Mar. 25, 2019 – Rare Tropical Storm Forms in the South Atlantic
A rare tropical storm formed in the South Atlantic off the southeast coast of Brazil on March 24, 2019. Iba is the first named tropical storm in the South Atlantic since 2010. Only one known hurricane has ever been recorded in the South Atlantic. Hurricane Catarina made landfall over the state of Santa Catarina, Brazil, as a Category 1 storm on March 27, 2004. The lack of tropical cyclones in the region is generally attributed to cool sea surface temperatures and strong vertical wind shear according to the National Hurricane Center.
March 22, 2019 – NASA’s IMERG Calculates Excessive Mozambique Rainfall from Cyclone Idai
Tropical Cyclone Idai brought heavy rainfall and deadly flooding to Mozambique. Idai made landfall directly on top of the City of Beira in Mozambique. This City is home to more than 500,000 people who have been impacted by flooding and other damage caused by the cyclone.
The Precipitation Processing System (PPS) at NASA’s Goddard Space Flight Center in Greenbelt, Md. processes and creates the realtime IMERG data products. This Global Precipitation Measurement mission or GPM IMERG animation, created at NASA shows accumulated precipitation for the region from March 3 to 19. IMERG showed over 20 inches of rain fell in some areas. The other piece of analysis is that the early precipitation saturated the soil, which made the flooding worse when the cyclone turned around and made landfall.
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).
March 22, 2019 – NASA Catches Development of Tropical Cyclone Joaninha
Visible imagery from NASA’s Terra satellite showed Tropical Cyclone Joaninha in the Southern Indian Ocean, far to the east of Madagascar.
On March 22 the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard NASA’s Terra satellite provided a visible image of Joaninha soon after it developed. Born as Tropical Depression 22S, it quickly intensified into a tropical storm and was renamed Joaninha. Convective (rising air that consolidates into clouds and storms) bands of thunderstorms spiraled into the center of circulation from the north and east. The center of circulation was obscured by high clouds.
At 11 a.m. EDT on March 22, 2019, maximum sustained winds near Joaninha’s center were near 46 mph (40 knots/74 kph). Joaninha was centered near 15.0 degrees south latitude and 62.4 degrees east longitude. That’s about 760 nautical miles southwest of Diego Garcia in the Central Indian Ocean. Diego García is an atoll, located just south of the equator.
Joaninha is forecast to move south, later southeast, while continuing to intensify. The Joint Typhoon Warning Center or JTWC expects Joaninha’s sustained winds to peak at 115 mph (100 knots /185 kph). The storm is forecast to pass far to the east of Mauritius and La Reunion Island. After four days, at the tropical cyclone will start to weaken as conditions deteriorate.
Tropical Cyclone Veronica continued to move toward Australia’s Pilbara Coast in Western Australia. NASA-NOAA’s Suomi NPP satellite provided visible and infrared images of the storm that indicated heavy rainfall.
The Australian Bureau of Meteorology, or ABM updated warnings on March 22. The Warning zone extends from Wallal Downs to Mardie including Port Hedland, Karratha and Barrow Island.
The Watch zone extends to the inland Pilbara to include Pannawonica, Marble Bar and Nullagine.
Suomi NPP passed over Savannah on March 22 and the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument provided visible and infrared images of the storm. William Straka III, who created some of the images noted “As you would expect, the infrared channel on VIIRS showed large amounts of tropospheric gravity waves and overshooting [cloud] tops associated with the intense convection. In another image Veronica was illuminated by the full moon.”
Shortly after the Suomi NPP satellite passed over the storm, the GCOM-W1 satellite also flew over Severe Tropical Cyclone Veronica. “The Advanced Microwave Scanning Radiometer or AMSR2 instrument aboard GCOM-W1 showed a completely enclosed eye as well as the convection around the circulation,” Straka said. The microwave instruments provide critical information that is not seen by the infrared or visible imagery for forecasters.
As of 9:02 a.m. EDT (9:02 p.m. AWST local time) on March 22, Severe Tropical Cyclone Veronica was a category 4 storm on the Australian scale. Veronica had sustained winds of 175 kilometers per hour. It was centered near 17.9 degrees south latitude and 116.9 degrees east longitude about 315 kilometers north of Karratha.
ABM noted “Severe Tropical Cyclone Veronica, a Category 4 system, is moving slowly southwards towards the Pilbara coast. During Saturday it is expected to take a more southeast track and reach the coast late Saturday or Sunday. A severe coastal impact is likely.”
For updated forecasts, visit ABM: http://www.bom.gov.au/
March 22, 2019 – Tropical Cyclone Trevor Fills Australia’s Gulf of Carpentaria in NASA Image
Visible imagery from NASA’s Aqua satellite showed Tropical Cyclone Trevor filling up Australia’s Gulf of Carpentaria.
The Gulf of Carpentaria is a large, shallow sea. It is surrounded on three sides by northern Australia and bounded by the Arafura Sea to the north.
Trevor had crossed the Cape York Peninsula on March 21 and moved into the Gulf. On On March 22 the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard NASA’s Aqua satellite provided a visible image of Trevor. Satellite imagery revealed that Trevor’s clouds had filled up the Gulf. It showed that bands of thunderstorms circled more tightly around the center of circulation than the previous day.
