![National Oceanic and Atmospheric Administration](/build/images/header/noaa.d87e0251.png)
![National Weather Service](/build/images/header/nws.4e6585d8.png)
![United States Department of Commerce](/build/images/header/doc.b38ba91a.png)
Area Forecast Discussion
Issued by NWS Honolulu, HI
Issued by NWS Honolulu, HI
888 FXHW60 PHFO 240142 AFDHFO Area Forecast Discussion National Weather Service Honolulu HI 342 PM HST Sun Jun 23 2024 .SYNOPSIS... High pressure north of the state will maintain breezy trade winds the next few days. Showers will favor windward coasts and slopes. Trades will weaken slightly around the middle of the week, with an uptick in shower activity possible later this week. && .DISCUSSION... Breezy to locally windy trade winds continue this afternoon as a 1031 mb surface high remains approximately 925 miles north of Kauai. Stable conditions also continue as mid-level ridging remains in place to the northwest of the state. Radar and satellite imagery show much drier conditions compared to yesterday with widely scattered weak trade showers moving across the islands. Expect these conditions to continue tonight with showers favoring windward coasts and slopes. The biggest change to the forecast this afternoon has been the issuance of a Wind Advisory for the Big Island Summits. Obs from the Gemini Observatory peaked around 40 mph this afternoon, with guidance showing the potential for gusts over 60 mph possible late tonight into Monday. Expect winds to peak Monday morning before trending downward in the afternoon. Otherwise, the strong surface high will remain to our north through Monday which will maintain our breezy trade wind conditions. A stable and rather typical summertime rainfall pattern will prevail with modest rainfall possible over windward coast and slopes. Aside from some brief afternoon showers over Kona slopes of the Big Island, leeward areas will be mostly dry. Trades look to then weaken slightly on Tuesday as the high to the north weakens, with passing showers over windward coasts and slopes through the middle of the week. Guidance continues to show an uptick in shower activity possible later this week and into the upcoming weekend as an upper-level disturbance develops northeast of the islands. This increased instability combined with bands of moisture embedded in the trade wind flow will certainly boost weekend rain chances as we close out the month of June. && .AVIATION... Breezy to locally windy trades will continue through Monday. Showery cloud bands embedded in the trade flow will produce periods of MVFR conditions across windward/mauka areas of each island, particularly through the overnight and early morning hours each day. Conditions will improve through the late morning and afternoon periods each day. AIRMET Sierra remains in effect for tempo mountain obscuration for windward slopes of most islands, which will likely continue through tonight. AIRMET Tango remains in effect for mod low-level turb over and downwind of island terrain due to the breezy trade winds. This AIRMET will continue through Monday. && .MARINE... Afternoon ASCAT imagery supports dropping the Small Craft Advisory (SCA) for the western half of the area. Otherwise, fresh to strong easterly trades still expected to continue through early this week and the SCA remains in effect for remaining waters through Monday. Trades weaken slightly Tuesday into mid-week. Surf along east-facing shores will remain rough and choppy through Monday followed by a gradual downward trend during mid-week as trades weaken slightly. Expect slightly elevated surf near or slightly below seasonal norms along south facing shores through Tuesday as a small, medium to long period, south swell moves through. The swell has already shown up on the Barbers Point Buoy with energy in the 14-16 second bands. However, this should be short-lived, with a downward trend expected by Tuesday night. Despite a blocking high that has set up over our typical swell window southeast of New Zealand, a gale has formed northeast of this high with the head of the fetch aimed at the islands within the 180 to 200-degree directional band. Given the shorter travel distance, surf associated with this source should trend up late this week. Nearly flat conditions along north facing shores today. A small, medium period, northwest swell will bring tiny surf to north facing shores late Monday through mid week. && .HFO WATCHES/WARNINGS/ADVISORIES... Wind Advisory until 6 PM HST Monday for Big Island Summits. Small Craft Advisory until 6 PM HST Monday for Maui County Leeward Waters-Maalaea Bay-Pailolo Channel-Alenuihaha Channel- Big Island Windward Waters-Big Island Leeward Waters-Big Island Southeast Waters. && $$ DISCUSSION...Ahue AVIATION...Powell MARINE...JVC