Hurricanes – Page 24 – Hurricane And Typhoon Updates

Vongfong – Northwestern Pacific Ocean

May 17, 2020 – NASA Finds Vongfong a Depression, Last Advisory Issued

NASA-NOAA’s Suomi NPP satellite provided a look at the cloud top temperatures of Vongfong, once a typhoon, now weakened to a tropical depression and expected to dissipate by May 17.

Suomi NPP image of Vongfong — On May 17, NASA-NOAA’s Suomi NPP satellite provided an infrared image of the storm that showed strongest storms were off shore from Luzon, located northeast and northwest of Luzon, where cloud top temperatures were as cold as minus 70 degrees Fahrenheit (red color). Those storms were generating heavy rain. Credit: NASA/NOAA/NRL

At 5 a.m. EDT (0900 UTC) on Saturday, May 16, the Joint Typhoon Warning Center or JTWC issued the final advisory on Tropical Depression Vongfong. At that time, Tropical Depression Vongfong (Philippines designation Ambo) was located near latitude 19.3 degrees north and longitude 120.5 degrees east, about 101 miles north of Vigan, Philippines. Vongfong was moving northeast. Maximum sustained winds dropped to 25 knots (28.7 mph)

The Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard NASA-NOAA’s Suomi NPP satellite provided an infrared image that showed the strongest storms associated with the depression were located offshore, northeast and northwest of Luzon. In those strongest storms, cloud top temperatures were as cold as minus 70 degrees Fahrenheit. Those storms were generating heavy rain.

On May 16, Philippines warnings were still in effect. They included Tropical cyclone wind signal number 2 for Luzon: Ilocos Norte. In addition, Tropical cyclone wind signal number 1 was in effect for these areas in Luzon: Apayao, Abra, Ilocos Sur, La Union, Batanes, Babuyan Islands, and the northwestern portion of Cagayan.

Vongfong’s center had emerged over water west of Luzon and was dissipating.

By Rob Gutro
NASA’s Goddard Space Flight Center

May 16, 2020 – NASA’s IMERG Measures Typhoon Vongfong’s Rainfall

Surface rainfall accumulations (mm) estimated from the NASA IMERG satellite precipitation product from 10 to 17 May 2020 in association with the passage of Typhoon Vongfong. Image from NASA GSFC using IMERG data archived at https://giovanni.gsfc.nasa.gov/giovanni/. This image was produced with the Giovanni online data system, developed and maintained by the NASA GES DISC.

The first typhoon of the season, Vongfong, struck the central Philippines this past week (where it is known as Ambo) as a strong category 2 storm, bringing strong winds and locally heavy rainfall. NASA’s IMERG calculated locally heavy rainfall on the order of 200 mm (~8 inches) or more to the northern half of Samar where it made landfall as well as to southern, far eastern and isolated parts of central Luzon. For the full story: https://gpm.nasa.gov/articles/typhoon-vongfong-hits-philippines

By Steve Lang
NASA Goddard Space Flight Center

May 15, 2020 – Look Back: Vongfong Makes Landfall in the Philippines

The first tropical storm in the Western Pacific Ocean in 2020 did not form until May 12. By May 14, it was making landfall in the Philippines with fierce winds and heavy rainfall. Civil authorities worked to evacuate tens to hundreds of thousands of people from coastal and mountainous areas prone to flooding and landslides. For the entire story: https://earthobservatory.nasa.gov/images/146719/vongfong-makes-landfall-in-the-philippines/?src=eoa-iotd

By NASA Earth Observatory–image by Joshua Stevens, using VIIRS data from NASA EOSDIS/LANCE and GIBS/Worldview and the Suomi National Polar-orbiting Partnership. Story by Michael Carlowicz.

Arthur (was 90L) – Atlantic Ocean

May 17, 2020 – NASA Sees Development of Atlantic’s First Tropical Storm

Tropical Storm Arthur formed off the east coast of Florida from a low-pressure system (90L) that developed days before in the Straits of Florida. NASA-NOAA’s Suomi NPP satellite provided forecasters with an image of the new storm.

