Sunday, February17, 2019 L-36.com


Marine Weather and Tides
Mashpee Neck, MA

Version 3.4
What's New / NOTES
10/6/2018 Colors of tide XTide graphs changed to emphasize that they were upgraded. See next note. Comments welcome.
10/4/2018 I have fixed XTide and updated the harmonic files. There were some name changes so you might have to click EDIT to find the new station name.

Sunrise 6:32AMSunset 5:17PM Sunday February 17, 2019 8:39 PM EST (01:39 UTC) Moonrise 3:58PMMoonset 6:07AM Illumination 98% Phase: Waxing Gibbous; Moon at 13 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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ANZ232 Nantucket Sound- 716 Pm Est Sun Feb 17 2019
.small craft advisory in effect late Monday night...
Tonight..SE winds 5 to 10 kt. Gusts up to 20 kt after midnight. Seas around 2 ft. A slight chance of snow this evening, then snow after midnight with vsby 1 nm or less.
Mon..E winds 10 to 15 kt, becoming N 5 to 10 kt in the afternoon. Gusts up to 20 kt. Seas 2 to 3 ft. Snow and rain. Vsby 1 nm or less.
Mon night..N winds 10 to 15 kt, becoming nw 15 to 20 kt after midnight. Gusts up to 25 kt. Seas 2 to 4 ft. A chance of snow. Vsby 1 to 3 nm.
Tue..NW winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 4 ft.
Tue night..NW winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 3 ft.
Wed..NE winds 5 to 10 kt. Gusts up to 20 kt in the morning. Seas around 2 ft.
Wed night..SE winds 5 to 10 kt, increasing to 10 to 15 kt with gusts up to 20 kt after midnight. Seas around 2 ft. Snow and sleet with rain likely. Vsby 1 to 3 nm.
Thu..SW winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 4 ft. Rain likely.
Thu night..NW winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 4 ft.
Fri..NW winds 5 to 10 kt. Seas 2 to 3 ft.
Fri night..W winds 5 to 10 kt. Seas 1 foot or less. 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 Pm Est Sun Feb 17 2019
Synopsis for massachusetts and rhode island coastal waters.. A low pressure system will pass se of nantucket Mon. High pres builds in from the W on Tue and Wed. Low pres approaches the waters from the sw Wed night, then passes just S of the waters on Thu. 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 Mashpee Neck, MA
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location: 41.61, -70.44     debug


Area Discussion for - Boston, MA
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Fxus61 kbox 180003
afdbox
area forecast discussion
national weather service boston norton ma
703 pm est Sun feb 17 2019

Synopsis
Accumulating snow overspreads the region late this evening and
overnight from west to east and continues into Monday, in
association with a low pressure tracking south of new england.

Large high pressure will bring dry but cold conditions Monday
night into early Wednesday. Snow will push across the region
late Wednesday into Wednesday evening as low pressure approaches,
then will become a wintry mix overnight before changing to rain
Thursday morning. The low will head to the gulf of maine
Thursday night. Dry conditions should return Friday into early
Saturday.

Near term until 10 pm this evening
645 pm update...

patchy mid and high clouds continue to push across the region
as seen on latest goes-east rgb nighttime microphysics composite
satellite imagery, while thin enough to see somewhat lower
clouds around 5-6kft as seen on latest surface obs across the
nyc area, approaching from ny state into central and W mass
into N ct.

Noting some thin bands of precip moving across western new
england and starting to fill in. However, not reaching the
ground with t TD spreads remain at about 15-20 degrees, highest
away from the S coast. Beginning to see dewpoints rise to the
upper teens to around 20 from kwst-ksfz-kghg to the S coast on
the 23z observations, and will continue to rise through the
night as light S winds back to E overnight.

Closest precip reaching the ground was across central pa into w
ny state, but should start to fill in over the next few hours
though precip should be light as rather wide t TD spreads
remain there as well.

Appears that onset of precip across the region is pretty much on
track from previous forecast. Have updated near term t TD winds,
etc., but kept previous pop forecast pretty much intact. Expect
temps to fall back through the 20s, possibly the upper teens
along the E slopes of the berkshires and around 30 along the
immediate S coast overnight.

