Parade of Pacific typhoons spinning toward Asia

Three typhoons spinning within 1,000 miles of one another are intensifying toward super typhoon status within the next 48 hours, and are raising alarms in far southwest Japan, including the island of Okinawa, as well as Taiwan and southeastern China. While the track and intensity forecasts are still uncertain for these two destructive storms, it is likely that one Typhoon Chan-hom is headed for a landfall in China, potentially near Shanghai, a coastal city of 15 million, after threading the needle between northern Taiwan and Okinawa. Any deviation from this track could bring destructive winds and storm surge flooding to Okinawa or Taiwan. The U.S. has a large military presence on Okinawa, mainly at Anderson Air Base. The Joint Typhoon Warning Center (JTWC) is predicting that Typhoon Chan-hom, which is named after a tree found in Laos, is expected to peak its intensity at 125 knots by Thursday morning (ET). This would be about 140 miles per hour, or just shy of super typhoon status, which occurs at 130 knots, or 150 miles per hour. Despite Tropical Storm Linfa (Egay) being a relatively weaker storm it still resulted in wide spread problems across the Philippines, mainly due to the heavy rainfall the storm ushered in throughout the country. For starters shipping was ordered to remain in harbor and some flights were cancelled in the northern Philippines, while schools were closed in the capital, Manila, on Monday due to flooding and landslides from a tropical storm, disaster officials said. Storm warnings were issued in at least 14 areas of the main Philippine island of Luzon as tropical storm Linfa. Heavy rainfall warnings as well were issued from Manila North forcing numerous schools to close including many in the Manila area. Floods swamped much of the La Union submerging some homes up to the second floor in some locations. Given the uncertainty of intensity forecasts this far in advance, it's conceivable that Chan-hom, too, will reach super typhoon status. Depending on its intensity at the time, the storm could cause significant damage to coastal urban areas, particularly if it brings a high storm surge with it.


The storm has a broad wind field that is getting even larger, which makes it capable of moving more ocean water around and resulting in more of a surge compared to smaller typhoons and hurricanes of a similar intensity. Most of Shanghai is low-lying, at less than 10 feet above sea level. This makes the city vulnerable to storm surge flooding and flooding from heavy rains as well. Just behind Typhoon Chan-hom is Typhoon Nangka, which is expected to intensify to super typhoon status within 24 to 36 hours, according to JTWC forecasters. The JTWC is operated by the U.S. Air Force and Navy, and is tasked with tracking tropical cyclones across the Pacific, Indian Ocean, and many other areas. The storm is benefiting from the position and influence of a tropical upper tropospheric trough, known by the meteorological acronym "TUTT," which is helping to evacuate air from the northern part of the typhoon. Enhancing the outflow of air at upper levels of the atmosphere helps tropical cyclones grow, since they are sucking in so much air from the lower atmosphere, converting it to energy, and vaulting it to high heights. A lack of adequate outflow can often stymie such storms. Typhoon Nangka is forecast to make a turn to the north-northeast late this week, potentially putting Japan in the crosshairs, or sparing that island nation entirely, and instead recurving over the open waters of the Pacific. Another storm behind Nangka Behind Typhoon Nangka is another tropical disturbance that appears to be poised to form into a tropical storm. This system may threaten Hawaii by the weekend, which is why the National Oceanic and Atmospheric Administration (NOAA) has flown hurricane hunter aircraft to the islands in case storm surveillance is needed. There is another storm currently spinning near the Philippines, too, which is a weak tropical storm known as Linfa. That storm is expected to rain itself out over southeastern China in the coming days, and is not likely to be a major wind or storm surge threat. However, flooding may result from this slow-moving system. Two factors explain the boom in Pacific storms The burst of storm activity has to do with two main factors: a strengthening El Niño event and the Madden-Julian Oscillation. The El Niño event is bringing much above average ocean temperatures to a broad area of the tropical Pacific Ocean, roughly from the international dateline eastward to South America, though there are some areas of above average water temperatures all the way west toward the Philippines. The sudden burst of activity in the central and western Pacific Ocean follows a six-week lull in activity there, after this part of the world had its most active start to the typhoon season on record. Three of the first four typhoons that developed reached the equivalent of a Category 5 hurricane, and the planet has already seen as many Category 5 storms as it typically does in a given year. El Niño events tend to increase the amount of storminess in areas just north and south of the equator, and these tropical thunderstorms, if given the right encouragement from the atmosphere, can start to organize, take on some rotation and intensify into a fledgling tropical cyclone. The other factor at work is a global weather cycle known as the Madden-Julian Oscillation, or MJO. Named after meteorologists Roland Madden and Paul Julian, who first described the cycle in 1971, the MJO is an eastward-moving disturbance of clouds, rainfall, winds and pressure that circles the globe in about 30 to 60 days, according to the National Oceanic and Atmospheric Administration (NOAA). The MJO has two phases, an enhanced rainfall phase and a suppressed rainfall phase. Recently, the central and western Pacific entered into a particularly strong enhanced rainfall phase, after being in a six-week suppressed phase. The enhanced rainfall phase favors increased thunderstorm activity across the ocean basin, resulting in more tropical cyclones.
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