Suomi NPP image of Arthur — On May 16, NASA-NOAA’s Suomi NPP satellite provided forecasters with a visible image of Tropical Depression Arthur off the east coast of Florida. Arthur strengthened into a tropical storm soon after Suomi NPP passed overhead. Credit: NASA Worldview, Earth Observing System Data and Information System (EOSDIS)

On Saturday, forecasters at the National Hurricane Center were closely watching System 90L, an area of low pressure that was located just offshore of the southeast coast of Florida. It continued to produce shower activity and gusty winds from portions of southeast and east-central Florida eastward across the northwestern Bahamas and the adjacent Atlantic waters.

Overnight and early on May 17, that low-pressure system became better defined and organized and it became a tropical storm over the Atlantic waters east of Florida.

Visible imagery from NASA satellites help forecasters understand if a storm is organizing or weakening. The Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard Suomi NPP provided a visible image of Arthur late on May 16 when it had been classified as Tropical Depression 1. The shape of a tropical cyclone provides forecasters with an idea of its organization and strength, and NASA-NOAA’s Suomi NPP satellite provided a visible image of Arthur and it appeared more circular in nature.

At 5 p.m. EDT (2100 UTC) on May 16, the center of Tropical Depression 1 was located near latitude 28.4 north, longitude 78.6 west, about 505 miles or 810 kilometers south-southwest of Cape Hatteras, North Carolina. By 11 p.m. EDT, Tropical Depression 1 strengthened into a tropical storm and was renamed Arthur.

On May 17, a Tropical Storm Warning was in effect from Surf City to Duck, NC and for the Pamlico and Albemarle Sounds.

NOAA’s National Hurricane Center said, at 8 a.m. EDT (1200 UTC) on May 17), the center of Tropical Storm Arthur was located near latitude 30.3 north, longitude 77.4 west. Arthur is moving toward the north-northeast near 9 mph (15 kph). Maximum sustained winds are near 40 mph (65 kph) with higher gusts. Tropical-storm-force winds extend outward up to 80 miles (130 km) from the center. The estimated minimum central pressure is 1002 millibars.

Some strengthening is forecast during the next 48 hours. Arthur is likely to lose its tropical characteristics on Tuesday.

A turn toward the northeast with an increase in forward speed is expected during the next 24 to 48 hours. On the forecast track, Arthur will remain well offshore the east coast of Florida, Georgia, and South Carolina today, and then move near or just east of the coast of North Carolina on Monday.

Tropical cyclones/hurricanes are the most powerful weather events on Earth. NASA’s expertise in space and scientific exploration contributes to essential services provided to the American people by other federal agencies, such as hurricane weather forecasting.

For updated forecasts, visit: www.nhc.noaa.gov

By Rob Gutro
NASA’s Goddard Space Flight Center

Vongfong – Northwestern Pacific Ocean

May 15, 2020 – NASA-NOAA Satellite Shows a Weaker Tropical Cyclone Vongfong Over the Philippines

After Tropical Cyclone Vongfong made landfall in the Philippines early on May 14 and began tracking through the country, imagery from NASA-NOAA’s Suomi NPP satellite showed the storm was weakening.

Suomi NPP infrared image of Vongfong — On May 14 at 1:34 p.m. EDT (1734 UTC), NASA-NOAA’s Suomi NPP infrared satellite imagery showed the eye has now closed and convection has diminished within the eastern semicircle of the system, evident in the warming cloud tops. The diminished convection could also be seen in imagery as compared to yesterday, where convection surrounded the circulation. The darker red indicates colder cloud tops and stronger storms. Credit: NASA/NOAA/UWM-CIMSS, William Straka III

On May 14, 2020, Typhoon Vongfong became the first typhoon of the 2020 West Pacific season. It came ashore as a typhoon and by May 15, it had weakened to a tropical storm.

On May 14, NOAA-20 satellite imagery showed features that one would expect from a tropical system, including overshooting tops and tropospheric gravity waves. On May 14 at 1:34 p.m. EDT (1734 UTC), “NASA-NOAA’s Suomi NPP infrared satellite imagery showed the eye has now closed and convection has diminished within the eastern semicircle of the system, evident in the warming cloud tops,” said William Straka III of the University of Wisconsin-Madison, who created night-time and infrared images. “The diminished convection could also be seen in imagery as compared to yesterday, where convection completely surrounded the circulation.”