The Australian Bureau of Meteorology or ABM updated warnings and watches on March 22, 2019. The Warning Zone includes Alyangula in the Northern Territory to Burketown in Queensland, and inland parts of the eastern Carpentaria District and the northwest Gulf Country, including Groote Eylandt, Mornington Island, Borroloola, Robinson River, Wollogorang, McArthur River, Cape Crawford, Creswell Downs, Brunette Downs and Doomadgee. The Watch Zone includes inland parts of the northwest Gulf Country in Queensland and the western Carpentaria and central Barkly Districts in the Northern Territory.
At 8 a.m. EDT (9:30 p.m. Australian Central Standard Time or ACST) on March 22, 2019, maximum sustained winds near Trevor’s center were near 90 miles (150 kilometers) per hour. Trevor was centered near 15.0 degrees south latitude and 138.9 degrees east longitude. That’s about 110 miles (185 kilometers) north or Mornington Island.
ABM noted “Dangerous conditions are expected tonight along the southern Gulf of Carpentaria coast as Severe Tropical Cyclone Trevor approaches. The cyclone is expected to cross the coast during Saturday morning, March 23, between Port McArthur and the Northern Territory/Queensland border.”
Destructive winds, very heavy rainfall and storm surge are expected with this storm. ABM said “Coastal residents between Port Roper and the NT/Queensland Border are specifically warned of a very dangerous storm tide as the cyclone center approaches the coast. Tides will rise significantly above the normal high tide, with damaging waves and very dangerous flooding during Friday night and Saturday. As the cyclone approaches the coast, a storm tide is also expected between the Northern Territory/Queensland border and Burketown. Large waves may produce minor flooding along the foreshore.”
Mar. 21, 2019 – NASA Sees Tropical Cyclone Trevor Move Into Gulf of Carpentaria
Tropical Cyclone Trevor has crossed Queensland, Australia’s Cape York Peninsula and re-emerged into the Gulf of Carpentaria. Visible imagery from NASA’s Terra satellite confirmed the movement back over water.
Tropical Cyclone Trevor is expected to intensify in the Gulf of Carpentaria. A severe impact on the southwestern Gulf of Carpentaria coast is likely over the weekend, according to the Australian Bureau of Meteorology or ABM.
On March 21 the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard NASA’s Terra satellite provided a visible image of Trevor. Trevor hadn’t strengthened enough over water yet to develop an eye in visible imagery, but the center was surrounded by powerful thunderstorms. Microwave satellite imagery suggests that an eye has re-developed.
ABM updated warnings and watches on March 21, 2019. The Warning zone stretches from Cape Shield in the Northern Territory to Burketown in Queensland, including Borroloola, Groote Eylandt and Mornington Island, and Kowanyama to Aurukun. Watch Zone goes from Burketown to Karumba.
At 11 a.m. EDT on March 21, (12:30 a.m. AWST Australian Eastern Standard Time on March 22), maximum sustained winds near Trevor’s center were near 68 miles (110 kilometers) per hour. Trevor was a strong tropical storm. Trevor was located near 13.9 degrees South latitude and 140.6 degrees East longitude, about be 84 miles (135 kilometers) west southwest of Aurukun and 283 miles (455 kilometers) east of Alyangula. Tropical Cyclone Trevor is located over water in the eastern Gulf of Carpentaria.
ABM forecasts that “Tropical Cyclone Trevor will intensify further as it adopts a more general southwest movement across the Gulf of Carpentaria tonight and during Friday. It is likely to cross the Northern Territory coast during Saturday as a category 4 severe tropical cyclone.” Trevor is expected to make landfall near Borroloola.
Mar. 21, 2019 – Tropical Cyclone Savannah Dissipating in Suomi NPP Satellite Imagery
Tropical Cyclone Savannah appeared as a wispy area of low pressure on imagery from NASA-NOAA’s Suomi NPP satellite.
Suomi NPP passed over Savannah on March 21, 2019 and the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument provided a visible image of the storm as wind shear continued to tear it apart. The VIIRS image showed wispy clouds around the center of circulation, and the bulk of clouds pushed off far from the center to the southeast. That’s because of strong vertical wind shear from the northwest of the storm.
In general, wind shear is a measure of how the speed and direction of winds change with altitude. Tropical cyclones are like rotating cylinders of winds. Each level needs to be stacked on top each other vertically in order for the storm to maintain strength or intensify. Wind shear occurs when winds at different levels of the atmosphere push against the rotating cylinder of winds, weakening the rotation by pushing it apart at different levels.
The wind shear affecting Savannah has been strong for the last couple of days.
The Joint Typhoon Warning Center (JTWC) provided the final warning on the system at 5 a.m. EDT (0900 UTC) when it was located 1,026 nautical miles southeast of Diego Garcia near
19.8 degrees south latitude and 84.3 degrees east longitude. Savannah’s maximum sustained winds had dropped to 35 knots (40 mph).
Savannah is expected to dissipate later in the day on March 21.
