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Hurricane Season 2009: Typhoon Mirinae (Western Pacific)
11.03.09
 
November 3, 2009

TRMM Precipitation Analysis showed Mirinae's rainfall from Oct. 26-Nov. 2 from the Philippines to landfall in Vietnam. > View larger image
TRMM Precipitation Analysis showed Mirinae's rainfall from Oct. 26-Nov. 2 from the Philippines to landfall in Vietnam. Tropical storm, typhoon and tropical depression symbols show locations, date and time. Rainfall totaled over 200 mm (~7.8 inches) in an area southeast of Manila in the Philippines. Parts of Vietnam received over 275 mm (~10.8 inches).
Credit: NASA/SSAI, Hal Pierce
Typhoon Ketsana took a similar path to Mirinae when it caused disasters in the Philippines and Vietnam in late September 2009. > View larger image
Typhoon Ketsana took a similar path to Mirinae when it caused disasters in the Philippines and Vietnam in late September 2009. The graphic on the right shows the track of tropical storm Ketsana in black and typhoon Mirinae's path in white. Manila in the Philippines and Da Nang's locations in Vietnam are shown by red cursors.
Credit: NASA/SSAI, Hal Pierce
NASA's TRMM Satellite Provides a Rainfall Map of Mirinae's Flooding Rains

Typhoon Mirinae drenched the Philippines and Vietnam over the last two weeks. Typhoon Mirinae dropped heavy rain over the central Philippines after hitting as a category two typhoon with wind speeds of 85 knots (~98 mph). Mirinae weakened to a tropical storm as it moved into the South China Sea but briefly increased to typhoon strength just before hitting Vietnam on Monday, November 2 in the southern coastal province of Phu Yen.

The Tropical Rainfall Measuring Mission (TRMM) satellite is managed by NASA and the Japanese Space Agency, JAXA. From its vantage point in space, TRMM flew over Typhoon Mirinae during its lifetime and catalogued its rainfall.

TRMM-based, near-real time Multi-satellite Precipitation Analysis (TMPA) at the NASA Goddard Space Flight Center, Greenbelt, Md. was used to monitor rainfall with Mirinae. Rainfall totals were calculated for the period from October 26 to November 2, 2009. Tropical storm, typhoon and tropical depression symbols were overlaid to show the locations of Mirinae from when it came ashore in the eastern Philippines until being downgraded to a tropical depression over Vietnam.

The TRMM rainfall analysis indicated that Mirinae dropped heavy rainfall with totals over 200 mm (~7.8 inches) in an area southeast of Manila in the Philippines. Typhoon Mirinae dropped heavy rainfall over a much larger area of Vietnam with a small area having rainfall totals over 275 mm (~10.8 inches). As with typhoon Ketsana in late September, Mirinae pulled moist air from the South China Sea and forced it up over terrain causing the heaviest rainfall to occur north of the typhoon.

Typhoon Ketsana took a similar path to Mirinae when it caused disasters in the Philippines and Vietnam in late September 2009. Tropical storm Ketsana took a more northern track, also making a final landfall in Vietnam.

Heavy rain amounts (from satellites) and flood potential calculations (from a hydrological model) are updated every three hours globally with the results shown on the "Global Flood and Landslide Monitoring" TRMM web site pages (http://trmm.gsfc.nasa.gov).

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






Mirinae on Nov. 1st at 10:29 UTC in the South China Sea, headed for a landfall in Vietnam. > View larger image
NASA's QuikScat captured Mirinae on Nov. 1st at 10:29 UTC in the South China Sea, headed for a landfall in Vietnam. The purple area in the center revealed the strongest winds. At this time, maximum sustained winds were near 45 mph. Wind direction is indicated by small barbs. White barbs point to areas of heavy rain.
Credit: NASA JPL, Peter Falcon
QuikScat Catches Mirinae's Tropical Storm Force Winds Before Landfall

One of the satellites forecasters use to verify surface wind speed is NASA's Quick scatterometer or QuikScat. QuikScat uses microwave technology that can actually see through clouds and analyze spinning winds of tropical cyclone on Earth's surface and measured Mirinae's winds before it made landfall.

