Nov. 02, 2018 – NASA Finds Tropical Depression Yutu Fading off China Coast
Once a Super Typhoon, now a ghost of its former self, Tropical Depression Yutu was fading off the coast of southeastern China on Nov.2 when NASA’s Aqua satellite passed overhead.
NASA’s Aqua satellite captured this image of Tropical Depression Yutu fading off the coast of southeastern China on Nov. 2. Credit: NASA Worldview, Earth Observing System Data and Information System (EOSDIS)
The MODIS instrument or Moderate Resolution Imaging Spectroradiometer that flies aboard NASA’s Aqua satellite captured a visible image of Yutu on Nov. 2. Although the storm weakened to a depression, the center of circulation was still apparent on the MODIS imagery. The center was surrounded by wispy clouds and the bulk of clouds and any precipitation was falling north of the center and over China.
On Thursday, Nov. 1 at 11 p.m. EDT (0300 UTC on Nov. 2) Yutu’s maximum sustained winds were near 25 knots (28.7 mph/46.3 kph).
It was centered at 20.7 north latitude and 116.2 east longitude, about 155 nautical miles southeast of Hong Kong, China. Yutu was crawling to the northwest.
The Joint Typhoon Warning Center (JTWC) forecasts Yutu to dissipate by the end of the day.
Typhoon Yutu produced heavy rainfall as it passed over the island of Luzon in the northern Philippines. The Global Precipitation Measurement mission or GPM core satellite provided data on that rainfall. The storm has since weakened to a tropical storm and triggered warnings in China.
The GPM core observatory satellite observed Tropical Storm Yutu on October 31, 2018 at 0210 UTC (Oct. 30 at 10:10 p.m. EDT) as it passed directly above the center of circulation in the South China Sea. GPM showed very little rainfall was occurring near the low level center of circulation. Extremely heavy rainfall was found in powerful storms located northwest and southeast of Yutu’s center where rain was falling at greater than 183 mm (7.2 inches) per hour. Storm top heights were reaching altitudes above 15.5 km (9.6 miles) in the tallest convective storms northwest of Yutu’s center. Credit: NASA/JAXA, Hal Pierce
At least nine deaths have been attributed to the typhoon. Heavy rainfall caused a landslide in the town of Natonin where up to 24 people are still missing. As expected, the typhoon weakened as is passed over the mountainous terrain of northern Luzon.
The GPM core observatory satellite had an excellent view of Tropical Storm Yutu on October 31, 2018 at 0210 UTC (Oct. 30 at 10:10 p.m. EDT) as it passed directly above the center of circulation. At the time GPM passed overhead, Tropical Storm Yutu had maximum sustained winds of about 55 knots (63 mph) and was moving over the South China Sea. A rainfall analysis based on GPM’s Microwave Imager (GMI) and Dual-Frequency Precipitation Radar (DPR) instruments showed that very little rainfall was occurring near the tropical storm’s low level center of circulation. Extremely heavy rainfall was found by the satellite’s radar in powerful storms located northwest and southeast of Yutu’s center of circulation. GPM’s radar (DPR Ku Band) measured precipitation in those areas falling at the exceptional rate of greater than 183 mm (7.2 inches) per hour.
At NASA’s Goddard Space Flight Center in Greenbelt, Md. a 3D view of tropical storm Yutu was constructed using data from GPM’s radar (DPR Ku Band). The image, looking from the south showed the vertical structure of precipitation within the tropical storm. Those data revealed that storm top heights were reaching altitudes above 15.5 km (9.6 miles) in the tallest convective storms that were located well to the northwest of Yutu’s center of circulation. GPM is a joint mission between NASA and the Japan Aerospace Exploration Agency, JAXA.
The GPM core observatory satellite observed Tropical Storm Yutu on October 31, 2018 at 0210 UTC (Oct. 30 at 10:10 p.m. EDT) as it passed directly above the center of circulation in the South China Sea. GPM showed very little rainfall was occurring near the low level center of circulation. Extremely heavy rainfall was found in powerful storms located northwest and southeast of Yutu’s center where rain was falling at greater than 183 mm (7.2 inches) per hour. Storm top heights were reaching altitudes above 15.5 km (9.6 miles) in the tallest convective storms northwest of Yutu’s center. Credit: NASA/JAXA, Hal Pierce
On Nov. 1, the Hong Kong Observatory posted a Tropical Cyclone Warning Bulletin on Yutu 21:45 HKT (9:45 a.m. EDT) and noted that the Strong Wind Signal, No. 3 is in force. This means that winds with mean speeds of 41 to 62 kilometers (25 to 39 mph) per hour are expected.
