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Hurricane Season 2009: Linfa (Pacific)
06.23.09
 
June 23, 2009

NASA's Aqua satellite captured this view of Linfa's clouds on June 23 over southeastern China > Larger image NASA's Aqua satellite captured this view of Linfa's clouds on June 23 over southeastern China
Credit: NASA JPL, Ed Olsen
Southeastern China Soaked by Cyclone Linfa, Now a Remnant Low

Southeastern China was ravaged by Cyclone Linfa this week and the storm is now an area of low pressure. The storm made landfall at 8:30 a.m. local time in the Dongshi Township, Jin jiang City in the Fujian Province on Sunday, June 19. At that time, it came ashore with sustained winds near 51 mph, making it a tropical storm upon landfall.

Linfa brought drenching rains that caused landslides. Reports indicate several deaths and a number of people missing as a result of landslides in eastern and southern China provinces.

The Shanghai Daily News reported that the storm triggered an evacuation of 130,000 people from the Fujian Province. Tropical Storm Linfa flooded 32,000 hectares of cropland. One hundred houses were reported destroyed from the storm.

The Atmospheric Infrared Sounder (AIRS) instrument on NASA's Aqua satellite captured an infrared image of Linfa's cold clouds and rains (blue area over eastern China) as it was moving offshore and dissipating on June 23 at 12:17 a.m. EDT (4:17 UTC).

The infrared image shows Linfa's cold thunderstorm clouds in blue. The blue areas are around 240 degrees Kelvin, or minus 27F. The colder the clouds are, the higher they are, and the more powerful the thunderstorms are that make up the cyclone.

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



June 22, 2009

NASA's TRMM satellite captured Linfa's rainfall while on the China coast on June 22 > Larger image NASA's TRMM satellite captured Linfa's rainfall while on the China coast on June 22.
Credit: NASA/SSAI, Hal Pierce
NASA's TRMM satellite captured Linfa's rainfall on June 20 as it was approaching southeastern China > Larger image NASA's TRMM satellite captured Linfa's rainfall on June 20 as it was approaching southeastern China. Credit: NASA/SSAI, Hal Pierce
At 1:25 a.m. EDT on June 20, NASA's MODIS instrument saw Tropical Cyclone Linfa approaching China > Larger image At 1:25 a.m. EDT on June 20, NASA's MODIS instrument saw Tropical Cyclone Linfa approaching China. Credit: NASA MODIS Rapid Response
NASA Satellites Catch Cyclone Linfa's Death Knell

Tropical Depression Linfa's death knell has been sounded. The Joint Typhoon Warning Center issued their final advisory on the storm on June 22. At 11 a.m. EDT the depression was about 320 nautical miles west-northwest of Okinawa, Japan. That put it near 28.0 north and 122.6 east. Sustained winds were down to 23 mph (20 knots) and fading.

Earlier in the day on Monday, June 22, Linfa touched the land on the southeastern coast of China. Land interaction always weakens a tropical cyclone and this brush with China was no different. NASA's Tropical Rainfall Measuring Mission (TRMM) satellite and NASA's Aqua satellite caught good looks at the storm's rainfall and cloud formation.

Cyclone Linfa weakened to tropical storm strength even before hitting the southeastern coast of China. It did, however, cause heavy rainfall and some flooding in east China's Fujian Province. TRMM captured an image of Linfa's rainfall on June 22 at 0319 UTC (or June 21 at 11:19 p.m. EDT). At that time, Linfa had weakened to a tropical depression with sustained wind speeds of about 35 mph (30 knots). Past and forecast positions of Linfa were overlaid on this TRMM rainfall analysis image.

On June 20, Tropical storm Linfa was upgraded to minimal cyclone with wind speeds of 65 knots (~75 miles per hour). The Joint Typhoon Warning Center forecast indicated that it would move closer to the southeast coast of China than predicted earlier, and that it would have sustained winds up to 75 knots (~86 miles per hour). The TRMM satellite captured Linfa's rainfall on June 20 at about (1:13 a.m. EDT) 0513 UTC on its way to southeastern China. The image clearly reveals an eye. The image was created by the TRMM precipitation analysis which used data from TRMM's Microwave Imager (TMI) and Precipitation Radar (PR) instruments.

