Moderate to locally breezy north-northeast to northeast trade winds will strengthen this afternoon and evening and become gusty over leeward areas. A weakening trough passing through the state this morning will produce scattered showers over windward and mauka areas with brief downpours possible. A drier airmass will filter over the western half of the state this afternoon, while showery conditions could persist over the windward areas of the eastern half of the state through tonight. Drier, cooler air will fill in state wide by Sunday with scattered showers returning at the start of the work week.
Issued at 400 AM HST Sat Mar 28 2026
This morning’s satellite imagery shows a weak trough making its way through the state from the north, which is producing scattered showers across most windward areas of the state with frequent showers over the windward areas of Maui. For the day today, we should see scattered showers persist over windward and mountain areas throughout the morning with a gradual decrease of shower coverage throughout the day especially over the western half of the state as a drier air mass moves in behind the passing trough this morning. Over the eastern half of the state, showers will likely persist through much of the day with a gradual decrease expected over Maui later this afternoon and over the Big Island later tonight.
High pressure building far north of the state should gradually strengthen our north-northeast to northeast trade winds this afternoon and evening with gusty winds expected over leeward areas. 12Z soundings from Lihue and Hilo show the inversion at roughly 6000-7000 ft this morning. But as the drier airmass fills in this afternoon, we should see the inversion lower and the combination of the strengthening trade winds and lowering inversion, should allow for wind gusts of 40 mph over select leeward areas. While the latest REFS model showed decent probabilities of 40 mph winds over leeward areas this evening and tonight, the probabilities of 50 mph winds were very low. Thus, elected not to issue a Wind Advisory for leeward areas for the time being. Winds will be closely monitored throughout the day today to see if winds reach Wind Advisory thresholds.
Sunday looks to be a windy, but fair weather day with mostly dry conditions. Some scattered showers will be possible over windward Big Island especially in the morning hours.
For the first half of next week, a cold upper level low will develop northeast of the state. While temperatures aloft will be cold and unstable, we will continue to remain on the dry side of the upper level low. While heavy showers are not expected, we should see scattered showers moving in with the trade winds especially over windward and mauka areas. Trade winds will gradually decrease throughout the first half of next week as the high weakens to our north. Trade winds should lower to moderate speeds towards the second half of next week.
Issued at 400 AM HST Sat Mar 28 2026
A band of showers and attendant MVFR conditions will impact Windward Maui early this morning before spreading to the Big Island later in the day today. Moderate NNE trades will continue to prevail, strengthening by the afternoon in response to deepening low pressure northeast of the state. Winds are expected to abate slightly overnight heading into Sunday.
AIRMET Sierra for mountain obscuration remains in effect for windward Molokai and Maui. This is expected to continue through at least the early morning today, with conditions potentially spreading to the Big Island by the afternoon.
Issued at 400 AM HST Sat Mar 28 2026
A gale force low northeast of the islands will interact with high pressure building in from the northwest to strengthen the northeasterly trade winds to fresh to strong speeds today. The current Small Craft Advisory (SCA) covering the leeward waters and channels around the smaller islands will expand to encompass the waters around the Big Island this morning as the stronger winds progress down the island chain. The SCA has been extended through Sunday evening, but will likely need to be expanded to all coastal marine zones on Sunday as seas of 10 ft or greater generated by the gale force low begin to move into the area. SCA conditions will likely continue at least through the first half of the week for at least some portion of the coastal waters.
Surf will decrease slightly along north-facing shores through the day today as a small medium- period northwest swell fades. A short-period northeast swell will continue to bring slightly below average surf to east-facing shores, though as trade winds strengthen today, surf heights will build slightly along east- facing shores.
Another small bump in the northwest swell arriving Sunday night will be overshadowed by a much larger medium-period north- northeast swell on Sunday. Surf will quickly build through the day for north- and east-facing shores. High Surf Advisory (HSA) conditions appear likely to develop sometime on Sunday, with the swell peaking late Sunday and holding through Monday, before fading gradually through the rest of the week. HSA conditions may also be possible for west- facing shores of the Big Island, particularly near Kua Bay, as the north-northeasterly swell works in through the gap between Maui and the Big Island. Some shores of west Maui also see elevated surf from this swell, but it is not currently expected to meet HSA criteria.
Along south-facing shores, small background pulses will keep surf heights above flat conditions through early next week, with a slight bump possible as one of these pulses arrives today.
Small Craft Advisory until 6 PM HST Sunday for Alenuihaha Channel-Kaiwi Channel-Kauai Channel-Kauai Leeward Waters-Kauai Northwest Waters-Maalaea Bay-Maui County Leeward Waters-Oahu Leeward Waters-Pailolo Channel.
Small Craft Advisory until 6 PM HST Sunday for Big Island Leeward Waters-Big Island Southeast Waters-Big Island Windward Waters.