The nighttime image also showed a lightning streak on one of the southern feeder bands around Vongfong’s center. The imagery also showed that the circulation was not surrounded by convection (thunderstorms). The surface rain product showed potentially some clear air (no rain) intruding into the circulation. “The 88.0 GHz ATMS imagery from the Suomi-NPP satellite, while at lower resolution, did not show a circulation surrounded by convection. Rather, it showed just cold temperatures in the northeastern part of the storm where the convection was located,” Straka said.

On May 15 at 5 a.m. EDT (0900 UTC), Tropical storm Vongfong (Philippines designation Ambo) was located near latitude 14.1 degrees north and longitude 121.9 degrees east, about 60 nautical miles east-southeast of Manila, Philippines. Vongfong was moving to the northwest and had maximum sustained winds 60 knots (69 mph/111 kph).

Because of the impacts to the Philippines, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) are also tracking Typhoon Vongfong, which is called Ambo by PAGASA, to assess the impacts on the various islands in the path of the storm.

On May 15, PAGASA still had many warnings in effect, especially for the northern region of the Philippines as Vongfong moves through that area. Tropical cyclone wind signal number 2 is in effect for Luzon: that includes Ilocos Norte, Ilocos Sur, Apayao, Abra, Kalinga, La Union, Ifugao, Mountain Province, Benguet, Nueva Vizcaya, Quirino, Tarlac, Nueva Ecija, Aurora, Pampanga, Bulacan, Rizal, Metro Manila, Laguna, the eastern portion of Pangasinan, the western portion of Isabela, Cavite, Quezon including Pollilo Islands, Camarines Norte, western portion of Camarines Sur , Marinduque, and Batangas. Tropical cyclone wind signal number 1 is in effect for Luzon: Cagayan including Babuyan Islands, Batanes, the rest of Pangasinan, Zambales, Bataan, Oriental Mindoro, Burias Island, the rest of Camarines Sur, the rest of Isabela, and the northern portion of Albay.

Vongfong will continue to move northwest across the island of Luzon and is forecast to turn northeast and become extra-tropical.

By Rob Gutro
NASA’s Goddard Space Flight Center

90L – Atlantic Ocean

May 15, 2020 – NASA Analyzes Developing System 90L in Straits of Florida

A low-pressure area designated as System 90L appears to be developing in the Straits of Florida, located between Southern Florida and Cuba. NASA’s Aqua satellite measured cloud top temperatures within the developing system and found some stronger storms.

Aqua image of 90L — On May 15, 2020 at 3:45 a.m. EDT (0745 UTC), the MODIS instrument that flies aboard NASA’s Aqua satellite gathered infrared data on 90L. Strongest thunderstorms had cloud top temperatures (yellow) as cold as minus 50 degrees Fahrenheit (minus 45.5 Celsius) over the Straits of Florida. Credit: NASA/NRL

At 8:50 a.m. EDT on May 15, NOAA’s National Hurricane Center (NHC) issued a Special Tropical Weather Outlook issued to discuss the potential for tropical or subtropical development near the northwest Bahamas.

The Outlook stated, “A trough (elongated area) of low pressure located over the Straits of Florida continues to produce disorganized shower activity and gusty winds across the Florida Keys, portions of southeast Florida, and the northwestern Bahamas. Gradual development of this system is expected, and it will likely become a tropical or subtropical storm on Saturday [May 16] when it is located near the northwestern Bahamas. Later in the weekend and early next week, the system is expected to move generally northeastward over the western Atlantic (Ocean).”

NASA’s Aqua satellite provided information to NHC forecasters. One kind of data Aqua provides is infrared light to analyze the strength of storms by providing temperature information about the system’s clouds. The strongest thunderstorms that reach high into the atmosphere have the coldest cloud top temperatures.

On May 15 at 3:45 a.m., EDT (0745 UTC) the Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard NASA’s Aqua satellite gathered infrared data on 90L. Strongest thunderstorms had cloud top temperatures as cold as minus 50 degrees Fahrenheit (minus 45.5 Celsius). As cloud tops continue to cool, they stretch higher into the troposphere. NASA research has shown that when cloud top temperatures drop to minus 70 degrees Fahrenheit (minus 56.6 degrees Celsius), storms have the ability to generate heavy rain.

