textproduct: Honolulu

SYNOPSIS

Trade winds will steadily strengthen through Thursday and could produce advisory level winds by Thursday afternoon, especially over Maui County and the Big Island. Passing showers will continue to ride in with the breezy to windy trade winds through early next week, primarily during the nights and early morning hours across windward and mauka areas.

DISCUSSION

This morning's radar and satellite imagery shows scattered showers riding in with the breezy trade winds mainly over windward and mauka areas. As we go through the day today and into tonight, trade winds will steadily strengthen and a drier air mass will move over the state. With the drier air mass in place by Thursday, showers will remain on the lighter side, but we should continue to see scattered showers over windward and mauka areas.

As the drier air mass moves in on Thursday, the inversion will lower and strengthen, which will result in some gusty winds over and lee side of terrain. Winds are expected to reach advisory thresholds on Thursday for the windier areas around Maui County and the Big Island, where gusts of up to 50 mph will be possible. For Oahu, wind gusts should be slightly weaker but gusts of at least 40 mph should be expected for areas downwind of terrain by late Thursday.

For the weekend, windy conditions will likely continue through Saturday. Trade winds could drop a notch on Sunday, but nonetheless breezy to strong trades will likely continue through early next week. Passing showers will continue to ride in with the strong trades from time to time and will mainly be focused over windward and mauka areas.

AVIATION

Fresh to strong trade winds will be in place today through Friday. Showers will mostly affect windward and mountain areas as well as the night time and early morning hours as a band of moisture fills in this morning. Drier air is expected to fill in later today into tonight, limiting showers. Brief MVFR conditions are expected in the showers, but otherwise VFR conditions will prevail.

AIRMET Sierra for mountain obscuration is in place for Kauai due to the clouds and showers. This AIRMET will likely be canceled later today as drier air moves in. AIRMET Tango is in place due to strengthening trade winds and will likely remain in place through the day.

MARINE

The high pressure ridge north of the Hawaiian Islands will strengthen over the next few days into the strong to gale range from Thursday into early Friday morning. A Gale Watch was issued for the Alenuihaha and Pailolo Channels. A Small Craft Advisory (SCA) remains in effect and will expand to all island waters by Thursday. Expect SCA to continue into the first half of next week.

Small, short to medium period north-northwest (330 degree) swell energy will decline through Thursday. The next small north- northwest (330 degree) swell will move into the Hawaii region on Saturday increasing surf heights along north and west facing shores through the weekend.

A series of small, long period south swell energy supports near- average surf along south facing shores over the next seven days. Meanwhile, strengthening trades maintain elevated surf along east facing shores into next week.

HFO WATCHES/WARNINGS/ADVISORIES

Small Craft Advisory from 6 PM this evening to 6 AM HST Friday for Kauai Channel-Kauai Leeward Waters-Kauai Northwest Waters- Kauai Windward Waters-Oahu Windward Waters.

Small Craft Advisory until 6 AM HST Friday for Big Island Leeward Waters-Big Island Southeast Waters-Big Island Windward Waters-Kaiwi Channel-Maalaea Bay-Maui County Leeward Waters-Maui County Windward Waters-Oahu Leeward Waters.

Small Craft Advisory until 6 AM HST Thursday for Alenuihaha Channel-Pailolo Channel.

Gale Watch from Thursday morning through late Thursday night for Alenuihaha Channel-Pailolo Channel.