Tuesday, November21, 2017 L-36.com


Marine Weather and Tides
Urban Honolulu, HI

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 6:45AMSunset 5:49PM Tuesday November 21, 2017 12:16 AM HST (10:16 UTC) Moonrise 9:26AMMoonset 8:42PM Illumination 7% Phase: Waxing Crescent; Moon at 3 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
PHZ116 Kaiwi Channel- 900 Pm Hst Mon Nov 20 2017
.small craft advisory in effect through Tuesday morning...
Rest of tonight..Northeast winds 15 knots. Wind waves 3 feet. North swell 10 feet. Isolated showers early in the evening, then scattered showers after midnight.
Tuesday..Northeast winds 15 knots. Wind waves 3 feet. North swell 9 feet. Isolated showers in the morning.
Tuesday night..Northeast winds 15 knots. Wind waves 4 feet. North swell 7 feet. Isolated showers in the evening, then scattered showers after midnight.
Wednesday..Northeast winds 15 knots. Wind waves 4 feet. North swell 8 feet increasing to 10 feet in the afternoon. Scattered showers in the morning, then isolated showers in the afternoon.
Wednesday night..Northeast winds 20 knots. Wind waves 5 feet. North swell 11 feet. Scattered showers.
Thursday..Northeast winds to 25 knots. Wind waves 8 feet. North swell 12 feet. Scattered showers in the morning.
Thursday night..Northeast winds to 25 knots. Wind waves 8 feet. North swell 11 feet. Isolated showers through the night.
Friday..Northeast winds to 25 knots. Wind waves 8 feet. North swell 8 to 10 feet. Isolated showers.
Saturday..East winds to 25 knots. Wind waves 7 feet. North swell 6 to 7 feet. Scattered showers.
PHZ100 900 Pm Hst Mon Nov 20 2017
Synopsis for hawaiian coastal waters.. A surface low northeast of the state will maintain northerly winds over the hawaiian coastal waters overnight, while a lingering north swell keeps seas elevated. Winds will veer slightly to the northeast on Tuesday as the low weakens and moves farther away. Strong high pressure will build northwest of the area during the second half of the week, resulting in strong and gusty northeast trade winds over the coastal waters. Another large north swell is expected to move through the area beginning late Wednesday and continuing through Thursday night.

7 Day Forecast for Marine Location Near Urban Honolulu, HI
   Hourly   EDIT   Help
location: 21.29, -157.88     debug


Area Discussion for -
      (on/off)   Help   NOTE: mouseover dotted underlined text for definition
Fxhw60 phfo 210628
afdhfo
area forecast discussion
national weather service honolulu hi
828 pm hst Mon nov 20 2017

Synopsis
A surface low far northeast of the islands will continue to move
away from the region, while an upper level trough will remain
over the area through this weekend. Low clouds and showers will
remain focused along north facing slopes and coasts tonight. A
strong new surface high will build far northwest of the area on
Wednesday, then move southeast into early next week. Gusty trade
winds are expected thanksgiving and Friday, before easing slightly
this weekend. Expect windward trade showers, occasionally
spreading leeward.

Discussion
The pressure gradient between a surface high far northwest of the
islands and a surface low far northeast of the region is
producing light to locally moderate northerly winds. This low-
level flow continues to advect cool and relatively dry air into
the islands. Aloft, loops of water-vapor satellite imagery
indicate middle- and upper-tropospheric troughing extends
northeast from the islands. This upper-level troughing is having
little significant affect on atmospheric stability across the
state. A significant low-level temperature inversion of around 5
thousand feet was observed on kauai, and increased to near 7
thousand feet over the eastern big island in the early afternoon
balloon soundings.

The northerly winds continue to transport isolated showers over
north and northeast facing slopes and coasts early this evening
according to loops of satellite imagery and radar reflectivity
data. However, rainfall will continue to be relatively light over
most areas. Note that there is a chance the north winds, and some
slightly higher inversion heights could boost rainfall along
portions of the north and northeast slopes of the big island later
tonight and early Tuesday morning.

