Tuesday, October22, 2019 L-36.com


Marine Weather and Tides
Nantucket, MA

Version 3.4
NOTICE
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.
6/2/2019. Many thanks to a user for reporting an error on one of the Edit pages. The switch to PHP 7.2 caused many pages that previously worked to quit working. I fixed many but I still depend on users to report ones I missed. Please report errors HERE or send an email to me at L-36.com. Allen

Sunrise 6:59AMSunset 5:51PM Tuesday October 22, 2019 8:04 PM EDT (00:04 UTC) Moonrise 12:01AMMoonset 3:01PM Illumination 31% Phase: Waning Crescent; Moon at 24 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
    EDIT      (on/off)   Help
ANZ255 Coastal Waters Extending Out To 25 Nm South Of Marthas Vineyard And Nantucket- 716 Pm Edt Tue Oct 22 2019
.small craft advisory in effect through late Wednesday night...
Tonight..E winds 15 to 20 kt, becoming se 10 to 15 kt after midnight. Gusts up to 25 kt. Seas around 6 ft. Areas of fog. A chance of showers. Vsby 1 nm or less.
Wed..SW winds 15 to 20 kt, becoming W in the afternoon. Gusts up to 25 kt. Seas around 6 ft. Areas of fog in the morning, then patchy fog in the afternoon. A chance of showers in the morning. Vsby 1 nm or less, increasing to 1 to 3 nm in the afternoon.
Wed night..W winds 10 to 15 kt with gusts up to 25 kt, becoming nw 5 to 10 kt after midnight. Seas 5 to 6 ft.
Thu..W winds 5 to 10 kt. Seas 3 to 4 ft.
Thu night..W winds 5 to 10 kt. Seas around 3 ft.
Fri..NW winds around 5 kt, becoming sw in the afternoon. Seas 2 to 3 ft.
Fri night..SW winds 5 to 10 kt, becoming nw after midnight. Seas around 2 ft. A chance of showers.
Sat..NW winds 5 to 10 kt. Seas around 2 ft. A chance of showers in the morning.
Sat night..N winds 10 to 15 kt. Gusts up to 20 kt after midnight. Seas around 3 ft, building to 5 ft after midnight. A chance of showers after midnight.
Sun..E winds 10 to 15 kt with gusts up to 25 kt. Seas 8 to 9 ft. A chance of showers.
Sun night..NE winds 10 to 15 kt with gusts up to 20 kt. Seas around 9 ft. A chance of showers. 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 Edt Tue Oct 22 2019
Synopsis for massachusetts and rhode island coastal waters.. A cold front will pass through tonight into Wednesday, bringing S winds along with a chance of rain. High pressure and dry weather follow for the rest of this week. 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 Nantucket, MA
   Hourly   EDIT   Help
location: 41.27, -70.06     debug


Area Discussion for - Boston, MA
      (on/off)   Help   NOTE: mouseover dotted underlined text for definition
Fxus61 kbox 222301
afdbox
area forecast discussion
national weather service boston norton ma
701 pm edt Tue oct 22 2019

Synopsis
A cold front will bring a widespread showers tonight. The front
then moves off the coast Wednesday morning followed by dry and
mild conditions. Dry and seasonable conditions continue Thursday
and Friday with a gusty southwest wind Thursday. A cold front
sweeps through with a few showers Friday night. High pressure
brings dry seasonably cool temperatures Saturday. Another cold
front brings a few showers Sunday. High pressure returns with
dry weather Monday.

Near term until 6 am Wednesday morning
7 pm update...

light rain showers has moved into parts of ct-ri-se mass along
with areas of fog and low clouds. Heavier rain is found to our
southwest over eastern pa and is moving northeast toward new
england. Expect the current light rain showers for the early
night, with heavier bursts of rain moving up from the southwest,
reaching northern ct by 10 pm and northern ma by midnight.

Duration of the showers, based on the width of the shower band,
should be about 4 hours.

A few adjustments made based on 6 pm observations. Otherwise,
the forecast continues as is.