The NHC Outlook stated, “Regardless of development, the disturbance will continue to bring heavy rainfall to portions of the Florida Keys, southeast Florida and the Bahamas through Saturday. Tropical storm-force wind gusts are also possible across portions of the Florida Keys, southeast Florida, and the Bahamas during the next day or so. In addition, hazardous marine conditions are expected along the Florida east coast and in the Bahamas where Gale Warnings are in effect. Dangerous surf conditions and rip currents are possible along portions of the southeast U.S. coast this weekend and early next week.”

The NHC said that the formation chance through 48 hours and out through 5 days is high.

Tropical cyclones and hurricanes are the most powerful weather events on Earth. NASA’s expertise in space and scientific exploration contributes to essential services provided to the American people by other federal agencies, such as hurricane weather forecasting.

For updated forecasts, visit: www.nhc.noaa.gov.

By Rob Gutro
NASA’s Goddard Space Flight Center

Vongfong – Northwestern Pacific Ocean

May 14, 2020 – Satellites Eye Typhoon Vongfong Landfall in the Philippines

NASA and NOAA satellites have been providing forecasters with satellite data that showed the strength and extent of Typhoon Vongfong as it made landfall in the Philippines and continued to track through the country. Warnings were in effect throughout several areas of the Philippines on May 14.

JPSS image of Vongfong — The NOAA-20 satellite saw Typhoon Vongfong at 12:03 p.m. EDT (1703 UTC) on May 13. The imagery showed features that’s expected from an intensifying storm, including overshooting tops and tropospheric gravity waves. In addition, a clear eye could be seen as well. Credit: NOAA/William Straka III, Univ. of Wisconsin Madison

The NOAA-20 satellite saw Typhoon Vongfong at 12:03 p.m. EDT (1703 UTC) on May 13. “The imagery showed features that one would expect from an intensifying storm, including overshooting tops and tropospheric gravity waves,” said William Straka III of the University of Wisconsin- Madison, who created the imagery using the satellite data. “In addition, a clear eye could be seen as well.”

The infrared image also showed cloud top temperatures. Coldest cloud top temperatures are indicative of strongest storms because their cloud tops are pushed high into the atmosphere by strong uplift of air. NOAA-20 showed that the colder temperatures (where the convection is located) surrounds the circulation center, a sign of a mature tropical system.

The Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard NASA-NOAA’s Suomi NPP satellite provided a visible image of Typhoon Vongfong as it was making landfall in the east central Philippines on May 14. Vongfong made landfall in Samar. Samar is the third largest island in the Philippines, and is located in eastern Visayas region.

The VIIRS image showed bands of powerful thunderstorms north of the center and tightly around the center of circulation. Visible imagery has revealed that the eye has closed as the storm has started to weaken.

Warnings are posted throughout the Philippines on May 14. Tropical cyclone wind signal number #3 is in effect for Visayas: including Northern Samar and northern parts of eastern Samar and of Samar Luzon: Sorsogon, Albay, Masbate, Ticao Islands, Burias Islands, Catanduanes, southern parts of Camarines Sur. Tropical cyclone wind signal number 2 is also in effect for Visayas: for the northernmost part of Leyte, rest of Samar and rest of eastern Samar. Wind signal 2 is also in effect for Luzon: Camarines Norte, rest of Camarines Sur, southern parts of Quezon and Marinduque. Tropical cyclone wind signal number 1 covers Visayas and Luzon. In Visayas: Wind Signal 1 covers the rest of northern portion of Leyte, northeastern parts of Capiz and of Iloilo, and in Luzon: it covers Aurora, Bulacan, Metro Manila, Cavite, Laguna, Batangas, Rizal, rest of Quezon, Romblon, Bataan and Pampanga.

At 11 a.m. EDT (1500 UTC) on May 14, the Joint Typhoon Warning Center (JTWC) noted that the center of Vongfong was located near latitude 12.5 degrees north and longitude 124.5 degrees east, about 266 nautical miles east-southeast of Manila, Philippines. Vongfong was moving to the northwest and maximum sustained winds had decreased from 100 knots (115 mph/185 kph) to 85 knots (98 mph/157 kph) over the previous six hours.

The forecast from JTWC has Typhoon Vongfong weakening as it moves on a northerly track over the Visayas and Luzon regions of the Philippines, and then finally curving back into the Northwestern Pacific Ocean.

