surf zone forecast
National Weather Service Honolulu HI
700 PM HST Tue Nov 10 2009
hiz005>011-111900-
Oahu-
700 PM HST Tue Nov 10 2009
Surf along north facing shores will be 3 to 5 feet...increasing to 5
to 8 feet Wednesday.
Surf along west facing shores will be 1 to 3 feet through Wednesday.
Surf along south facing shores will be 2 to 4 feet through Wednesday.
Surf along east facing shores will be 2 to 4 feet through Wednesday.
Outlook through Monday Nov 16:
a short period north swell is expected to arrive Thursday...
gradually turning to the east by the weekend. Surf heights are
expected to exceed the 8 foot advisory level on the east facing
shores through the weekend.
Surf heights are forecast heights of the face or front of waves. The
surf forecast is based on the significant wave height...the average
height of the one third largest waves...in the zone of maximum
refraction. Some waves may be more than twice as high as the
significant wave height. Expect to encounter rip currents in or near
any surf zone.
&&
Collaborative nearshore swell and wind forecast for Oahu
NWS/ncddc Honolulu HI
300 PM HST Mon Nov 9 2009
This collaborative forecast will be updated Monday through Friday at
300 PM when pat Caldwell is available. When pat Caldwell is not
available...the latest collaborative forecast will remain posted for
4 days.
Forecast swl dmnt dmnt h h hgt wind wind spd
date hgt dir pd 1/3 1/10 tend prob spd dir tend
1 PM 4 NNW 11 6 8 down 13-19 ENE down
11/09 6 ENE 7 2 4 same
2 S 13 2 4 same
Tue 3 N 10 4 6 down low 11-16 NE same
11/10 6 ENE 7 2 4 same Med
2 SSW 14 2 4 up low
Wed 7 NNE 10 6 10 up low 7-10 ESE down
11/11 2 SSW 14 2 4 same low
Thu 9 NE 10 8 12 same low 11-16 ESE up
11/12 2 S 13 2 4 same low
Fri 10 ENE 10 8 12 up low 11-16 ESE same
11/13 2 S 12 2 4 same low
Sat 11 ENE 10 8 14 same low 17-21 E up
11/14 2 S 13 2 4 same low
Legend:
swl hgt open ocean swell height measured from trough to crest
in feet located 20 nautical miles offshore
dmnt dir dominant direction typically +/-10 degrees in 16 Compass
points
dmnt pd dominant period in seconds
h1/3 significant wave height in the surf zone
h1/10 average height of the highest one-tenth waves in the surf
zone
hgt tend height tendency of swell (valid values: up/down/same)
prob probability of occurrence (valid values: high/Med/low)
wind spd open water wind speed measured in knots located
20 nautical miles offshore
wind dir wind direction in 16 Compass points
spd tend wind speed tendency (valid values: up/down/same)
Surf heights will vary between different beaches and at the same
beach at different break areas.
Discussion:
summary...
windswell from N to E to top The Heights.
Detailed...
mid-Monday on northern shores has small breakers from 330-020
degrees with 8-14 second periods. It is mostly associated with
angular spreading from the Gulf of Alaska source from late last
week. This episode is expected to decline on Tuesday.
The North Pacific jet stream has favored a blocking ridge meandering
around the dateline and a trough in the Gulf of Alaska. This general
pattern is expected to continue into next week...making for below
average surf conditions with dominant swell from NNW to NNE.
A large high pressure is intensifying north of Hawaii to the west
side of a deepening jet stream trough over the Gulf of Alaska. The
trough is modelled to have a southwestward extension. See the latest
NWS state weather forecast discussion for local implications of this
developing winter system. At the surface...strong to near gale winds
are expected to increase over a wide fetch from the 010-040 degree
band from about 400 to 1200 nm away on Tuesday into Wednesday.
Short-period swell of 8-12 seconds is expected to build rapidly mid
Wednesday...bringing surf to moderate levels relative to North Shore
standards late afternoon for zones that typically receive wave
energy from 010-040 degrees. The episode is expected to be
long-lived...with a downward trend on North Shores going into the
weekend as the dominate direction rotates toward 70 degrees.
Mid-Monday on Eastern Shores has mostly small breakers except for
locations with northerly exposure. The source described above should
bring rough...high surf relative to eastern means starting Wednesday
afternoon and continuing into the weekend.
Moderate trades on Tuesday are expected to become lighter on
Wednesday when the unsettled local weather pattern is predicted to
unfold...with the exceptions of localized gusts associated with
cloud or rain bands. This weather feature is expected to weaken and
drift west near the weekend...allowing moderate to fresh trades to
return in its wake.
Mid-Monday on Southern Shores has small breakers from 180-200
degrees. More of the same is expected through the period.
A pair of extratropical cyclones tracked eastward along about 65s
latitude S to se of New Zealand last week. Swell was aimed mostly at
the americas. Angular spreading could keep a tiny to small episode
locally through the period.
Into the long range...a long wave trough in the jet stream is
developing to the east of New Zealand. A series of surface low
pressure systems are expected to track into a favorable area for
Hawaii surf production. This should lead to an extended period of
above average southerly swell starting next Monday with peak days
at moderate to near high surf. The pattern could last about a week
to 10 days with dominant direction from 180-200 degrees.
In the northern hemisphere...models show a fast-moving low with
severe gales crossing the dateline hugging the Aleutians roughly
Friday night that could bring in a small to moderate...short-lived
episode from NNW by late next Monday. Models suggest fresh trades
next week with moderate to high easterly windswell.
Long range forecasts are subject to low confidence.
This collaborative forecast will resume on Thursday...November 12.
This forecast was produced through the collaborative efforts of
NWS and ncddc. Please send suggestions to W-hfo.Webmaster@noaa.Gov
or call the warning coordination meteorologist at 808-973-5275.
Additional resources:
see /in lowercase/ http://www.Prh.NOAA.Gov/hnl/pages/marine.Php
$$
NWS forecaster Craig and ncddc pat Caldwell