On Nov. 1 at 11 a.m. EDT (1500 UTC), the Joint Typhoon Warning Center noted that satellite imagery shows disorganized deep convection (developing thunderstorms) becoming displaced to the northeast of a poorly defined low-level circulation center.” At that time, Tropical Storm Yutu had maximum sustained winds near 40 knots (46 mph/74 kph). It was centered near 20.7 degrees north latitude and 116.3 degrees east longitude. Tropical storm Yutu was located approximately 160 nautical miles southeast of Hong Kong, China and was moving north.
The bulk of clouds and precipitation is being pushed to the northeast from strong wind shear. In general, wind shear is a measure of how the speed and direction of winds change with altitude. In order to understand how it affects a tropical cyclone or hurricane, think of a tropical cyclone as a vertical rotating cylinder. The different levels of rotating winds in the center of Tropical cyclones need to be stacked on top each other for the storm to strengthen. If there are outside winds pushing against the cylinder near the top, it affects the balance of the entire cylinder and that’s what happens when vertical wind shear pushes against a storm. It pushes the center and weakens (or wobbles) the rotation of the entire cylinder (storm).
The Joint Typhoon Warning Center (JTWC) predicts that Tropical Storm Yutu will turn toward the northwest, gradually weaken and dissipate as it moves toward Hong Kong.
Nov. 01, 2018 – NASA Sees Hurricane Oscar Transitioning To Extratropical Low
Hurricane Oscar has transitioned into an extra-tropical low pressure area in the northeastern Atlantic Ocean. The Global Precipitation Measurement mission or GPM core satellite provided a look at rainfall occurring within the storm.
On October 31, 2018 at 8:43 a.m. EDT (1243 UTC) the GPM core observatory satellite showed the heaviest convective rainfall was located well northwest of Oscar’s low level center of circulation. Rain was falling at a rate of about 2 inches (50.8 mm) per hour in that area. On the western side, few storm tops were reaching heights above 5.6 miles (9.0 km) but contained heavy downpours. Credit: NASA/JAXA, Hal Pierce
When a storm becomes extra-tropical, it means that a tropical cyclone has lost its “tropical” characteristics. The National Hurricane Center defines “extra-tropical” as a transition that implies both poleward displacement (meaning it moves toward the north or south pole) of the cyclone and the conversion of the cyclone’s primary energy source from the release of latent heat of condensation to baroclinic (the temperature contrast between warm and cold air masses) processes. It is important to note that cyclones can become extratropical and still retain winds of hurricane or tropical storm force.
On October 31, 2018 at 8:43 a.m. EDT (1243 UTC) the GPM core observatory satellite had a pass over hurricane Oscar. The hurricane had maximum sustained winds of about 74.8 mph (65 knots) and was moving toward the northeast while becoming more extratropical in appearance. GPM’s Microwave Imager (GMI) showed that the heaviest convective rainfall was located well northwest of the low level center of circulation. Rain was falling at a rate of about 2 inches (50.8 mm) per hour in that area.
On October 31, 2018 at 8:43 a.m. EDT (1243 UTC) the GPM core observatory satellite showed the heaviest convective rainfall was located well northwest of Oscar’s low level center of circulation. Rain was falling at a rate of about 2 inches (50.8 mm) per hour in that area. On the western side, few storm tops were reaching heights above 5.6 miles (9.0 km) but contained heavy downpours. Credit: NASA/JAXA, Hal Pierce
At NASA’s Goddard Space Flight Center in Greenbelt, Md. a simulated 3-D view was created from GPM data looking from the east toward the storm. The image was derived from GPM’s radar (DPR Ku Band) data. GPM’s radar swath (DPR Ku Band) passed through storms on Oscar’s western side. GPM’s DPR found that very few storm tops were reaching heights above 5.6 miles (9.0 km) but heavy downpours were returning strong radar reflectivity values to the GPM satellite. Radar reflectivity values were frequently observed in the 3D cross-section through heavy rainfall in the northwestern side of the hurricane. GPM is a joint mission between NASA and the Japan Aerospace Exploration Agency, JAXA.
