Breezy trade winds will continue through most of the week. Showers will favor windward and mauka areas, most frequently at night and during the early morning hours. Late this week into the weekend, an upper-level disturbance may bring a slight uptick in trade wind shower coverage.
Issued at 928 AM HST Tue May 12 2026
High pressure far north of the islands will maintain a breezy trade wind pattern over the regions over the next several days. Mid-level ridging will help to limit shower activity with a stable airmass in place.
Limited showers being carried in on the trade wind flow are impacting the windward sides of Kauai and the Big Island. AIRMET Sierra is in effect for mountain obscuration on the east sides of those islands as a result. Conditions are likely to improve this afternoon, but could return overnight. VFR conditions are expected elsewhere.
AIRMET Tango remains in effect for mechanical turbulence to the lee of the mountains due to the breezy trade winds. Expect this to remain in place over the next couple of days. An additional AIRMET Tango has been issued for upper level turbulence as the result of an upper level jet moving over the islands. This is expected to move to the east of the islands late this afternoon.
Issued at 350 AM HST Tue May 12 2026
High pressure remains in place north of the Hawaiian Islands into the first half of next week, keeping fresh to locally strong trades blowing through Thursday. An upper level disturbance moves into the Hawaii region from the north from Friday into the weekend. Expect increasing clouds and shower trends along with a slight decrease in trade wind speeds as a low level trough develops over the islands. The Small Craft Advisory was extended through Wednesday afternoon, and will likely continue into Thursday for the typical windier waters and channels near Maui and the Big Island.
A small short to medium period northwest (330 deg) swell will slowly decrease through tonight. The next small long period northwest swell arrives into the western islands by Wednesday afternoon, peaking on Thursday, then slowly fading into Friday. Expect small surf to continue along north and west facing shores of the western islands at least into Thursday.
The small long period south swell energy will continue to show a slow decline through the week with the period dropping by 1 second each day. The next small long period south swell arrives on Saturday, keeping surf heights elevated along south facing shores. Slightly elevated surf along E facing shores continues until trades weaken this weekend.
Small Craft Advisory until 6 PM HST Wednesday for Alenuihaha Channel-Big Island Leeward Waters-Big Island Southeast Waters- Maalaea Bay-Pailolo Channel.
