Flossie (2013)

A tropical cyclone formed from a disturbance south of Mexico and became a tropical depression about 850 nautical miles west‑southwest of the southern tip of the Baja California peninsula at 0000 UTC 25 July 2013. It strengthened to Tropical Storm Flossie six hours later and moved generally westward into the Central Pacific. Flossie reached peak intensity on 27 July just east of 140°W, then weakened and moved across the Hawaiian Islands region, degenerating to a post‑tropical remnant low near the northern coast of Kauai by 1200 UTC 30 July.

Flossie did not make a classic hurricane landfall in the United States; it weakened as it approached Hawaii. It was a tropical depression about 20 nautical miles northeast of Maui at 0000 UTC 30 July and became a post‑tropical remnant low near Kauai at 1200 UTC 30 July. Tropical storm watches and warnings were issued for the Main Hawaiian Islands from 28 to 30 July, but tropical storm conditions did not occur across the entire warning area before the storm weakened.

The storm’s maximum sustained winds peaked at 60 knots (about 69 mph) and the lowest estimated central pressure was 994 mb at 1200 UTC 27 July, corresponding to a strong tropical storm (below hurricane strength). After peak, winds fluctuated and steadily declined under increasing upper‑level wind shear as Flossie approached Hawaii.

Flossie produced high surf in excess of 15 feet on east‑facing shores of the Main Hawaiian Islands, causing minor coastal inundation in places. Rainfall totals were generally 1.5 to 4 inches across the islands; the highest measured total was 9.27 inches at Mount Waialeale on Kauai. Other notable totals included 4.75 inches at Kilohana and 4.68 inches at Puu Kukui. The highest sustained wind at official observing sites was 31 kt (36 mph) at Keahole Airport (Kailua‑Kona) and the highest official gust was 43 kt (49 mph) at Kahului Airport (Maui).

Damage was minor and mainly affected Maui and Hawaii Counties on 29–30 July. More than 10,000 customers lost power across Maui and the island of Hawaii from lightning strikes and gusty winds. One man on Maui was injured when lightning struck and damaged his home. No deaths were reported in association with Flossie. Forecasts of Flossie’s development were generally good: the precursor disturbance was highlighted in forecasts days before formation, and official intensity forecasts were more accurate than typical 5‑year averages, though official track errors were larger than the recent mean at several forecast times.