Thursday, August17, 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 6:09AMSunset 7:00PM Thursday August 17, 2017 5:29 AM HST (15:29 UTC) Moonrise 2:06AMMoonset 3:40PM Illumination 22% Phase: Waning Crescent; Moon at 25 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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PHZ116 Kaiwi Channel- 330 Am Hst Thu Aug 17 2017
Today..Northeast winds 15 knots. Wind waves 5 feet. Isolated showers through the day.
Tonight..Northeast winds 20 knots. Wind waves 5 feet. Isolated showers.
Friday..Northeast winds 15 knots. Wind waves 4 feet. Isolated showers through the day.
Friday night..Northeast winds 15 knots. Wind waves 4 feet. Scattered showers in the evening. Isolated showers after midnight.
Saturday..Northeast winds 15 knots. Wind waves 4 feet. Isolated showers.
Saturday night..Northeast winds 15 knots. Wind waves 4 feet. Scattered showers in the evening, then isolated showers after midnight.
Sunday..East winds 15 knots. Wind waves 4 to 5 feet. Scattered showers.
Monday..East winds 15 knots. Wind waves 5 to 6 feet. Scattered showers.
PHZ100 330 Am Hst Thu Aug 17 2017
Synopsis for hawaiian coastal waters.. A surface high far northeast of the islands will continue to move slowly east.

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


Area Discussion for -
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Fxhw60 phfo 171333
afdhfo
area forecast discussion
national weather service honolulu hi
333 am hst Thu aug 17 2017

Synopsis
Moderate to locally breezy trade winds will continue through the
remainder of the work week, then ease to light and moderate
levels this weekend. The trade winds will deliver periods of
clouds and showers to windward areas, with showers most active
during nights and mornings. While leeward areas of the smaller
islands will remain mostly dry, the leeward side of the big island
will see clouds and a few showers during the afternoon and
evening hours each day. An increase in trade wind showers is
possible late in the weekend through early next week.

Discussion
Currently at the surface, a 1027 mb high centered around 1625
miles northeast of honolulu is driving moderate trade winds
across the island chain early this morning. Meanwhile, invests
90c and 91c remain around 700-750 miles southeast of hilo.

Infrared satellite imagery shows scattered to broken cloud cover
drifting into windward areas with the trades, with partly cloudy
conditions prevailing in most leeward locales. Radar imagery
shows scattered showers moving into windward areas, with a few of
the showers drifting leeward from time to time. Main short term
concern over the next couple of days revolves around rain chances.

Today through Friday night,
high pressure northeast of the state will keep a moderate to
locally breezy trade wind flow in place through Friday, with a
slight easing of the trades expected Friday night. Precipitable
water (pw) values are forecast to remain below normal through the
period, generally in the 1.0 to 1.3 inch range. This in
combination with weak mid and upper level ridging should keep a
fairly dry and stable trade wind weather pattern in place through
the period. There could be a slight increase in trade wind showers
Friday night however, as mid upper level ridging breaks down in
response to an upper level low north of the state pivoting
southwestward and closer to the island chain. Overall, clouds and
showers will favor windward and mauka areas, with a few showers
reaching leeward locales from time to time. Showers will be most
prevalent during the overnight and early morning hours.

Saturday through next Wednesday,
high pressure will hold in place to the north and northeast of the
state through the period, keeping the trade winds blowing across
the island chain. An upper level low to the north of the islands
will induce weak surface troughing over and to the north of the
state, and this will weaken the trade winds into the light to
moderate range over the weekend. Early next week the upper level
low and weak surface trough are expected to retrograde west of the
islands. At the same time, both the GFS and ECMWF show an area of
low pressure (the consolidated low associated with invests 90c
and 91c) passing by to the south of the state. This should
strengthen the trade winds slightly early next week, with the
trades once again reaching moderate to locally breezy levels by
the middle of next week.

As for sensible weather details, the models are in good agreement
showing fairly dry trade wind weather prevailing through Saturday.

