textproduct: Honolulu

SHORT TERM UPDATE

No major changes this morning. Tropical Depression Moke continues to pass well south of the Hawaiian Islands this morning. Flood Watch still remains in effect for the Big Island through this afternoon. Latest RRFS model shows the heaviest precipitation over the leeward slopes of the Big Island this afternoon with a few inches of rain possible. Meanwhile on the windward side, scattered showers are expected, but no significant rainfall is expected. The threat for flash flooding should diminish by this evening.

PREV DISCUSSION

Issued at 309 AM HST Mon Aug 24 2026

Radar and satellite imagery shows scattered showers moving across the state. While mostly impacting windward and mauka spots some showers are making over into leeward locations. Moke is south- southwest of the Big Island with deep moisture sheared to the north of the system that is mostly skirting south of Big Island. This has kept rainfall on the lighter side with no flash flooding threats overnight. However, a flood threat will continue through this afternoon. As Moke continues to move westward, low- to mid- level flow on the Big Island will veer out of the east to the east- southeast, which could optimize orographic lift and increase rainfall on southeast slopes. Afternoon showers could produce localized flooding across the Kona Districts. As such the Flood Watch will be continued through this afternoon for the Big Island. Trades are slowly decreasing as Moke continue to move away from the state allowing the pressure gradient to relax.

On Tuesday and through the rest of the week, a trade wind pattern will return. Trades should be at moderate strength with typical windward and mauka showers occurring.

AVIATION

Lingering moisture in the wake of Moke will support a bit more widespread than normal windward to mountain showers through at least this afternoon with MVFR conds possible in showers. There is a slight chance of a thunderstorm over the Big Island afternoon, but will unlikely impact the airports. Moderate to locally strong trade winds will continue into at least Tuesday.

AIRMET Tango is in effect for low level turbulence downwind of terrain due to the strengthened trade winds. AIRMET Sierra is in effect for mountain obscurations over windward portion of the islands except for the Big Island.

MARINE

Fresh to locally strong trades 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. A Small Craft Advisory remains in effect for most waters around Maui 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 elevated as a small medium period south swell slowly fades today. An overlapping long period south southwest swell is expected to slowly fill in tonight through Tuesday that should provide a slight boost in surf. A slightly larger south swell will fill in Wednesday and peak Thursday. This swell could push surf towards advisory thresholds.

A small, medium period west northwest swell originating from Tropical Storm Lala will fade during the next 24 hours.

FIRE WEATHER

Issued at 309 AM HST Mon Aug 24 2026

Winds are slowly declining and will fall into the moderate category on Tuesday. Humidity remains higher than normal due to moisture on the northern periphery of Tropical Depression Moke brushing the state. Heavy rain is possible this afternoon on the southeast slopes of the Big Island and in the Kona Districts, while lower rainfall totals are expected over other windward areas of the state. A more typical summertime trade wind pattern will return by Tuesday.

HFO WATCHES/WARNINGS/ADVISORIES

Flood Watch until 6 PM HST this evening for Big Island East-Big Island Interior-Big Island North-Big Island South-Big Island Southeast-Big Island Summits-Kohala-Kona.

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