Tropical cyclone rainfall forecasting involves using scientific models and other tools to predict the precipitation expected in tropical cyclones A tropical cyclone is a storm system characterized by a large low-pressure center and numerous thunderstorms that produce strong winds and heavy rain. Tropical cyclones feed on heat released when moist air rises, resulting in condensation of water vapor contained in the moist air. They are fueled by a different heat mechanism than other cyclonic such as hurricanes and typhoons. Knowledge of tropical cyclone rainfall climatology A tropical cyclone rainfall climatology is developed to determine rainfall characteristics of past tropical cyclones. A tropical cyclone rainfall climatology can be used to help forecast current or upcoming tropical cyclone impacts. The degree of a tropical cyclone rainfall impact depends upon speed of movement, storm size, and degree of vertical is helpful in the determination of a tropical cyclone rainfall forecast. More rainfall falls in advance of the center of the cyclone than in its wake. The heaviest rainfall falls within its central dense overcast and eyewall The eye is a region of mostly calm weather found at the center of strong tropical cyclones. The eye of a storm is a roughly circular area and typically 30–65 km in diameter. It is surrounded by the eyewall, a ring of towering thunderstorms where the most severe weather of a cyclone occurs. The cyclone's lowest barometric pressure occurs in the. Slow moving tropical cyclones, like Hurricane Danny (1997) and Hurricane Wilma Hurricane Wilma was the most intense hurricane ever recorded in the Atlantic basin. Wilma was the twenty-second storm , thirteenth hurricane, sixth major hurricane, and fourth Category 5 hurricane of the record-breaking 2005 season (the record for most Category 5 storms in a single season was previously held by the 1933 season), can lead to the highest rainfall amounts due to prolonged heavy rains over a specific location. However, vertical wind shear Wind shear, sometimes referred to as windshear or wind gradient, is a difference in wind speed and direction over a relatively short distance in the atmosphere. Wind shear can be broken down into vertical and horizontal components, with horizontal wind shear seen across weather fronts and near the coast, and vertical shear typically near the leads to decreased rainfall amounts, as rainfall is favored downshear and slightly left of the center and the upshear side is left devoid of rainfall. The presence of hills or mountains near the coast, as is the case across much of Mexico The United Mexican States (Spanish: Estados Unidos Mexicanos ), commonly known as Mexico (English: /ˈmɛksɪkoʊ/) (Spanish: México (help·info) [ˈmexiko]), is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize,, Haiti Haiti , officially the Republic of Haiti (République d'Haïti ; Repiblik Ayiti), is a Creole- and French-speaking Caribbean country. Along with the Dominican Republic, it occupies the island of Hispaniola, in the Greater Antillean archipelago. Ayiti (Land of high mountains) was the indigenous Taíno or Amerindian name for the mountainous western, the Dominican Republic The Dominican Republic is a nation on the island of Hispaniola, part of the Greater Antilles archipelago in the Caribbean region. The western third ofthe island is occupied by the nation of Haiti, making Hispaniola one of two Caribbean islands that are occupied by two countries. Both by area and population, the Dominican Republic is the second, much of Central America Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. Most of Central America is considered to be part of the Mesoamerican biodiversity hotspot, Madagascar Madagascar, or Republic of Madagascar , is an island nation in the Indian Ocean off the southeastern coast of Africa. The main island, also called Madagascar, is the fourth-largest island in the world, and is home to 5% of the world's plant and animal species, of which more than 80% are endemic to Madagascar.[citation needed] They include the, Réunion Réunion (French: Réunion or formally La Réunion French pronunciation ; previously Île Bourbon Tamil: இறியூனியன்) is an island located in the Indian Ocean, east of Madagascar, about 200 kilometres (120 mi) south west of Mauritius, the nearest island, China China (simplified Chinese: 中国; traditional Chinese: 中國; Hanyu Pinyin: Zhōngguó ; Tongyong Pinyin: Jhongguó; Wade-Giles: Chung¹kuo²) is a cultural region, an ancient civilization, and, depending on perspective, a national or multinational entity extending over a large area in East Asia, and Japan Japan is an island country in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, People's Republic of China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south. The characters which make up Japan's name mean "sun-origin", which act to magnify amounts on their windward side due to forced ascent causing heavy rainfall in the mountains. A strong system moving through the mid latitudes, such as a cold front The cooler, denser air wedges under the less dense warmer air, lifting it, which can cause the formation of a narrow line of showers and thunderstorms when enough moisture is present. This upward motion causes lowered pressure along the cold front. On weather maps, the surface position of the cold front is marked with the symbol of a blue line of, can lead to high amounts from tropical systems, occurring well in advance of its center. Movement of a tropical cyclone over cool water will also limit its rainfall potential. A combination of factors can lead to exceptionally high rainfall amounts, as was seen during Hurricane Mitch Hurricane Mitch was the most powerful hurricane of the 1998 Atlantic hurricane season, with maximum sustained winds of 180 mph . The storm was the thirteenth tropical storm, ninth hurricane, and third major hurricane of the season. At the time, Hurricane Mitch was the strongest Atlantic hurricane observed in the month of October, though it has in Central America Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. Most of Central America is considered to be part of the Mesoamerican biodiversity hotspot.[1]
Use of forecast models can help determine the magnitude and pattern of the rainfall expected. Climatology Climatology is the study of climate, scientifically defined as weather conditions averaged over a period of time, and is a branch of the atmospheric sciences. Basic knowledge of climate can be used within shorter term weather forecasting using analog techniques such as the El Niño - Southern Oscillation (ENSO), the Madden-Julian Oscillation (MJO), and persistence models, such as r-CLIPER, can create a baseline for tropical cyclone rainfall forecast skill. Simplified forecast models, such as the Kraft technique and the eight and sixteen-inch rules, can create quick and simple rainfall forecasts, but come with a variety of assumptions which may not be true, such as assuming average forward motion, average storm size, and a knowledge of the rainfall observing network the tropical cyclone is moving towards. The forecast method of TRaP assumes that the rainfall structure the tropical cyclone currently has changes little over the next 24 hours. The global forecast model which shows the most skill in forecasting tropical cyclone-related rainfall in the United States The United States of America is a federal constitutional republic comprising fifty states and a federal district. The country is situated mostly in central North America, where its forty-eight contiguous states and Washington, D.C., the capital district, lie between the Pacific and Atlantic Oceans, bordered by Canada to the north and Mexico to the is the GFS (Global Forecasting System).
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The existing radar systems, with capabilities limited to detection and monitoring of . tropical cyclones. forming in the Pacific Ocean, will have to be upgraded to enable Pagasa to provide advisories on . rainfall. volume and wind velocity. ... the Doppler radar can provide hourly weather update and accurate time and amount of . rainfall. in a given area as well as the wind velocity of a . tropical cyclone. . The Doppler radar is the most advanced instrument in weather . forecasting. . ...