By Rob Gutro/ William Straka III
NASA’s Goddard Space Flight Center/University of Wisconsin Madison/SSEC/CIMSS

Vongfong – Northwestern Pacific Ocean

May 13, 2020 – NASA Finds Vongfong at Typhoon Strength Philippine Warnings Up

NASA’s Terra satellite revealed powerful storms in Vongfong as it ramped up from a tropical storm to a typhoon. Vongfong is known locally in the Philippines as Typhoon Ambo.

Terra image of Vongfong — On May 13 at 9:25 a.m. EDT (1325 UTC), the MODIS instrument aboard NASA’s Terra satellite gathered temperature information about Typhoon Vongfong’s cloud tops. MODIS found two large areas of powerful thunderstorms (red) where temperatures were as cold as or colder than minus 70 degrees Fahrenheit (minus 56.6 Celsius). Credit: NASA/NRL

NASA’s Terra satellite used infrared light to analyze the strength of storms in Vongfong. Infrared data provides temperature information, and the strongest thunderstorms that reach high into the atmosphere have the coldest cloud top temperatures.

On May 13 at 9:25 a.m. EDT (1325 UTC), the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard NASA’s Terra satellite gathered temperature information about Typhoon Vongfong’s cloud tops. MODIS found two large areas of powerful thunderstorms north and west of the center of circulation where temperatures were as cold as or colder than minus 70 degrees Fahrenheit (minus 56.6 Celsius). Cloud top temperatures that cold indicate strong storms with the potential to generate heavy rainfall.

Warnings in the Philippines include Tropical cyclone wind signal number #1 for the Visayas region: northern parts of Samar and northern parts of eastern Samar; and for the Luzon region: Sorsogon, Ticao Island, Catanduanes, southern parts of Albay.

At 5 a.m. EDT (0900 UTC) on May 13, 2020, the Joint Typhoon Warning Center noted that Vongfong (Ambo) was located near latitude 12.0 degrees north and longitude 128.5 degrees east, about 465 nautical miles east-southeast of Manila, Philippines. Vongfong was moving to the west-northwest and had maximum sustained winds 70 knots (80 mph/130 kph).

Vongfong is strengthening. The storm is expected to peak at 100 knots (115 mph/185 kph) as it passes east of the Visayas islands, and then begin to weaken.

Typhoons and hurricanes are the most powerful weather events on Earth. NASA’s expertise in space and scientific exploration contributes to essential services provided to the American people by other federal agencies, such as hurricane weather forecasting.

By Rob Gutro
NASA’s Goddard Space Flight Center

Vongfong – Northwestern Pacific Ocean

May 12, 2020 – NASA Sees Tropical Storm Vongfong Form and Threaten the Philippines

A low-pressure area that formed in the Northwestern Pacific Ocean several days ago has consolidated and organized into a tropical storm. NASA’s Aqua satellite provided forecasters with a visible image of newly formed Tropical Storm Vongfong.

Aqua image of Vongfong — On May 12, 2020, the MODIS instrument that flies aboard NASA’s Aqua satellite provided a visible image of newly developed Tropical Storm Vongfong, known locally in the Philippines as Ambo, in the Northwestern Pacific Ocean. Credit: NASA/BRL

Vongfong, known locally as Ambo in the Philippines, threatens that country, according to the forecasts from the Joint Typhoon Warning Center or JTWC. The storm is also the first of tropical cyclone of the Northwestern Pacific Ocean typhoon season.

On May 12, the Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard NASA’s Aqua satellite provided a visible image of Vongfong that showed the storm had a more rounded shape than it did the previous day, as it continued to consolidate. A more rounded shape in a tropical cyclone indicates it is becoming a more organized storm. Infrared satellite imagery also indicated cooling cloud top temperatures, which means that cloud tops are extending higher into the troposphere. The higher the cloud top, the stronger the uplift of air in a storm, and usually, the stronger the storm.

At 11 a.m. EDT (1500 UTC) on May 12, the JTWC noted that Vongfong had maximum sustained winds near 35 knots (40 mph/65 kph) with higher gusts. It was located near latitude 11.4 degrees north and longitude 128.8 degrees east, about 495 miles east-southeast of Manila, Philippines. Vongfong was moving to the north-northwest.