Previous discussion...

dry weather prevails through about 9 or 10 pm this evening, but we
will see a significant increase in mid high level cloudiness ahead
of the approaching low pressure system. Temperatures will fall back
to the middle 20s to the lower 30s over this time.

Short term 10 pm this evening through 6 pm Monday
Highlights...

* snow develops between 10 pm and 2 am from southwest to northeast
* heaviest snow occurs through 9 am near and ESP south of pike
* snow continues Mon afternoon with focus across central eastern ma
1) overview and impacts:
approaching shortwave will increase the forcing for ascent and allow
snow to overspread the region roughly between 10 pm and 2 am Monday
morning. The heaviest snow is expected near and especially south of
the ma turnpike overnight. This is where the best forcing resides
and the guidance indicates a few hours of omega exceeding 20 units
in the snow growth region. There also is a -epv signature present
along with 700 mb lapse rates on the order of 6-7 c km. This is
supportive for a window of 1 to perhaps 2 inch per hour snowfall
rates. While this is relatively a short window, it looks to impact
ri and SE ma during the morning commute (albeit less traffic than
usual given the holiday). Ptype should mainly be snow, but enough
mid level warmth may invade the immediate south coast and
particularly the CAPE islands for a change to sleet rain towards 12z
Monday.

The first phase of the storm should come to an end by mid morning
Monday. However, there is a second portion of this event we need to
discuss. An inverted trough feature along with moist low level
onshore flow will allow for periods of generally lighter snowfall to
linger into the afternoon. In fact, the area needed for ice
nucleation dries out across portions of western ma northern ct
for a time. This may result in some freezing drizzle too.

While lighter snowfall will be the rule with the second portion of
the storm, we will need to watch central and eastern ma for locally
heavier bands. Moist onshore flow may result in some enhancement of
the snow along the east slopes of the worcester hills and perhaps
even the berks. Along the eastern ma coast, the land sea interface
may result in ocean enhancement. A look at the model cross sections
reveals saturated soundings in the optimal snow growth region. So
there might be a few bands of moderate to perhaps even briefly heavy
snow later in the morning into the late afternoon in this region.

Outside of these bands of more significant snow across central and
eastern ma, roads may be manageable given lighter snowfall rates and
marginal temperatures. Light snow showers may linger into the the
early evening hours, but any accumulations after 7 or 8 pm should be
less than an inch.

2) headlines and snow accumulations:
based on the latest data feel a widespread 3 to 6 inches of snow is
in store for much of the region. Guidance also points to a swath of
potentially 4 to 7 inch amounts in the pvd-tan-pym-ewb corridor.

Will go ahead and upgrade this region to a marginal winter
storm warning. We also will have to watch the CAPE and south
coasts of ma and ri, but more marginal temperatures and the
potential for a period of sleet rain, did not feel confident
enough to go with a warning. The rest of our county warning area
will be under a winter weather advisory. There is a low risk
though that marginal warning criteria is realized along the east
slopes of the berks orh hills with better ratios and perhaps
even boston itself with the inverted trough. Again though, just
was not confident enough in this region.

The bottom line is a moderate snow event is in the cards for the
region. Biggest impact will the morning commute near and
especially south of the ma turnpike. Also, the afternoon commute
may be an issue from the worcester hills and onto the eastern
ma coast from the inverted trough.

Long term Monday night through Sunday
* dry and cold conditions Monday night into Wednesday morning
* a chance for snow Wednesday afternoon evening, likely
changing to a wintry mix overnight then to rain Thursday
before tapering off
* another round of dry weather follows Friday into early
Saturday
* potential for more mixed precipitation Sat afternoon into
Sunday
overview...

high amplitude mid level trough remains across the western u.S.