The trough aloft continues to produce strong west winds over the
summits of mauna kea and mauna loa on the big island of hawaii. As
a result, a high wind warning has been issued for the summits
through early Tuesday morning. The winds are expected to gradually
subside as the trough weakens later tonight and Tuesday. We
expect to issue a wind advisory for the summits on Tuesday once
the high wind warning is lowered.

Through Wednesday, we anticipate the surface low far northeast of
the area will move northeastward and weaken, while the surface
high moves southeastward and weakens. Winds over the islands will
gradually shift out of the northeast Tuesday. The forecast
guidance shows a low-cloud band moving down from the northwest and
reaching kauai county by Tuesday afternoon. This feature is
expected to then move over oahu and maui county Tuesday night,
before pushing down over the big island by Wednesday evening. This
cloud band will bring an increase in low clouds and showers,
especially over windward areas.

Starting Wednesday night, a new strong surface high far northwest
of the islands will start moving southeast. The northeast trade
winds over the islands will strengthen and become breezy. Wind
speeds will likely decrease again starting Saturday, but trade
winds will likely persist through early next week.

Aviation
Cool northerly winds will continue to push bands of clouds and
showers over the islands tonight. The highest coverage for shower
activity will occur over mountain areas and the northern slopes of
all islands. Relatively drier air will lead to higher than normal
cloud bases.VFR conditions prevail with only isolated MVFR in
moderate showers.

No airmets are in effect and none are expected.

Marine
Surf along the north-facing shores of the state remains elevated.

Evening buoy observations show little change during the past
several hours, and heights remain above wave watch iii guidance.

The effect of the low bias in the guidance is that surf height
will remain above high surf advisory (hsa) criteria through
Tuesday morning. The north swell is expected to diminish Tuesday
afternoon.

A small craft advisory (sca) remains in effect for all hawaiian
waters except maalaea bay and waters south of the big island due
to the large north swell causing the combined seas to be above the
10-foot threshold. With wave heights running above guidance, the
sca has been extended through Tuesday morning.

Winds over the coastal and offshore waters remain generally from
the north due to a low pressure system northeast of the state.

The low is in the process of weakening and moving northeastward
away from the island chain. As this occurs, a high pressure ridge
will slowly build north of the forecast area through the week.

Winds will slowly veer toward a trade wind direction and increase,
reaching SCA levels Wednesday with near gale-force winds possible
in some of the channels by Thursday.

In addition to the increasing trades, a new north-northeasterly
swell is forecast to arrive later this week. The swell is
currently projected to be a few feet larger than the current swell
with a slightly longer period. This will translate to possible
warning level surf for north facing shores, building late
Wednesday and peaking on thanksgiving day. The swell direction
will result in some wrap into the east facing shores so warning
level surf is a possibility for these areas as well.

Hfo watches warnings advisories
High surf advisory until noon hst Tuesday for north facing shores
of niihau, kauai, oahu, molokai, maui, and the big island.

High wind warning until 6 am hst Tuesday for the big island
summits.

Small craft advisory until noon hst Tuesday for kauai northwest
waters-kauai windward waters-kauai leeward waters-kauai channel-
oahu windward waters-oahu leeward waters-kaiwi channel-maui
county windward waters-maui county leeward waters-pailolo
channel-alenuihaha channel-big island windward waters.



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
OOUH1 - 1612340 - Honolulu, HI 1 mi47 min Calm G 1.9 70°F 79°F1015 hPa
51211 4 mi47 min 78°F1 ft
MOKH1 - 1612480 - Mokuoloe, HI 11 mi47 min NNE 14 G 18 75°F 76°F1014.3 hPa
51210 14 mi47 min 78°F10 ft
51202 - Mokapu Point, HI (098) 14 mi43 min 79°F11 ft
51201 - Waimea Bay, HI (106) 29 mi45 min 77°F13 ft