JTWC forecasters expect Vongfong (Ambo) will move west-northwest, and then later northwest before finally turning to the north. The storm is expected to strengthen to typhoon force with maximum sustained winds near 65 knots (75 mph/120 kph) as it passes over the Philippines archipelago.

PAGASA, Philippine Atmospheric, Geophysical and Astronomical Services Administration, the entity that issues forecasts and warnings for the country noted, “Between tonight and tomorrow (13 May) evening, Ambo (Vongfong) will bring scattered light to moderate with at times heavy rain showers during thunderstorms over Mindanao and Eastern Visayas. Between tomorrow evening and Thursday (14 May) evening, Ambo (Vongfong) will bring moderate to heavy rains over Eastern Visayas, Catanduanes, Albay, Sorsogon, and Masbate. Tropical Cyclone Wind Signal (TCWS) #1 may be raised over Eastern Samar and the eastern portion of Northern Samar in the next 6 to 12 hours in anticipation of strong winds associated with the approaching tropical storm.”

NASA’s Aqua satellite is one in a fleet of NASA satellites that provide data for hurricane research.

For additional forecasts and updates from PAGASA, visit: http://bagong.pagasa.dost.gov.ph/

By Rob Gutro
NASA’s Goddard Space Flight Center

1E – Eastern Pacific Ocean

Apr. 27, 2020 – NASA Catches Formation and Final Fate of Eastern Pacific’s Tropical Depression 1E

The Eastern Pacific Ocean’s hurricane season may not officially start until mid-May, but the first tropical cyclone of the season formed over the weekend of April 25 and 26. NASA’s Aqua satellite provided an infrared look at the small depression when it was at its peak and before it became post-tropical.

Aqua image of 1E — NASA’s Aqua satellite passed over Tropical Depression 1E on Sunday, April 26, 2020 at 5 a.m. EDT (0900 UTC) and the MODIS instrument aboard analyzed 1E in infrared light to determine temperature of cloud tops in storms. MODIS found cloud top temperatures as cold as minus 50 degrees Fahrenheit in the depression, not cold enough to suggest heavy rainfall. Credit: NASA/NRL

Tropical Depression 1E formed on Saturday, April 25 and by the next day, it was not in a favorable environment for further development, according to the National Hurricane Center (NHC). NASA’s Aqua satellite provided forecasters with a look at 1E’s cloud top temperatures to assess the strength of the storm.

NASA’s Aqua satellite passed over Tropical Depression 1E on Sunday, April 26, 2020 at 5 a.m. EDT (0900 UTC) and the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard analyzed 1E in infrared light. Infrared light is used to determine temperature of cloud tops in storms, and the colder the cloud top, the higher it is in the troposphere (lowest layer of the atmosphere), and the stronger the storm tends to be. MODIS found cloud top temperatures as cold as minus 50 degrees Fahrenheit in the depression, not cold enough to suggest heavy rainfall.

On April 26, the National Hurricane Center (NHC) reported, “Deep convection has been waning quickly in the southeastern quadrant since the previous advisory, and the system barely met criteria for identifying it as a tropical cyclone at 1200 UTC (8 a.m. EDT).”

NHC said at 11 a.m. EDT (8 a.m. PDT) the center of Tropical Depression 1E was located near latitude 15.7 north, longitude 118.8 west. At that time, 1E reached its peak with maximum sustained winds near 35 mph (55 kph). The system weakened throughout the day and overnight as it encountered, “Deep-layer dry air and cooler sea-surface temperatures, combined with strong westerly shear of 25 to 30 knots,” NHC noted.

On Monday, April 27, 2020, the NHC said that post-tropical remnant low 1E was far from land areas as it continued to degenerate. It was centered near latitude 17 degrees north and longitude 121 degrees west. The estimated minimum central pressure was 1010 millibars. Maximum sustained winds were 25 knots (29 mph/46 kph).

A post-tropical storm is a generic term for a former tropical cyclone that no longer possesses sufficient tropical characteristics to be considered a tropical cyclone. Former tropical cyclones can become fully extratropical, subtropical, or remnant lows, which are three classes of post-tropical cyclones. In any case, they no longer possesses sufficient tropical characteristics to be considered a tropical cyclone. However, post-tropical cyclones can continue carrying heavy rains and high winds.