NASA's Quick Scatterometer satellite (QuikScat) passed over Tropical Storm Mirinae on November 1 at 10:29 UTC (5:29 a.m. ET) and confirmed tropical storm force winds. QuikScat uses microwaves to peer into a storm's clouds and determine the speed of the rotating winds at the surface. At that time, maximum sustained winds were 57 mph.

On November 2 at 10 a.m. EDT or 7 p.m. local (Asia/Ho_Chi_Minh) time in Vietnam, Mirinae already crossed the South China Seas and made landfall in Vietnam. It made landfall around 1 a.m. EDT on November 2. It has since dissipated.

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



November 2, 2009

Tropical Storm Mirinae November 1 while it was tracking toward Vietnam for a final landfall. > View larger image
NASA's Aqua satellite AIRS instrument captured Tropical Storm Mirinae November 1 while it was tracking toward Vietnam for a final landfall. The infrared imagery still showed some high thunderstorms (purple), despite a weakening storm. Look closely to see the eye.
Credit: NASA JPL, Ed Olsen
Mirinae Floods Philippines, Makes Landfall in Vietnam With Strong Thunderstorms

Mirinae (Santi) caused 12 hours of flooding rains in the Philippines when it crossed the northern Luzon region over the weekend. On October 31 at 5 a.m. local (Asia/Manila) time (October 30 at 2100 UTC) Typhoon Mirinae weakened dramatically after it moved inland over central Luzon, the Philippines.

By October 31 at 5 p.m. Local time, Mirinae had already reemerged into the South China Sea as a tropical storm and was headed for Vietnam, but it left behind floods, destruction and death. Mirinae made landfall in Vietnam early this morning, Eastern Time.

NASA's Aqua satellite captured an image of Mirinae as it tracked through the South China Sea yesterday, November 1 and had maximum sustained winds near 57 mph. The storm still maintained good formation, and Aqua's Atmospheric Infrared Sounder (AIRS) instrument still showed some high thunderstorms implying moderate to heavy rainfall, within. The infrared imagery also showed an eye in the storm, where the clouds were lower and warmer. The surrounding clouds had temperatures colder than -63F than those in the "eye."

By November 2 at 10 a.m. EDT or 7 p.m. local (Asia/Ho_Chi_Minh) time in Vietnam, Tropical Storm Mirinae had already crossed the South China Seas and made landfall in Vietnam. It made landfall around 1 a.m. EDT this morning, November 2. By 10 a.m. EDT today, it was located 155 miles northeast of Ho Chi Minh, Vietnam, near 12.7 North and 108.5 East. Mirinae had maximum sustained winds near 52 mph, and was moving west near 14 mph. Mirinae is now dissipating over Vietnam and western Cambodia. The storm's remnants could move into the Gulf of Thailand, but Mirinae isn't expected to regenerate.

When Mirinae, or Santi, as it was called in the Philippines, tracked over northern Luzon, it dropped copious amounts of rainfall causing serious flooding, power outages and landslides taking at least 10 lives. More than 10,000 people in 54 villages were reported affected.

According to GMA News.TV several areas in Metro Manila and Southern Luzon are still flooded today. There was a flash flood in Laguna. Floods and damages were reported in Cavite and a storm surge from Mirinae destroyed homes in Barangay.

Navotas City's Daanghari village, Pasig City's Santolan and Kalawaan villages, and Taguig City's Bagumbayan, Lower Bicutan and Ibayo-Tipas villages all reported flooding. In Laguna, the Santa Cruz River flowed over its banks, and flooded 85 percent of Santa Cruz town. Floodwaters were also reported in Rizal and San Lorenzo villages in Santa Elena town.

When Mirinae left Luzon and entered the South China Sea late on October 31, its maximum sustained winds were down to 63 mph (55 knots) and it was a tropical storm. Early this morning it made its final landfall in Vietnam.

Today brings a day of clean up in Luzon, but an awareness of yet another tropical threat. 320 miles northeast of Manila in the Philippine Sea, another tropical depression has formed and it may track over the northern Philippines in the next several days.

