Honolulu residents can anticipate a wind-down of the gusty trade winds today as the high-pressure system over the northeast begins its steady weakening. Showers are expected to continue favoring the windward areas, while the leeward Big Island slopes might see some afternoon rain activity. Heading into the weekend and early next week, light east to southeast trades will allow for the possibility of sea breezes and scattered leeward showers, according to the National Weather Service (NWS)
To refine predictions, the NWS has adjusted its precipitation outlook for windward sections upwards for tonight, aligning with the National Blend of Models which incorporates higher-resolution data, while a more significant increase in probabilities is anticipated for Saturday night through to Monday, particularly over coastal waters and windward spots, although leeward areas should see little change the PoPs over the windward sections of the islands were nudged upwards tonight in line with the National Blend of Models which includes higher resolution models. The shift eastward of a 1029 mb high-pressure system has begun to lessen the hold of the trade winds and introduce instability into the region, potentially leading to increased shower activity, especially from Friday night onward.
Forecasters are keeping a close eye on the development of an upper-level disturbance and a surface low-pressure system located approximately 700 miles northwest of Kauai, which are contributing factors to the changing wind patterns and instability over the islands. This shift could bring about east and southeast winds, along with a slight rise in potential thunderstorm activity north of the islands between Saturday night and Sunday night, as noted across multiple model agreements including GFS and ECMWF, with the highest possibilities of heavy showers lingering just north of the island chain, nevertheless the exact placement remains uncertain and is therefore not yet included in the forecast grids at this time. Winds could strengthen briefly on Sunday as the low diminishes, after which a somewhat unstable weather pattern featuring light to moderate east to east-southeast winds is expected for the early part of next week.
In aviation news, the current breezy conditions will persist through this morning before trending downwards over the weekend, with scattered showers mainly affecting the windward regions potentially causing intermittent MVFR ceilings and visibility the aviation sector sees moderate low-level turbulence as a continuing challenge while the AIRMET Tango warning remains in effect through this morning at least, but is expected to be lifted by tonight as the trade winds ease. As we move into next week, marine forecasts suggest a brief pick-up in trade wind strength on Sunday, with a new high passing north of the state, followed by a potential shift in conditions as a low approaches from the northwest leading to the easing of wind speeds particularly over the western parts of the state.
The NWS has issued a Small Craft Advisory effective until this evening for specific areas, and surf conditions along east-facing shores are predicted to remain rough, albeit slightly easing today and Saturday. As we approach Wednesday, a more stable trade wind flow is anticipated to return, establishing a sense of normalcy in the weather patterns after varied fluctuations over the early days of the week.
