FXHW60 PHFO 140654 AFDHFO Area Forecast Discussion National Weather Service Honolulu HI 854 PM HST Fri Mar 13 2026 .SYNOPSIS... A powerful kona storm will remain anchored northwest of the state producing periods of hazardous weather impacts across the Hawaiian Islands through the weekend. Expect a combination of threats ranging from significant flash flooding, damaging winds, strong to severe thunderstorms, and snow and ice over the highest Big Island summits. Strong southerly to southwesterly will hold through Saturday and producing damaging wind gusts. The highest threats for damaging winds remain along north and east of the island mountains. Unsettled wet weather conditions with decreasing southwesterly wind trends will continue into early next week. This kona storm begins to lift northward on Monday, and unsettled weather will start to ease across the Hawaii region. High pressure will build back in north of the state during the second half of next week allowing trade winds to gradually return from north to south. && .SHORT TERM UPDATE... Looking into the satellite picture this evening we see the powerful kona storm northwest of the state with rotating upper level troughs enhancing showers and thunderstorms across the Hawaiian Islands. Large bands of heavy showers and thunderstorms will develop rapidly in this unstable weather pattern and may anchor or train over island mountains. Rainfall rates based on available radar and weather observation sites indicate these heavy rain bands are capable of producing 1 to 3 inches per hour. Flash Flood Warnings remain active for most islands this evening with numerous reports of flooding statewide. Strong southerly to southwesterly winds above High Wind Warning thresholds have been reported this evening across the state. These damaging winds will likely continue through early Sunday morning across the state, and linger into Sunday evening for the Big Island. Please postpone travel if possible at least through Saturday as weather conditions will remain a threat to life and property due to the ongoing strong winds, heavy rain, thunderstorm, and flooding impacts from this strong kona storm. && .PREVIOUS DISCUSSION... Issued at 411 PM HST Fri Mar 13 2026 A powerful kona storm continues to strengthen roughly 800 sm northwest of the state. A broad band of showers with embedded thunderstorms is currently draped across the central island chain with Kauai along the western edge of this cloud band. Moderate to locally heavy showers have been persistent across the state with 12 hour rainfall total reaching 5 to 8 inches for some of the wetter locations from Kauai to Maui County. Southerly winds have strengthen to warning levels today with peak gusts up in excess of 60 mph for these islands. Strong winds in excess of 70 mph have been observed at the summits Haleakala and the Big Island thus a High Wind Warning remains in effect across the state. A Winter Storm Warning also remains in effect for Big Island Summits. Forecast remains on track showing the kona low deepening to our northwest allowing for the threat of thunderstorms and severe winds and the potential for severe thunderstorms to continue through tonight as this event peaks into Saturday. The main band of moderate to heavy showers will shift eastward tonight and Saturday before becoming nearly stationary over Maui County and the Big Island. Thus a Flood Watch remains in effect for these areas through Sunday night. Bands of showers and thunderstorms are still forecast to impact Kauai and Oahu into Saturday but the overall trend will be coming down for Kauai early Saturday morning and for Oahu Saturday afternoon. The Flash Flooding threats will continue for Kauai through Saturday afternoon and Oahu through Saturday night due to both saturated soil conditions that more easily lead to ground runoff and flooding from even more moderate continuous rainfall rates. The highest flood threats across the state will favor southern and western slopes. These are typically the drier sides of the islands, less accustomed to heavy rain and flooding. Driving under these heavy shower bands will become challenging with ponding of water on area roadways. Current weather trends in this pattern will change rapidly, these threats to life and property will develop swiftly and can affect any location in the Hawaiian Islands. Postpone outdoor activities or travel if possible until early next week as the kona storm begins to drift northward away from the islands and the threat level across the state diminishes. From Saturday night to Sunday an upper level short wave trough will shift over the state leading to another upward pulse in moderate to heavy shower activity, particularly over Maui County and the Big Island where the main rainband will remain nearly stationary. The threat of thunderstorms will also continue. Monday and Tuesday, the large kona storm begins to weaken and lift northward, slowly drifting away from the Hawaiian Islands. This means wet weather will continue over and near Maui County and the Big Island but should see improvement elsewhere. The extended forecast shows various outcomes during the second half of next week. GFS shows a high pressure system building back into position just north of the island chain as earlier as Wednesday while other deterministic and ensemble models show the high building in Thursday with trades bringing more typical brief passing showers over windward mountain areas. Will continue to monitor latest trends. .AVIATION... Widespread showers, some heavy, along with isolated thunderstorms, will continue into Saturday. Expect widespread MVFR to IFR with local LIFR. Winds will remain primarily out of the south to southwest and increase through the day. Widespread gusts up to and over 35 kt are forecast. There may be a brief break in the rain this evening and overnight, especially for Kauai and Oahu, before showers are expected to become widespread once again during the day Saturday. AIRMET Sierra remains in effect all islands due to mountain obscuration, and Oahu, Molokai, Maui, and Lanai for IFR. This is expected to remain in effect through tonight. AIRMET Tango remains in effect for moderate upper-level turbulence between 130 and FL380. and for low-level turbulence due to strong surface winds. Both of these are expected to remain in effect through Saturday. AIRMET Zulu remains in effect, as high clouds from these showers present icing concerns between FL120 and FL260. This is also expected to continue through Saturday. && .HFO WATCHES/WARNINGS/ADVISORIES... High Wind Warning until 6 AM HST Sunday for Big Island East-Big Island Interior-Big Island North-Big Island South-Big Island Southeast-Central Oahu-East Honolulu-Ewa Plain-Honolulu Metro- Kahoolawe-Kauai East-Kauai Mountains-Kauai North-Kauai South- Kauai Southwest-Kipahulu-Kohala-Kona-Koolau Leeward-Koolau Windward-Lanai Leeward-Lanai Mauka-Lanai South-Lanai Windward- Maui Central Valley North-Maui Central Valley South-Maui Leeward West-Maui Windward West-Molokai Leeward South-Molokai North- Molokai Southeast-Molokai West-Molokai Windward-Niihau-Oahu North Shore-Olomana-South Haleakala-South Maui/Upcountry-Waianae Coast-Waianae Mountains-Windward Haleakala. Flood Watch through Saturday afternoon for Kauai County. Flood Watch through late Saturday night for Oahu. Flood Watch through late Sunday night for Maui County and the Big Island. High Wind Warning until 6 PM HST Sunday for Big Island Summits- Haleakala Summit. Winter Storm Warning until 6 PM HST Saturday for Big Island Summits. Gale Warning until 6 AM HST Saturday for Kauai Channel-Kauai Leeward Waters-Kauai Northwest Waters-Kauai Windward Waters-Oahu Leeward Waters. Gale Warning until 6 AM HST Sunday for Alenuihaha Channel-Big Island Leeward Waters-Big Island Southeast Waters-Big Island Windward Waters-Kaiwi Channel-Maalaea Bay-Maui County Leeward Waters-Maui County Windward Waters-Oahu Windward Waters-Pailolo Channel. && $$ SHORT TERM UPDATE...Bohlin PREVIOUS DISCUSSION...Almanza AVIATION...Parker MARINE...M Ballard