Oscar is now an extra-tropical low pressure area and is expected to pass northwest of Ireland over the weekend of Nov. 3 and 4 and will bring winds and rain to the country.
Oct. 31, 2018 – NASA Gets An Infrared View of Hurricane Oscar
NASA’s Aqua satellite passed over the North Atlantic Ocean and gathered temperature data on Hurricane Oscar. The data showed the bulk of strong storms were in the northwestern quadrant as Oscar began transitioning into an extra-tropical storm.
At 2:15 a.m. EDT (0615 UTC) on Oct. 31, the MODIS instrument that flies aboard NASA’s Aqua satellite gathered infrared data on Hurricane Oscar. Strongest thunderstorms circled the center and were in a thick band west of center where cloud top temperatures were as cold as minus 63 degrees Fahrenheit (minus 53 Celsius). Credit: NASA/NRL
On Oct. 31 at 2:15 a.m. EDT (0615 UTC) the MODIS instrument that flies aboard NASA’s Aqua satellite gathered infrared data on Oscar. Infrared data provides temperature information. Strongest thunderstorms were west and northwest of the center where MODIS found cloud top temperatures as cold as minus 63 degrees Fahrenheit (minus 53 Celsius). NASA research has shown that cloud tops with temperatures that cold were high in the troposphere and have the ability to generate heavy rain.
At 5 a.m. EDT (0900 UTC) on Oct. 31 the center of Hurricane Oscar was located near latitude 34.1 degrees north and longitude 53.6 degrees west. That’s about 660 miles (1,060 km) east-northeast of Bermuda. Oscar is moving toward the northeast near 22 mph (35 kph). A faster north-northeast to northeast motion is expected during the next few days. Maximum sustained winds have decreased to near 75 mph (120 kph) with higher gusts. The estimated minimum central pressure is 982 millibars.
The National Hurricane Center noted at 11 a.m. EDT (1500 UTC), “Oscar is quickly transforming into an extratropical low. Although there is still a little bit of deep convection just north of the center, a more prominent cloud shield extends northward from the western part of the circulation.”
NOAA’s GOES-16 satellite imagery showed Oscar’s center nearly embedded within a frontal zone and cold air moving into the back side of the system.
Oscar is expected to become an extratropical low over the north-central Atlantic Ocean by tonight, Oct. 31 (EDT). Although gradual weakening is expected during the next several days, Oscar is expected to remain a powerful post-tropical cyclone over the north-central and northeastern Atlantic Ocean into the weekend.
Although far from land, large swells generated by Oscar will affect Bermuda through Wednesday, Oct. 31.
Oct. 31, 2018 -NASA’s CloudSat Gets a Slice of Typhoon Yutu’s Eye
NASA’s CloudSat satellite captured a stunning image of Typhoon Yutu as it passed over the eye of the storm. The storm has since weakened to a tropical storm.
CloudSat flew over the eye of Typhoon Yutu on October 28, 2018 at 12:58 a.m. EDT (0458 UTC) as the storm was approaching the Philippines in the Western North Pacific. Yutu revealed the cirrus free eye with an outward sloping eyewall, a feature typically found in intense tropical systems. Intense areas of convection with moderate to heavy rainfall (deep red and pink colors), cloud-free areas (moats) underneath the northern portion of the cirrus canopy and cloud top height’s estimated at 14 kilometers. Lower values of reflectivity (areas of green and blue) denote smaller ice and water particle sizes typically located at top of the system (in the anvil area). Credit: Colorado State/Natalie Tourville
CloudSat flew over the eye of Typhoon Yutu on October 28, 2018 at 12:58 a.m. EDT (0458 UTC) as the storm was approaching the Philippines in the Western North Pacific. At the time of the CloudSat overpass, Typhoon Yutu was beginning a period of weakening as the storm was moving info less favorable atmospheric conditions (lower sea surface temperatures). Typhoon Yutu contained estimated sustained winds of 120 knots (138 mph) with a minimum pressure of 933 millibars (the equivalent of a Category 4 strength storm). Typhoon Yutu left a trail of destruction through Saipan, Tinian and the Mariana Islands on October 24 and 25, 2018 as a Super Typhoon (category 5 strength storm).
