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Hurricane Season 2011: Tropical Storm Haima (Western Pacific Ocean)
06.27.11
 
Haima has regained minimal tropical storm status with some powerful thunderstorms south of its center. › View larger image
NASA's Aqua satellite passed over Haima on June 23 at 06:23 UTC (2:23 a.m. EDT) when its center was near Hainan Island, China. At that time, most of its heaviest thunderstorms (purple) were over the waters of the South China Sea, dropping rain at 2 inches/50 mm per hour.
Credit: NASA/JPL, Ed Olsen
Tropical Storm Haima Makes Landfall in Vietnam

Tropical Storm Haima made landfall in Vietnam this weekend.

Vietnam's Central Steering Committee for Flood and Storm Prevention and Control reported to Bernama.com that the storm caused 16 deaths from heavy rainfall. NASA infrared satellite data had revealed strong thunderstorms containing heavy rainfall around Haima's center of circulation on Friday, June 24, 2011, while the storm was still at sea. Rainfall rates were as high as 2 inches (50 mm) per hour in those strong thunderstorms.

The central province called Thanh Hoa is working to recover from the flooding rainfall by pumping floodwaters from fields, while Nghe An is recovering from flash flooding.

Text credit: Rob Gutro, NASA's Goddard Space Flight Center, Greenbelt, Md.





June 24, 2011

Haima has regained minimal tropical storm status with some powerful thunderstorms south of its center. › View larger image
NASA's Aqua satellite passed over Haima on June 23 at 06:23 UTC (2:23 a.m. EDT) when its center was near Hainan Island, China. At that time, most of its heaviest thunderstorms (purple) were over the waters of the South China Sea, dropping rain at 2 inches/50 mm per hour.
Credit: NASA/JPL, Ed Olsen
NASA Sees Tropical Storm Haima Poised For Vietnam Landfall

NASA satellite imagery revealed that Haima has regained minimal tropical storm status with some powerful thunderstorms south of its center. Haima is moving west through the Gulf of Tonkin in the South China Sea between Hainan Island and Vietnam and is expected to bring heavy rains to Vietnam this weekend.

On June 24. 2011 at 0600 UTC (2 a.m. EDT), Tropical Storm Haima's winds were back up to 35 knots (40 mph/65 kmh) making it a minimal tropical storm. Haima is headed west-southwest at 10 knots (11 mph/19 kmh). Its center was near 20.3 North and 107.0 East about 90 nautical miles east-southeast of Hanoi, Vietnam.

Hanoi, Vietnam is north of where Haima is expected to make landfall and has been experiencing light rains from the western-most fringe of the tropical storm. On June 24 at 9 a.m. EDT, Hanoi had mostly cloudy skies and light rain with winds from the north at 16 mph. The temperature was 80 Fahrenheit (27 Celsius) and the minimum central pressure was 993 millibars (and dropping).

NASA's Aqua satellite passed over Haima on June 23 at 06:23 UTC (2:23 a.m. EDT) when its center was near Hainan Island, China. At that time, most of its heaviest thunderstorms were over the waters of the South China Sea, dropping rain at 2 inches/50 mm per hour. The Atmospheric Infrared Sounder (AIRS) instrument data showed a small area of strong convection and thunderstorms mostly south of the center of circulation. Because infrared imagery shows temperature, it revealed that those thunderstorms had cold cloud top temperatures as cold as or colder than -63 Fahrenheit (-52 Celsius). On June 24, a microwave satellite image confirmed that the strongest convection and thunderstorms remained over the south of the center.

The warm waters of the Gulf of Tonkin have helped to reinvigorate Haima. Warm waters over 80F (26.5C) provide energy for a tropical cyclone. The waters in the Gulf of Tonkin are near 89.5F (32C).

The other factor that is critical in the strength of a tropical cyclone is wind shear. Strong wind shear can batter a storm and tear it apart. Current wind shear in the vicinity of Haima is between 15 and 20 knots (17-23 mph/27-37 kmh) and is expected to remain at that level through Haima's landfall in Vietnam tomorrow. That wind shear will help keep Haima from strengthening into a cyclone, although the Joint Typhoon Warning Center noted that it is expected to make landfall as a marginal tropical storm before dissipating over land.

Text credit: Rob Gutro, NASA's Goddard Space Flight Center, Greenbelt, Md.



