Tropical Storm Flossie strengthened overnight and may still be a tropical storm when it reaches Hawaii island sometime Monday night.The storm, which is about 1,500 miles east of Honolulu, has maximum sustained winds of 60 mph with higher gusts. Tropical storm force winds extend 70 miles from the center of the storm. Flossie is moving west-northwest at 18 mph.National Hurricane Center forecasters say the system has become better organized and could still strengthen overnight before weakening as it moves over cooler waters. There is a 5 percent chance it could reach hurricane strength Friday.But forecasters say the system will most likely weaken to a tropical depression by Monday night. There is a chance Flossie may still be a tropical storm with stronger winds Monday night and a 1 percent chance it could be a category 1 hurricane.National Weather Service forecasters say the storm is still too far away to predict its exact impact on Hawaii. The projected path of the storm and its intensity could change significantly by Monday, forecasters said.The current forecast for Honolulu on Monday night through Tuesday night calls for a 70 percent chance of locally heavy rain, with the chance of thunderstorms and northeast winds of 15 to 25 mph, shifting to the east at 20 to 30 mph Tuesday afternoon.Showers are also likely on Wednesday and should clear by Wednesday night or Thursday morning.“The atmosphere will stabilize behind Flossie, returning us to a more typical trade wind pattern of clouds and showers for the second half of the week,” the National Weather Service in Honolulu said.