Honolulu is preparing for more bad weather as the National Weather Service warns of heavy showers and thunderstorms, especially in the western parts of the state. An upper-level disturbance is causing unstable conditions, which could last through today. Expect continuous rainfall in windward, mauka, interior, and leeward areas, driven by light to moderate east-southeast winds and sea breezes, according to the National Weather Service.
The overnight deluge has particularly affected Oahu's windward side, where "3 to 5 inches of rain were observed within a six-hour period," prompting stream levels to soar to flood stage, and leading to the issuance of a Flood Watch, as reported by the National Weather Service. This warning, which extends until this afternoon, covers Niihau, Kauai, and Oahu. Despite the potential for localized heavy showers and storms to develop and linger, forecasters anticipate a gradual lessening of widespread heavy rainfall as the night progresses.
A gradual transition back to moderate to breezy easterly trade winds is expected later tonight, extending into Tuesday. A forecast from the National Weather Service indicates this shift in wind patterns should bring a semblance of normalcy, with showers starting to favor typical windward areas through the remainder of the week. As the week progresses, stability should increase as upper-level conditions improve and the convergence zone moves north.
Light to moderate east-southeast winds, along with possible showers and thunderstorms, may reduce visibility in some areas, while others will stay clear. Mariners are facing rough waters due to a low-pressure system. An AIRMET Sierra has been issued for Oahu and the windward parts of other islands because of mountain obscuration. Small Craft Advisories are expected later this week due to stronger winds and rough seas, according to the National Weather Service.
A small north-northwest swell will peak today and decrease by Tuesday, bringing a slight increase in surf to north and some west-facing shores. Over the next week, small to moderate swells will keep the surf up on northern and western shores, with a bigger swell possibly arriving next weekend. East-facing shores will have choppy surf early in the week, with conditions improving by midweek, as per the National Weather Service.
