Tropical Cyclone Track Forecasting - Single Station Forecasting of A Tropical Cyclone Passage

Single Station Forecasting of A Tropical Cyclone Passage

About four days in advance of a typical tropical cyclone, an ocean swell of 1 metre (3.3 ft) in height will roll in about every 10 seconds, moving towards the coast from the direction of the tropical cyclone's location. The ocean swell will slowly increase in height and frequency the closer a tropical cyclone gets to land. Two days in advance of the center's passage, winds go calm as the tropical cyclone interrupts the environmental wind flow. Within 36 hours of the center passage, the pressure begins to fall and a veil of white cirrus clouds approaches from the cyclone's direction. Within 24 hours of the closest approach to the center, low clouds begin to move in, also known as the bar of a tropical cyclone, as the barometric pressure begins to fall more rapidly and the winds begin to increase. Within 18 hours of the center's approach, squally weather is common, with sudden increases in wind accompanied by rain showers or thunderstorms. Winds increase within 12 hours of the center's approach, occasionally reaching hurricane force. The ocean's surface becomes whipped with foam. Small items begin flying in the wind. Within 6 hours of the center's arrival, rain becomes continuous and the storm surge begins to come inland. Within an hour of the center, the rain becomes very heavy and the highest winds within the tropical cyclone are experienced. When the center arrives with a strong tropical cyclone, weather conditions improve and the sun becomes visible as the eye moves overhead. At this point, the pressure ceases to drop as the lowest pressure within the storm's center is reached. This is also when the peak depth of the storm surge occurs. Once the system departs, winds reverse and, along with the rain, suddenly increase. The storm surge retreats as the pressure suddenly rises in the wake of its center. One day after the center's passage, the low overcast is replaced with a higher overcast, and the rain becomes intermittent. By 36 hours after the center's passage, the high overcast breaks and the pressure begins to level off.