Marine Weather and Tide Forecast for Kekaha, HI

SHORT TERM UPDATE
Radar shows numerous light showers moving east to west over most windward and many mauka areas this morning. Skies were mostly cloudy in those same areas, with a few mostly sunny spots in leeward areas. Trade winds will increase today through tonight, leading to additional windward and mauka showers. This is all handled well by the current forecast and no changes are anticipated this morning.

PREV DISCUSSION
Issued at 319 AM HST Tue Jun 23 2026

Looking at current satellite and radar imagery this morning, scattered showers and low clouds are moving across the island chain. Some showers are making it over into leeward areas. These showers are caused by a surface trough moving in from the east.
Expect and increase in showers to continue into Wednesday.

A weak upper level low to our northeast will drift southwest and come near the state Wednesday into Wednesday night before moving off to the northwest and then weakening through Sunday. This upper low will bring cooler air aloft, slightly enhancing instability through the rest of the week. This will lead to a deeper surface boundary and higher inversion height. A slight uptick in rain rates is possible along windward and mauka locations but don't expect widespread heavy or flooding rains.

North of our weak upper level low, an upper level ridge will help keep a strong surface high positioned to our northeast, off the coast of the mainland. This will keep the trades blowing at moderate to occasionally breezy levels into the weekend. Models indicate some drier air approaching Friday and Saturday, reducing the number and strength of showers.

AVIATION
Moderate to locally breezy trade winds expected through midweek.
A trough is moving up the island chain from the east and will continue its trajectory through Wednesday. Expect an increase in SHRA and low cigs causing MVFR conds.

AIRMET Sierra is in effect for mtn obsc across N - SE sections of Oahu, Molokai, Lanai, and Maui. Expect these conditions to continue through today. The AIRMET may be expanded to include Kauai and Big Island later today as well.

MARINE
The subtropical ridge will strengthen north of the islands through Wednesday, increasing trade wind speeds to Small Craft Advisory (SCA) thresholds from Wednesday morning on into the weekend across the windier waters and channels near Maui and the Big Island. A low level trough passing from east to west across Hawaiian Coastal and Offshore waters from Tuesday into Wednesday along with an upper level disturbance will enhance rain shower activity for all waters.

A series of small to moderate, medium to long period south swells will keep surf along south facing shores elevated through the week.
A moderate, medium period south swell will slowly fade through Wednesday. The forerunners of the next long period south swell will begin to arrive in the islands by Wednesday morning, and then build into Wednesday night, peaking on Thursday with head high to overhead surf heights at most exposed south shore surf breaks.

Surf along east facing shores will gradually build through Wednesday and then hold into the weekend as trade winds strengthen. West facing shores will remain on the small side with a slight south swell wrap. Surf heights along north facing shores will remain fairly flat due to the lack of significant north swell energy.

HFO WATCHES/WARNINGS/ADVISORIES
None.