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



October 30, 2009

The Philippines (left), part of which are already under a part of Mirinae's clouds. > View larger image
The MODIS instrument on NASA's Aqua satellite captured an image of Typhoon Mirinae on October 30 at 1 p.m. local Asia/Manila Time approaching the Philippines (left), part of which are already under a part of Mirinae's clouds.
Credit: NASA MODIS Rapid Response
Cold areas (yellow-green) indicate precipitation or ice in the cloud tops. > View larger image
This microwave image of Mirinae on October 30 shows its center just east of making a landfall. Cold areas (yellow-green) indicate precipitation or ice in the cloud tops. The purple area (around the eye) has the coldest cloud temperatures.
Credit: NASA JPL, Ed Olsen
Mirinae's high clouds (purple and blue) on October 30 are colder than -63F. > View larger image
This infrared image from AIRS shows the extent of Mirinae's high clouds (purple and blue) on October 30 are colder than -63F.
Credit: NASA JPL, Ed Olsen
The track of Tropical Storm Ketsana in black and the predicted path of Typhoon Mirinae in white. > View larger image
When Tropical Storm Ketsana moved over the Philippines in late September it produced very heavy rain causing deadly mudslides and flooding in Manila. This graphic shows the track of Tropical Storm Ketsana in black and the predicted path of Typhoon Mirinae in white.
Credit: NASA/SSAI, Hal Pierce
Typhoon Mirinae Already Raining on the Philippines

Infrared imagery from NASA's Aqua satellite revealed that Typhoon Mirinae's cold thunderstorm clouds were already over sections of the central and northern Philippines on October 30 at 4:53 p.m. (Asia/Manila) local time.

Microwave satellite imagery from NASA's Aqua satellite showed that Mirinae's center was close to making a landfall as the storm continued its approach from the east. The Atmospheric Infrared Sounder (AIRS) instrument provided infrared data on Mirinae's cloud top temperatures, and showed some strong convection and strong thunderstorms with moderate to heavy rainfall over eastern sections of the northern Philippines. The microwave image was created combining AIRS and Advanced Microwave Sounding Unit (AMSU) data. AMSU is another instrument that flies on NASA's Aqua satellite.

The microwave image revealed cold areas in the storm that indicate ice in cloudtops, and heavy precipitation. Around the eye are the coldest cloud temperatures, as cold as -63F. Microwave data suggests cloud heights to the 200 millibar level, near the tropopause.

Mirinae is also known as "Santi" in the Philippines. Warnings are in effect there are Mirinae (or Santi) is already raining in areas on Friday. Public storm warning signal 3 is in effect in the following districts of Luzon: Quezon, Polillo island, Bulacan, Bataan, Rizal, Cavite, Laguna, Batangas, Oriental Mindoro, Lubang Island, Marinduque, Camarines Norte, Camarines Sur, Catanduanes, Metro Manila; Public storm warning signal 2 is in effect in the following districts of Luzon: Aurora, Quirino, Nueva Ecija, Tarlac, Pampanga, Zambales, Occidental Mindoro, Albay, Burias Island; and Public storm warning signal 1 is in effect in the following districts of Luzon: Isabela, Ifugao, Nueva Vizcaya, Benguet, La Union, Pangasinan, Sorsogon, Masbate, Romblon, Calamian Group. In Visayas, the signal is raised in Northern Samar and Northern Panay.

On October 30 at 5 p.m. local (Asia/Manila) time, or 5 a.m. EDT, Typhoon Mirinae still had maximum sustained winds near 85 knots (97 mph or 157 kph). Typhoon-force winds extend for 30 to 40 miles from the center, while tropical storm-force winds extend as far as 140 miles from the center. Mirinae was centered 205 miles east of Manila, near 14.9 North and 124.6 East.

The Tropical Rainfall Measuring Mission (TRMM) satellite, managed by NASA and JAXA, flew over Mirinae on October 29 and analyzed the rainfall within the storm. The rainfall analysis from the TRMM Microwave Imager and Precipitation Radar instruments showed heavy rainfall of over 30 millimeters (1.18 inches) per hour falling near the typhoon's center. Typhoon Mirinae has been predicted by the Joint Typhoon Warning Center to pass over the Philippines south of where tropical storm Ketsana traveled in late September. Mirinae is currently predicted to pass within about 44 nautical miles (~81.5 km) to the north of Manila on 31 October 2009. When tropical storm Ketsana moved over the Philippines in late September it produced very heavy rain causing deadly mudslides and flooding in Manila.