Early in this forecast period, with general w-sw steering flow
extending from the base of this trough across the mid
mississippi and ohio valleys into the northeast through most of
this week. Some height amplification possible around late Wed or
thu as subtropical ridge off the florida coast into the sw
atlc. This may occur close to the same time as the approach of
developing low pressure out of the mississippi valley toward new
england. May see a wintry mix of precip Wed night before
eventually changing to rain thu.

May see another dry spell late this week into next weekend.

Models beginning to signal deamplification of the western
trough Thu night or fri, but rather high uncertainty with the
timing and ultimate movement of leftover troughing late Sat or
next sun.

Details...

Monday night into Wednesday morning...

last of light snow from exiting low pres will linger mon
evening across E coastal areas. Should taper off across the
outer CAPE and nantucket by around 06z. Cold air works back
across the region on n-nw winds ahead of sprawling high pres
across the plains into the western great lakes. May see wind
gusts up to around 20-25 kt or so along the immediate E coast as
well as CAPE cod and the islands.

H85 temps will drop by Tue morning, and continue to fall to -11c
to -14c by Tue evening! So, expect overnight lows both Mon and
tue nights to bottom out at around 5 degrees or so below seasonal
normals. Readings will fall to the single digits across the
higher inland terrain and mainly the teens elsewhere, though may
be a bit milder (about 20 to 25) along the immediate S coast
and islands.

The gusty winds will diminish on Tuesday as the center of the
large high approaches from the w, so expect light NW or calm
winds by Tue night.

May start to see mid and high clouds approach late Tue night
into Wed morning ahead of next approaching system.

Wednesday afternoon through Thursday...

the next southern stream system will work NE out of the
mississippi valley to the great lakes. As with the last few
systems, may see a secondary low develop as it approaches the
region Wed night into Thu morning. With some model solution
spread with each model's handling of the secondary low track,
still rather uncertain how quickly the precip will move in then,
as milder air works in aloft, when the precip mixes with
pl fzra overnight Wed night, then eventually all rain during thu
before tapering off as the low exits Thu afternoon. Current
forecast suggests that highs on Thu could reach the upper 30s to
mid 40s.

May see some gusty e-se winds around Thu morning along east
coastal areas, especially CAPE cod and the islands, which may
combine with the high astronomical tides to possibly produce
some minor coastal flooding around midday thu. Check for
details under the tides section below.

Friday through Sunday...

coastal low and associated mid level trough from Thu moves east
of new england. Expect a dry NW flow aloft and seasonable temps
fri into Sat as high pres moves across.

The next system in the fast mid level steering flow may
approach late Saturday through most of Sunday. Potential for
more mixed precipitation Saturday night into early Sunday, but
rather high uncertainty with wide model solution spread.

Aviation 00z Monday through Friday
Forecaster confidence levels...

low - less than 30 percent.

Moderate - 30 to 60 percent.

High - greater than 60 percent.

Short term through Monday ... High confidence.

Tonight and Monday... MainlyVFR early this evening.

Snow overspreads the region from southwest to northeast between
03z and 07z. This will result ifr to lifr conditions developing
overnight and persisting through Monday afternoon. Heaviest
snow occurs near and especially south of the ma turnpike through
about 13z or 14z Monday, where lifr conditions will be most
prevalent.

Generally lighter snows linger later Monday morning into the
afternoon and there may even be pockets of freezing drizzle in
western ma northern ct. Despite the overall diminishing snow
intensity, localized bands of moderate to even briefly heavier
snow will remain possible across central and eastern ma into mon
afternoon. Ptype should be all snow except for the immediate
south coast and especially the CAPE islands, where a change to
sleet rain may occur for a time Monday morning. Total snow
accumulations of 3 to 6 inches are anticipated for much of the
region.

Kbos terminal... High confidence in taf.

Kbdl terminal... High confidence in taf.

Outlook Monday night through Friday ...

Monday night: mainlyVFR, with local MVFR possible. Breezy.

Tuesday through Tuesday night:VFR. Breezy.

Wednesday: mainlyVFR, with local ifr possible. Chance sn.

Wednesday night: mainly ifr, with areas MVFR possible. Breezy.

Sn likely, fzra likely, pl likely.

