textproduct: Honolulu

SYNOPSIS

A weak surface trough that brought areas of showers to much of the state the past few days has finally moved west of Kauai. Trade winds will now become fully established and continue through the upcoming week. We will see showers favoring windward and mauka areas, most frequently at night and during the early morning hours. Overall, the next week will be drier for most folks than this past week.

DISCUSSION

A surface trough which brought areas of showers, some briefly moderate to heavy, has moved just west of Kauai this afternoon. The state will see drier conditions for the remainder of this afternoon, and for most of the coming week. Radar this afternoon shows just a few showers in the Kona region on Big Island, with isolated windward showers elsewhere. In addition to lower clouds associated with showers, satellite showed thin high clouds continuing to stream over the region from the west-southwest.

At upper levels, a ridge north of the islands, spread across much of the Pacific south of 35 deg N, will dominate our weather for the upcoming week. A minor weakness in the ridge may develop late in the week, but guidance is in agreement that it won't be enough to weaken the associated surface ridge significantly. Therefore, trades will continue for the foreseeable future. We will experience a typical trade wind pattern, with showers mainly windward and mauka, and most frequent at night. Wind speeds are forecast to be moderate to breezy, strong enough to be concerning for boaters, but probably not strong enough for wind advisories on land.

AVIATION

Stable and mostly dry trade wind weather is expected through Monday with trades increasing a bit more on Monday with widespread breezy trades expected by Monday afternoon. Isolated to scattered showers will continue to ride in with the trade winds especially over Kauai and other windward areas, particularly during the overnight and morning periods, which could produce brief MVFR conditions. Otherwise VFR conditions should prevail at area terminals.

AIRMET Sierra is in effect for mtn obsc over Kauai N through E sections due to some lingering moisture in the area.

AIRMET Tango is also in effect for low-level turb due to the breezy trades.

MARINE

High pressure remains in place north of the Hawaiian Islands this week in maintenance of fresh to locally strong trades continuing into next weekend. The Small Craft Advisory remains in effect.

A small medium period NW swell maintains small surf along N and W shores today. A new slightly larger N swell arrives late tonight peaking during Monday. Another small long period NW swell arrives Wednesday afternoon and peaks early Thursday.

Small long period S swell has faded through today. However, two additional small long period S swells arrive Monday and Thursday. Surf along E shores remains below normal in the near term, with increasing surf peaking by Wednesday as trade winds strengthen.

HFO WATCHES/WARNINGS/ADVISORIES

Small Craft Advisory until 6 AM HST Tuesday for Alenuihaha Channel-Big Island Leeward Waters-Big Island Southeast Waters- Maalaea Bay-Pailolo Channel.