This system was only retaining shallow convection. It continued to weaken as it moved toward the west-northwest. NHC expects the system to dissipate by Tuesday, April 28.

Hurricane season officially begins on May 15 in the Eastern Pacific Ocean, so this depression was early for season. For more information about NHC, visit: www.nhc.noaa.gov.

Typhoons/ hurricanes are the most powerful weather events on Earth. NASA’s expertise in space and scientific exploration contributes to essential services provided to the American people by other federal agencies, such as hurricane weather forecasting.

The MODIS instrument is one of six instruments flying on board NASA’s Aqua satellite which launched on May 4, 2002.

By Rob Gutro
NASA’s Goddard Space Flight Center

Jeruto – Southern Indian Ocean

Apr. 16, 2020 – NASA Finds Tropical Storm Jeruto’s Displaced Rainfall

NASA analyzed weakening Tropical Storm Jeruto’s rainfall and found one small area of moderate rainfall displaced from the center, because of strong wind shear.

GPM image of Jeruto — The GPM core satellite passed over Tropical Storm Jeruto on April 16 at 12:06 a.m. EDT (0406 UTC). Winds pushed the heaviest rainfall (pink) east of the center, where it was falling at a rate of 1.6 inches (40 mm) per hour in a small area. Credit: NASA/JAXA/NRL

In general, wind shear is a measure of how the speed and direction of winds change with altitude. Outside winds were pushing against the storm and displacing the heaviest rainfall east of the center.

On April 15 at 5 p.m. EDT (2100 UTC), The Joint Typhoon Warning Center noted that Tropical Storm Jeruto was barely holding onto tropical storm status with maximum sustained winds near 35 knots (40 mph/65 kph). Jeruto was located near latitude 16.2 degrees south and longitude 83.1 degrees east, about 828 nautical miles southeast of Diego Garcia.

Seven hours later, NASA gathered data on the precipitation occurring in the weakening storm. NASA has the unique capability of peering under the clouds in storms and measuring the rate in which rain is falling. The Global Precipitation Measurement mission or GPM core passed over Jeruto from its orbit in space and measured rainfall rates in the storm on April 16 at 12:06 a.m. EDT (0406 UTC). Winds pushed the heaviest rainfall east of the center, where it was falling at a rate of 1.6 inches (40 mm) per hour in a small area.

Jeruto is expected to dissipate on April 16.

Both the Japan Aerospace Exploration Agency, JAXA and NASA manage GPM.

By Rob Gutro
NASA’s Goddard Space Flight Center

Jeruto – Southern Indian Ocean

Apr. 15, 2020 – NASA Finds Tropical Storm Jeruto Develop in Southern Indian Ocean

The latest tropical cyclone to develop in the Southern Indian Ocean is no threat to land areas. NASA-NOAA’s Suomi NPP satellite provided forecasters with a visible image of Tropical Storm Jeruto on April 15, 2020.

Suomi NPP Image of Jeruto — NASA-NOAA’s Suomi NPP satellite provided forecasters with a visible image of Tropical Storm Jeruto on April 15 shortly after it developed in the Southern Indian Ocean. Credit: NASA Worldview, Earth Observing System Data and Information System (EOSDIS)

Visible imagery from NASA satellites help forecasters understand if a storm is organizing or weakening. The visible image created by the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard Suomi NPP showed Jeruto was being affected by wind shear after it developed. Vertical wind shear, that is, winds outside of a tropical cyclone at different heights in the atmosphere (the troposphere) push against a tropical cyclone and tear it apart.

The shape of a tropical cyclone provides forecasters with an idea of its organization and strength, and NASA-NOAA’s Suomi NPP satellite showed the storm appeared elongated, as outside winds were pushing clouds away from the center of circulation.

On April 15 at 5 a.m. EDT (0900 UTC), Jeruto’s center was located near latitude 15.8 degrees south and longitude 84.3 degrees east. Jeruto was moving west-southwest near 10 knots (12 mph/19 kph). Maximum sustained winds were near 40 knots (46 mph/76 kph).

The Joint Typhoon Warning Center noted vertical wind shear (wind speeds) will increase and will likely dissipate the storm within a couple of days.

By Rob Gutro
NASA’s Goddard Space Flight Center