What to Wear in Hilo in May

Light, quick-drying fabrics are the foundation — technical athletic tops or linen in lightweight polyester blends rather than cotton, which stays wet after showers. A packable waterproof rain jacket in a daypack handles the 14 rainy days. Waterproof trail sandals (Teva, Chaco) or waterproof trail shoes handle the Hawaii Tropical Botanical Garden's perpetually wet paths and Akaka Falls State Park's rain-slicked boardwalk.

May is an excellent month for Hilo's natural wonders — Akaka Falls and Rainbow Falls are at high volume from consistent trade-wind rains, the Hawaii Tropical Botanical Garden is extraordinarily lush, and the Hilo Farmers Market's tropical abundance peaks with late-spring produce. Crowds are lighter than winter peak season. The frequent rain enhances rather than disrupts the experience of Hilo's landscape for visitors who dress appropriately.

Waterproof trail sandals are the most versatile choice — they handle the botanical garden's wet paths, the Wailuku River State Park's mist-slicked overlooks, and the Hilo Farmers Market's often-wet ground without issue. Waterproof trail shoes provide more grip on the slicker boardwalk sections at Akaka Falls. Standard flip-flops lack traction for trail use on wet surfaces; non-waterproofed shoes will be soaked within 30 minutes of outdoor walking.

Temperatures sit near 81°F with lows around 64°F — consistently warm and humid year-round. May brings about 14 days of precipitation, a moderately wet month by Hilo's extraordinary standards. The rain arrives as tropical trade-wind showers that can be intense for 30–90 minutes and then clear. The east-facing orientation of Hilo Bay ensures that trade-wind moisture arrives reliably; the combination creates the lush landscape that makes the area extraordinary.

Pack quick-drying lightweight fabrics (avoid cotton as primary fabric), a packable waterproof rain jacket, waterproof trail sandals or shoes, a dry bag or waterproof daypack liner for electronics, and broad-spectrum reef-safe sunscreen. The UV index can spike between showers at Hawaii's latitude. Insect repellent is useful for the botanical garden's interior sections where mosquitoes shelter in heavy vegetation.