O'ahu residents and visitors should brace for a muggy start to the week, with local forecasts predicting increased shower activity thanks to an influx of deeper moisture over the islands. According to the National Weather Service (NWS) in Honolulu, locally breezy trade winds will continue, bringing sporadic showers that'll hit windward areas the most, and while the Big Island can expect some heavier downpours, the smaller islands will see a less intense increase in windward showers.
Explaining further, NWS officials noted that surface high pressure far to the north-northeast will support "locally gusty trade winds", a state slated to hold steady until possibly easing slightly by the next weekend, concurrently, an area of increased moisture is rolling in from the east bringing cloudy low- and mid-level coverage and a fair bit of wetness, expected to make landfall tonight and persist through tomorrow.
Pilots flying through Hawaiian skies should anticipate moderate to breezy trade winds for the coming days, potentially causing turbulence over and downwind of island terrain, as indicated by an AIRMET Tango in effect. "Clouds and showers will favor windward and mauka areas," according to the NWS's aviation weather guidance, along with a heads-up for temporary mountain obscuration due to low clouds and showers, warranting an AIRMET Sierra through the morning hours and likely to be reissued by evening for certain state regions.
Seafarers aren't left out of this weather advisory—moderate to locally strong trade winds forecasted by the NWS means a Small Craft Advisory is in effect for several water channels and areas around Maui County and the Big Island until early Tuesday morning, with trade winds expected to crank up a notch or two come tomorrow and Tuesday, meanwhile, east-facing shores will see choppy conditions persist, while a new northwest swell might make an appearance by Friday or Saturday as a gale low buzzes along the Aleutian Islands, which could bring a small respite to the flat conditions on north facing shores.
Coinciding with the rest of the weather events are higher-than-expected tide levels, with local gauges registering over a half-foot above predictions—a situation apt to intersect with spring tides and elevate concerns for potential coastal inundation. The NWS has issued a Coastal Flood Statement, currently set to run through Tuesday, with a possibility of extending into Wednesday, as the water levels are predicted to surpass the 1-foot Mean Higher High Water threshold, especially in the afternoons when the tide peaks.
