WWJP74 RJTD 180000 IMPORTANT WARNING FOR OTARU NAVTEX AREA 180000UTC ISSUED AT 180300UTC PRESSURE GRADIENT IS STEEP WARNING(NEAR GALE) SEA WEST OF SAKHALIN, SEA OFF HIYAMA AND TSUGARU WARNING(DENSE FOG) SEA WEST OF HOKKAIDO, SEA OFF SOUTHERN COAST OF MARITIME PROVINCE POOR VIS 0.3 MILES OR LESS IN PLACES WARNING(ICING) SEA WEST OF SAKHALIN NXT WARNING WILL BE ISSUED BEFORE 180900UTC =