HONOLULU (HawaiiNewsNow) - Thursday is pretty much a transition day in weather; we go from light winds to increased moisture and the return of the trade winds. An increasing moist and unstable air mass will also bring the possibility of thunderstorms and locally heavy rainfall Thursday night into the weekend. We have high pressure up to the north of the islands which keeps the trade winds coming, but the upper trough moving over the islands will bring the added rainfall.