Fox News Weather Center

Hawaii on Alert for Heavy Rain, Wind From Hilda

Hilda, currently a tropical storm, will approach the Big Island of Hawaii with heavy rain, wind and dangerous surf over the next few days.

A surge of tropical moisture will advect across the islands of Hawaii despite the exact track of the system.

According to AccuWeather Meteorologist Evan Duffey, "Even if Hilda does not make a direct landfall, upslope flow still threatens to bring a significant amount of rainfall to the Big Island of Hawaii."

"Some areas of the Big Island, including the city of Hilo, could see flooding conditions," he added.

Wind gusts over 40 mph are possible from Hilda, especially along the southeast coast of the Big Island.

The heaviest rain bands may lead to localized flash flooding, especially across areas that have seen large amounts of rain so far this month. Any downpours could also lead to reduced visibility and the risk of hydroplaning for motorists traveling at highway speeds.

"Heavy rain will hit the Big Island beginning on Wednesday night; this will result in flash flooding and mudslides, especially along the southern mountains and eastern-facing slopes," Duffey said.

Locally gusty winds in the bands of rain or squalls can cause sporadic power outages.

In addition to the heavy rain and wind, dangerous surf and rip currents will occur.

Small craft operators should consider remaining in port late this week, as seas will build. Bathers, boarders and boaters should heed all advisories as they are issued.

Scary Flames Overtake Hawaiian Highway

Hilda is expected to track to the south of the Big Island, closely similar to the track of Iselle during early August of last year.

According to AccuWeather Senior Meteorologist Alex Sosnowski, "Hilda is likely to track much farther south than Guillermo and could take a track more similar to Iselle in 2014."

"Because of this track grazing or just missing the islands to the south, there is the potential for impacts similar to Iselle," Sosnowski said.

Iselle brought over a foot of rain to parts of the Big Island. Hilda could bring the same amount of rain to those locations over the next few days.

How El Niño Affects Tropical Activity Across the Atlantic and Pacific

An El Niño pattern is defined by above-normal sea-surface temperatures in the equatorial Pacific Ocean. Because tropical systems develop and strengthen due to warm ocean temperatures, this typically leads to a busy hurricane season across the eastern and central Pacific Ocean.

According to AccuWeather Meteorologist Edward Vallee, "As El Niño strengthens in the central and eastern Pacific, warm sea-surface temperatures provide a favorable environment for tropical systems to develop."

While the hurricane season is busy across the Pacific during an El Niño season, the Atlantic typically has below-average activity.

"In the Atlantic, a strengthening El Niño leads to increased wind shear, which highly inhibits hurricane development. This has led to significantly decreased tropical activity over the Atlantic for much of this season," Vallee said.

Despite being in the middle of the summer season, the peak period for tropical development across the Atlantic is not until the early to middle of September.