Forecast: Diminishing trade winds will make for a humid Thursday
May 19, 2016 at 9:01 AM HST - Updated July 10 at 11:20 PM
Good Thursday morning. Moisture associated with an old front brought a round of showers to windward neighborhoods on Wednesday. Now we are expecting the winds to slow down as we head into Thursday.
What is the reason for the slowdown? We are tracking a front that will advance closer to the Garden Isle later today within 450 miles of Kauai. This will result in weakening the area of high pressure to our north. This feature usually cranks up the trade winds when it is parked off of the islands. Your Thursday forecast calls for a slowdown in our winds by a notch or two, making it feel more humid.
Plan your morning commute accordingly, because we are also tracking another pocket of moisture. This pool of showery weather is expected to impact the eastern end of the island chain. Showers will remain focused over windward slopes with little change in stability. The islands' mountain ranges will act like a dam to keep moisture gathered over windward sides when passing over the islands.
As we head into the weekend, you can expect for the trade winds to pick back up as the front to the northwest dissipates and an area of high pressure strengthens with a clockwise flow bringing in the trade winds. We may see more enhanced low level moisture moving along the trade wind flow during this period, so your best shot at abundant sunshine will likely be over leeward sides depending on the moisture in our wind flow.
We are definitely feeling warmer, as the heat is on especially during the afternoon! But one element that also reminds us summer is close by, is the change in surf activity. We have a small, long-period south swell on our radar, as nearshore buoys are becoming more elevated. The source of this swell energy is from Tasmania. This source will continue to fill in through the day and hold at moderate levels through Friday before trending down over the weekend. Rough surf along east facing shores persist through much of the period, with slightly lower surf expected late Thursday and Friday.