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Hurricane Season 2012: Typhoon Sanvu (Western North Pacific Ocean)
05.29.12
 
This infrared image of Typhoon Sanvu was captured on May 25 when Sanvu was around its peak.› View larger image
This infrared image of Typhoon Sanvu was captured on May 25 at 1559 UTC (11:59 a.m. EDT) when Sanvu was around its peak. Notice the visible eye of the storm around the strong thunderstorms (purple) with high, cold cloud top temperatures. Sanvu ran into much cooler ocean temperatures and wind shear that quickly weakened it over the May 27-28 weekend.
Credit: NASA/JPL, Ed Olsen
This visible image of Typhoon Sanvu was taken from MODIS on May 26, 2012› View larger imageLINK
This visible image of Typhoon Sanvu was taken from the MODIS instrument onboard NASA's Terra satellite on May 26, 2012 at 0130 UTC (May 25 at 9:30 p.m. U.S./EDT). By this time Sanvu had weakened and its eye was no longer visible.
Credit: NASA Goddard MODIS Rapid Response Team
Typhoon Sanvu Had a Bad Weekend

Typhoon Sanvu had a bad weekend. It went from Typhoon status on May 25 to an extra-tropical storm and finally into a remnant low pressure area by May 29, 2012.

NASA's Aqua satellite captured an infrared image of Typhoon Sanvu on May 25 at 1559 UTC (11:59 a.m. EDT) when Sanvu was around its peak. The image clearly showed a visible eye surrounded by strong thunderstorms with high, cold cloud top temperatures. Those cloud-top temperatures were colder than -63 Fahrenheit (-52 Celsius) indicating they were high in the troposphere. Those strong storms were generating rainfall rates of more than 1 inch (25.4 mm) per hour.

A visible image of Typhoon Sanvu was taken from the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument onboard NASA's Terra satellite on May 26, 2012 at 0130 UTC (May 25 at 9:30 p.m. U.S./EDT). By that time Sanvu had weakened as it moved into cooler sea surface temperatures and its eye was no longer visible.

Sanvu ran into much cooler ocean temperatures and wind shear that quickly weakened it over the May 27-28 weekend. On May 27, Tropical Storm Sanvu passed Chichi Jima and entered the open waters of the Pacific. At 5 a.m. EDT on May 27, Sanvu was about 245 miles east of Chichi Jima island, Japan and moving east-northeast at 15 knots (17.2 mph/27.8 kph).

Wind shear was pushing most of the rainfall to the northeast of the center and weakening the storm, as was seen in a satellite image from NASA's Tropical Rainfall Measuring Mission (TRMM) satellite. It was on May 27, that the final warning on Sanvu was issued the Joint Typhoon Warning Center.

Text Credit: Rob Gutro
NASA Goddard Space Flight Center, Greenbelt, Md.












May 25, 2012

image of Sanvu derived from satellite data › Larger image
Infrared imagery from NASA's Atmospheric Infrared Sounder (AIRS) instrument onboard NASA's Aqua satellite was taken on May 25 at 0353 UTC (May 24, 1153 p.m. EDT) shows a large area of high, cold cloud tops around Sanvu's eye. The strongest storms appear in purple, south of the eye, and in a band to the north of the eye and have a cloud top temperature colder than -63F (-52C).
Credit: NASA/JPL, Ed Olsen
satellite image of Sanvu › Larger image
Another instrument on NASA's Aqua satellite captured a stunning view of Typhoon Sanvu that clearly showed an eye. The image was taken on May 25 at 0355 UTC from the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument onboard Aqua. Credit: NASA Goddard's MODIS Rapid Response Team)
Typhoon Sanvu Affecting Iwo To, Then Expected to Fade Over Weekend

Infrared and visible imagery from NASA's Aqua satellite taken on May 25, 2012, showed an impressive Typhoon Sanvu already affecting the islands of Iwo To and Chichi Jima, Japan. The typhoon is expected to run into cooler waters and become extra-tropical over the next several days.

Infrared imagery from May 25 at 0353 UTC (May 24, 1153 p.m. EDT) by NASA's Atmospheric Infrared Sounder (AIRS) instrument that flies onboard NASA's Aqua satellite showed a large area of high, cold cloud tops around Sanvu's eye. The strongest storms appear south of the eye, and in a band to the north of the eye. Those storms have cloud top temperatures colder than -63F (-52C), indicating they are high in the troposphere. Over the last 24 hours, those cloud tops have actually cooled, indicating they were getting higher, and the storms were intensifying. That's because the upper-level atmosphere was cooling.

