NASA Sees Tropical Storm Rumbia Hit China With Heavy Rainfall
Typhoon Rumbia had weakened to a tropical storm and moved over southern China when NASA’s TRMM satellite flew above on July 2, 2013 at 0316 UTC and measured its rainfall rates. [image-78]
An analysis of rainfall from TRMM Microwave Imager (TMI) and Precipitation (PR) data shows that Rumbia was dropping rain at a rate of over 92mm/hour (~3.6 inches) in areas of southern China near the Gulf of Tonkin. An intense but narrow feeder band near Hong Kong is shown streaming heavy rainfall into China from the South China Sea.
An image showing a 3-D slice through of tropical storm Rumbia was created at NASA’s Goddard Space Flight Center in Greenbelt, Md. using TRMM Precipitation Radar data. Those data showed that the thunderstorms near Rumbia's center of circulation were then reaching heights mainly below 13 km (~8.1 miles). Some powerful thunderstorms in the feeder band near Hong Kong were found to reach to heights of 15 km (~9.3 miles).
Just before TRMM flew overhead, Tropical storm Rumba had made landfall over southeastern China on July 2, 2013 at 0300 UTC (July 1 at 11 p.m. EDT). The storm was 231 miles east of Hanoi, Vietnam near 21.4 north and 110.0 east. Rumbia’s maximum sustained winds were near 50 knots (57 mph/92 kph) and dropping.
According to the Joint Typhoon Warning Center, radar imagery from Haikou, China at 0300 UTC (July 1 at 11 p.m. EDT), showed that the tightly-curved banding of thunderstorms became less organized, and had weakened.
On July 2, China’s National Meteorological Centre (NMC) issued a blue category warning of typhoon at 6:00 p.m. (Beijing Time). The blue category warning means strong winds are expected along coastal Guangxi, and Beibu Gulf. Central and western Guangxi and southern Yunnan can expect heavy rainfall and gusty winds. In central Guangxi, there will be isolated areas of heavy rainfall as high as (100-120 mm/4.0 to 4.7 inches).
According to the NMC, “Severe tropical storm Rumbia has weakened into a tropical storm at 12:00 [p.m. local time] today. At 17:00 (5 p.m. local time), it was centered over Laibin city of Guangxi Zhuang Autonomous region (23.4°N, 109.0°E ) with maximum wind force up to scale 8 (18 meters/second) [64 kph/40 mph].”
Rumbia was moving to the northwest at 11 knots (12.6 mph/20 kph) and is expected to dissipate over China in the next day or two.
NASA’s Goddard Space Flight Center
July 1, 2013 - NASA Sees Heavy Rainfall as Typhoon Rumbia Heads for Landfall in China
Typhoon Rumbia developed from a low pressure area east of the Philippines and crossed the country from east to west before moving into the South China Sea. NASA’s TRMM satellite flew over Rumbia as it nears southeastern China and identified areas of heavy rainfall in the southern quadrant of the storm.[image-51]
On Sunday, June 30, NASA infrared satellite imagery revealed tightly curved bands of thunderstorms over the southern quadrant of the storm were wrapping into the northern quadrant of the low-level center. However, in the northwestern quadrant, the quadrant that will make landfall first, there was a lack of strong convection and thunderstorms. Those satellite observations held true 24 hours later.
Typhoon Rumbia was located east of Hainan Island, China in South China Sea early on July 1. It is headed for landfall today, July 1, in southeastern China, south of Hong Kong.
When NASA’s Tropical Rainfall Measuring Mission or TRMM satellite flew over Rumbia on July 1 at 0412 UTC (12:12 a.m. EDT) the Precipitation Radar instrument noticed some areas of heavy rainfall in bands of thunderstorms south of the center of circulation. Heavy rainfall was falling at rates of over 2 inches/50 mm per hour. TRMM imagery continued to show the strong band of thunderstorms continued wrapping around the southern quadrant of the storm and into the low-level center.
On July 1 at 1500 UTC (11 a.m. EDT), Rumbia’s maximum sustained winds increased from 45 knots (52 mph) to 65 knots (74 mph/120 kph) making it a minimal typhoon. It was located near 20.3 north latitude and 110.9 east longitude, about 217 nautical miles southwest of Hong Kong. Rumbia is moving to the west-northwest at 13 knots (15 mph/24 kph).
Rumbia’s western quadrant is already interacting with the land of Hainan Island, China, breaking up the band of thunderstorms in that part of the storm. Because the interaction with land is already weakening the storm the forecasters at the Joint Typhoon Warning Center (JTWC) expect Rumbia to continue to weaken as it heads for landfall.
JTWC expects that Rumbia may make landfall near Zhanjiang, a prefecture-level city at the southwestern end of Guangdong province. Areas that Rumbia’s center are expected to pass near include Leizhou Bay and Zhanjiang Port.
Residents along southeastern China are already feeling the effects of Rumbia with tropical-storm force winds, heavy rainfall, flash flooding and very rough surf along the coasts.
NASA’s Goddard Space Flight Center