Garden Isle has below average rainfall for July, according to monthly report

Rainfall in July was far and few between throughout the state, with the sole notable rain event occurring on Kaua‘i, which resulted in flooding.

Rainfall totals were mainly below average for Kauaʻi last month, outside of northern and central portions of Garden Isle where the Hanalei and Waiahi gauges received 126% and 100% of their monthly totals between July 19-20, according to the monthly rain summary report from the National Weather Service.

Leeward portions of the island turned in another dismal month with most sites only 20 to 30% of their July averages. The USGS gage on Mt. Waiʻaleʻale, once again, had the highest monthly total with 33.50 inches (86% of average), and the highest daily total of 6.46 inches on the 19th.

This site’s monthly and highest daily totals were also the highest across the entire state for July.

July began with a typical summer trade wind pattern dominated by high pressure to the north and stable conditions aloft, the monthly report indicated. Moderate to locally breezy trades brought generally dry weather through July 4, with only modest windward and mauka showers.

The most notable rain event occurred on the 19th and 20th due to a combination of above-average moisture and instability from a weak mid-level low northwest of Kauaʻi, where there was significant flooding, including road closures and elevated river levels, easily verifying the Flash Flood Warning issued the morning of the 20th. Mount Waiʻaleʻale recorded nearly 8 inches of rain in 24 hours.

Aside from a few – mainly south and east coast sites – in the 30 to 60% range, the majority of the year-to-date totals are now around 70% of average or higher, with several inland sites running above average. The Mt. Waiʻaleʻale gauge continues to have the highest year-to-date total for Kauaʻi County and the state as a whole with 199.08 inches, though still only 88% of their average through July.