On May 25, 2012 at 1500 UTC (11 a.m. EDT/U.S.), Typhoon Sanvu had maximum sustained winds near 60 knots (69 mph/111 kph), slightly weaker than it was on May 24. Typhoon-force winds cover a compact area, extending 25 miles (40 km) from the center, while tropical storm-force winds extend as far as 150 miles (241.4 km) from the center, making the storm over 300 miles (~483 km) in diameter.

Sanvu's center was located near 23.9 North and 140.3 East, only 100 nautical miles (115 miles/185 km) southwest of Iwo To, Japan and moving to the north-northeast at 7 knots (8 mph/13 kph). Sanvu continues to churn up rough seas, and the Joint Typhoon Warning Center reported that wave heights in the region are as high as 31 feet (9.4 meters).

Another instrument on NASA's Aqua satellite captured a stunning view of Typhoon Sanvu that clearly showed an eye. The image was taken on May 25 at 0355 UTC from the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument onboard Aqua.

Iwo To and Chichi Jima will continue to experience rough surf, showers, thunderstorms and gusty winds today, as well as on Saturday, May 26. On May 25 at 11 a.m. U.S. Eastern Time, Iwo To was experiencing thunderstorms and winds from the east between 40 to 55 mph (64 to 88.5 kph). Winds are expected to shift to the north as Sanvu continues moving by. Rainfall of up to 2 inches (50 mm) is expected on the island with more on May 26.

Forecasters at the Joint Typhoon Warning Center noted that Sanvu has likely reached its maximum intensity and will hold there before starting to weaken early on May 26 (U.S. Eastern Time). Once Sanvu gets up to 25 degrees North latitude, the ocean surface temperatures are much cooler, and will weaken the storm. A tropical cyclone needs a sea surface temperature of 80F/26.6C to maintain intensity. On May 25, Sanvu is located in an area where sea surface temperatures are around 27 Celsius (80.6F), and temperatures where it is headed are as cold as 23 Celsius (73.4F).

This animation of Typhoon Sanvu was created from 3-D images of TRMM satellite data during the week of May 21, 2012, as the storm moved through the western North Pacific Ocean. This video takes the TRMM data, which shows rainfall intensity within Sanvu, and applies additional processing. While there is no scientific value to this processing, it does result in a new way of looking at the data. (Credit: NASA's Goddard Space Flight Center)

In addition to the cooler ocean temperatures, wind shear is expected to kick up over the next couple of days and will help weaken the storm. By the end of the weekend, Sanvu is expected to transition to an extra-tropical low pressure area in the Northern Pacific Ocean.

Text Credit: Rob Gutro
NASA Goddard Space Flight Center, Greenbelt, Md.



May 24, 2012

NASA's TRMM Satellite Sees Some Heavy Rainfall in Typhoon Sanvu. › View larger image
This TRMM image of rainfall from Typhoon Sanvu was taken on May 24, 2012. Sanvu's heaviest rainfall was occurring in its northeastern quadrant where some intense storms were dropping rainfall at a rate greater than 50mm/hr (~2 inches/hr). TRMM shows that the rainfall wraps around the eastern side of the storm, stretching from north to south, while the western side of the storm is deficient in rainfall. Light to moderate rainfall was falling at a rate between .78 inches and 1.57 inches per hour (20 to 40 mm).
Credit: NASA/TRMM, Hal Pierce
NASA's TRMM Satellite Sees Some Heavy Rainfall in Typhoon Sanvu

Tropical Storm Sanvu strengthened overnight as forecast and is now a Typhoon in the western North Pacific Ocean. NASA's Tropical Rainfall Measuring Mission (TRMM) satellite observed that most of the rainfall is falling in the eastern half of the storm.

The TRMM satellite measured the rainfall from Typhoon Sanvu on May 24, 2012.TRMM's Microwave Imager (TMI) and Precipitation Radar (PR) data shows that Sanvu's heaviest rainfall was occurring in its northeastern quadrant where some intense storms were dropping rainfall at a rate greater than 50mm/hr (~2 inches/hr). TRMM shows that the rainfall wraps around the eastern side of the storm, stretching from north to south, while the western side of the storm is deficient in rainfall.

On May 24 at 1500 UTC (11 a.m. EDT/U.S.), Typhoon Sanvu had maximum sustained winds near 65 knots (75 mph/120.4 kph). It was about 275 nautical miles south-southwest of Iwo To, Japan, near 21.2 North and 138.9 East. Sanvu is causing high waves throughout the region, and waves have been estimated as high as 29 feet (8.8 meters). It is moving to the north at 9 knots (10.3 mph/16.6 kph).