June 23, 2011

AIRS captured this infrared image of Haima and Meari on June 22 at 17:53 UTC 1:53 p.m. EDT. › View larger image
NASA's Aqua satellite captured this infrared image of 2 tropical cyclones from the AIRS instrument on June 22 at 17:53 UTC 1:53 p.m. EDT. The heaviest rainfall and strongest convection from Tropical Storm Meari (right) is currently over the Philippine Sea. The strongest thunderstorms (purple) in Haima (left) are mostly over the South China Sea and Hainan Island, China.
Credit: NASA/JPL, Ed Olsen
NASA Satellite Gets 2 Tropical Cyclones in 1 Shot

The Northwestern Pacific Ocean is active with two tropical cyclones today, Tropical Storm Meari near the Philippines, and Tropical Depression Haima moving over China and now toward Vietnam. NASA's Aqua satellite passed over the region on June 22 and captured an infrared image of both storms in one image.

One of the instruments onboard NASA's Aqua satellite is the Atmospheric Infrared Sounder (AIRS). AIRS captures cloud top temperatures in tropical cyclones to determine the strength of convection and thunderstorms. The strongest thunderstorms have cloud tops with icy cold temperatures of -63F/-52C and are indicative of areas where rainfall rates could reach up to 2 inches / 50 mm per hour and both Meari and Haima had large areas of those very cold cloud top temperatures.

AIRS captured the image on June 22 at 17:53 UTC 1:53 p.m. EDT and it showed the heaviest rainfall and strongest convection (rapidly rising air that forms the thunderstorms that power a tropical cyclone) from Tropical Storm Meari is currently over the Philippine Sea and skirting the east coast of Luzon. The imagery showed the large area of strong thunderstorms (and convection) in Haima mostly over the South China Sea and Hainan Island, China.

Haima is still a tropical depression as its maximum sustained winds on June 23 at 1500 UTC (11 a.m. EDT) were near 30 knots (34 mph/55 kmh). Tropical storms have maximum sustained winds between 38 and 73 mph. It was located over Hainan Island, China, and about 235 nautical miles west-southwest of Hong Kong, China near 21.4 North and 109.6 East. Tropical Depression Haima is moving westward at 10 knots (11 mph/19 kmh).

The Joint Typhoon Warning Center does not expect Haima to strengthen into a tropical storm because of its interaction with land over Hainan Island, and its short track over the South China Sea between there and Vietnam where it is expected to make its final landfall. An orange alert in now in effect for North and South Korea as Tropical Depression Haima is tracking in that direction.

Meari is a tropical storm, and has maximum sustained winds near 40 knots (46 mph/78 kmh). It is centered to the east of Luzon, the Philippines and about 500 nautical miles south-southwest of Kadena Air Base, Japan. Meari is moving to the northwest at 12 knots (14 mph/22 kmh).

The Joint Typhoon Warning Center noted that Meari's center of circulation is elongated and there are "multiple minor vorticies developing and rotating cyclonically around the center." During the morning hours on June 23, AIRS data and microwave satellite data showed that convection has consolidated around the center, helping to better pinpoint the center in this massive storm system.

As Meari continues on a northward track it will run into cooler sea surface temperatures in the Yellow Sea, they will weaken the tropical storm quickly.

Meari's center is forecast now to remain at sea and brush Taiwan, eastern China and make landfall in the southwestern area of North Korea this weekend.

Text credit: Rob Gutro, NASA's Goddard Space Flight Center, Greenbelt, Md.



June 22, 2011

This AIRS image shows most of the strongest thunderstorms (purple) in Haima are south of the center of circulation. › View larger image
Tropical Depression Haima's (center) cold thunderstorm cloud tops were captured on this infrared image from NASA's AIRS instrument on June 22 at 05:41 UTC (1:41 a.m. EDT). AIRS flies on NASA's Aqua satellite. This image shows most of the strongest thunderstorms (purple) in Haima are south of the center of circulation and none on the northern side. The eastern edge of Tropical Storm Meari is located to the far right near Luzon.
Credit: NASA/JPL, Ed Olsen
NASA Sees Heavy Rainfall on Southern Side of Tropical Depression Haima as it Nears Hong Kong

Tropical Depression Haima, formerly known as 06W continues moving toward Hong Kong and NASA infrared satellite imagery shows strong rain-making thunderstorms in the southern quadrant of the storm. Rainfall is something that a rain-weary China doesn't need, so preparations are being made now.

