Marine Weather and Tides
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 6:42AM||Sunset 5:51PM||Wednesday November 14, 2018 1:30 PM HST (23:30 UTC)||Moonrise 12:15PM||Moonset 11:33PM||Illumination 44%|
7 Day Forecast for Marine Location Near Kekaha, HIHourly EDIT Help
Area Discussion for -  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxhw60 phfo 141934|
area forecast discussion
national weather service honolulu hi
934 am hst Wed nov 14 2018
Trade winds will weaken today as a front passes far north of the
state. Sea breezes are expected over the islands later in the
day. A wet trade wind pattern will develop during the latter half
of the work week and last into the weekend as a surface high
builds to our north and an upper trough moves over the area.
A front far north of the main hawaiian islands has put a dent in
the subtropical ridge, causing trade winds to decrease across
local waters this morning. Patchy high clouds partially obscure
the view of lower clouds, but satellite and radar loops show low
level winds have veered to southeasterlies over the past 12 hours
and continue to push scant showers across windward portions of the
big island. Earlier showers across windward oahu have dissipated.
Overnight soundings show a dry and stable airmass, with less than
an inch of pw and positive lifted index values. Strong inversions
are noted as well, with bases near 6400 feet.
Models show the front will pass eastward and remain north of the
main island chain today, keeping winds light across the area into
Thursday. Sea breezes will develop over the islands during the
day, especially across leeward and mauka areas. Weak synoptic wind
flow across the islands will produce a mixed trade wind and
convective weather pattern today, with low clouds embedded within
decreased trade flow occasionally reaching windward areas. Our
airmass will remain stable and somewhat dry, limiting any
rainfall. Patchy high clouds will remain with us for the next few
days as upper level moisture pushes in from the west within a
subtropical jetstream. Surface winds will remain light enough for
development of land breezes tonight, resulting in some clearing
over the islands.
High pressure will build in from the northwest and bring trade
winds back to the state beginning Thursday. Trades may become
locally breezy over the weekend. A strong upper trough with cold
mid-level air will begin to affect our weather towards the
weekend, enhancing trade wind showers. This upper trough will move
over the islands and may develop into an upper low that will
linger in the area over much of the weekend. Models also show
moisture from the old frontal band may reach the state within
returned trade flow at the same time. A wet trade wind weather
pattern is in store for the islands by the weekend, especially for
windward areas which could see some locally heavy rainfall at
times. Thanks to the upper trough, our airmass may become unstable
enough for a few thunderstorms to develop as well.|
The upper trough should begin to weaken and push eastward early
next week, allowing for gradually improving weather with
relatively drier and possibly locally breezy trades.
Weak trades will become negligible in light flow. Thus, this
morning's land breezes will give way to pronounced sea breezes
developing late this morning through the afternoon. Land breezes
will then take over again tonight.
Relatively dry air over the area will prevent widespread or heavy
shower activity. Expect isolated showers to focus over interior
and leeward sections of the state this afternoon. Only mvrf
concern may be low ceilings at phny during the afternoon, otherwise
vfr conditions will prevail.
Light easterly winds are expected through Thursday night as a
front passes by far north of the area. High pressure will build
back in north of the area on Friday and remain in place through
the weekend. Trade winds will likely become strong enough
requiring a small craft advisory over the typically windy waters
around maui county and the big island.
The current advisory level north northwest swell will lower
gradually today through Thursday. A new advisory level northwest
swell is expected to arrive Thursday night, peak on Friday, then
lower gradually Friday night and Saturday. A slightly smaller
north northwest swell is expected Saturday night and Sunday.
Another small to moderate size northwest swell is expected to
arrive on Monday. Small, mainly background south swells are
expected through the remainder of the week and on through the
weekend. A slight uptick in short period choppy surf can be
expected Friday through Sunday as the trade winds pick back up.
An upper level trough expected to be over the area Thursday night
through Saturday, will cause the airmass to become unstable over
the area with heavier shower and isolated thunderstorms becoming a
Hfo watches warnings advisories
High surf advisory until 6 pm hst this evening for niihau-kauai
windward-kauai leeward-oahu north shore-oahu koolau-molokai-maui
windward west-maui central valley-windward haleakala.
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GOES Local Image of Hawaii 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 (18,4,5,8)(on/off)  Help
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