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"question answers"
"Gale Imminent Within 6 hours"
"Gale Soon 6-12 hours"
"Gale Later More than 12 hours"
"Pressure above 1020 millibars (mb) and steady Settled weather for about 24 hours"
"Rapid fall, 10 mb in 3 hours Worsening weather and strengthening backing (anticlockwise) winds or gale"
"Steady pressure fall Gradually worsening weather"
"Rapid rise Brings clear skies and some wind veering ( clockwise) shifting"
"Steady pressure rise Better weather coming"
"Speed of weather, slowly 0-15 kt"
"Speed of weather, steadily 15-25 kt"
"Speed of weather, rather quickly 25-35 kt"
"Speed of weather, rapidly 35-45 kt"
"Speed of weather, very rapidly Over 45 kt"
"Visibility good More than 8 km"
"Visibility moderate 3-8 km"
"Visibility poor 1097 m - 3 km"
"Visibility fog Less than 1097 m"
"Tropical cyclone within ""x"" km of HK a warning is issued by HK Observatory 800 km"
"Signal 1 Advisory"
"Signal 3 Strong wind 41-62 km/hr"
"Signal 8 Gale force wind 63-117 km/hr"
"Signal 9 Increasing gale"
"Signal 10 Typhoon wind speeds 118 km/hr or more"
"Strong monsoon signal Black ball"
"Force 0 Calm, less than 1 knot, mirror"
"Force 1 Light air, 1-3 knots, ripples"
"Force 2 Light breeze, 4-6 knots, small wavelets"
"Force 3 Gentle breeze, 7-10 knots, large wavelets, scattered white horses"
"Force 4 Moderate breeze, 11-16 knots, small waves, frequent white horses"
"Force 5 Fresh breeze, 17-21 knots, moderate waves, many white horses"
"Force 6 Strong breeze, 22-27 knots, Yachtsman's gale, large waves, foam crests"
"Force 7 Near gale, 28-33 knots, very large waves"
"Force 8 Gale, 34-40 knots, high waves"
"Force 9 Strong gale, 41-47 knots"
"Force 10 Storm, 48-55 knots"
"Force 11 Violent storm 56-63 knots"
"Force 12 Hurricane, 64 knots and over"
"Force to wind calculation Force number -1 x 5 = knots"
"Wind blows over large areas of water uninterrupted by land creating considerable wave height Fetch"
"Radar reflector Voyages outside of HK waters"
"Lifebuoy 760 mm Support 2 persons"
"Lifebuoy 610 mm Support 1 person"
"Lanyard Rope"
Created by: JASW