Mar. 21, 2019 – NASA Sees Tropical Cyclone Veronica Affecting Australia’s Pilbara Coast
Visible imagery from NASA’s Terra satellite showed Tropical Cyclone Veronica skirting the Pilbara coast of Western Australia.
On March 21 the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard NASA’s Terra satellite provided a visible image of Veronica. Veronica had a 10 nautical mile wide pinhole eye surrounded by powerful thunderstorms. Bands of thunderstorms spiraled into the center of circulation from the northwest and east. Veronica’s southeastern quadrant was spreading clouds along the Pilbara coastline of northern Western Australia.
The Australian Bureau of Meteorology or ABM updated warnings and watches on March 21, 2019. The Warning zone stretches from Pardoo to Mardie including Port Hedland, Karratha and Barrow Island. The Watch zone stretches from Pardoo to Wallal Downs, Mardie to Onslow and extending to the inland Pilbara to include Pannawonica, Tom Price and Marble Bar.
At 8:48 a.m. EDT (8:48 p.m. AWST Australian Western Standard Time) on March 21, 2019, maximum sustained winds near Veronica’s center were near 121 miles (195 kilometers) per hour. Veronica was centered near 17.3 degrees south latitude and 117.3 degrees east longitude. That’s about 223 miles (360 kilometers) north-northwest of Port Hedland and 239 miles (385 kilometers) north of Karratha.
AMB noted in that advisory, “Severe Tropical Cyclone Veronica, a Category 4 system, is moving slowly towards the Pilbara coast. The cyclone should continue its south to southwest track tonight and Friday before taking a more south southeast track on Saturday. Whilst it is possible that the cyclone may weaken before reaching the Pilbara coast, a severe coastal impact is likely.”
ABM forecasts Veronica to move in a southerly direction and make landfall on March 24, near Whim Creek. Whim Creek is located between Port Hedland to the northeast and Exmouth to the southwest.
Mar. 20, 2019 – NASA’s Terra Satellite Eyes a Weaker Tropical Cyclone Savannah
Tropical Cyclone Savannah visibly showed the effects of wind shear in imagery from NASA’s Terra satellite.
On March 20, 2019 at 12:55 a.m. EDT (0455 UTC) the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard NASA’s Terra satellite captured a visible image of the storm that revealed the bulk of clouds and showers were pushed southeast of the center from strong vertical wind shear. That wind shear was at a rate of 25 to 40 knots. Although most of the clouds were pushed away from the center, a ghostly ring of clouds still circled the circulation center.
At 11 a.m. EDT (1500 UTC) on March 20, 2019, maximum sustained winds near Savannah’s center were near 40 knots (46 mph/74 kph). Savannah was centered near 19.1 degrees south latitude and 83.3 degrees east longitude. That’s about 964 nautical miles (1,109 miles/1785 kilometers) southeast of Diego Garcia. Diego García is an atoll just south of the equator in the central Indian Ocean. Savannah was slowly tracking to the west.
The Joint Typhoon Warning Center forecasts Savannah to track west-southwestward over the next 36 hours while gradually dissipating under the persistent influence of strong vertical wind shear.
Mar. 20, 2019 – NASA’s Aqua Satellite Sees Tropical Cyclone Veronica Develop Off Western Australia’s Coast
NASA’s Aqua satellite provided a view of Tropical Cyclone Veronica after it developed off the northern coast of Western Australia.
On March 20, 2019 the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard NASA’s Aqua satellite captured a visible image of the storm that revealed bands of thunderstorms spiraling into the center of circulation. The Joint Typhoon Warning Center noted that the system continued to consolidate as rain bands wrapped tighter toward a pinhole formative eye. When Aqua passed over Veronica, the storm’s southeastern quadrant was brushing the Dampier Peninsula. That peninsula is located north of Broome and Roebuck Bay in Western Australia and bordered by the Indian Ocean to the west and north and King Sound to the east.
Although there are not yet any warnings in place, the Australian Bureau of Meteorology or ABM has posted a watch area from Pardoo to Mardie, including Port Hedland and Karratha, Western Australia. A Blue Alert is in effect for people in or near communities between Mardie and Pardoo, including Port Hedland, South Hedland, Wickham, Roebourne, Point Samson, Karratha and Dampier. ABM recommends those residents to prepare for cyclonic weather and organize an emergency kit including first aid kit, torch, portable radio, spare batteries, food and water.
At 8:47 a.m. EDT (8:47 p.m. AWST Australia local time) on March 20, 2019, maximum sustained winds near Veronica’s center were near 75 miles (120 kilometers) per hour, making it a Category 1 hurricane on the Saffir-Simpson Hurricane Wind Scale. Trevor was centered near 15.8 degrees south latitude and 118.0 degrees east longitude. That’s about 314 miles (505 kilometers) north of Port Hedland. ABM noted “The cyclone is expected to continue tracking west southwest tonight and during Thursday, March 21. On Friday, March 22, the system will intensify further as it adopts a more southerly track, towards the Pilbara coast.”
ABM forecasts that Veronica will turn to the south and head toward Karratha by March 23. Residents along the Pilbara coast should prepare for Veronica.