Marine Weather and Tide Forecast for Heeia, HI

DISCUSSION
Satellite showed mostly cloudy skies over Kauai County and the Big Island this morning, and partly cloudy skies elsewhere. Radar indicated isolated showers over Kauai County, with a larger area of showers to their south and west. Winds were generally out of the east at 5 to 10 mph.

A weak upper level low just to the east of the Big Island will weaken further and then move off to the northeast over the next few days. This will have virtually no impact at the surface, apart from some shade from increased cloudiness. Trade winds will continue to build back in - initially from the east, then becoming northeast and strengthening late this coming week.

Winds are expected to be light enough for sea-breezes to develop in some areas again today, leading to an increased chance of showers in leeward areas. This was already in the forecast, and was maintained.

We will see an increase in the chance of showers Monday night into Tuesday as an area of enhanced moisture moves in from the east. This moisture will be most pronounced near the Big Island, but will impact the windward areas of all islands. Some adjustments were previously made to account for this, and we have further increased the chance of rain during this period in this morning's forecast as confidence increases.

AVIATION
Light to moderate trades through the period. Low cigs and SHRA should primarily impact windward and mauka locations with some isol SHRA over leeward areas. MVFR conds possible in SHRA, otherwise VFR prevails.

AIRMET Sierra is in effect for mtn obsc for portions of all islands. Conds should improve in the mid morning hours.

MARINE
Moderate to fresh trade winds continue this weekend, though weaker winds will remain in place over the western waters as a trough lingers west of the area. Trade winds then decrease this upcoming week into the light to moderate range through much of the week with slight day to day fluctuations. Strengthening trades are possible towards the end of the week as high pressure builds north of the area.

A long-period south swell will peak today and hold through Monday, producing elevated surf along south and west-facing shores, but it will remain below advisory levels. South shore surf will decline gradually Tuesday into Wednesday, but a new long-period south swell arriving late Wednesday will provide another bump in surf for Thursday and Friday.

The short-period north-northwest swell generated by low pressure to the northwest of the islands will fade today, while a new small, long-period swell peaks. This will keep small surf continuing today for north-facing shores, but surf declines on Monday as this swell fades. Another small, long-period northwest swell is forecast to arrive on Monday and peak Tuesday, which will boost north shore surf back to moderate levels. A moderate north- northwest swell is possible by the end of the week, depending on the evolution of a projected low in the north Pacific. However, confidence is low given differences in model solutions with this feature.

Surf along east-facing shores will remain small as local winds remain fairly weak with only slight variations each day. Small, moderate-period west and east swells generated by multiple Pacific tropical cyclones continue to move through the islands through Monday.

FIRE WEATHER
Light to moderate trades will be with us into the middle of the coming week. Moisture will decrease today through Monday, bringing RH values down to near critical values on parts of the Big Island Monday, including near Kona. However, winds will too light for any fire weather headlines. Inversion heights are around 5500-6500 feet across the eastern end of the state.

HFO WATCHES/WARNINGS/ADVISORIES
None.