Honolulu residents can expect gentle to moderate trade winds this weekend as a surface trough approaches from the east, according to the latest reports from the National Weather Service (NWS) in Honolulu. Forecasters anticipate that this trough will bring increased cloudiness and showers to windward, and mauka areas. However, there is a silver lining as conditions are expected to clear up, with trade winds strengthening by midweek.
The trough, currently to the east of the islands, is set to dissipate before reaching Hawai'i, however, "remnant moisture from the trough will continue to be carried into the islands on the trade wind flow," NWS reports. This may escalate clouds and showers, particularly on the windward side of the Big Island, later today with the possibility of spreading across other islands by tonight, and Sunday.
Weather models show consensus on high pressure rebuilding to the northeast of Hawai'i early in the following week, making way for moderate to locally breezy trades. There remains some uncertainty due to potential tropical developments south of Hawaii, which could affect how much the trade winds will strengthen. Alongside, forecasters are also expecting a drier air mass to make its way back to the archipelago.
In aviation news, the approaching surface trough will soften the trade winds over the weekend. While "predominately VFR conditions are expected to prevail," localized showers may bring temporary MVFR conditions over windward regions as noted by the NWS. Current conditions indicate no AIRMETs in effect, signaling a relatively stable situation for air travel within the near term.
On the marine front, the weakening of high pressure northeast of the state translates into gentle to locally fresh trade winds through Monday, with a progressive strengthening expected into midweek. For surfers, the south-facing shores should maintain small waves throughout the weekend due to mostly medium-period background swells, though a storm-force low east of New Zealand could potentially bring a heftier swell to the islands in the latter part of next week. The NWS has increased confidence that "this low will generate a moderate to large long period south swell that may approach or exceeds the High Surf Advisory threshold as it peaks."
Fire weather concerns are expected to decline, as the surface trough is bringing higher humidity and increased clouds and showers to the region. This will continue until early next week, when the strengthening trade winds and a return to drier conditions may again raise fire weather considerations, the NWS cautions.
No watches, warnings, or advisories are currently in place, making for a relatively mild weather period for residents and visitors alike to enjoy the island with typical precautions for changing conditions typical of Hawai'i's diverse microclimates.