Heavy rainfall is expected as Haima approaches in southern Taiwan, and also in southern areas of China's Fujian and Guangdong provinces, and Hainan Island. That heavy rainfall was spotted on an infrared image captured by NASA's Atmospheric Infrared Sounder (AIRS) instrument on June 22 at 05:41 UTC (1:41 a.m. EDT). AIRS flies on NASA's Aqua satellite. This image showed that most of the strongest thunderstorms in Tropical Depression Haima were south of the center of circulation and none are on the northern side. The cloud top temperatures in those thunderstorms were colder than the -63 degree Fahrenheit/-52 Celsius threshold on AIRS data, indicating they are very high, cold cloud tops and likely harbor heavy rainfall (about 2 inches/50 mm per hour).

AIRS data also shows that Haima is not well organized. One interesting feature that appeared on multispectral satellite imagery was that Haima has "multiple surface circulation center orbiting within the broad overall circulation," according to the Joint Typhoon Warning Center (JTWC). Almost like smaller low pressure areas in the larger low pressure area.

In anticipation of Haima, the Deccan Herald on-line reported that passenger ship operations in the south Qiongzhou Strait have already been suspended. Airline flights were also suspended yesterday and again today from the Meilan International Airport in Haikou.

On June 22 at 1500 UTC (11 a.m. EDT), Haima's maximum sustained winds were down to 25 knots (29 mph/46 kmh). It was still 145 nautical miles southwest of Hong Kong, near 20.9 North and 111.8 East. Haima is moving to the northwest at 7 knots (8 mph/13 kmh).

Strong wind shear between 20 and 30 knots (23 and 36 mph/37 and 55 kmh) continues to batter Haima, so the JTWC doesn't expect any strengthening before it makes landfall in China.

Text credit: Rob Gutro, NASA's Goddard Space Flight Center, Greenbelt, Md.



June 21, 2011

AIRS captured this infrared image of 06W on June 20 at 18:05 UTC when it was still a tropical storm. › View larger image
NASA's AIRS instrument on the Aqua satellite captured this infrared image of 06W on June 20 at 18:05 UTC (2:05 p.m. EDT) when it was still a tropical storm. The purple areas represent icy cold temperatures of -63F/-52C and high, strong thunderstorms. The storm has weakened and appears much more disorganized today.
Credit: NASA/JPL, Ed Olsen
Infrared NASA Imagery Reveals a Weaker Tropical Cyclone in the South China Sea

Tropical Depression 06W is still slowing, making its way through the South China Sea today and has weakened overnight. NASA infrared satellite imagery showed a much more disorganized storm with scattered convection, which accounts for its weakened status from tropical storm to tropical depression.

On June 21 at 1500 UTC (11 a.m. EDT) the newly weakened Tropical Depression 06W was located about 480 nautical miles east-southeast of Hanoi, Vietnam near 18.8 North and 113.8 East. Depression 06W's maximum sustained winds had decreased to 25 knots (28 mph/46 kmh). It was moving west-southwest at 9 knots (10 mph/17 kmh) and kicking up 11 foot-high waves in the South China Sea.

NASA's Atmospheric Infrared Sounder (AIRS) instrument that flies on the Aqua satellite captured an infrared image of 06W on June 20 at 18:05 UTC (2:05 p.m. EDT) when it was still a tropical storm. Since then, convection has become more scattered and winds have lessened. In addition, the low level center of the storm's circulation has become elongated due to wind shear. Elongation of a tropical cyclone is a sign of weakening.

Because of that wind shear, 06W is expected to barely maintain tropical depression strength before it makes landfall on Thursday, June 23 near Jhan Jiang, China.

The AIRS infrared image captures cloud top temperatures and the coldest temperatures appeared south of the center of circulation. Those cold cloud top temperatures represented the strongest thunderstorms in the tropical storm where rainfall rates could reach up to 2 inches / 50 mm per hour.

Because Tropical Depression 06W has begun moving to the west-southwest, the Joint Typhoon Warning Center has changed the forecast track and taken the depression farther south. The current landfall takes 06W just north of Hainan Island, China and then onto the mainland at the southwestern end of Guangdong province of Southern China.

Text credit: Rob Gutro, NASA's Goddard Space Flight Center, Greenbelt, Md.



June 20, 2011

NASA's AIRS infrared image showed strong storms mostly to the south of the center of circulation (purple). › View larger image
NASA's Aqua satellite passed over Tropical Storm 06W on June 20 at 05:53 UTC (1:53 a.m. EDT). NASA's AIRS infrared image showed strong thunderstorms mostly to the south of the center of circulation (purple).
Credit: NASA/JPL, Ed Olsen
NASA Satellite Sees Tropical Storm 06W Headed for South China Landfall

NASA Satellite imagery today shows strong convection has increased within slow-moving Tropical Storm 06W as it moves through the South China Sea and toward a landfall in southeastern China later this week.