Mirinae has weakened as it interacts with the land of the Philippines. The storm will pass over the Philippines and re-emerge into the South China Sea over the weekend.

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



















October 29, 2009

TRMM image of Mirinae> View larger image
NASA and JAXA's TRMM satellite captured the rainfall in Typhoon Mirinae on October 29 at 1018 UTC. Mirinae had moderate rainfall (yellow-green) around its center. Rainfall was between .78 to 1.57 inches per hour. Credit: NASA /SSAI, Hal Pierce
Typhoon Mirinae is Already Scaring Philippine Residents Before Halloween

Another typhoon in the northern Philippines really is something to be scared about, and Mirinae is expected to make landfall there in the mid-morning hours on Halloween, October 31. Mirinae will be the fourth major storm to hit the Philippines in one month bringing more rain to an already flood-weary region.

NASA's Tropical Rainfall Measuring Mission (TRMM) satellite is already hard at work analyzing rainfall, to provide meteorologists with an idea of what can be expected when the storm hits.

NASA and the Japanese Space Agency's TRMM satellite flew over Typhoon Mirinae on October 29 at 1018 UTC and measured its rainfall from space. Mirinae had moderate rainfall between .78 to 1.57 inches per hour around its center. TRMM images are made at NASA's Goddard Space Flight Center in Greenbelt, Md. and take some ingenuity to create. A typical TRMM rainfall image combines the infrared and visible channels overlaid with a precipitation analysis from the TRMM Microwave Imager and PR instruments.

The government of the Philippines isn't waiting for the storm to arrive. It is already sending evacuating people and sending in relief supplies.

On October 29 at 11 a.m. EDT (11 p.m. Asia/Manila Time), Mirinae had maximum sustained winds near 90 knots (104 mph or 167 km/hour). Mirinae's center was about 480 nautical miles east of Manila, near 15.6 North and 128.7 East. It was still moving west near 12 knots (14 mph) and kicking up dangerous waves as high as 31 feet high.

The environment that Typhoon Mirinie is in is enabling the storm to maintain intensity. Mirinae is in an area of light-to-moderate vertical wind shear. Strong wind shear (winds blowing at different levels of the atmosphere) can tear a storm apart, but that's not the case in the Philippine Sea where Mirinae is currently located. In addition, the sea surface temperatures remain warm there, in excess of 28 degrees Celsius (82 Fahrenheit). In order for a typhoon or hurricane to maintain intensity, it needs sea surface temperatures as warm as 80F.

Current forecasts expect Mirinae's center to make landfall sometime around 8 a.m. Asia/Manila time on October 31, and after 12 hours, the storm is expected to move into the South China Sea.

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



October 28, 2009

Mirinae now has the developed signature shape of a mature tropical cyclone. > View larger image
NASA's Aqua satellite captured cold thunderstorm cloud tops of Mirinae in this infrared image October 28 at 12:35 a.m. local Asia/Manila Time (October 27 at 12:35 p.m. EDT). The system now has the developed signature shape of a mature tropical cyclone
Credit: NASA/JPL, Ed Olsen
The cold areas in this image (yellow-green) indicates where there is precipitation or ice in the cloud tops. > View larger image
Microwave images are created when data from NASA's Aqua satellite AIRS and AMSU instruments are combined. The cold areas in this image (yellow-green) indicates where there is precipitation or ice in the cloud tops. The microwave image suggests cold, high thunderstorms.
Credit: NASA/JPL, Ed Olsen
Mirinae Intensifying While Moving Away from the Northern Marianas

Typhoon Mirinae is moving west and away from the Northern Marianas Islands on a track to a landfall in the Philippines by the weekend. As Mirinae has moved west, NASA's infrared and microwave satellite imagery have seen high, strong thunderstorm development, and a developing eye.

Typhoon Mirinae's maximum sustained winds are now up to 98 mph (157 km/hr), and its center is approximately 930 nautical miles (that's 1,070 miles or 1,722 kilometers) east of Manila, Philippines. The coordinates of its center are 16.2 North latitude and 136.9 East longitude. Mirinae is moving west at 17 mph.

