WWJP81 RJTD 081800 VITAL WARNING FOR NAHA NAVTEX AREA 081800UTC ISSUED AT 082100UTC PRESSURE GRADIENT IS STEEP GALE WARNING NORTHERN SEA OFF SHIKOKU, SOUTHERN SEA OFF SHIKOKU, SEA SOUTH OF OKINAWA WITH MAX WINDS 40 KT SEA AROUND AMAMI WITH 35 KT WARNING(NEAR GALE) HYUGA NADA, SEA OFF KAGOSHIMA, SOUTHERN PART OF EAST CHINA SEA, SEA EAST OF OKINAWA NXT WARNING WILL BE ISSUED BEFORE 090300UTC =