0-2 foot
0-2 foot
0-2 foot
0-2 foot

Light to moderate trade winds are expected to continue today, with winds remaining below Small Craft Advisory thresholds. A weak trough of low pressure will pass through the islands today and tonight, bringing the potential for some heavier showers and thunderstorms. Following the passage of the weak trough, high pressure will build well northeast of the state through the middle of next week, while Hurricane Hector is forecast to pass by to the south of the Big Island on Wednesday. As a result, we should see a strengthening of the pressure gradient across the islands tonight and Sunday, with SCA conditions likely returning to the typically windy waters around Maui and the Big Island. Moderate to strong trade winds are then expected to continue Sunday night through the middle of next week, and SCA conditions may expand to other marine zones. It is still too early to determine the exact impacts that Hurricane Lane may have on the coastal waters, so mariners are urged to keep up to date with the latest forecasts.

No significant swells are expected through the weekend, so expect surf to remain small on all shores. A small, north-northwest swell is expected to arrive on Monday and continue through Tuesday. A larger north swell is expected to arrive late Tuesday, peak Tuesday night and early Wednesday, then slowly fade through Thursday. We will continue to monitor the track and intensity of Hurricane Lane as it moves closer to the islands, as an elevated easterly swell is expected to move into the coastal waters beginning Sunday night and continuing through the middle of next week. This easterly swell will likely result in large surf for east and southeast facing shores of the Big Island and could potentially produce large surf for east facing shores of Maui.

Hawaii Wave Height Model

Tide Predictions

Low tide at Kahului was 0.45 foot at 2:00 PM early this afternoon, rising to a high of 1.72 foot at 2:00 PM early this afternoon.

The sunrise was at 06:05 am this morning and will set at 06:53 pm this evening. The Moon is currently 8 days old, and is in a Quarter phase. The next Waxing Gibbous will occur at 11:58 AM on Sunday, August 26th.

Hawaii Wind Report

Maui Weather

°/°
Wind: n/a at 0 mph
Sunrise:
Sunset:
current observations as of 4am September 26th, 2018

Weather Outlook for Saturday, 18th August 2018

Summary

Light to moderate trade winds will continue through the day today, then begin to increase into the moderate to breezy category by Sunday as a weak trough of low pressure moves through from east to west. Humid and unsettled conditions associated with this trough will translate to increasing rainfall chances and potentially a few thunderstorms. Breezy and drier trade wind conditions are expected to fill in Sunday night through the early portion of next week. Although it is too early to determine how the islands will be impacted, Hurricane Lane is forecast to track through the region near the islands through the middle part of next week.

Detailed Discussion

Short-term (through Sunday night) guidance remains in good agreement and is initializing well with the current pattern and trends. Consensus supports increasing moisture and rain chances across the state as a weak surface trough moves through from east to west. The latest surface analysis and satellite imagery showed this feature approaching the Big Island tracking toward the west within the trades. Earlier satellite-derived precipitable water (PW) imagery depicted a large area of higher moisture associated with it with values at and above 2″. Expect humidity levels to climb as mid 70 dewpoints fill in.

Provided light to moderate trades in place, the bulk of the shower activity will focus over windward and mauka locations, with the exception being over the typical leeward locations such as the Big Island through the afternoon hours (due to peak heating/sea breezes). In addition to the increasing moisture and rainfall chances expected, a few thunderstorms will remain possible, especially through the afternoon hours. Recent upper air soundings at Hilo support this potential with modest mid-level lapse rates/no inversion and increasing PWs. Confidence, however, remains low, mainly due a mid- to upper-level ridge that guidance is depicting nosing westward over the state through the day today.

The extended (Monday through Thursday) guidance remains in decent agreement and supports a drier and more stable trade wind pattern returning Monday through Tuesday. Trades will likely climb into the breezy category due to a strengthening pressure gradient between high pressure to the north and Hurricane Lane approaching the region from the east-southeast. Forecast uncertainty ramps up heading into the middle/latter half of next week as Hurricane Lane passes near or just south of the islands. It remains too early to forecast the exact location of Lane and whether it will directly impact portions the state. Forecast confidence will steadily rise through the weekend into early next week.

Central Valley (Kahului, Spreckelsville):

Mostly cloudy with scattered showers. Locally heavy rainfall possible. Lows 69 to 75. Northeast winds up to 15 mph. Chance of rain 50 percent.

Leeward West (Lahaina, Ka`anapali):

Mostly cloudy with scattered showers. Locally heavy rainfall possible. Lows 70 to 77. East winds up to 15 mph. Chance of rain 50 percent.

Windward West (Wailuku, Waiehu):

Mostly cloudy. Frequent showers in the evening, then numerous showers after midnight. Locally heavy rainfall possible. Lows 62 to 74. Northeast winds 10 to 15 mph decreasing to up to 10 mph after midnight. Chance of rain 90 percent.

Windard Haleakala (Hana, Haiku, Makawao):

Mostly cloudy. Numerous showers in the evening, then frequent showers after midnight. Locally heavy rainfall possible. Lows around 72 at the shore to around 56 at 5000 feet. East winds up to 15 mph shifting to the southeast after midnight. Chance of rain 90 percent.

Leeward Haleakala (Kihei, Wailea, Makena):

Mostly cloudy in the evening then becoming partly cloudy. Scattered showers. Locally heavy rainfall possible. Lows around 72 at the shore to 55 to 61 upcountry. East winds up to 15 mph. Chance of rain 50 percent.

Haleakala Summit

Mostly cloudy. Breezy. Scattered showers in the evening, then isolated showers after midnight. Locally heavy rainfall possible. Lows around 49 at the visitor center to around 46 at the summit. East winds 15 to 20 mph. Chance of rain 50 percent.