Tropical storm-force winds extend out to 100 miles from Mirinae's center, while typhoon/hurricane-force winds extend 20 miles out from its center. Mirinae is stirring up waves up to 22 feet high.

Mirinae is intensifying in part because of "strong radial outflow and warm sea surface temperatures," according to forecasters at the U.S. Navy's Joint Typhoon Warning Center (JTWC). JTWC is the organization that forecasts storms in the Western Pacific Ocean. Radial outflow is important in a tropical cyclone development because it spreads ice particles outward from the center of the storm, spreading clouds and precipitation. Basically it helps the storm grow larger.

The Atmospheric Infrared Sounder (AIRS) instrument on NASA's Aqua satellite captured a microwave and infrared image of Mirinae on October 28 at 12:35 a.m. local Asia/Manila Time.

The infrared imagery revealed that the cloud tops of Mirinae are close to the top of the troposphere. That means they are strong thunderstorms, where temperatures are colder than -63 Fahrenheit.

AIRS data is also coupled with data from the Advanced Microwave Sounding Unit (AMSU) that flies with AIRS on Aqua to create microwave images of storms. The AMSU image uses the radiances of the 89 GHz channel, and the cold areas in those images indicate where there is precipitation or ice in the cloud tops.

Mirinae has intensified steadily and will continue to do so until landfall in the Philippines on Saturday. Landfall in Luzon between the cities of Soliven and San Jose is still expected to occur around 0600 UTC (2 a.m. EDT, 2 p.m. Asia/Manila local time) on Halloween.

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



October 27, 2009

Microwave Satellite Imagery Shows an Eye Developing in Mirinae

AIRS image of Mirinae > View larger image
This NASA AIRS microwave image of Mirinae from October 27 shows the development of an eye (purple area resembling a half moon). Cold areas (yellow-green) indicate precipitation or ice in the cloud tops. The purple area has the coldest cloud temperatures (as cold as -63F) and suggest cloud tops are near the tropopause.
Credit: NASA/JPL, Ed Olsen
Microwave satellite imagery has revealed that Tropical Storm Mirinae is strengthening enough to develop an eye, and that's what it's doing. Mirinae was formerly Tropical Depression 23W, but became a tropical storm and received its name.

Tropical Storm Mirinae had maximum sustained winds near 52 mph on Tuesday, October 27 at 1200 UTC (8 a.m. EDT). It was located about 205 nautical miles northwest of Guam, so all of the watches and warnings for Guam have been discontinued. Its center is near 15.6 North latitude and 142.2 East longitude. Mirinae was moving west-northwest near 19 mph.

The U.S. Navy's Joint Typhoon Warning Center (JWTC) is the organization that forecasts tropical cyclones in the Western Pacific Ocean. Today's JWTC discussion noted that microwave satellite imagery has shown that the storm is developing an eye, and that's "typical of systems 45 Knots (52 mph) or greater."

NASA's Aqua satellite flew over Tropical Storm Mirinae on October 27 at 0423 UTC. (12:23 a.m. EDT or 12:23 p.m. local Asia/Manila Time). Both infrared and microwave images were created from the Atmospheric Infrared Sounder (AIRS) instrument, and both showed some high, powerful thunderstorms and a developing eye, two signs that the storm was intensifying. A microwave image was created combining AIRS and Advanced Microwave Sounding Unit (AMSU) data. AMSU is another instrument that flies on NASA's Aqua satellite.

AIRS image of Mirinae> View larger image
NASA's Aqua satellite AIRS instrument captured the western half of Tropical Storm Mirinae's cold thunderstorm cloud tops on October 27 at 0423 UTC. Mirinae appears as a round area of clouds (blue) on the right of the image. Credit: NASA JPL, Ed Olsen
The microwave image revealed cold areas in the storm that indicate ice in cloud tops, and heavy precipitation. Because winds are strongest around the eye, that's where you would also likely find the most powerful thunderstorms and rotation, so it makes sense that around the developing eye are the coldest cloud temperatures, as cold as -63F. Microwave data suggests cloud heights to the 200 millibar level, near the tropopause.