Previous discussion...

patchy light rain or drizzle will develop through early
evening, but steadier rainfall will hold off until tonight.

Area of widespread showers lifting NE from pa ahead of mid
level trough which approaches new eng tonight. Favorable upper
jet dynamics and deepening moisture plume will result in these
showers overspreading sne later this evening through the
overnight period. Models indicate a wave developing on the
front and tracking across the interior which will enhance low
level convergence to support some heavier rain elements, but
best forcing will remain to the north of the low track across
northern new eng, with a particular focus across maine as modest
low level jet develops in the gulf of maine. A secondary low
level jet moving up from the south with some elevated
instability may result in some convective showers and isolated
thunder across SE new eng late tonight and toward daybreak.

Rainfall will average 0.25-0.75" across sne with localized
amounts up to an inch.

Mild night tonight ahead of the cold front, with temperatures
remaining in the 50s but rising into the 60s across ri and SE ma
late tonight with dewpoints pushing 60 toward daybreak just
ahead of the front. Areas of fog likely.

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

cold front will be moving off the coast in the morning. Showers
lingering early, especially eastern new eng before moving
offshore by mid morning, followed by increasing sunshine from
west to east. Given mild start to the day, highs should reach
mid upper 60s, but cooler higher terrain. Gusty post-frontal
west winds develop, occasionally gusting to 25 mph.

Wednesday night...

high pressure builds south of new eng. Clear skies and
diminishing wind will allow low temps to drop into the upper
30s to low mid 40s across the region.

Long term Thursday through Tuesday
Big picture...

hudson's bay upper low was maintaining a broad trough across the usa
with upper highs over the western atlantic and eastern pacific.

Southwest upper flow over the northeast usa through the period.

Shortwaves in this flow are projected to cross our area Friday
night, Sunday, and possibly Tuesday, although exact timing becomes
less certain later in the forecast period.

The GFS continues to be a fast outlier compared with the other large-
scale guidance. Upper patterns start losing agreement Thursday... But
if the GFS is removed from consideration then the agreement holds
through the weekend. Forecast confidence starts moderate and
diminishes to low Sunday night.

Daily concerns...

Thursday...

shortwave in the upper flow moves northeast into eastern canada. The
supporting 125-kt upper jet will be near the canadian border, with
lift-supporting jet dynamics over northern new england and canada.

Expect dry weather here in southern new england. Mixing reaches to
925 mb, with southwest winds 20-25 kt in the mixed layer. Expect
gusty winds to these speeds Thursday afternoon.

Temperatures at 925 mb will be 10-12c, so expect MAX sfc temps in
the low to mid 60s. Dew points in the 40s should allow for min temps
in the 40s to low 50s Thursday night.

Friday-Saturday...

next shortwave in the southwest flow sweeps through on Friday night,
driven by a 150-kt upper jet. The 12z ECMWF drives the jet over
southern new england, while the GFS moves it over northern new
england. As noted above, the GFS is more of an outlier... Although
this is trending less with time. So we favored the ECMWF placement,
which is closer to consensus but with limited confidence. This
brings a period of showers to the region, concentrated on late
Friday early Friday night.

High pressure then builds in for Friday night and Saturday. Expect
dry weather and cooler temperatures. Temps in the mixed layer will
be equiv to -2c to -4c, so MAX sfc temps should be in the 50s.

Clouds move back in Saturday night ahead of the next weather system
and possibly a few showers in the south. But timing of the system
and its clouds remains low confidence.

Sunday through Tuesday...

exact timing of shortwaves 5 to 7 days out can be quite difficult,
and today's model suite is no exception. With the differences shown
by the various long-range guidance, that confidence is even less.

There is agreement on one or two shortwaves moving through, and so
we will show a chance of showers Sunday and, with less confidence,
Tuesday.

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

low - less than 30 percent.

Moderate - 30 to 60 percent.

High - greater than 60 percent.

Short term through Wednesday night ...

tonight... High confidence. Widespread ifr lifr with a band of
rain showers moving southwest to northeast during the night.