Thursday: mainly MVFR, with areasVFR possible. Breezy. Chance
ra, chance fzra.

Thursday night through Friday:VFR. Breezy.

Marine
Forecaster confidence levels...

low - less than 30 percent.

Moderate - 30 to 60 percent.

High - greater than 60 percent.

Short term through Monday ... High confidence.

Tonight and Monday... High confidence.

Generally light winds and flat seas this evening. Small craft
seas up to 5 feet and northeast wind gusts up to 25 knots
develop across the southern waters near daybreak Monday and
continue into the afternoon. A few gusts approaching 25 knots
are possible Monday across some of the southern sounds and bays,
but felt it was to marginal for headlines at this point.

Periods of rain, sleet, and snow overnight into Monday will
reduce vsbys at time for mariners.

Outlook Monday night through Friday ...

Monday night: low risk for small craft advisory winds with
gusts up to 25 kt. Seas up to 5 ft. Chance of snow, chance of
freezing spray.

Tuesday: winds less than 25 kt. Local rough seas.

Tuesday night: low risk for small craft advisory winds with
gusts up to 25 kt. Areas of seas approaching 5 ft.

Wednesday: winds less than 25 kt. Seas locally approaching
5 ft. Slight chance of snow. Local visibility 1 to 3 nm.

Wednesday night: winds less than 25 kt. Seas locally
approaching 5 ft. Snow likely, rain likely, sleet likely,
freezing rain likely. Visibility 1 to 3 nm.

Thursday: low risk for small craft advisory winds with gusts up
to 25 kt. Seas up to 5 ft. Rain likely, freezing rain likely.

Thursday night: winds less than 25 kt. Local rough seas.

Friday: winds less than 25 kt. Areas of seas approaching 5 ft.

Tides coastal flooding
Highest astronomical tides of 2019 are expected Wed and thu,
with forecasted tide heights up to 12 foot or greater in boston
harbor around midday both days. Current forecast suggests
offshore winds on Wed (nw), but there could be a period of
onshore winds (e-se) which will depend upon how low pressure
tracks across the region Thu morning with the incoming tide.

It won't take much to produce minor coastal flooding along the
eastern massachusetts coastline. At this point, it looks like
the greatest threat for minor coastal flooding may occur with
the Thursday midday tide, but Wednesday's tide should also be
monitored.

Box watches warnings advisories
Ct... Winter weather advisory from 10 pm this evening to 4 pm est
Monday for ctz002>004.

Ma... Winter weather advisory from 11 pm this evening to 4 pm est
Monday for maz022>024.

Winter storm warning from 11 pm this evening to 4 pm est
Monday for maz017>021.

Winter weather advisory from midnight tonight to 4 pm est
Monday for maz002>008-010-013>016-026.

Winter weather advisory from 10 pm this evening to 4 pm est
Monday for maz009-011-012.

Ri... Winter weather advisory from 11 pm this evening to 4 pm est
Monday for riz006>008.

Winter storm warning from 11 pm this evening to 4 pm est
Monday for riz001>005.

Marine... Small craft advisory from 1 am to 5 am est Tuesday for anz232.

Small craft advisory from midnight Monday night to 5 am est
Tuesday for anz233-234.

Small craft advisory from 10 pm Monday to 6 am est Tuesday for
anz231-251.

Small craft advisory from 11 pm Monday to 6 am est Tuesday for
anz235-237.

Small craft advisory from 3 pm Monday to 6 am est Tuesday for
anz250.

Small craft advisory from 6 am Monday to 6 am est Tuesday for
anz254>256.