Tropical Storm Mirinae continues to move west-northwest, away from the Northern Marianas and toward the Philippines. The storm is forecast to strengthen on its westward track, so residents in the Philippines need to prepare for its arrival toward the end of the week.

The Philippines Atmospheric, Geophysical and Astronomical Services Administration, PAGASA noted on their Web site, "as of today, Tuesday, 27-Oct-2009 23:30:31 PHT no tropical cyclone existing within the Philippine Area of Responsibility (PAR)." That will likely change in the next couple of days.

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



October 26, 2009

NASA's Aqua satellite captured an infrared image of Lupit's and 23W's (bottom right) cold clouds on October 26. > View larger image
NASA's Aqua satellite captured an infrared image of Lupit's and 23W's (bottom right) cold clouds on October 26. Lupit's (top, center) center is seen by the green circle, and the precipitation (blue and purple) is off to the northeast. Meanwhile, 23W is getting organized.
Credit: NASA/JPL, Ed Olsen
NASA's CloudSat satellite captured some high, strong thunderstorm cloud tops almost 9 miles high in 23W. > View larger image
NASA's CloudSat satellite captured a side view of 23W's clouds on Oct. 26 and revealed some high, strong thunderstorm cloud tops almost 9 miles high. The blue area along the top of the clouds indicates cloud ice, while the wavy blue lines on the bottom center of the image indicate intense rainfall (more than 1.18 inches/hour).
Credit: NASA/JPL/Colorado State Univ/NRL
A 2-for-1 for NASA's Aqua Satellite: Lupit and 23W in Western Pacific

It seems like a common occurrence this season that there are two tropical cyclones spinning in the Western Pacific Ocean and this week, Lupit and newly formed 23W are proof. NASA's Aqua satellite flew over the Western Pacific early today and captured both storms in one satellite image.

Tropical Storm Lupit is becoming extra-tropical and is expected to track parallel to Japan while remaining at sea, east of the island. Meanwhile, Tropical Storm 23W is approaching Saipan and Andersen Air Force Base and is moving west.

The U.S. Navy's Joint Typhoon Warning Center (JTWC) forecasts tropical cyclones in the Western Pacific Ocean. The JWTC issued their final warning for Extra-tropical Storm Lupit today, October 26 at 0300 UTC (12 a.m. local time Tokyo). At that time, Lupit had maximum sustained winds near 52 mph and was stirring up rough surf and high waves along eastern Japan's coastline.

Extra-tropical storm Lupit was located approximately 580 nautical miles southwest of Tokyo, Japan, near 28.4 North and 134.8 East. It was moving northeast at 21 mph, and is expected to continue moving in that direction staying in open ocean. Lupit was completing transition to an extra-tropical storm and is also being adversely affected by wind shear (winds blowing at the storm in different levels of that atmosphere, that tear the storm apart).

NASA's Aqua satellite flew over both Lupit and TD23W on October 26 at 3:41 UTC (October 25 at 11:41 p.m. EDT). The Atmospheric Infrared Sounder (AIRS) instrument on Aqua captured both a visible and infrared image of the storms. The infrared satellite image confirmed that all of Lupit's deep convection (developing strong thunderstorms) has dissipated, and the most intense precipitation has shifted all to the northeast of the center of circulation, further exposing the center to wind shear. Meanwhile, the image also showed that 23W appeared to be getting well-organized.

Tropical Storm 23W had maximum sustained winds near 40 mph at 11 a.m. EDT on October 26. The storm's center was about 200 nautical miles east of Guam, near 13.4 North and 147.7 East. It was moving west-northwest near 17 mph.

NASA's CloudSat satellite also flew over 23W earlier this morning. CloudSat captured a side view of 23W's clouds on Oct. 26 between 03:43 – 03:46 UTC. CloudSat revealed sustained winds of 27 mph and a minimum central pressure of 1002 millibars when it was centered near 122 North and 151.3 East. Sustained winds have since increased to 40 mph. CloudSat also showed some high, strong thunderstorm cloud tops over 14 kilometers (almost 9 miles) high.

The forecast track from the JTWC takes Tropical Storm 23W between Andersen Air Force Base (island) and the island of Saipan, located north of Andersen. The storm is then forecast to intensify and move west toward the Philippines.

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