723 WWHW40 PHFO 201331 WSWHFO URGENT - WINTER WEATHER MESSAGE National Weather Service Honolulu HI 331 AM HST Fri Apr 20 2018 HIZ028-210245- /O.EXT.PHFO.WS.W.0003.000000T0000Z-180421T1600Z/ Big Island Summits- 331 AM HST Fri Apr 20 2018 ...WINTER STORM WARNING NOW IN EFFECT UNTIL 6 AM HST SATURDAY... * WHAT...Heavy snow occurring. Plan on difficult travel conditions. Additional snow accumulations of 4 to 6 inches are expected. * WHERE...Big Island Summits. * WHEN...Until 6 AM Saturday. * ADDITIONAL DETAILS...Be prepared for significant reductions in visibility at times. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Winter Storm Warning for snow means severe winter weather conditions are occurring. Strong winds are also possible. This will make travel very hazardous or impossible. $$