Windward Maui soaks up above-average May rainfall while leeward areas stay dry

Maui County’s rainfall totals for May followed a familiar pattern — above average moisture on windward slopes, near-drought conditions on the leeward and interior sides — while a West Maui summit station recorded its wettest May in two decades, according to a National Weather Service summary.

The US Geological Survey Puʻu Kukui rain gauge, perched on the West Maui Mountains, led all county stations with 37.37 inches for the month — 134% of its May average — and logged a single-day peak of 7.43 inches on May 15. The weather service noted it was the site’s wettest May since 2005, with a caveat regarding data gaps in 2015.

The contrast across the island was stark. Most leeward and interior locations recorded 60% or less of their normal May rainfall, continuing a pattern the NWS also observed on Kauaʻi and Oʻahu during the same period.

Despite the dry month for much of the county, the longer-term picture looks healthier. Year-to-date totals at all reporting stations in Maui County were near to well above average, ranging from roughly 100% to 300% of normal through the end of May. Puʻu Kukui led that category as well, with 170.63 inches recorded so far in 2025 — 105% of its year-to-date average.

The National Weather Service Honolulu office publishes monthly rainfall summaries for Maui and for Molokaʻi and Lānaʻi through its Hawaiʻi hydrological summary series.