A Flash Flood Watch remains posted for all Hawaiian islands until 6 p.m. as deep tropical moisture from the remnants of former tropical cyclone Wali spreads across the island chain brings the potential for heavy rain, flash flooding and a slight chance of thunderstorms through Monday, according to the National Weather Service.
The NWS says that there is also potential for isolated thunderstorms during the next couple of days.
This will be the second time this year that moisture from a former tropical cyclone has reached the islands. In fact, it's the second time this week, after Fausto's remnants dumped rain on the Big Island and brought humidity statewide last Sunday and Monday.
"There were will a few pockets of really heavy rain on the Big Island," said NWS Meteorologist Bob Ballard. "This is going to be sort of an extra punch. It's got a few more ingredients working for it that we didn't have with Fausto."
According to the NWS, “All the islands will be impacted by heavy rain at some point, but with the moderate trades still focusing the bulk of the rain over windward and mountain areas. Leeward areas, which are typically drier, do not require as much rainfall to see flash flooding. So the threat will encompass all areas of the aloha state through Monday.”
"Systems like this in the past have brought torrential amounts of rain," said Ballard. "Certainly I think five to ten inches is not out of the question."Emergency crews around the state began taking action Friday, ahead of the storm. The state has already begun closing trails and campgrounds. On Oahu, emergency management crews said streams and culverts appear ready to handle the possible floodwaters.
"Our Department of Emergency Management volunteer reservists also went out to assist our city crews to go check out the streams, areas we know that commonly flood out."