Low prob of an isolated t-storm across SE new eng 09-12z. Se
gusts 20-25 kt over CAPE islands.

Wednesday... High confidence.

Leftover MVFR ifr improving toVFR from west to east 13-16z.

Showers in eastern new eng exiting 12-14z. W gusts to 20 kt
developing.

Wednesday night... High confidence.VFR.

Kbos terminal... High confidence in overall taf. Lower confidence
in specific details.

Kbdl terminal... High confidence in overall taf. Lower confidence
in specific details.

Outlook Thursday through Sunday ... Moderate confidence to
Saturday, then low confidence.

Thursday:VFR. Breezy.

Thursday night:VFR.

Friday:VFR. Slight chance shra.

Friday night:VFR. Chance shra.

Saturday:VFR. Slight chance shra.

Saturday night: mainlyVFR, with local ifr possible. Breezy.

Sunday: mainlyVFR, with areas ifr possible. Breezy. Slight
chance shra.

Marine
Forecaster confidence levels...

low - less than 30 percent.

Moderate - 30 to 60 percent.

High - greater than 60 percent.

Short term through Wednesday night ... High confidence.

Developing low level jet will bring a period of SE gusts to
25-30 kt over NE ma waters tonight with seas building to 8-10
ft before jet lifts into the gulf of maine. Winds turn west
behind the cold front Wed with occasional gusts to 25 kt,
especially over south coastal waters. Winds and seas gradually
diminish Wed night.

Outlook Thursday through Sunday ... Moderate confidence to
Saturday, then low confidence.

Thursday through Thursday night: winds less than 25 kt. Areas
of seas approaching 5 ft.

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

Slight chance of rain showers.

Friday night: winds less than 25 kt. Chance of rain showers.

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

Slight chance of rain showers.

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

Sunday: low risk for small craft advisory winds with gusts up
to 25 kt. Areas of seas approaching 5 ft. Slight chance of rain
showers.

Box watches warnings advisories
Ct... None.

Ma... None.

Ri... None.

Marine... Small craft advisory until 4 am edt Wednesday for anz231-232.

Small craft advisory until 6 pm edt Wednesday for anz235-237.

Small craft advisory until 6 am edt Thursday for anz250-254.

Small craft advisory until 2 am edt Thursday for anz251-255-
256.

Synopsis... Wtb kjc
near term... Wtb kjc
short term... Kjc
long term... Wtb
aviation... Wtb kjc
marine... Wtb kjc


Weather Reporting Stations
   EDIT       (on/off)   Help   NOTE: Click on distance to see the station location on a map
Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
NTKM3 - 8449130 - Nantucket Island, MA 2 mi64 min E 14 G 18
44020 - NANTUCKET SOUND 19 mi64 min 57°F1015 hPa (-1.7)
WAXM3 - Waquoit Bay Reserve, MA 33 mi79 min NE 2.9 58°F 1015 hPa57°F
BZBM3 - 8447930 - Woods Hole, MA 37 mi70 min 57°F 59°F1015.3 hPa
44090 42 mi34 min 57°F2 ft

Wind History for Nantucket Island, MA
(wind in knots)    EDIT      (on/off)   Help
8
PM
9
PM
10
PM
11
PM
12
AM
1
AM
2
AM
3
AM
4
AM
5
AM
6
AM
7
AM
8
AM
9
AM
10
AM
11
AM
12
PM
1
PM
2
PM
3
PM
4
PM
5
PM
6
PM
7
PM
Last
24hr
NE12
G15
NE10
G15
NE10
G13
NE10
G16
NE8
G12
NE6
G10
NE7
G13
NE10
G15
NE8
G14
NE9
G14
NE7
G14
NE7
G11
NE7
G11
NE8
NE8
G11
NE10
G15
NE9
G12
NE8
G13
NE7
G11
NE8
G12
NE10
G14
NE9
G13
E14
G20
E14
G17
1 day
ago
E4
G9
E7
E7
G10
E7
G10
E6
G11
SE6
E9
G12
E9
NE9
G14
E13
G17
NE12
G21
NE14
G18
NE15
G21
NE12
G19
NE13
G19
NE12
G18
NE14
G19
N10
G15
NE11
G21
N11
G16
NE12
G19
NE10
G15
N10
G16
NE11
G16
2 days
ago
SW3
W1
W3
SW3
SW2
--
--
--
--
--
--
S2
S1
SE4
S4
G8
S4
G8
SE5
G8
S4
G9
SE4
G7
SE3
SE2
E4
E5
E5