Natalie Tourville of Colorado State University who produced the images, said “CloudSat’s 94 GHz cloud profiling radar (CPR) passed directly over the eye of Typhoon Yutu revealing the cirrus free eye with an outward sloping eyewall, a feature typically found in intense tropical systems. The southern portion of the eyewall appears more disorganized as the thicker cloud tops are starting to disintegrate from the top down.
CloudSat flew over the eye of Typhoon Yutu on October 28, 2018 at 12:58 a.m. EDT (0458 UTC) as the storm was approaching the Philippines in the Western North Pacific. Yutu revealed the cirrus free eye with an outward sloping eyewall, a feature typically found in intense tropical systems. Intense areas of convection with moderate to heavy rainfall (deep red and pink colors), cloud-free areas (moats) underneath the northern portion of the cirrus canopy and cloud top height’s estimated at 14 kilometers. Lower values of reflectivity (areas of green and blue) denote smaller ice and water particle sizes typically located at top of the system (in the anvil area). Credit: Colorado State/Natalie Tourville
The CloudSat overpass reveals the inner details beneath the storms cloud tops. Intense areas of convection with moderate to heavy rainfall, cloud-free areas (moats) underneath the northern portion of the cirrus canopy and cloud top height’s estimated at 14 kilometers (8.7 miles). Lower values of reflectivity denote smaller ice and water particle sizes typically located at top of the system (in the anvil area). The CloudSat CPR signal attenuates in heavy rainfall when cloud droplets become larger than 3 millimeters (.11 inch) which dampen the strength of the CPR signal. This is evident by the lack of signal typically occurring beneath the melting level when frozen particles transform into liquid.”
On Oct. 31 at 5 a.m. EDT (0900 UTC) Yutu had weakened to a tropical storm with maximum sustained winds near 45 knots (52 mph/83 kph). Tropical storm Yutu was centered near 18.1 degrees north latitude and 117.5 degrees east longitude, about 291 nautical miles northwest of Manila, Philippines.
As Yutu moves toward China, Hong Kong has posted Stand-by signal #1. The Joint Typhoon Warning Center expects Yutu to re-strengthen as it moves north. The storm is forecast to dissipate off the Chinese mainland, east of Hong Kong.
Oct. 30, 2018 – Hurricane Oscar on Satellite Imagery: A One-Eyed Little Monster with a Tail
Of course, tropical cyclones have one eye and with Halloween on the horizon, false-colored infrared imagery from NASA’s Aqua satellite brought out that eye in this small tropical monster with a tail of thunderstorms.
NASA’s Aqua satellite showed cloud top temperatures in strongest storms around Oscar’s eye were as cold as or colder than minus 70 degrees (red) Fahrenheit (minus 56.6 degrees Celsius). A fragmented band of thunderstorms wrapping into the center of circulation from the southeast gave the storm an appearance of having a tail. Credit: NASA/NRL
When NASA’s Aqua satellite passed over the Central Atlantic Ocean, it took Hurricane Oscar’s cloud top temperatures that helped forecasters key into where the strongest side of the storm was located.
Cloud top temperatures determine strength of the thunderstorms that make up a tropical cyclone. The colder the cloud top, the stronger the uplift in the storm that helps thunderstorm development. Basically, infrared data helps determine where the most powerful storms are within a tropical cyclone.
The Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard Aqua provided that infrared data on Oct. 30 at 1:40 a.m. EDT (0540 UTC) MODIS data showed cloud top temperatures in strongest storms around Oscar’s eye were as cold as or colder than minus 70 degrees Fahrenheit (minus 56.6 degrees Celsius). NASA research indicates very cold cloud tops with the potential to generate very heavy rainfall.
The National Hurricane Center or NHC said ” Cloud-top temperatures have warmed a bit overall, and the convective pattern is becoming more asymmetric as dry air is infiltrating the southern and eastern part of Oscar’s circulation. However, the hurricane is still producing plenty of inner-core convection and some lightning strikes.”
A fragmented band of thunderstorms wrapping into the center of circulation from the southeast gave the storm an appearance of having a tail.
MODIS imagery also showed that Oscar is a small storm. Hurricane-force winds extend outward up to 25 miles (35 km) from the center, and tropical-storm-force winds extend outward up to 90 miles (150 km).