When NASA's Aqua satellite passed over Tropical Storm 06W early on June 20 at 05:53 UTC (1:53 a.m. EDT) the infrared data sent back to NASA from the Atmospheric Infrared Sounder (AIRS) instrument showed that convection (rapidly rising air that forms the thunderstorms that make up a tropical cyclone) had increased over the warm waters of the South China Sea.

According to the Joint Typhoon Warning Center (JTWC), most of that convection appears south of the center of circulation as a result of southwesterly winds blowing toward the storm's center. However, that center of circulation is somewhat difficult to pinpoint on the infrared image as the tropical storm appears to be somewhat elongated.

Satellite data did reveal that the low level center of circulation is partially exposed to outside winds, which could weaken the storm before landfall later today or tomorrow.

At 1500 UTC (11 a.m. EDT), Tropical Storm 06W has maximum sustained winds near 35 knots (40 mph/65 kmh) and is moving to the west near 9 knots (10 mph/17 kmh). It is centered about 250 nautical miles east-southeast of Hong Kong, China near 20.6 North and 117.7 East.

The JTWC forecasts that Tropical Storm 06W will continue tracking westward over the next two days while being pushed by easterly winds. There is some vertical wind shear battering the storm at 15 knots (17 mph/28 kmh), and that is expected to increase as the storm nears the coast. However, 06W is expected to maintain tropical storm strength at least until landfall.

Tropical Storm conditions are expected in Hong Kong on Tuesday, Wednesday and Thursday as slow moving Tropical Storm 06W moves toward the city. Residents should prepare for heavy rainfall and flooding.

Text credit: Rob Gutro, NASA's Goddard Space Flight Center, Greenbelt, Md.



June 17, 2011

NASA Satellite Sees Tropical Depression 06W Near the Philippines

image of 06W › View larger image
TRMM captured the rainfall rates of TD06W on June 16 at 2130 UTC 5:30 p.m. EDT). The heaviest rainfall appears on the northwestern and southeastern sides of the depression. The yellow and green areas indicate moderate rainfall between .78 to 1.57 inches per hour. Red areas are heavy rainfall at almost 2 inches per hour.
Credit: NASA/SSAI, Hal Pierce
The sixth western Pacific tropical cyclone (06W) of 2011 has developed near the Philippines and the Tropical Rainfall Measuring Mission (TRMM) satellite saw some heavy rainfall in the storm. Tropical Depression 06W was dropping the heaviest rain over the open waters of the Western North Pacific Ocean on June 17 as the storm continues to move toward China.

The TRMM satellite is operated by the Japanese Space Agency and NASA, and continually monitors the tropics and measures rainfall in tropical cyclones. TRMM captured an early morning look at the forming depression on June 16, 2011 at 2130 UTC (5:30 p.m. EDT). A precipitation analysis from TRMM's Microwave Imager (TMI) and Precipitation Radar (PR) showed that Tropical Depression 06W wasn't well organized but contained areas of moderate to heavy rainfall located east of the Philippines.

The heaviest rainfall appears on the northwestern and southeastern areas of the depression. Most of the rainfall is moderate falling at a rate between .78 to 1.57 inches (20 and 40 mm) per hour. The isolated areas of heavy rain over ocean areas are falling at about 2 inches (50 mm) per hour.

The Philippines have already received a lot of rain from tropical cyclones this season. Tropical storm Aere, Super Typhoon Songda and Tropical Storm Sarika have already affected the Philippines this year.

Now, Tropical Depression 06W threatens even more rainfall. On June 17 at 1500 UTC (11 a.m. EDT) Tropical Depression 06W had maximum sustained winds near 25 knots. It was located about 430 nautical miles east-southeast of Manila, Philippines near 12.1 North and 127.6 East. It was moving to the northwest near 13 knots.

Tropical Depression 06W is expected to intensify to a tropical storm, skirt the eastern coast of the Philippines and head toward Taiwan over the next five days. During the middle part of the week of June 19, Tropical Depression 06W is expected to make landfall in southeastern China.

Text credit: Rob Gutro and Hal Pierce, NASA's Goddard Space Flight Center, Greenbelt, Md.