Thursday, August17, 2017 L-36.com


Marine Weather and Tides
Captain Cook, 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 6:00AMSunset 6:47PM Thursday August 17, 2017 5:35 AM HST (15:35 UTC) Moonrise 2:01AMMoonset 3:29PM 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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PHZ123 Big Island Leeward Waters- 330 Am Hst Thu Aug 17 2017
.small craft advisory in effect through Friday afternoon...
Today..West of the big island, southeast winds 10 knots veering west in the afternoon. NEar south point, east winds to 25 knots. Wind waves 6 feet. Isolated showers in the morning. Haze through the day.
Tonight..West of the big island, northwest winds 10 knots in the evening becoming variable less than 10 knots. NEar south point, east winds to 25 knots. Wind waves 6 feet. Haze through the night. Isolated showers after midnight.
Friday..West of the big island, winds variable less than 10 knots becoming southwest 10 knots in the afternoon. NEar south point, east winds to 25 knots. Wind waves 6 feet. Isolated showers in the morning. Haze through the day.
Friday night..Winds variable less than 10 knots west of the big island...east 20 knots near south point. Wind waves 6 feet. Haze through the night. Isolated showers through the night.
Saturday..Winds variable less than 10 knots west of the big island...east 20 knots near south point. Wind waves 5 feet. Isolated showers in the morning. Haze through the day.
Saturday night..Winds variable less than 10 knots west of the big island...northeast 15 knots near south point. Wind waves 6 feet. Haze through the night. Isolated showers through the night.
Sunday..West of the big island, winds variable less than 10 knots. NEar south point, east winds 10 knots rising to 20 knots after midnight. Wind waves 5 to 6 feet. Haze. Isolated showers.
Monday..Winds variable less than 10 knots west of the big island...east 15 knots near south point. Wind waves 5 to 6 feet. Haze. Isolated 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 Captain Cook, HI
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location: 19.46, -155.96     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
KWHH1 40 mi48 min NE 2.9 G 5.1 76°F 82°F1013 hPa
ILOH1 - 1617760 - Hilo, HI 51 mi54 min SW 2.9 G 2.9 73°F 81°F1014.2 hPa

Wind History for Kawaihae, HI
(wind in knots)    EDIT      (on/off)   Help
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Kailua / Kona, Keahole Airport, HI13 mi43 minSE 610.00 miOvercast78°F66°F67%1012.7 hPa

Wind History from HKO (wind in knots)
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Last 24hrE4NE5CalmW8SW7S11SW11W9SW12S12S11S11S10S9SE5E8E9SE4SE3CalmCalmCalmSE6SE6
1 day agoNE3E6S6S9S12S10S12SW10SW9S9S8S8S9SE7S65NE6NE5NE6NE6CalmCalmE3E4
2 days agoE6E3SE3SW5SW8SW7W8W9W11W9W10SW8SW6S5SE4CalmNW4SE6SE6SE7E6SE7NE5NE4

Tide / Current Tables for Kailua Kona, Big Island, Hawaii
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Kailua Kona
Click for Map
Thu -- 02:01 AM HST     Moonrise
Thu -- 05:30 AM HST     0.08 feet Low Tide
Thu -- 06:04 AM HST     Sunrise
Thu -- 12:54 PM HST     2.35 feet High Tide
Thu -- 03:29 PM HST     Moonset
Thu -- 06:50 PM HST     Sunset
Thu -- 08:01 PM HST     0.40 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
10.90.70.50.20.10.10.30.61.11.622.32.32.21.91.51.10.70.50.40.50.60.8

Tide / Current Tables for Kailua Kona, Hawaii Island, Hawaii
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Kailua Kona
Click for Map
Thu -- 02:01 AM HST     Moonrise
Thu -- 05:48 AM HST     -0.04 feet Low Tide
Thu -- 06:04 AM HST     Sunrise
Thu -- 01:17 PM HST     2.11 feet High Tide
Thu -- 03:29 PM HST     Moonset
Thu -- 06:50 PM HST     Sunset
Thu -- 07:57 PM HST     0.51 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
1.110.70.50.20-00.10.40.81.21.622.12.11.81.51.10.80.60.50.60.81

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 South Shore, 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.