Storms, encouraged by the El Nino effect, continued to soak the island and strike it with lightning on Monday, forecasters said.
Storms, encouraged by the El Nino effect, continued to soak the island and strike it with lightning on Monday, forecasters said.
The storms cut out traffic signals along several routes, including Queen Kaahumanu Highway. This led to numerous slowdowns for motorists. Lights were sometimes flashing red or flashing yellow, and not all drivers obeyed the new directions. In various locations, police officers were assigned to provide direction.
A flash flood advisory ran until 7:45 p.m. Monday. This overlapped with a flash flood watch that was scheduled to end at 6 p.m. before ultimately being extended to end at 6 p.m. Tuesday.
Rain was especially heavy in the Ka‘u District, with 4.49 inches reported over a 24 hour period at the Pahala rain gauge.
Because of heavy runoff and flooding, Highway 11 near Whitington Beach Park in Ka‘u was periodically closed to all traffic in an area that ran from Punaluu to Naalehu.
Students from Pahala area schools were dropped off before the road was closed again.
Forecaster Ray Tanabe said the unusually heavy rains happening on the dry side of the island are largely the result of the changes El Nino is creating in the Pacific. El Nino is when ocean temperatures in the east-central equatorial Pacific rise as much as five degrees Celsius above average. The effect is also contributing to the high number of tropical depressions and tropical storms seen so far this season, he said.
Tanabe said the thunderstorms and heavy showers should reduce in number and intensity for Tuesday and Wednesday.
The county advised drivers to “drive carefully and to be prepared for hazardous conditions, ponding, and runoff, and to anticipate traffic delays.”
Rain totals in other areas were not as extreme as Pahala. Waikoloa saw 1.69 inches over the past 24 hours, while Kona International Airport recorded 1.4 inches in the same time period and the Waimea stations reported an average of 0.66 inches.