By:
Jeff Masters
, 4:06PM,GMT on July 7,2016
Figure 1. Radar image of Super Typhoon Nepartak taken at 11:30 am EDT July 7, 2016 (11:30 pm local time in Taiwan.) Image credit: http://www.cwb.gov.tw/V7e/observe/radar/>Taiwan CWB.
Figure 2. MODIS visible satellite image of Super Typhoon Nepartak at 02:30 UTC July 7 (10:30 pm EDT July 6), 2016. At the time, Nepartak was a Category 5 super typhoon with 175 mph winds. Image credit: NASA.
Figure 3. Buoy NTU2 (located about 170 km southeast of Taitung, Taiwan) recorded a surface pressure of approximately 897 mb as the eye passed over between 7:50 - 8:20 am EDT Thursday. Image credit: Institute of Oceanography, Taiwan National University. Thanks go to Brian McNoldy and WU member Carnivorous for these links.
Nepartak's impact on Taiwan and China
Nepartak had slowed down to a west-northwest motion at 10 mph on Thursday morning (U.S. EDT), and the typhoon will make landfall in the southern positron of Taiwan later on Thursday. Passage over the high mountains of Taiwan will significantly disrupt Nepartak, and the typhoon is likely to make a second landfall in mainland China on Saturday as a tropical storm.
About 1 - 2" of rain has fallen over Taiwan during the past ten days, so the soils should be able to absorb some of the expected 5 - 15" of rain Nepartak will dump over much of the island. Nevertheless, damaging flooding from the torrential rains of Super Typhoon Nepartak will likely cause tens of millions of dollars in damage to agriculture in Taiwan. The bigger concern for heavy rainfall from Nepartak is in mainland China, though. Exceptionally heavy monsoon rains affected large portions of central and eastern China over the past ten days, bringing rampaging floods that killed at least 140 people since June 30 and caused billions in damage. The soils are still saturated from these rains, and Nepartak's rains will trigger additional damaging flooding. The largest city in central China--Wuhan, with a population of 10.8 million--received over 560 mm (1.8 feet) of rain over the past ten days, with an additional 7.09” (180 mm) of rain falling in the twelve hours ending at 8 am July 6, causing widespread chaos there. However, the Thursday morning run of the HWRF model (Figure 5) showed the heaviest rains of Nepartak would likely remain south of the area flooded by last week's rains.
Figure 4. A stadium in Wuhan, China on July 6, 2016, after the city received 7.09” (180 mm) of rain in the twelve hours ending at 8 am July 6. Wuhan received over 560 mm (1.8 feet) of rain over the ten day period before yesterday's deluge, causing widespread damage and chaos. (Photo by Wang He/Getty Images)
Figure 5. Swath of total rainfall from Nepartak as predicted by the 06 UTC (2 am EDT) Thursday, July 7, 2016 run of the HWRF model. The model predicted widespread rains of 8 - 16" (light yellow colors) over much of Taiwan and Eastern China. Image credit: NOAA/NCEP/EMC.
Figure 6. Rainfall for the 10-day period ending on July 6, 2016 over China. Rainfall amounts in excess of 15.75" (400+ mm, dark blue color) fell over a large swath of China from Wuhan to just west of Shanghai. Image credit: National Meteorological Center of CMA.
Taiwan's recent typhoon history
Only one typhoon has hit Taiwan at Category 5 strength since accurate satellite records began in the 1970s: Super Typhoon Bilis, which intensified from a Category 2 storm with 105 mph winds to a Category 5 storm with 160 mph winds in the 30 hours before making landfall on the island on August 22, 2000. Bilis killed 14 people and did $134 million in damage to Taiwan. The island was hit by two major typhoons last year: Category 4 Typhoon Dujuan and Category 3 Typhoon Soudelor. Typhoon Dujuan made landfall on the island on September 28, 2015, with 140 mph winds, killing three, injuring 376, but causing less than $10 million in damage. Dujuan brought heavy rains to eastern China that caused $652 million in damage, but did not kill anybody there. On August 7, 2015, Typhoon Soudelor hit Taiwan as a Category 3 storm with 120 mph winds. Souledor killed eight, injured 420, and caused over $100 million in damage. At the peak of the storm, 4.85 million households lost electricity--the largest blackout on record in Taiwan due to a typhoon (previous record: 2.79 million customers blacked out by Typhoon Herb in 1996.) Taiping Mountain in eastern Taiwan's Yilan County saw the heaviest rains from the typhoon, with accumulations peaking at 1,334 mm (52.52".) Souledor brought heavy rains to eastern China that killed 26 people and caused $3.08 billion in damage. The Central Weather Bureau of Taiwan has a list (in Chinese) of all the typhoons that have affected Taiwan.
