textproduct: Honolulu

SYNOPSIS

Moderate to locally breezy trades continue through the forecast period as showers focus primarly windward and mauka.

SHORT TERM UPDATE

High amplitude longwave ridging remains positioned around 170W for the balance of the forecast period, strengthening to an impressive 599dm this weekend. This will in turn favor persistence of extensive high pressure at the surface and breezy trades well into next week. Around this high, a much drier and more stable mid-level airmass will advect into the area during Wednesday ensuring increasingly high stability during this time. Dewpoints will likewise dip toward the upper 60s to 70 degrees by Wednesday evening taking the edge off of recent muggy weather. An enhanced but shallow moisture field associated with benign troughing from a long-since dissipated tropical system will be on the doorstep in about a week and may bring an uptick in showers for windward and mauka zones.

PREV DISCUSSION

Issued at 413 PM HST Mon Aug 24 2026 Latest radar and satellite imagery shows warming cloud tops and decreasing rain rates over the Kona slopes of the Big Island. Thus, the Flood Watch over the Big Island has been cancelled.

While the threat for heavy rain has ended over the Big Island, humid conditions will still persist across the state through tonight due to the higher than normal dewpoint temperatures. Drier air should gradually move in on Tuesday, which should help bring some relief of the humid conditions.

For Tuesday, we are looking at a fairly dry day across the state with breezy trade winds. The one exception will be over the Kona slopes of the Big Island, where they should see afternoon clouds and showers develop. Some brief periods of moderate rain will be possible due to some lingering moisture.

By Wednesday, we should be back to our typical summer time trade wind weather with breezy trades, dewpoints in the 60s and a few passing showers over windward and mauka areas. This typical summer time trade wind weather will likely persist through rest of the week with brief increases of showers from time to time. Trade winds will also likely ease slightly and become more moderate to locally breezy speeds by the end of the week.

AVIATION

Moderate trades expected through the period. Low cigs and SHRA possible over windward and mauka slopes. MVFR conds in heavier SHRA otherwise VFR prevails.

AIRMET Sierra is in effect for mtn obsc for windward locations of Kauai, Oahu and Maui. Conds expected to improve in the mid morning hours.

AIRMET Tango is in effect for mod low-level turb lee of terrain and may be needed for a few days.

MARINE

Issued at 413 PM HST Mon Aug 24 2026 Fresh to locally strong trades will persists as Tropical Depression Moke passes far southwest of the island chain and broad high pressure remains north of the state. Convection associated with this system will remain over the far southern portion of the offshore waters as it tracks west. Maui Leeward Waters has been removed from the Small Craft Advisory and now only includes the typical windy waters around Maui County and the Big Island.

Surf along east facing shores will remain rough and choppy due to persistent trade wind swell.

Surf along south facing shores will remain below summer average as a small medium period south swell slowly fades through Tuesday. An overlapping small, long period south southwest swell will fill in tonight through Tuesday that should keep surf below the summer average. A slightly larger long period south swell will fill in Wednesday and peak Thursday into Friday. This swell could push surf towards advisory thresholds before slowly fading over the weekend.

Surf along north facing shores will remain tiny.

FIRE WEATHER

Issued at 701 PM HST Mon Aug 24 2026

It is not anticipated that the critical fire weather threshold will be reached during the forecast period owing to elevated dewpoints and winds remaining below criteria. KBDI likewise remains a bit low due to recent rainfall. Day to day variability during the next week will be modest as the governing pattern remains rather stagnant.

HFO WATCHES/WARNINGS/ADVISORIES

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