HONOLULU (CBSNews.com) - Tropical Storm Flossie moved westward Sunday across the central Pacific toward Hawaii, where a tropical storm warning has been issued for Hawaii and Maui counties.
Flossie has maximum sustained winds near 65 mph with higher gusts, the National Weather Service said. It's moving toward the islands at about 20 mph and landfall could come after midnight Monday.
The advisories for Hawaii and Maui counties were in place as of 11 p.m. Saturday, meaning tropical storm-force sustained winds of 39 mph or more are expected within 36 hours. Oahu is under a tropical storm watch, which means tropical storm conditions are expected within 48 hours.
Flossie's center was expected to pass near the Big Island and Maui on Monday and then south of Oahu several hours later.
According to CBS meteorologist David Bernard, residents should be wary of the potential for flooding on mountainous terrain.
The Federal Emergency Management Agency (FEMA) said they were closely monitoring the situation
"Residents and visitors to the Hawaiian Islands should closely monitor the storm and take steps now to be prepared," said FEMA Administrator Craig Fugate in a press release. "Stay away from flood waters, never drive through flooded roadways and follow the direction of emergency officials."
A flash flood watch was issued for all islands from Monday morning through Tuesday night, according to the Honolulu Star Advertiser.
The storm could drop up to 15 inches of rain to windward areas of Maui and Hawaii counties, and 6 to 10 inches in other areas, forecasters said. Up to a foot of rain could fall on windward Oahu and 4 to 8 inches in central and leeward areas. Kauai may see 2 to 4 inches of rain, with up to 6 inches on windward slopes.
"Rock and mudslides caused by the rainfall will be possible around or near mountain slopes. The heavy rain will also fall over urban areas in the lower elevations, which will be more susceptible to flooding problems," the National Weather Service said.
The storm is expected to weaken as it moves toward and over the islands, but the current forecast track keeps it as a tropical storm through Wednesday.
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