Forecasters at the Joint Typhoon Warning Center now forecast the Sanvu will likely take a track very close to the island of Iwo To, Japan early on May 26. Iwo To was reporting thunderstorms and winds from the east-southeast by mid-day (U.S. EDT) on May 24 (May 25 local time) which are associated with the east-southeasterly flow from the approaching typhoon. As Sanvu continues to approach, thunderstorms from the typhoon will be affecting the island on May 26.

Text Credit: Rob Gutro
NASA Goddard Space Flight Center, Greenbelt, Md.



May 23, 2012

image of Sanvu derived from satellite data › Larger image
On May 23, the TRMM passed over Sanvu again and captured more data. The 3-D image created from TRMM PR data revealed that an eye was almost formed indicating that Sanvu may soon be a typhoon. Several towers in the forming eye wall extend to heights above 16km (~9.94 miles).
Credit: NASA/TRMM, Hal Pierce
image of Sanvu derived from satellite data › Larger image When NASA's TRMM satellite passed over Tropical Storm Sanvu on May 22, 2012 at 1535 UTC data revealed the highest convective thunderstorm towers, reaching to heights above 16km (~9.9 miles), were in a feeder band on the southeastern side of the storm. Credit: NASA/TRMM, Hal Pierce
image of Sanvu derived from satellite data › Larger image
Infrared satellite imagery from NASA's Atmospheric Infrared Sounder (AIRS) instrument on May 23 at 0405 UTC (12:05 a.m. EDT) shows that Sanvu's feeder bands are mostly on the eastern side of the center of circulation and have become more tightly wrapped around the center. Those thunderstorms within the feeder bands have also strengthened. The strongest storms appear in purple and have a cloud top temperature colder than -63F (-52C).
Credit: NASA/JPL, Ed Olsen
NASA Sees Tropical Storm Sanvu Continue to Intensify

Two NASA satellites have provided infrared and rainfall data that has shown Tropical Storm Sanvu continues to intensify as it heads toward Iwo To, Japan. NASA's Tropical Rainfall Measuring Mission (TRMM) satellite has scanned rainfall rates, and NASA's Aqua satellite has provided a look at cloud temperatures which indicates where the strongest thunderstorms and heaviest rainfall is occurring.

The TRMM satellite saw the intensifying storm on May 22, 2012 at 1535 UTC when wind speeds had reached to over 45 knots (~52 mph). Data from TRMM's Microwave Imager (TMI) and Precipitation Radar (PR) instruments show that Sanvu had a very large area of heavy rainfall wrapping around the northeastern side. TRMM's PR also shows that the highest convective storm towers, reaching to heights above 16km (~9.9 miles), were in a feeder band on the southeastern side.

On May 23, the TRMM passed over Sanvu again after it had strengthened further, and captured more data. That data was used to create another 3-D analysis at NASA's Goddard Space Flight Center in Greenbelt, Md. The 3-D image created from TRMM PR data revealed that an eye was almost formed indicating that Sanvu may soon be a typhoon. Several towers in the forming eye wall extend to heights above 16km (~9.94 miles). These towers contain the heaviest rains and act to energize the core of the storm.

On May 23 at 1500 UTC (11 a.m. EDT), Tropical Storm Sanvu has maximum sustained winds near 60 knots (69 mph/111 kph). It was located about 450 nautical miles south-southwest of Iwo To, Japan and moving toward the island in a northwesterly direction at 10 knots (11.5 mph/18.5 kph). Sanvu's center is near 17.8 North and 139.2 East.

Infrared satellite imagery from NASA's Atmospheric Infrared Sounder (AIRS) instrument onboard NASA's Aqua satellite showed that Sanvu's feeder bands were mostly on the eastern side of the center of circulation and have become more tightly wrapped around the center. Those thunderstorms within the feeder bands have also strengthened. The strongest storms have a cloud top temperature colder than -63F (-52C) indicating they are high in the troposphere and powerful.

Sanvu is predicted to intensify further and become the first western Pacific typhoon of 2012. One factor that is helping Sanvu continue to intensify is the warm sea surface temperatures at 86 degrees Fahrenheit (30 Celsius).

The current forecast track takes it just east of Iwo To and Chichi Jima, which may experience typhoon conditions on May 25 and 26, respectively.