Also on June 20, NASA's Aqua satellite flew over Linfa about ten minutes after TRMM captured its rainfall. Aqua soared about Linfa at 0525 UTC (1:25 a.m. EDT) and captured a stunning image of its cloud formation, using the Moderate Imaging Spectroradiometer. In the image, China is to the top left, and the island of Taiwan is to the top right.

Although the final warning has been issued on the storm, it will still be watched for regeneration.

Text credit: Hal Pierce, Goddard Space Flight Center/SSAI and Rob Gutro, NASA's Goddard Space Flight Center



Linfa's thunderstorms (in blue and purple) are seen as an amorphous shape off the east China coast in this Aqua satellite AIRS image. > Larger image Linfa's thunderstorms (in blue and purple) are seen as an amorphous shape off the east China coast in this Aqua satellite AIRS image. Credit: NASA JPL, Ed Olsen Eastern China Gets a Tropically Depressed "Kiss" From Linfa

When you look at an infrared satellite image from NASA's Aqua satellite taken on June 21, you would see that the western side of Cyclone Linfa "kissed" the eastern China coast and is now moving toward Japan.

On June 22 at 5 a.m. EDT (0900 UTC), Linfa was 400 miles west of Okinawa, Japan near 26.8 north and 120.3 west. By 2 a.m. EDT on June 22, Linfa had already crossed the Chinese coast and moved into the East China Sea. Maximum sustained winds were near 30 knots (34 mph) meaning it's now a tropical depression.

Linfa is currently in an area of low to moderate wind shear, winds blowing at different levels of the atmosphere in different directions that can weaken a storm. It is expected to weaken further as a result of staying in that kind of harsh environment. As a result, even though its center moved back into warm waters, the wind shear will lead to its dissipation by June 24.

The Atmospheric Infrared Sounder (AIRS) instrument on NASA's Aqua satellite captured an infrared image of the low pressure area on June 21 at 4:35 p.m. EDT (8:35 UTC. In the infrared image, Linfa's cold clouds (in purple) resemble "blob" instead of being rounded (which would indicate a stronger organized storm). The storm's lowest temperatures (in purple) are associated with high, cold cloud tops. Those temperatures are as cold as or colder than 220 degrees Kelvin or minus 63 degrees Fahrenheit (F). The blue areas are around 240 degrees Kelvin, or minus 27F.

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



June 19, 2009

NASA's TRMM satellite captures Cyclone Linfa's rainfall from space in this image. NASA's TRMM satellite captures Cyclone Linfa's rainfall from space in this image.
> Larger image
Credit: NASA/SSAI, Hal Pierce
Tropical Storm Linfa Threatens Taiwan and Mainland China

Tropical storm Linfa is expected to cause heavy rainfall and possible flooding as it approaches southwestern Taiwan and southeastern China over the weekend of June 20-21.

When the Tropical Rainfall Measuring Mission (TRMM) satellite passed above Linfa on June 19, 2009 at 2:10 a.m. EDT (0610 UTC) it captured an image of the storm's rainfall. The image also shows the projected path of Linfa over the next couple of days (the 19 means June 19, and the 20 means June 20. The "Z" number represents Zulu Time or UTC).

Linfa had sustained winds of about 50 knots (~58 miles per hour) speeds at that time and is predicted by the Joint Typhoon Warning Center to strengthen slightly without attaining typhoon strength before hitting Taiwan. The rainfall analysis uses data from the TRMM Microwave Imager (TMI) and the Precipitation Radar (PR) instruments and is overlaid on an image that is a combination of TRMM Visible and Infrared (VIRS) images.

Merged satellite rainfall and rainfall prediction models indicate that rainfall may exceed 200 millimeters ( ~4 inches) over Taiwan with the passage of Linfa.

On June 19 at 11 a.m. EDT, Linfa was located about 725 nautical miles southwest of Okinawa, Japan near 19.5 north and 117.4 east. It had sustained winds near 57 mph (50 knots). Currently, Linfa is moving northeast, and is expected to pass between mainland China and Taiwan.

