textproduct: Honolulu

SYNOPSIS

A plume of moisture will move over the state from southeast to northwest through Wednesday. Moderate to occasionally heavy showers will continue over the eastern end of the state into tonight, before focus shifts westward on Wednesday. Windward and mauka areas could see minor flooding, similar to what windward Big Island experienced today. A more typical (drier but not dry) trade wind pattern will return late Wednesday and continue into early next week.

SHORT TERM UPDATE

Issued at 825 PM HST Tue Jun 2 2026

This evening, showers continue across portions of the Big Island as a plume of moisture remains over the state. However, the intensity and coverage of these showers has significantly decreased over the past few hours, and that trend is expected to continue into tonight. Therefore, no Flood Advisories remain in effect. Elsewhere, scattered showers also linger over Oahu and, to a lesser degree, Kauai as well. As the previous discussion mentioned, the focus for enhanced shower coverage is expected to shift to the western islands on Wednesday, followed by drier conditions statewide by Wednesday evening as the plume of moisture moves west of the region.

PREV DISCUSSION

Issued at 335 PM HST Tue Jun 2 2026

Radar and satellite show numerous showers and cloudy skies over Big Island, with scattered showers and mostly cloudy skies for Maui County. West of there, isolated showers and partly cloudy skies prevailed. Trade winds averaging 10 to 20 mph with gusts near 30 mph were mainly out of the northeast.

A significant moist plume was moving over the state this afternoon. This has helped bring substantial rainfall to the eastern coastal region on Big Island, where a Flood Advisory remains in effect. As this moisture moves west through the state tonight and then exits Wednesday evening, moderate rainfall will continue within areas of showers. These areas will move fairly quickly, so the main threat for any minor flooding will be windward and mauka. The chance of rain has been increased for tonight and Wednesday in this latest forecast.

Thursday, trades will increase and then remain moderate to breezy through the weekend and into next week. A weak ridge aloft to our northeast will weaken over the next few days, and a new stronger closed upper ridge will develop to our north this weekend. This will help keep a strong surface high to our north, ensuring the trades continue. Models indicate smaller pockets of moisture within this trade flow, but it will be difficult to time their arrival until they are just a day or two away (due to model error). Therefore, periods of showers will continue, with some days wetter than others, and overall slightly wetter than normal for June. However, the risk for any significant flooding will remain low from Thursday well into next week.

AVIATION

Issued at 825 PM HST Tue Jun 2 2026

A surface trough near the islands will continue enhance showers into tonight, shifting west to Kauai Wednesday morning. MVFR conditions are possible within these showers. Moderate to breezy trade winds are forecast to return Wednesday as the atmosphere begins to stabilize.

Airmet SIERRA for mountain obscuration is in effect for windward Kauai and all of Oahu, Maui, Molokai, Lanai, and the Big Island. These conditions should begin to wane through the overnight hours, with relief expected across all islands by late Wednesday morning.

AIRMET Tango remains in effect for moderate turbulence below 8000 feet all areas of the state.

MARINE

Issued at 335 PM HST Tue Jun 2 2026

Fresh to strong easterly trades will slightly strengthen through the second half of the week as the subtropical ridge strengthens north of the islands. Small Craft Advisory remains in effect across the typically windier channels and waters around Maui County and the Big Island. Additional marine zones, may need to be added to the advisory in subsequent packages as the area of strong winds expands. Guidance suggests this pattern will persist through the weekend.

Surf along exposed south-facing shores will continue to gradually rise through tonight as a fresh long-period south-southwest swell continues to fills in. Offshore buoys continue to show a rising trend centered near the 17-second band. This swell will likely peak late tonight into Wednesday just below the warning level threshold of 15 feet faces. Thereafter, a gradual downward trend is expected through the latter half of the week. A High Surf Advisory remains in effect for south facing shores through early Thursday morning. Surf may linger around advisory thresholds during the day Thursday but will likely drop below advisory thresholds by Friday.

Surf along north-facing shores will continue increasing through the second half of the week as a couple of out-of-season northerly swells arrive from a broad low pressure centered far north of the state near the Aleutian Islands. Surf heights will likely rise above the seasonal average by Wednesday, then remain elevated through Thursday and Friday before gradually easing over the weekend.

Surf along east-facing shores will gradually build through the week as strengthening trade winds generate increasing short- period wind waves. Surf should return to near seasonal levels by the end of the week.

HFO WATCHES/WARNINGS/ADVISORIES

High Surf Advisory until 6 AM HST Thursday for Big Island South- Big Island Southeast-East Honolulu-Ewa Plain-Honolulu Metro- Kahoolawe-Kauai South-Kauai Southwest-Kona-Lanai Leeward-Lanai South-Maui Central Valley South-Maui Leeward West-Molokai Leeward South-Niihau-South Haleakala-South Maui/Upcountry- Waianae Coast.

Small Craft Advisory until 6 AM HST Thursday for Alenuihaha Channel-Big Island Leeward Waters-Big Island Southeast Waters- Maalaea Bay-Pailolo Channel.