The GFS then begins to bring in some deep tropical moisture in
association with the invest areas Saturday night. Meanwhile, the
ecmwf suggests the deeper moisture will hold off until Sunday
night. Given the dependence on the track and potential development
of the resultant low associated with the invest areas currently
to the southeast of the islands, forecast confidence is low with
respect to timing more showery weather back into the island chain.

What does appear more clear, is that we will see an increasingly
moist and unstable airmass moving into the area as the weekend
progresses, with this airmass then holding over the islands
through early next week. In fact, the GFS and ECMWF show well
above normal pw values in excess of 2 inches by early next week.

The combination of plenty of deep moisture and an unstable airmass
should result in a fairly wet trade wind pattern late in the
weekend through early next week, with some locally heavy rainfall
possible. In addition, humid weather will accompany this surge in
deeper moisture making it feel much more uncomfortable than
normal, with dewpoints surging into the lower and middle 70s.

Again, the forecast late in the weekend and early next week hinges
on the track and degree of development of the low passing by to
the south of the state. By the middle of next week, both the gfs
and ECMWF show a more stable and drier airmass working its way
back into the area, and this should lead to a return of more
typical trade wind weather across the island chain.

The central pacific hurricane center (cphc) continues to closely
monitor the two invest areas to the southeast of the islands for
potential development. Cphc is now forecasting a high chance for
a single tropical cyclone to emerge out of the two invest areas
over the next 2 to 3 days, before conditions become unlikely for
development. See the tropical weather outlooks issued by cphc for
additional details.

Aviation
High pressure northeast of the islands will keep moderate to
locally breezy trade winds in the forecast through Friday. Expect
mostlyVFR conditions with brief periods of MVFR ceilings and
scattered to numerous showers over northeastern slopes of all
islands. Isolated to scattered shower activity is forecast
elsewhere.

Airmet tango remains in effect this morning for low level
turbulence over and south through west of all mountains. Wind
speeds may decrease slightly by this evening enough to drop this
airmet. No additional airmet's are expected.

Marine
Surface high pressure far northeast of the islands will maintain
moderate to locally strong trades winds. This will continue to
result in small craft advisory (sca) conditions for the typically
windy waters adjacent to the islands of maui county and the big
island. The SCA for these areas has been extended through Friday
afternoon. The high is expected to continue drifting eastward
during the next few days, and a slight downward trend in trade
wind speeds is expected from Friday night through this weekend.

A small, long period south-southeast swell is expected to peak
late Friday, before gradually subsiding this weekend. A small,
reinforcing long-period southwest swell is forecast to reach the
islands Saturday, and continue into early next week.

Surf is expected to trend down along east facing shores this
weekend as the trades weaken slightly. Surf will likely remain
below the high surf advisory criteria along all shorelines
through the middle of next week.

Finally, another period of above normal high tides is expected
through this weekend. The water levels associated with these
tides are forecast to be slightly lower than those observed in
july. In addition, no large swells are expected during the next
several days. There could still be some localized coastal
flooding from these tides. See the special weather statement,
spshfo, for more details.

Hfo watches warnings advisories
Small craft advisory until 6 pm hst Friday for maalaea bay-
pailolo channel-alenuihaha channel-big island leeward waters-big
island southeast waters.

Discussion... Jelsema
aviation... Bohlin
marine... Houston


Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
OOUH1 - 1612340 - Honolulu, HI 1 mi42 min ENE 1 G 1.9 78°F 80°F1015.4 hPa
51211 4 mi60 min 80°F3 ft
MOKH1 - 1612480 - Mokuoloe, HI 11 mi54 min E 8.9 G 9.9 79°F 81°F1015 hPa
51210 14 mi30 min 81°F3 ft
51202 - Mokapu Point, HI (098) 14 mi56 min 80°F4 ft
51207 15 mi35 min 80°F3 ft
51201 - Waimea Bay, HI (106) 29 mi28 min 78°F3 ft