Synopsis... Frank evt
near term... Frank evt
short term... Frank
long term... Evt
aviation... Frank evt
marine... Frank evt
tides coastal flooding... Staff


Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
WAXM3 - Waquoit Bay Reserve, MA 5 mi114 min Calm 30°F 1019 hPa18°F
44020 - NANTUCKET SOUND 12 mi49 min SW 3.9 G 5.8 32°F 35°F1018.3 hPa19°F
BZBM3 - 8447930 - Woods Hole, MA 14 mi51 min 32°F 36°F1017.8 hPa
44090 17 mi39 min 37°F
NTKM3 - 8449130 - Nantucket Island, MA 29 mi51 min ESE 1 G 1 30°F 38°F1018.4 hPa
BUZM3 - Buzzards Bay, MA 35 mi39 min SW 5.1 G 6 33°F 1018.4 hPa (+0.0)
BLTM3 - 8447387 - Borden Flats Light at Fall River, MA 39 mi51 min SSW 5.1 G 6 33°F 1017.8 hPa
FRVM3 - 8447386 - Fall River, MA 39 mi51 min 32°F 43°F
FRXM3 40 mi51 min 33°F 17°F
44018 - SE Cape Cod 30NM East of Nantucket, MA 44 mi49 min SE 1.9 G 5.8 30°F 2 ft1018.5 hPa (+0.0)15°F
NAXR1 - Narragansett Bay Reserve, RI 48 mi114 min SW 6 32°F 1019 hPa17°F
NWPR1 - 8452660 - Newport, RI 48 mi57 min SW 6 G 8 33°F 37°F1017.8 hPa
PTCR1 - 8452951 - Potter Cove, Prudence Island, RI 48 mi57 min SW 4.1 G 6 32°F 1017.7 hPa
CPTR1 - 8452944 - Conimicut Light, RI 49 mi51 min SSW 11 G 11 32°F 39°F1018 hPa

Wind History for Nantucket Island, MA
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Otis Air National Guard Base, MA6 mi44 minESE 410.00 miMostly Cloudy25°F17°F74%1017.9 hPa
Hyannis, Barnstable Municipal-Boardman Airport, MA10 mi43 minN 010.00 miPartly Cloudy28°F18°F66%1017.9 hPa
Marthas Vineyard Airport, MA17 mi46 minN 010.00 miFair23°F14°F68%1017.9 hPa

Wind History from FMH (wind in knots)
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Last 24hrNW3NW6NW5NW6NW4NW4NW6NW4N7NW5CalmNW763NE85NE7CalmSW8S6S3N4CalmCalm
1 day agoSW25
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2 days agoCalmCalmCalmCalmCalmSE6SE6SE8SE10SE15SE15
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Tide / Current Tables for Cotuit Highlands, Nantucket Sound, Massachusetts
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Cotuit Highlands
Click for Map
Sun -- 03:17 AM EST     0.08 feet Low Tide
Sun -- 05:06 AM EST     Moonset
Sun -- 06:34 AM EST     Sunrise
Sun -- 10:01 AM EST     2.87 feet High Tide
Sun -- 02:58 PM EST     Moonrise
Sun -- 04:00 PM EST     -0.25 feet Low Tide
Sun -- 05:17 PM EST     Sunset
Sun -- 10:43 PM EST     2.54 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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1.610.50.10.20.61.11.72.32.72.92.72.11.40.70-0.3-0.10.40.91.52.12.52.5

Tide / Current Tables for Cape Cod Canal, Massachusetts Current
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Cape Cod Canal
Click for Map
Sun -- 12:52 AM EST     0.03 knots Slack
Sun -- 03:52 AM EST     4.03 knots Max Flood
Sun -- 05:07 AM EST     Moonset
Sun -- 06:35 AM EST     Sunrise
Sun -- 07:09 AM EST     -0.12 knots Slack
Sun -- 10:12 AM EST     -4.63 knots Max Ebb
Sun -- 01:22 PM EST     0.02 knots Slack
Sun -- 02:58 PM EST     Moonrise
Sun -- 04:32 PM EST     4.45 knots Max Flood
Sun -- 05:17 PM EST     Sunset
Sun -- 07:59 PM EST     -0.21 knots Slack
Sun -- 10:45 PM EST     -4.45 knots Max Ebb
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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-2.7133.843.731.2-2.8-4.1-4.6-4.4-3.6-1.92.53.84.44.443.1-0.2-3.2-4.2-4.4

Weather Map and Satellite Images
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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 (20,4,5,8)
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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.