textproduct: Honolulu

SYNOPSIS

Moderate to locally breezy trade winds will continue through the next few days with a gradual strengthening expected Thursday into Friday. Mostly dry conditions will continue to persist through Friday with some some passing showers over windward and mauka areas. As we head into the weekend, the main weather concern will be related to the tropical cyclone development of 93C, currently over 1000 miles east-southeast of the state. Residents and visitors should prepare now for potential tropical cyclone impacts this weekend. For the latest development regarding 93C, please check out www.hurricanes.gov.

SHORT TERM UPDATE

Issued at 830 PM HST Tue Aug 11 2026

No major forecast updates this evening, as things remain on track. Latest satellite imagery does show a few more clouds moving into windward sections of Molokai, Maui, and the Big Island this evening, but very little shower activity is noted on radar or in surface observations. As the previous forecast indicated, the main focus for the rest of the week will be potential tropical development later this week.

PREV DISCUSSION

Issued at 414 PM HST Tue Aug 11 2026

Satellite imagery this afternoon continues to show a dry summertime weather regime with a few showers over windward areas and the kona slopes of the Big Island. 00Z Hilo and Lihue soundings show a strong inversion at around 4500-5000 feet, which is about 1000 feet lower than normal and in line with the drier conditions. Mostly dry conditions are expected to continue through Friday with a few scattered showers riding in with the trade winds from time to time.

The main concern over the next 7 days will be related to the area of potential tropical development currently over 1000 miles east- southeast of the state. The National Hurricane Center (NHC) continues to report that the area is conducive for tropical development with a 90 percent chance of development over the next 48 hours. While confidence is fairly high for the state to be impacted by a tropical cyclone this weekend, the severeness of the impacts remain very uncertain due to lack of formation as of Tuesday afternoon. Once the system becomes better organized, we should have higher confidence in the weather impacts. But until then, here is a list of potential hazards that we could see this weekend.

FIRE WEATHER... Fire weather concerns increase on Friday. Winds will begin to strengthen and a dry and stable air mass with low relative humidity in advance of the storm will likely lead to high wildfire potential.

STRONG AND GUSTY WINDS... Winds could strengthen further on Saturday, though the timing, direction, and magnitude of the strongest winds remain highly dependent on the eventual track and intensity of the system. Even if the center of the system remains away from the islands, the north semicircle of the storm will likely produce damaging winds.

HEAVY RAINFALL... This system could bring periods of heavy rainfall, particularly across east and southeast-facing slopes. Orographic enhancement could result in locally higher rainfall totals where moist tropical flow interacts with island terrain. If heavier rainfall persists over the same locations, flash flooding and rapidly rising streams are possible.

LARGE AND ROUGH SURF... The developing system is expected to generate a large easterly swell as it moves northwestward across the Central Pacific. Surf may build along east-facing shores from east to west as the system approaches, with Warning-level surf of 15 feet or larger possible into the weekend.

AVIATION

Issued at 414 PM HST Tue Aug 11 2026

Moderate to breezy trade winds are likely to remain in place through most of the week. Showers will focus over mostly windward and mountain areas, and remain light due to an area of drier air anticipated to move through the islands tonight through tomorrow.

No AIRMETs are in effect and none are anticipated.

MARINE

Issued at 414 PM HST Tue Aug 11 2026

High pressure to the far northeast will slowly drift into position north of the Hawaiian Islands into the weekend, producing moderate to locally strong trade winds across the region. A Small Craft Advisory (SCA) remains in effect through Wednesday afternoon for the windier waters and channels around Maui and the Big Island. The weather pattern may change significantly this weekend as we continue to watch for a developing tropical cyclone currently in an area roughly 950 NM east-southeast of the Hawaiian Islands. Potential impacts are uncertain at this time, as the tropical cyclone has not yet formed and track guidance remains highly uncertain at this time. Marine interests should be prepared in case this system potentially turns towards the Hawaiian Islands after formation potentially as early as this weekend.

Surf along south and west facing shores will continue to remain elevated as overlapping south swells continue to fill in around the islands through tonight. A moderate, long period south swell will fill in Wednesday peaking near or slightly above advisory levels late Wednesday into Thursday before slowly fading through the rest of the week.

Surf along east facing shores will continue to remain moderate and rough due to continued trade winds. Later in the week, the track of a developing tropical cyclone will dictate the potential for a large swell exceeding warning levels from the east to southeast direction.

Surf along north facing shores will remain flat to tiny through the week.

Due to a combination of peak monthly high tides and water levels running higher than predicted in a few locations, a Coastal Flood Statement remains in effect for minor coastal flooding around the afternoon high tide through Wednesday. Tides will be decreasing by the end of this week, but coastal flooding may continue to be possible around high tide for locations where water levels are running highest.

FIRE WEATHER

Issued at 414 PM HST Tue Aug 11 2026

High pressure to the northeast of the state will maintain moderate to locally breezy trades over the next few days. A pocket of drier air is expected to move in on Wednesday, which will bring afternoon humidities down to near critical thresholds Wednesday afternoon, although winds will remain moderate to locally breezy. Fire weather concerns could increase further on Friday as the trade winds strengthen to strong speeds. The combination of dry weather and breezy to locally strong trade winds will create near- critical fire weather conditions on Friday. Temperature inversion heights will range between 4,500 to 6,000 feet over the next few days.

HFO WATCHES/WARNINGS/ADVISORIES

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