Nepartak: Earth's third Category 5 storm of 2016
Nepartak is the third Category 5 storm on Earth so far in 2016. Its 900 mb minimum surface pressure makes it the strongest tropical cyclone of the year (by pressure), and its peak 175 mph winds are tied for the second strongest winds of the year. The other two Category 5 storms earlier this year were in the Southern Hemisphere: the Southwest Indian Ocean's Tropical Cyclone Fantala, which topped out with 175 mph winds and a 910 mb central pressure on April 17, and the Southeast Pacific's Tropical Cyclone Winston, which devastated Fiji on February 20 with sustained winds of 180 mph. Winston's lowest central pressure was 915 mb. Both storms were tied for the strongest tropical cyclones ever observed (by sustained winds) in their respective ocean basins. On average, Earth sees 4 - 5 Category 5 storms per year, with over 50% of these being typhoons in the Northwest Pacific. It is rare to have the first named storm of the year in an ocean basin make it to Category 5 strength. This has happened at least once before in the Northwest Pacific--in 1958, when Category 5 Super Typhoon Ophelia formed in January. The Atlantic has had two cases where the first named storm of the year made it to Cat 5--Hurricane Allen in 1980, and Hurricane Andrew in 1992 (thanks go to WU member Tcwx2 for reminding me of Andrew).
Nepartak Links
Storm Chaser James Reynolds' Twitter feed is documenting Nepartak's landfall from Taitung, Taiwan, near where the eye is expected to make landfall.
Storm Chaser Josh Morgerman of iCyclone is also reporting from Taitung.
Brian McNoldy has a continuously updating radar loop of Nepartak.
Stunning visible animation of Nepartak from July 7, 2016, from NOAA/RAMMB/Colorado State.
Stunning visible animation of Nepartak from July 6, 2016, from NOAA/RAMMB/Colorado State.
The Himawari-8 Floater satellite loops have some impressive animations of Nepartak during daylight hours in the Western Pacific.
Eastern Taiwan observations from CWB. A Taiwanese station to follow is the Ludao on Green Island (which lies directly in the path of Nepartak). Thanks go to WU member Carnivorous for this link.
Figure 7. VIIRS visible satellite image of Hurricane Blas taken at 21:55 UTC (5:55 pm EDT) July 6, 2016. At the time, Blas was a Category 3 storm with 125 mph winds. Image credit: NASA.
Eastern Pacific remains active
The Eastern Pacific, which got off to its second slowest start on record on July 2 when Tropical Storm Agatha formed, now has two more tropical cyclones. Hurricane Blas, which spun into life on July 3 about 700 miles south of the southern tip of the Baja Peninsula, peaked as a Category 4 storm with 140 mph winds at 11 pm EDT July 6. Blas is headed west-northwest into a region with cool waters and more stable air, and will dissipate early next week without affecting any land areas. Tropical Depression 4-E, soon to become Tropical Storm Celia, is one Hawaii should keep an eye on, though Celia will have trouble with the wake of cold water left behind by Blas. And we could have Tropical Storm Darby next week: both the European and GFS models show an area of disturbed weather will develop several hundred miles southwest of the coast of Mexico early next week, and will intensify into a tropical storm late next week. In their 8 am EDT Thursday Tropical Weather Outlook, NHC gave this future disturbance 2-day and 5-day odds of development of 0% and 20%, respectively.
The Atlantic is asleep
There are no tropical cyclone threat areas in the Atlantic to discuss today, and none of the reliable models for tropical cyclone formation is predicting development during the coming five days. Much of the tropical North Atlantic is dominated by a large area of dry air and dust from the Sahara Desert, which is common in early July.
I'll have a new post on Friday.
Jeff Masters
No comments:
Post a Comment