The National Weather Service has issued a winter storm warning because significant snow, sleet and ice and expected or occurring on summits, above 11,000 feet. Officials have also issued a flash flood watch for the entire island.
The watch and warning are in effect starting tonight to 6 p.m. Friday, according to the Honolulu Forecast Office.
Developing instability combined with an area of moisture moving toward the island from the east are expected to produce heavy showers, as well as the possibly of thunderstorms over mainly windward slopes. Such conditions will bring high chances for flooding while afternoon convection will bring a flooding threat to leeward slopes.
Flash flooding is very dangerous and it does not have to be raining heavily where you are for it to occur. The public is advised to avoid camping or hiking near streams and low-lying flood-prone areas.
Periods of snow will persist today on summits, with heavier snowfall expected to develop overnight and Friday. Expected snow accumulations are less than 2 inches today, followed by 6 to 12 inches by Friday.
Already there are hazardous driving conditions in the affected area. Treacherous conditions, which may make roads impassable, are expected tonight and Friday. Limited visibility because of clouds and precipitation is also happening.
For more information, visit www.prh.noaa.gov/hnl.