At 11 a.m. EDT (1500 UTC) on Oct. 30 the center of Hurricane Oscar was located near latitude 29.7 North, longitude 57.7 West. Oscar is moving toward the north-northeast near 14 mph (22 kph). A north-northeastward or northeastward motion with an increase in forward speed is expected through Friday. Maximum sustained winds are near 100 mph (155 kph) with higher gusts. The estimated minimum central pressure is 972 millibars.
Gradual weakening is forecast during the next several days, but Oscar is expected to become a powerful extratropical low over the north-central Atlantic Ocean by late Wednesday, Oct. 31.
Oct. 30, 2018 – NASA’s Aqua Satellite Captures Typhoon Yutu Exiting the Northern Philippines
Visible satellite imagery from NASA’s Aqua satellite showed that Typhoon Yutu maintained its structure as it exited Luzon, the northern Philippines.
At 1:05 a.m. EDT (0505 UTC) on Oct. 30, the MODIS instrument aboard Aqua captured a visible image of Yutu as it was exiting then northern Philippines and entering the South China Sea. Visible satellite imagery showed the storm maintained a symmetrical structure despite passing over land. Credit: NASA/NRL
Yutu is known locally as Rosita in the Philippines. On Oct. 30, Yutu moved into the South China Sea after passing through La Union. La Union is a province in the Ilocos Region in the island of Luzon.
Philippines warnings that are in effect on Oct. 30 include Warning signal 3 over the Luzon provinces of La Union and Pangasinan; Warning signal 2 over the Luzon provinces of Abra, Ilocos Sur, Mt Province, Nueva Vizcaya, Nueva Ecija, Tarlac and Zambales; and Warning signal 1 over the Luzon provinces of Ilocos Norte, Apayao, Kalinga, Cagayan, Isabela, Quirino, Aurora, Bulacan, Pampanga, Bataan, Metro Manila, Rizal, Cavite, Laguna and Batangas.
At 1:05 a.m. EDT (0505 UTC) on Oct. 30, the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard Aqua captured a visible image of Yutu as it was exiting then northern Philippines and entering the South China Sea. Visible satellite imagery showed the storm maintained a symmetrical structure despite passing over land.
At 5 a.m. EDT (0900 UTC) on Oct. 30, the center of Yutu was located near latitude 16.8 degrees north and longitude 120.0 degrees east. That’s 144 nautical miles north-northeast of Manila, Philippines. Maximum sustained winds were near 75 knots (86 mph/139 kph).
The Joint Typhoon Warning Center expects Yutu to re-strengthen in the South China Sea and then turn north. It is expected to dissipate in the Taiwan Strait, located between Taiwan and the Chinese mainland.
Typhoon Yutu, known as Rosita in the Philippines, is now threatening the Philippine Island of Luzon. The Global Precipitation Measurement mission or GPM core satellite provided a look at the heavy rainfall the storm is packing.
The GPM core observatory satellite passed above the Philippine Sea on Oct. 29, 2018 at 0212 UTC (Oct. 28 at 10:12 p.m. EDT). Those GPM data revealed that heavy rainfall within the typhoon covered an area the size of Luzon. Extreme precipitation falling at a rate of over 178 mm (7 inches) per hour was also revealed by GPM’s radar (DPR Ku Band) within powerful storms in Yutu’s southwestern eye wall. Credit: NASA/JAXA, Hal Pierce
On Oct. 24, 2018 Yutu devastated the Northern Mariana Islands of Tinian and Saipan as a super typhoon. One death has been attributed to the typhoon in the Mariana with many structures including schools and hospitals being destroyed. Typhoon Yutu weakened as it moved toward the Philippines and had maximum sustained winds of about 90 knots (103.5 mph) when the GPM core observatory satellite passed above the Philippine Sea on Oct. 29, 2018 at 0212 UTC (Oct. 28 at 10:12 p.m. EDT).
By 11 a.m. EDT (1500 UTC) on Oct. 29, Yutu’s maximum sustained winds remained at the same strength as they were earlier. Yutu was located near 16.7 degrees north latitude and 123.6 east longitude. That’s about 224 nautical miles northeast of Manila, Philippines.
