1-5 foot
0-2 foot
1-4 foot
5-8+ foot

A High Surf Advisory is now in effect for the east facing shores of the Big Island, Maui, Kauai, Molokai and Oahu. It remains posted through Monday morning due to a mid- to long-period east swell associated with a fetch from when Tropical Depression Fernanda was a major hurricane. Some of this energy may wrap into select south and north facing shores. The largest high tides of the month will occur each afternoon during the next few days. Note that these high tides, combined with wave run-up due to the east swells produced by Fernanda, may result in coastal flooding in some areas through Monday. Elsewhere, no significant swells are expected. Small south swells will continue to produce background surf along south facing shores through the weekend and on into next week.

Over the offshore waters, there will be a chance of isolated thunderstorms over portions of the area from Saturday through Monday as an upper trough and increased moisture from Fernanda move across the area. Locally strong trade winds will continue to produce Small Craft Advisory (SCA) conditions for the typically windy waters around Maui County and the Big Island. The SCA, currently in effect though early Saturday morning, may be extended to noon if winds remain elevated.

Hawaii Wave Height Model

Hawaii Swell Period Model
Hawaii Swell Height Model

Tide Predictions

High tide at Kahului was 1.4 foot at 12:54 AM just after midnight, dropping to a low of -0.6 foot at 7:18 AM this morning, then rising to a high of 2.9 foot at 2:39 PM early this afternoon, before once again dropping to a low of 0.7 foot at 9:09 PM late this evening

The sunrise was at 05:55 am this morning and will set at 07:09 pm this evening. The Moon is currently 29 days old, and is in a New Moon phase. The next Waxing Crescent will occur at 12:51 AM on Saturday, July 1st.

Hawaii Wind Report

Maui Weather

Wind: n/a at 0 mph
current observations as of 7am October 20th, 2018

Weather Outlook for Saturday

An unsettled period is in the forecast for this weekend, and into early next week as an upper level trough interacts with low level moisture riding in with the trades, and then with deeper tropical moisture associated with weakening and dissipating Tropical Storm Fernanda early next week. Drier weather with lower humidity and strong trades will return by midweek.

A deepening upper level trough is currently in the works over the main Hawaiian Islands. This will result in a weaker inversion area wide, which will allow moisture currently capped at 10 to 13k feet, to rise to 15 to 20 kt feet by Saturday afternoon. The air mass will be unstable enough to support a thunderstorm or two over the higher terrain of the Big Island Saturday afternoon as well.

Currently, satellite imagery shows a blob of low clouds and embedded showers moving through the main Hawaiian Islands. Some what of a thinner cloud mass and a lower precipitable water follows close behind upwind of the smaller islands. Radar is picking up scattered showers favoring the windward and mountain areas of most islands. Off and on again sprinkles are reaching deep into the leeward areas of the smaller islands. Isolated showers are also present just off the Kona coast on the Big Island. This somewhat showery pattern should hold through at least Saturday morning.

As for Tropical Storm Fernanda, it is located just over 665 miles E of Hilo this evening. It is moving W at 8 mph. It is expected to continue to weaken as it moves in our general direction, becoming a remnant low and then a trough as it moves near or just N of Maui County on Monday.

The GFS is suggesting a pocket of lower PW’s, or drier air mass, to briefly affect the islands Saturday night and Sunday morning, before the arrival of the deep tropical air mass late Sunday. This is a good legitimate point which will take into consideration. Current forecast calls for a showery weather Saturday night through Sunday with the potential for locally heavy showers Sunday.

Up to Sunday, the trade winds will be modest in speed, but will turn lighter on Monday. The deep tropical moisture from dying Fernanda should be bleeding onto the Big Island as early as Sunday afternoon, and gradually spread westward across the rest of the islands through Monday night, raising the discomfort level. This injection of additional, deeper moisture, will result in some spotty heavy showers especially Monday afternoon, aided by daytime heating, light winds, and an already established unstable air mass brought on by the upper level trough.

The GFS and ECMWF models differ with the return of the drier air and stronger trade winds. The EC is faster with this occurring on Tuesday. The slower GFS has the improving weather happening Tuesday night. The past couple of GFS runs have not been all too favorable for us to use as it take Fernanda well north of the islands when the actual track has Fernanda coming close to the islands. But this slower drag of the tropical moisture may seem more reasonable. This is still a couple of days down the road. They should, and usually come to an agreement in due course.

Central Valley (Kahului, Spreckelsville):

Partly sunny. Breezy. Isolated showers in the morning, then scattered showers in the afternoon. Highs around 88. Northeast winds 10 to 20 mph. Chance of rain 50 percent.

Leeward West (Lahaina, Ka`anapali):

Partly sunny with scattered showers. Highs 82 to 89. East winds 10 to 15 mph. Chance of rain 50 percent.

Windward West (Wailuku, Waiehu):

HIGH SURF ADVISORY IN EFFECT UNTIL NOON HST MONDAY. Mostly cloudy. Scattered showers in the evening, then showers likely after midnight. Lows 61 to 73. East winds 10 to 15 mph. Chance of rain 70 percent.

Windard Haleakala (Hana, Haiku, Makawao):

HIGH SURF ADVISORY IN EFFECT UNTIL NOON HST MONDAY. Mostly cloudy. Scattered showers in the evening, then occasional showers after midnight. Lows around 71 at the shore to around 55 at 5000 feet. East winds 10 to 15 mph. Chance of rain 90 percent.

Leeward Haleakala (Kihei, Wailea, Makena):

Partly sunny. Isolated showers in the morning, then scattered showers in the afternoon. Highs around 90 at the shore to 70 to 77 upcountry. East winds 10 to 15 mph. Chance of rain 50 percent.

Haleakala Summit

Partly sunny. Breezy. Isolated showers in the morning, then scattered showers in the afternoon. Highs around 58 at the visitor center to around 55 at the summit. East winds 15 to 20 mph. Chance of rain 50 percent.

Photo of the Day

Surf Photo of the Day - July 15th, 2017