Text credit: Hal Pierce, Goddard Space Flight Center/SSAI



June 18, 2009

NASA/JAXA's TRMM satellite captured the rain falling within Cyclone Linfa as it passed overhead in space on June 18.NASA/JAXA's TRMM satellite captured the rain falling within Cyclone Linfa as it passed overhead in space on June 18.
> Larger image
Credit: NASA/SSAI, Hal Pierce
NASA's AIRS instrument captured this infrared view of Cyclone Linfa's frigid clouds, seen here in purple.NASA's AIRS instrument captured this infrared view of Cyclone Linfa's frigid clouds, seen here in purple.
> Larger image
Credit: NASA JPL, Ed Olsen
Tropical Storm Linfa Headed to Southeastern Taiwan

Storm 03W has intensified into Tropical Storm Linfa in the South China Sea. Linfa is now forecast to brush by southeastern Taiwan this weekend.

On June 18 at 11 a.m. EDT (15:00 UTC), Linfa had maximum sustained winds near 40 knots (46 mph) with higher gusts making it a tropical storm. Linfa's center was located 375 miles southwest of Kaohsiung, Taiwan near 17.5 north and 116.4 east. It is currently quasi-stationary, however it is expected to move on a northeasterly direction later today. Meanwhile, another cyclone appears to be developing to Linfa's south.

NASA's Tropical Rainfall Measuring Mission (TRMM) satellite flew over the tropical storm on June 18 at 3:05 a.m. EDT (07:05 UTC) and captured the horizontal pattern of rain intensity within Linfa. In the TRMM image, the storm's center is located near the yellow, green and red areas, which indicate rainfall between 20 and 40 millimeters (.78 to 1.57 inches) per hour. The very tiny red areas are considered moderate rainfall. TRMM is a joint mission between NASA and the Japanese space agency JAXA.

The Atmospheric Infrared Sounder (AIRS) instrument aboard NASA's Aqua satellite captured Linfa's cold clouds in an image from June 18 at 1:35 a.m. EDT (5:35 UTC). The coldest cloud temperatures appear in the false-color image in purple indicating stronger storms. The second coolest cloud temperatures are in blue. The AIRS data creates an accurate 3-D map of atmospheric temperature, water vapor and clouds, all of which are helpful to forecasters.

Over the weekend Linfa is expected to brush the east coast of Taiwan before heading back out to sea in a northeasterly direction.

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



June 17, 2009

03W's thunderstorms and high clouds (in blue and purple) are seen in this Aqua satellite AIRS image.Cyclone 03W's thunderstorms and high clouds (in blue and purple) are seen in this Aqua satellite AIRS image. > Larger image
Credit: NASA JPL, Ed Olsen
Philippine Tropical Depression Expected to Become a Tropical Storm

The northwestern Pacific Ocean is warming up, and forecasters at the U.S. Navy's Joint Typhoon Warning Center that forecasts in that region, are watching Tropical Depression 03W for development into a tropical storm by this weekend.

Forecasters at PAGASA, also known as The Philippine Atmospheric, Geophysical, and Astronomical Services Administration also believe the Tropical Depression 03W will strengthen into a tropical storm. If it does, it will be given the name "Feria."

On Wednesday, June 16 at 11 a.m. EDT (1500 GMT), Tropical Depression 03W had sustained winds of 30 knots with higher gusts. At that time, it was located about 330 miles southwest of Kaohsiung, Taiwan, near 18.2 degrees north latitude and 116.7 degrees east longitude. It was already generating 7-foot high waves. TD 03W's heavy rains are expected to affect northern Luzon, The Philippines, on Saturday, June 20.

The Atmospheric Infrared Sounder (AIRS) instrument on NASA's Aqua satellite captured an infrared image of the Tropical Depression 03W on June 17 at 12:47 a.m. EDT (4:47 UTC).

The infrared image shows the storm's high, cold cloud-tops (in blue and purple) and the warm (in orange) ocean temperatures. The surrounding ocean waters temperatures are 80F (300 degrees Kelvin) or warmer. The storm's lowest temperatures (in purple) are as cold as or colder than 220 degrees Kelvin or minus 63 degrees Fahrenheit (F). The blue areas are around 240 degrees Kelvin, or minus 27F.

According to the Joint Typhoon Warning Center, "The system is expected to continue to track slowly to the west-northwest through 36 hours" before it curves to the northeast. In the meantime, vertical wind shear (winds blowing in different directions at different heights in the atmosphere that weaken a storm) is expected to continue hampering intensification" for another day and a half. After that time, the storm could strengthen.

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