textproduct: Honolulu

SYNOPSIS

Breezy trades will gradually weaken to light to moderate speeds by the latter half of the week. A band of moisture focused over the western end of the state will bring increased shower coverage across the islands of Kauai and Oahu through Monday. Otherwise, periodic showers will filter in on the trade wind flow, mainly focusing over windward and mauka areas. By next weekend, the background flow may become light enough to support land and sea breeze development.

SHORT TERM UPDATE

The overall forecast remains on track this morning, with only a minor update needed to account for a narrow band of moisture focusing showers over the western end of the state. Though the atmosphere is pretty stable, plenty of showers are moving into windward and mauka areas under the strong inversion, with several locations receiving over a tenth of an inch and few over a quarter of an inch in the last 3 to 6 hours across Kauai and Oahu. With the inversion lifted to about 8,000 feet as indicated from this morning's Lihue sounding, several showers are passing over the terrain into leeward areas of Kauai and Oahu, as well.

Based on the upstream open-celled cumulus, scattered to numerous showers will continue to funnel across the western end of the state through Monday, with generally isolated to scattered coverage elsewhere. Whether the focus will be on Oahu, Kauai, or both through the short term will depend on any fluctuations north or south of the axis of the narrow band of moisture caught up in the breezy trade wind flow.

PREV DISCUSSION

Issued at 310 AM HST Sun Jun 7 2026

Radar and satellite imagery shows scattered showers moving over windward and mauka areas with limited spillover into leeward areas across the state this morning. The forecast through the week revolves around gradual fluctuations in trade wind speeds and the timing of minor batches of moisture that will move across the state on the trade wind flow. Guidance remains in good agreement on the surface high to the northeast of the state continuing to drive breezy trades across the state through the rest of today. This high will weaken slightly Monday into Tuesday, then get pushed further northeastward through the rest of the week as a series of lows move across the northern Pacific and a front approaches the region from the northwest. The evolution of the surface high will cause the trades to gradually ease through the week. For the latter half of the week, background winds may be light enough to support land and sea breeze development, bringing afternoon clouds and showers to leeward and interior areas and partial clearing at night.

AVIATION

A high pressure ridge north of the islands will maintain moderate to breezy trade winds for the next couple of days. Clouds and showers being carried in on the trades will bring periods of MVFR conditions primarily to windward and mountain areas, but winds will be strong enough to carry some showers to leeward areas. Otherwise, VFR conditions are expected to prevail.

AIRMET Sierra is in effect for mountain obscuration for windward and mountain areas of Kauai and Oahu due to ongoing and upstream showers. These conditions are expected to be intermittent throughout today, but some clearing is possible this afternoon.

AIRMET Tango is in effect for mechanical turbulence to the lee of the mountains, and that is expected to continue over the next couple of days with little change in the trade wind speeds expected.

MARINE

Surface high pressure will remain anchored far northeast of the islands through early this week. A Small Craft Advisory (SCA), remains in effect for the typical windy waters around Maui and the Big Island. By the middle of this week, a ridge north of the islands associated with the high will be weakened and depressed southward. As a result, trades will drop further and allow the SCA to be cancelled entirely Tuesday or Wednesday.

Small long-period forerunners of the next south swell are starting to show up this morning along our near shore buoys with energy centered in the 18 to 22 second bands. Energy from this swell is expected to peak late Monday into Tuesday and bump up surf to slightly higher than the June average, but still below advisory criteria. Expect this swell to fade through midweek. A smaller pulse of south-southwest swell is due late Thursday and Friday, and a more significant south-southwest swell is on track to arrive next weekend, likely bringing advisory level surf by late Sunday along south facing shores.

Small background energy from the west-northwest is possible over the next several days from a former Typhoon in the West Pacific last week. Rough surf along east-facing shores will remain around seasonal average today, then slowly decline through the midweek as trade winds ease.

HFO WATCHES/WARNINGS/ADVISORIES

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