textproduct: Honolulu

SYNOPSIS

Trade winds will taper off through much of this week as remnants of Tropical Cyclone Genevieve linger between the high and Hawaii. Clouds and showers will favor windward and mauka areas, with some enhancement possible for the western half Tuesday through Thursday due to an upper trough setting up to the west.

DISCUSSION

Satellite and radar imagery shows showers and low clouds moving on the trades. Most of the showers are impacting windward and mauka locations. Wind speeds will decline to gentle to moderate through much of the week as remnants of former Tropical Cyclone Genevieve linger between Hawaii and the high pressure system. It is not expected to impact Hawaii aside from the decrease in wind speeds.

Model guidance continues to show an upper level trough near the western end of the state Tuesday through Thursday, which may provide some enhancement of incoming trade wind clouds and showers. This feature will move north away from the area on Friday. Models are hinting at some incoming tropical moisture along a trough connected to the ITCZ. Trades will push this area of moisture across Big Island and Maui.

AVIATION

Generally VFR with weaker trade winds. Occasional MVFR ceilings and visibilities within more organized showers focused over windward and upslope mauka exposures. No AIRMETs currently in effect and none expected this period.

MARINE

A ridge of high pressure north of the state will continue to weaken over the next several days as a front passes far north of the state. Trade wind speeds will weaken in response, lasting through Thursday. Trade winds should restrengthen by the end of the week as high pressure builds far north of the state. The Small Craft Advisory was cancelled this morning.

Surf along south facing shores will stay below seasonal averages with mainly background energy throughout most of this week. The next small, long period south swell will arrive by Saturday with a slight bump in south shore surf heights through Sunday. A series of south swells are expected the following week (week of Aug 9th), which should produce surf heights at or above seasonal averages.

East facing shores will remain rough and choppy with steady decreasing trends as the trade winds ease through much of the week. Small, medium period easterly swell generated from former Tropical Cyclone Genevieve will linger over the next few days.

Surf along north facing and west shores will remain flat to tiny through the forecast period except for areas exposed to the easterly trade wrap.

HFO WATCHES/WARNINGS/ADVISORIES

None.