Wind History for Honolulu, HI
(wind in knots)    EDIT      (on/off)   Help
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
Last
24hr
N3
NW3
N3
N2
N2
NW4
E1
--
NW4
W5
N3
G6
N9
E8
G12
NE4
G7
NE4
G9
E5
G12
NE7
G13
N4
G9
SE1
N3
G6
W1
G5
N8
G13
E3
G6
NW3
1 day
ago
N1
NW4
N2
NW3
--
NW3
N3
N2
G6
N3
NW6
NW8
G11
N6
G11
NW10
G13
N7
G12
N5
G10
NE5
G13
N8
G11
N5
G8
N2
N3
G6
NW3
N2
N4
G10
N3
2 days
ago
E1
--
E1
NW2
W2
SW4
SW6
S4
G8
SW5
G8
SW5
G8
SW6
SW4
G7
NE3
G6
E4
G7
NE3
N4
G9
N2
G6
N2
NE2
G5

Airport Reports
    EDIT      (on/off)   Help   Click EDIT to display multiple airports
AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Honolulu, Honolulu International Airport, HI5 mi24 minNNW 510.00 miMostly Cloudy72°F61°F68%1014.2 hPa
Oahu, Kalaeloa Airport, HI10 mi24 minNNE 310.00 miFair69°F59°F70%1015.3 hPa
Kaneohe, Marine Corps Air Station, HI12 mi80 minNNE 1410.00 miOvercast74°F61°F64%1013 hPa
Wheeler Air Force Base / Oahu, HI15 mi21 minWNW 410.00 miFair62°F59°F91%1014.9 hPa

Wind History from HNL (wind in knots)
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
12
AM
Last 24hrNW6N8N4SW4CalmNW7N5NW5NW8N11
G15
NW10NW9
G17
4N10N9N10N8N5NW5NW5N11NW4NW5NW5
1 day agoNW4N3N4NW4NW5NW7NW7N5NW9NE7NW14
G21
NW16
G19
NW13
G21
NW12N10N10N10N5N4NW45NW8NW6NW5
2 days agoNW6NW4N3N4NW3N3N53NW4N4N4SW10S6S9S7N10
G16
NW10
G17
NW10N4N8N4NW7N7N5

Tide / Current Tables for Honolulu, Honolulu Harbor, Oahu Island, Hawaii
   EDIT   RT Ports Option   Weekend mode (on/off)   (on/off)   Help   One Week of Data
Honolulu
Click for Map
Tue -- 05:47 AM HST     2.17 feet High Tide
Tue -- 06:46 AM HST     Sunrise
Tue -- 09:25 AM HST     Moonrise
Tue -- 01:12 PM HST     0.34 feet Low Tide
Tue -- 05:42 PM HST     0.72 feet High Tide
Tue -- 05:48 PM HST     Sunset
Tue -- 08:41 PM HST     Moonset
Tue -- 10:50 PM HST     0.19 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
0.30.61.11.51.92.12.221.71.410.70.40.30.40.50.60.70.70.60.50.40.20.2

Tide / Current Tables for Hanauma Bay, Oahu Island, Hawaii
   EDIT      (on/off)   Help   One Week of Data
Hanauma Bay
Click for Map
Tue -- 04:51 AM HST     2.13 feet High Tide
Tue -- 06:45 AM HST     Sunrise
Tue -- 09:24 AM HST     Moonrise
Tue -- 12:33 PM HST     0.40 feet Low Tide
Tue -- 04:48 PM HST     0.75 feet High Tide
Tue -- 05:47 PM HST     Sunset
Tue -- 08:41 PM HST     Moonset
Tue -- 10:06 PM HST     0.27 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
0.611.41.82.12.121.81.41.10.80.50.40.40.50.60.70.70.70.60.40.30.30.3

Weather Map and Satellite Images
       (on/off)   Help
Weather Map
wmap_P
IR Satellite Image from GEOS
cpac_satellite

GOES Local Image of Hawaii    EDIT
Geos

Wind Forecast for (5,6,7,8)
      (on/off)   Help

Ground Weather Radar Station Molokai, HI
   (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.