The GPM core observatory satellite passed above the Philippine Sea on Oct. 29, 2018 at 0212 UTC (Oct. 28 at 10:12 p.m. EDT). Those GPM data revealed that heavy rainfall within the typhoon covered an area the size of Luzon. Extreme precipitation falling at a rate of over 178 mm (7 inches) per hour was also revealed by GPM’s radar (DPR Ku Band) within powerful storms in Yutu’s southwestern eye wall. Credit: NASA/JAXA, Hal Pierce
At NASA’s Goddard Space Flight Center in Greenbelt, Maryland, a rainfall analysis was developed using data collected by GPM’s Microwave Imager (GMI) and Dual-Frequency Precipitation Radar (DPR) instruments. Those GPM data revealed that heavy rainfall within the typhoon covered an area the size of Luzon. Extreme precipitation falling at a rate of over 178 mm (7 inches) per hour was also revealed by GPM’s radar (DPR Ku Band) within powerful storms in Yutu’s southwestern eye wall.
The GPM mission is managed by both NASA and the Japan Aerospace Exploration Agency, JAXA.
The GPM core observatory satellite passed above the Philippine Sea on Oct. 29, 2018 at 0212 UTC (Oct. 28 at 10:12 p.m. EDT). Those GPM data revealed that heavy rainfall within the typhoon covered an area the size of Luzon. Extreme precipitation falling at a rate of over 178 mm (7 inches) per hour was also revealed by GPM’s radar (DPR Ku Band) within powerful storms in Yutu’s southwestern eye wall. Credit: NASA/JAXA, Hal Pierce
The Joint Typhoon Warning Center (JTWC) predicts that typhoon Yutu will still be a powerful typhoon with winds of about 85 knots (98 mph) when it makes landfall in the Philippines. Interaction with the rugged terrain over Luzon is expected to cause Yutu to weaken to tropical storm intensity. Yutu is then expected to intensify to typhoon again as it moves into the South China Sea. Typhoon Yutu is then expected to re-curve to the east of Hong Kong.
Oct. 29, 2018 – Atlantic’s Hurricane Oscar’s Water Vapor Measured by NASA’s Terra Satellite
When NASA’s Terra satellite passed over the Central Atlantic Ocean on Oct. 16 the MODIS instrument aboard analyzed water vapor within Tropical Storm Oscar.
NASA’s Terra satellite passed over Hurricane Oscar in the Atlantic Ocean On Oct. 29 at 10:20 a.m. EDT (1420). The MODIS instrument showed highest concentrations of water vapor (brown) and coldest cloud top temperatures were around the center (over water) and in the eastern quadrant. Credits: NASA/NRL
Oscar formed as a subtropical storm in the central North Atlantic Ocean on Friday, Oct. 26 at 11 p.m. EDT. Over the weekend of Oct. 27 and 28, Oscar took on tropical characteristics and strengthened into a hurricane.
On Oct. 29 at 10:20 a.m. EDT (1420) NASA’s Terra satellite passed over Oscar and provided visible and water vapor imagery of the newest Atlantic Hurricane.
Water vapor analysis of tropical cyclones tells forecasters how much potential a storm has to develop and shows where the heaviest rainfall may be found. Water vapor releases latent heat as it condenses into liquid. That liquid becomes clouds and thunderstorms that make up a tropical cyclone. Temperature is important when trying to understand how strong storms can be. The higher the cloud tops, the colder and the stronger they are.
NASA’s Terra satellite passed over Hurricane Oscar in the Atlantic Ocean On Oct. 29 at 10:20 a.m. EDT (1420). The MODIS instrument showed a clear eye surrounded by powerful thunderstorms. Fragmented bands of thunderstorms in the eastern quadrant. Credits: NASA/NRL
The Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard Terra gathered water vapor content and temperature information. The MODIS image showed highest concentrations of water vapor and coldest cloud top temperatures circled the center and extended east. MODIS saw coldest cloud top temperatures were as cold as minus 70 degrees Fahrenheit (minus 56.6 degrees Celsius) in those areas. Storms with cloud top temperatures that cold have the capability to produce heavy rainfall.
Visible imagery from MODIS showed a clear eye surrounded by powerful thunderstorms. Fragmented bands of thunderstorms in the eastern quadrant.
The National Hurricane Center said “Oscar’s convective cloud pattern has continued to improve since the previous advisory, with a small, cloud-filled eye now apparent in visible satellite imagery and also in a recent microwave pass. In addition, cirrus outflow has been expanding in all quadrants, especially in the eastern semicircle.”
