along the mid-atlantic coast
and passing well W of the waters by Sunday. A strong warm front
will be moving across the waters tonight into Sunday morning.

Showers and thunderstorms with torrential rain and gusty winds
are expected late Saturday night into Sunday.

Gale force wind gusts are possible, hence the gale watch in the
waters along the ri coast. Winds are forecast to be upwards of
30 knots over all other waters late tonight and Sunday, but it
is possible that portions of these areas may need to be upgraded
to gales in subsequent forecasts. In addition, there is the
threat of a brief spin of a waterspout.

Continued marine stratus fog, the threat of low visibility.

Strong wind and wave action, there is the threat of high surf
especially along s-coastal new england, wave action building up
to 10 feet. This will also pose the threat of dangerous rip
currents.

Outlook Sunday night through Wednesday ...

Sunday night: low risk for small craft advisory winds with
gusts up to 25 kt. Rough seas up to 9 ft. Chance of rain
showers, slight chance of thunderstorms, patchy fog. Visibility
1 to 3 nm.

Monday: winds less than 25 kt. Areas of rough seas. Slight
chance of rain showers, patchy fog. Local visibility 1 to 3 nm.

Monday night: winds less than 25 kt. Seas up to 5 ft. Slight
chance of rain showers.

Tuesday through Tuesday night: winds less than 25 kt. Seas up
to 5 ft.

Wednesday: winds less than 25 kt. Seas up to 5 ft. Slight
chance of rain showers.

Box watches warnings advisories
Ct... None.

Ma... None.

Ri... None.

Marine... Small craft advisory from 2 am to 6 pm edt Sunday for
anz230>234-250-251-254-255.

Gale watch from late tonight through Sunday afternoon for
anz235>237-256.

Synopsis... Nocera sipprell
near term... Frank
short term... Sipprell
long term... Nocera sipprell
aviation... Frank nocera sipprell
marine... Nocera sipprell


Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
44013 - BOSTON 16 NM East of Boston, MA 15 mi41 min E 7.8 G 9.7 67°F 69°F1 ft1020.9 hPa (-0.8)62°F
BHBM3 - 8443970 - Boston, MA 15 mi31 min 70°F 1020.1 hPa (-1.0)
44029 - Buoy A0102 - Mass. Bay/Stellwagen 15 mi87 min SE 5.8 G 7.8 67°F 68°F1 ft1020.2 hPa
IOSN3 - Isle of Shoals, NH 34 mi31 min E 6 G 7 67°F 1020.9 hPa (-1.0)59°F
BGXN3 - Great Bay Reserve, NH 39 mi46 min ESE 5.1 76°F 60°F
44098 - Jeffrey's Ledge, NH (160) 42 mi55 min 69°F2 ft
44018 - SE Cape Cod 30NM East of Nantucket, MA 43 mi41 min E 5.8 G 7.8 66°F 2 ft1021.3 hPa (-1.2)62°F

Wind History for Providence, RI
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Beverly, Beverly Municipal Airport, MA7 mi38 minSE 1110.00 miA Few Clouds73°F62°F69%1020.4 hPa
Boston, Logan International Airport, MA13 mi97 minENE 810.00 miPartly Cloudy73°F62°F69%1021.2 hPa
Lawrence Municipal Airport, MA21 mi37 minE 910.00 miMostly Cloudy80°F59°F49%1021.2 hPa
Laurence G Hanscom Field Airport, MA23 mi95 minE 11 G 1610.00 miFair77°F55°F47%1021.8 hPa
East Milton, MA24 mi35 minE 8 mi74°F59°F60%1021.2 hPa

Wind History from BVY (wind in knots)
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Last 24hrSE14SE9SE11SE10SE5SE6SE6SE4S4S3SE3CalmCalmCalmCalmCalmCalmE4SE7SE7SE7SE7E11SE11
1 day agoSE8SE7SE7SE8S6S5S5S3SE3CalmCalmCalmW3CalmCalmCalmCalmN3CalmNE5SE8SE9SE11SE11
2 days agoNW13N9NW8N6NW4N3N4NW5N7N7N5N6N5NW4CalmNW4N5NW4N7CalmN8SE13SE11SE10

Tide / Current Tables for Marblehead, Massachusetts
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Marblehead
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Sat -- 12:39 AM EDT     0.49 feet Low Tide
Sat -- 01:00 AM EDT     Moonset
Sat -- 05:24 AM EDT     Sunrise
Sat -- 06:58 AM EDT     8.77 feet High Tide
Sat -- 12:57 PM EDT     0.69 feet Low Tide
Sat -- 03:00 PM EDT     Moonrise
Sat -- 07:25 PM EDT     9.51 feet High Tide
Sat -- 08:14 PM EDT     Sunset
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
0.80.61.32.74.76.88.38.88.375.231.30.71.32.54.36.58.49.49.38.46.74.6

Tide / Current Tables for Marblehead Channel, Massachusetts Current
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Marblehead Channel
Click for Map
Sat -- 01:00 AM EDT     Moonset
Sat -- 01:45 AM EDT     0.00 knots Slack
Sat -- 05:12 AM EDT     0.37 knots Max Flood
Sat -- 05:24 AM EDT     Sunrise
Sat -- 08:01 AM EDT     -0.00 knots Slack
Sat -- 12:09 PM EDT     -0.40 knots Max Ebb
Sat -- 02:06 PM EDT     0.00 knots Slack
Sat -- 03:00 PM EDT     Moonrise
Sat -- 05:37 PM EDT     0.39 knots Max Flood
Sat -- 08:14 PM EDT     Sunset
Sat -- 08:30 PM EDT     -0.00 knots Slack
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
-0.4-0.20.10.20.30.40.30.20-0.1-0.2-0.3-0.4-0.3-00.20.30.40.40.20.1-0.1-0.2-0.3

Weather Map and Satellite Images
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GOES Local Image of Northeast    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 (15,3,4,5)
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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.