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



















May 22, 2012

This infrared image of Tropical Storm Sanvu was captured from the AIRS instrument on NASA's Aqua satellite on May 22, and shows a large area of very strong thunderstorms near the center of circulation.› View larger image
This infrared image of Tropical Storm Sanvu was captured from the AIRS instrument on NASA's Aqua satellite on May 22, and shows a large area of very strong thunderstorms near the center of circulation. The purple color indicates the coldest cloud top temperatures, and strongest thunderstorms with the heaviest rainfall.
Credit: NASA JPL, Ed Olsen
NASA Satellite Sees Tropical Storm Sanvu Pass Guam, Strengthen

Tropical Depression 03W in the western North Pacific did exactly what forecasters expected over the last twenty-four hours: it became a tropical storm named Sanvu and passed west of Guam on a northwesterly track.

On May 22 at 0900 UTC (5 a.m. EDT), Tropical Storm Sanvu was more than 100 miles west-northwest of Andersen Air Force Base, Guam, and still over 600 nautical miles south of Iwo To, Japan and headed in that direction. Sanvu's center was located near 15.2 North and 141.9. East. It was still churning up rough surf around Guam. Sanvu has maximum sustained winds near 45 knots (52 mph/83 kph) with higher gusts. Sanvu is a compact tropical storm, with tropical-storm-force winds extending out 90 miles from the center, making it about 180 miles in diameter.

An infrared image of Tropical Storm Sanvu was captured from the Atmospheric Infrared Sounder (AIRS) instrument onboard NASA's Aqua satellite on May 22, and shows a large area of very strong thunderstorms near the center of circulation. Forecasters at the Joint Typhoon Warning Center noted the AIRS imagery "shows the system has further consolidated and convection has resurged, especially along the northeast flank."

Forecasters expect Sanvu to keep intensifying as it moves closer to Iwo To because of warm sea surface temperatures and light wind shear. Thereafter it is expected to curve to the northeast and transition to an extra-tropical storm.

Text Credit: Rob Gutro
NASA Goddard Space Flight Center, Greenbelt, Md.



May 21, 2012

TRMM data revealed a hot tower over 15 kilometers (9.3 miles) high in Tropical Depression 03W.› View larger image
When NASA's TRMM satellite passed over TD03W on May 21, 2012 at 0642 UTC (2:42 a.m. EDT), data revealed a hot tower over 15 kilometers (9.3 miles) high. TRMM also measured rainfall within the tropical depression, and found that isolated areas of heavy rain (falling at a rate of 2 inches/50 mm per hour (appearing in red)) were seen in the western quadrant of the storm. Light to moderate rainfall was falling at a rate between .78 inches and 1.57 inches per hour (20 to 40 mm).
Credit: NASA/TRMM, Hal Pierce
NASA Sees Tropical Depression 03W's "Hot Tower" on Approach to Guam

NASA's Tropical Rainfall Measuring Mission satellite has caught two tropical cyclones with "hot towers" this week, and that's a hallmark that they'll intensify. Tropical Depression 03W is approaching Guam and is expected to strengthen.

"Hot Tower" rain clouds within a tropical cyclone indicate that the storm is going to intensify, and that's what NASA's TRMM satellite spotted in newborn Tropical Depression 2E in the eastern Pacific Ocean and now in Tropical Depression 03W (TD03W) in the western North Pacific Ocean.

A "hot tower" as a rain cloud that reaches at least to the top of the troposphere, the lowest layer of the atmosphere. These towers are called "hot" because they rise to such altitude due to the large amount of latent heat. Water vapor releases this latent heat as it condenses into liquid.

When NASA's TRMM satellite passed over TD03W on May 21, 2012 at 0642 UTC (2:42 a.m. EDT), data revealed a hot tower over 15 kilometers (9.3 miles) high. That's an indication that the storm is going to intensify, and that's one factor that forecasters at the Joint Typhoon Warning Center are using in their forecast, which calls for TD03W to become a tropical storm.

TRMM also measured rainfall within the tropical depression, and found that isolated areas of heavy rain (falling at a rate of 2 inches/50 mm per hour) were seen in the western quadrant of the storm. Light-to-moderate rainfall was falling throughout the rest of the storm.

Tropical Depression 03W is close to Guam, just 160 nautical miles south-southeast of Andersen Air Force Base, Guam, near 10.8 North and 145.9 East. It is bringing rain and gusty winds and will continue to do so as it tracks to the west of Guam over the next couple of days and swings to the northeast. Maximum sustained winds are near 25 knots with higher gusts. TD03W is moving to the west, but is expected to turn to the northeast in a couple of days.

Text Credit: Rob Gutro
NASA Goddard Space Flight Center, Greenbelt, Md.