The National Hurricane Center or NHC said at 11 a.m. EDT (1500 UTC) the eye of Hurricane Oscar was located near latitude 25.8 degrees north and longitude 58.4 degrees west. That’s about 590 miles (955 km) southeast of Bermuda. Oscar is moving toward the west-northwest near 7 mph (11 kph). A turn toward the northwest at a slower forward speed is expected later today, followed by a motion toward the north tonight. Maximum sustained winds have increased to near 85 mph (140 kph) with higher gusts. Additional strengthening is forecast through Tuesday, followed by gradual weakening thereafter. The estimated minimum central pressure is 981 millibars.
On Tuesday, Oct. 30, Oscar is forecast to begin moving toward the north-northeast with an increase in forward speed. The hurricane is then expected to accelerate quickly toward the northeast through the middle of the week.
NASA uses satellite data to calculate the amount of rainfall generated from tropical cyclones, and used that capability for the Eastern Pacific Ocean’s Hurricane Willa.
A rainfall accumulation analysis was generated by totaling Integrated Multi-satellitE Retrievals for GPM (IMERG) data for the period from October 20 to 26, 2018. Hurricane Willa’s approximate 0000Z and 1200Z locations are shown on this analysis. Willa produced rainfall totals greater than 20 inches (508 mm) in the Pacific Ocean off Mexico’s coast. IMERG data also indicated that rainfall accumulations of over 15 inches (381 mm) occurred in parts of Mexico and Southeastern Texas. Credit: NASA/JAXA, Hal Pierce
Tropical Depression 24E formed on October 20, 2018 and later in the day became tropical storm Willa. The tropical depression rapidly intensified and was a category five hurricane with winds of over 161 mph (140 knots) on October 22. Willa had weakened to category three intensity when it made landfall in Sinaloa, Mexico on October 24, 2018. Moisture streaming from Willa’s remnants added to the soaking of the already water logged state of Texas. Moisture from Willa’s remnants contributed to storms over the Southeast and to the developing Nor’easter moving over the East Coast.
At NASA’s Goddard Space Flight Center in Greenbelt, Maryland a rainfall accumulation analysis was generated by totaling Integrated Multi-satellitE Retrievals for GPM (IMERG) data for the period from October 20 to 26, 2018. The IMERG rainfall accumulation data indicated that Willa produced rainfall totals greater than 20 inches (508 mm) in the Pacific Ocean off Mexico’s coast. IMERG data also indicated that rainfall accumulations of over 15 inches (381 mm) occurred in parts of Mexico and Southeastern Texas.
A rainfall accumulation analysis was generated by totaling Integrated Multi-satellitE Retrievals for GPM (IMERG) data for the period from October 20 to 26, 2018. Hurricane Willa’s approximate 0000Z and 1200Z locations are shown on this analysis. Willa produced rainfall totals greater than 20 inches (508 mm) in the Pacific Ocean off Mexico’s coast. IMERG data also indicated that rainfall accumulations of over 15 inches (381 mm) occurred in parts of Mexico and Southeastern Texas. Credit: NASA/JAXA, Hal Pierce
IMERG data are generated every half hour by NASA’s Precipitation Processing System by merging data from the satellites in the GPM Constellation, and calibrating those data with measurements from the GPM Core Observatory as well as rain gauge networks around the world. IMERG data are provided for much of the globe. Full coverage is calculated over latitudes from 60 degrees north to 60 degrees south with the remaining areas of the globe being partially covered.
The Integrated Multi-satellitE Retrievals for GPM (IMERG) creates a merged precipitation product from the GPM constellation of satellites. These satellites include DMSPs from the U.S. Department of Defense, GCOM-W from the Japan Aerospace Exploration Agency (JAXA), Megha-Tropiques from the Centre National D’etudies Spatiales (CNES) and Indian Space Research Organization (ISRO), NOAA series from the National Oceanic and Atmospheric Administration (NOAA), Suomi-NPP from NOAA-NASA, and MetOps from the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT). All of the instruments (radiometers) onboard the constellation partners are intercalibrated with information from the GPM Core Observatory’s GPM Microwave Imager (GMI) and Dual-frequency Precipitation Radar (DPR).
GPM is a joint mission between NASA and the Japan Aerospace Exploration Agency, JAXA.
