West Maui : Kāʻanapali South, Maui
Attention: The forecast is not accurate when a tsunami, tropical storm or cyclone watch/warning is in effect. For these events, please seek information for either tsunamis or tropical storms/hurricanes. In case of a possible inundation event, please consult with local authorities and emergency responders to seek further information and direction.
One or more of the following threshold levels is/are shown in the red shaded area in the plot below:
(a) Light Impacts, (b) Hazardous Impacts, (c) Critical Impacts. To better understand their definitions, please check out the Run-up Examples.
The Solid Dark Blue Curve and Solid Cyan Curve display the Past and Forecast Sea Level for the previous 3 days and the next 6 days, respectively, relative to Mean Lower Low Water (MLLW, a typical NOAA datum). Past Sea Level is obtained from a combination of a local tide model with the long-period, non-tidal sea level variability being observed in real-time at Kahului Harbor. Grey vertical lines provide the associated times of high tides.
The Hatched Cyan Curve shows the forecast maximum height (or, run-up height) reached by waves along the shoreline in the Kāʻanapali South region for the next 6 days, relative to MLLW. The run-up height will always exceed or equal the tide plus background sea level described above, because the waves are riding on top of that sea level. The Hatched Dark Blue Curve shows a history of the last forecast run-up height determined for each particular time of the past 3 days; this curve provides context to show how the forecast run-up for the next 6 days differs. For more information on how the forecasts are produced, see the Details tab on the Overview Page.
If the forecast run-up extends into the red shaded region on the plot, the waves are expected to at least become a disruption for beach activities. The higher the forecast the more severe the expected effects. Click on the Run-up Examples tab for descriptions of the possible hazards.
If you would like to receive notifications when the forecast for Kāʻanapali South (or any other West Maui region) reaches the impact stage, please register here:
The south Kāʻanapali region reaches from Puʻu Kekaʻa (Black rock) in the north to Hanakaōʻō Point (north of the Marriott). The region is densely developed with multi-story resorts and condominiums. The medium-to-wide, but seasonally variable, beach is continuous along the length of this region and is generally backed by manicured turf or vegetation. There is strong seasonal variation in beach width due to longshore transport of sand by waves (winter = sand transport toward Hanakaōʻō point; summer = sand transport toward Puʻu Kekaʻa). The region is fronted by a relatively deep fringing reef that provides little or no protection in the north and increasing protection where the reef shallows at the southern end near Hanakaōʻō Point. A shorefront public walkway, resort amenities, and buildings are occasionally threatened by impacts from high waves and erosion during seasonal wave events.
(a) Light Impact – beach and nearshore activities disrupted as occasional waves may sweep the beach slopes or intermittently reach vegetation.
(b) Hazardous Impact – heavy wave action on beach slopes; likely flooding over the entire wide beach; likely run-up to the vegetation and occasional overtopping or undermining of the public walkway at narrow beach locations; and/or noticeable beach sand movement alongshore or offshore/onshore.
(c) Critical Impact – waves regularly sweeping the tops of wide beaches; likely overtopping or undermining of the public walkway where the beach is narrow, with flooding of adjacent land and structures; significant erosion of the beach and manicured turf or vegetation.
(a) Light Impact Event — May 15, 2019 | The Whaler on Kāʻanapali Beach
(a) Light Impact Event — May 21, 2019 | Kāʻanapali Beach
(a) Light Impact Event — June 15, 2019 | The Whaler on Kāʻanapali Beach
(b) Hazardous Impact Event — March 21, 2018 | The Whaler’s Village at Kāʻanapali Beach
(b) Hazardous Impact Event — February 11-12, 2019 | Kāʻanapali Beach
We continue to collect photo documentation to fine-tune the model (if necessary) and to identify the impacts of these run-up events along the West Maui shoreline. We are specifically interested in photos around peak tides or swells, or anytime waves overtop beach features. If possible, capture the maximum extent of water running up the shoreline. The contributions from you, our citizen scientists, greatly contribute to establishing accurate thresholds for the model. Mahalo for your support!
Please submit your photos at:
To view photo submissions, please check out:
An archive of previous forecast plots can be accessed below. Select a day of interest from the calendar, or use the slider tool to quickly navigate through all available images. Two historical forecast plots are provided for each day, generated at 6:00 AM and 6:00 PM of the local time zone. To view the most recent forecast and to learn more about the different components of the graph, please go to the Forecast tab.