In general, the wettest periods on Maui occur during the winter months of November to March, although Wailea benefits from being on the leeward side of Maui, which means the weather at Grand Wailea is generally drier (and warmer) than the rest of the island, even during the winter.

While Maui is famous for its diverse microclimates, the rainiest month for the island as a whole is typically December. The "wet season" in Hawaii generally spans from November to March, when the northeast trade winds bring consistent moisture to the windward (eastern and northern) sides of the island. For instance, the town of Hana can see significantly higher rainfall totals during this time, often peaking in March or December. Conversely, the leeward (southern and western) regions like Kihei and Wailea remain much drier year-round due to the "rain shadow" effect of Haleakala. If you are planning a trip to the summit of Haleakala or the lush rainforests of East Maui, expect daily showers during the winter months. However, these rains are often passing "liquid sunshine" that clears quickly. For the driest and sunniest beach weather, travelers typically prefer the months of June through September, though the island's lush beauty is at its peak during the winter rainy season.