Wind History for Honolulu, HI
(wind in knots)    EDIT      (on/off)   Help
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Last
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N2
NE3
G9
NE3
G8
NE7
G10
NE8
G11
E4
G7
NE5
G11
E3
G11
NE6
G10
NE9
G15
NE6
G15
NE10
E1
G7
NE6
G14
NE7
G11
E3
E3
E3
G6
NE3
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NE3
NE2
G6
E1
1 day
ago
E2
G8
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G6
NE3
G7
NE4
G12
E6
G10
E5
G12
E7
G14
NE5
G12
NE5
G10
NE6
G14
NE7
G12
NE8
G16
E4
G13
NE7
G10
NE7
G11
NE4
G10
E7
G13
E2
G7
E6
G11
E4
G7
E3
G9
N4
NE3
G6
SE1
G4
2 days
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E3
G6
NE4
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G10
E2
G5
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G9
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G14
E7
G16
NE6
G12
E4
G12
E6
G10
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G13
NE6
G13
NE6
G10
E5
G8
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G9
NE2
G5
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G8
NE3
G9
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G7
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G13
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G9
NE7
G11
E2
G6
E2
G7

Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Honolulu, Honolulu International Airport, HI5 mi37 minNNE 510.00 miA Few Clouds76°F66°F74%1014.5 hPa
Oahu, Kalaeloa Airport, HI10 mi37 minENE 310.00 miA Few Clouds73°F64°F76%1015.7 hPa
Kaneohe, Marine Corps Air Station, HI12 mi4.5 hrsENE 87.00 miMostly Cloudy80°F70°F71%1014.3 hPa
Wheeler Air Force Base / Oahu, HI15 mi32 minWNW 510.00 miA Few Clouds67°F66°F98%1014.2 hPa

Wind History from HNL (wind in knots)
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Last 24hrN4NE4NE9NE10E15E12NE15
G24
NE13
G25
E14
G18
NE15NE13E15
G21
NE12NE12NE9NE12NE11
G16
NE9
G18
E11NE10NE6E8N5NE5
1 day agoE5E8E10E8NE10E15E16
G21
NE16
G22
NE15
G23
NE13
G20
NE14
G20
NE13
G23
NE12NE14
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NE10NE10NE10E9NE7NE10E8NE6NE6E6
2 days agoE9E9NE9E7NE9E10NE12E13
G21
E17
G24
NE18
G21
E15
G24
E18
G23
NE13
G21
NE13
G20
NE10NE14E8NE10NE10NE8E9E9NE5E6

Tide / Current Tables for Honolulu, Honolulu Harbor, Oahu Island, Hawaii
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Honolulu
Click for Map
Thu -- 02:06 AM HST     Moonrise
Thu -- 05:46 AM HST     -0.02 feet Low Tide
Thu -- 06:10 AM HST     Sunrise
Thu -- 01:17 PM HST     2.27 feet High Tide
Thu -- 03:39 PM HST     Moonset
Thu -- 06:59 PM HST     Sunset
Thu -- 08:24 PM HST     0.32 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
0.90.80.70.40.20-00.10.40.81.31.82.12.32.221.61.20.80.50.30.30.50.7

Tide / Current Tables for Hanauma Bay, Oahu Island, Hawaii
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Hanauma Bay
Click for Map
Thu -- 02:06 AM HST     Moonrise
Thu -- 05:02 AM HST     0.10 feet Low Tide
Thu -- 06:10 AM HST     Sunrise
Thu -- 12:21 PM HST     2.28 feet High Tide
Thu -- 03:39 PM HST     Moonset
Thu -- 06:59 PM HST     Sunset
Thu -- 07:45 PM HST     0.41 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
0.90.70.50.30.20.10.20.40.81.31.72.12.32.221.71.30.90.60.50.40.50.70.9

Weather Map and Satellite Images
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Weather Map
wmap_P
IR Satellite Image from GEOS
cpac_satellite

GOES Local Image of Hawaii    EDIT
Geos

Wind Forecast for (11,2,3,4)
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Ground Weather Radar Station Molokai, HI
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weather_mapweather_map weather_map

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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.