Airport Reports
    EDIT      (on/off)   Help   Click EDIT to display multiple airports. Follow links for more data.
AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Nantucket, Nantucket Memorial Airport, MA1 mi71 minE 15 G 223.00 miFog/Mist58°F55°F93%1014.8 hPa

Link to 5 minute data for KACK

Wind History from ACK (wind in knots)
9
PM
10
PM
11
PM
12
AM
1
AM
2
AM
3
AM
4
AM
5
AM
6
AM
7
AM
8
AM
9
AM
10
AM
11
AM
12
PM
1
PM
2
PM
3
PM
4
PM
5
PM
6
PM
7
PM
8
PM
Last 24hrN12NE11NE13NE12
G18
NE10NE9NE11NE11NE11NE12NE9NE8NE9NE11NE14E11E12NE11NE10NE12NE13E11
G20
E15
G22
E12
G19
1 day agoE7E8E7E7E8E6NE8NE10E13NE16NE17
G24
NE17
G25
NE17
G24
NE17
G23
NE16
G27
NE18
G24
N19
G24
N20
G27
N18
G28
N16N18N15NE13N13
2 days agoNW3NW3W3W3CalmCalmCalmCalmCalmCalmCalmSE3SE6S8SE10SE8SE8SE8SE7E4E6E5E5E6

Tide / Current Tables for Nantucket, Nantucket Island, Nantucket Island, Massachusetts
   EDIT   Weekend mode (on/off)   (on/off)   Help   One Week of Data
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.


Tide / Current Tables for Nantucket Harbor Entrance Channel, Massachusetts Current
   EDIT      (on/off)   Help   One Week of Data
Nantucket Harbor Entrance Channel
Click for Map
Tue -- 12:01 AM EDT     Moonrise
Tue -- 01:08 AM EDT     0.00 knots Slack
Tue -- 03:11 AM EDT     1.24 knots Max Flood
Tue -- 05:45 AM EDT     -0.00 knots Slack
Tue -- 06:59 AM EDT     Sunrise
Tue -- 11:44 AM EDT     -1.11 knots Max Ebb
Tue -- 01:49 PM EDT     0.00 knots Slack
Tue -- 03:00 PM EDT     Moonset
Tue -- 03:38 PM EDT     1.00 knots Max Flood
Tue -- 05:49 PM EDT     Sunset
Tue -- 05:50 PM EDT     -0.00 knots Slack
Tue -- 07:50 PM EDT     -0.46 knots Max Ebb
Tue -- 08:37 PM EDT     -0.45 knots Min Ebb
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

12
am
1
am
2
am
3
am
4
am
5
am
6
am
7
am
8
am
9
am
10
am
11
am
12
pm
1
pm
2
pm
3
pm
4
pm
5
pm
6
pm
7
pm
8
pm
9
pm
10
pm
11
pm
-0.8-0.10.71.210.4-0.1-0.3-0.4-0.4-0.7-1-1.1-0.70.20.910.5-0.1-0.4-0.5-0.5-0.6-0.9

Weather Map
       (on/off)   Help Weather Map
wmap_A
GEOS 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.
Link to Loop

Other links: Northern Pacific     Contential US     Full GOES-East
Wind Forecast for Boston, MA (20,4,5,8)
      (on/off)   Help

Ground Weather Radar Station Boston, MA
   (on/off)   Help
weather_mapweather_map weather_map

Ad by Google

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.