Tara (Eastern Pacific Ocean) 2018

Oct. 17, 2018 – NASA Catches the Scattered Remains of Former Tropical Storm Tara

NASA’s Aqua satellite captured an infrared image of the remnants of former Tropical Storm Tara after it dissipated near the coast of western Mexico’s Jalisco state.  Jalisco is a western Mexican state along the Eastern Pacific Ocean.

Aqua image of Tara
At 1:05 a.m. EDT (0505 UTC) on Oct. 17 NASA’s Aqua satellite gathered infrared data on the remnants of Tara. Infrared data provides temperature information. Strongest thunderstorms were found along the coast just south of Puerto Vallarta and scattered throughout Jalisco state. Those fragmented storms had cloud top temperatures as cold as (yellow) minus 63 degrees Fahrenheit (minus 53 Celsius). Credit: NASA/NRL

On Oct. 16 the high terrain of Mexico caused Tara’s surface circulation to open into a trough or elongated area of low pressure and dissipate.

At 11 p.m. EDT on Oct. 16 (0300 UTC on Oct 17) the National Hurricane Center or NHC noted the remnants of Tara were located near latitude 20.0 degrees north and longitude 105.5 degrees west. That’s 105 miles (170 km) northwest of Manzanillo, Mexico. Maximum sustained winds were near 35 mph (55 kph) and waning.

At that time, NHC’s discussion stated “The remnants of Tara are expected to produce additional rainfall of 1 to 3 inches over the Mexican states of Colima and western Jalisco, through tonight, with isolated maximum storm total amounts of 15 inches possible. These rains may produce life-threatening flash floods and mudslides, especially in mountainous terrain.”

At 1:05 a.m. EDT (0505 UTC) on Oct. 17, the MODIS instrument that flies aboard NASA’s Aqua satellite gathered infrared data on the remnants of Tara. Infrared data provides temperature information. Strongest thunderstorms were found along western Mexico’s coast just south of Puerto Vallarta and scattered throughout Jalisco state. Those fragmented storms had 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.

By Rob Gutro
NASA’s Goddard Space Flight Center

Tara (Eastern Pacific Ocean) 2018

Oct. 16, 2018 – Tropical Storm Tara’s Water Vapor Concentrations Seen by NASA’s Aqua Satellite

When NASA’s Aqua satellite passed over the Eastern Pacific Ocean on Oct. 16 the MODIS instrument aboard analyzed water vapor within Tropical Storm Tara.

Aqua image of Tara
NASA’s Aqua satellite passed over Tropical Storm Tara in the Eastern Pacific Ocean on Oct. 16 at 4:45 a.m. EDT (0845 UTC). The MODIS instrument showed highest concentrations of water vapor (brown) and coldest cloud top temperatures were around the center (over water) and north of the center over western Mexico. Credits: NASA/NRL

On Oct. 16, a Tropical Storm Warning is in effect from Manzanillo to Cabo Corrientes, Mexico and a Tropical Storm Watch is in effect from east of Manzanillo to Punta San Telmo, Mexico.

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 Aqua satellite passed over Tropical Storm Tara on Oct. 16 at 4:45 a.m. EDT (0845 UTC) and the Moderate Resolution Imaging Spectroradiometer or MODIS instrument 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 in areas over mainland Mexico to the north-northeast including the coast.

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. After Aqua passed by, locally heavy rainfall continued along the immediate coastal areas of western Mexico.

The National Hurricane Center or NHC said at 11 a.m. EDT (1500 UTC), the center of Tropical Storm Tara was located near latitude 18.6 degrees north and longitude 104.5 degrees west.

Tara is drifting toward the north-northwest near 1 mph (2 kph). A very slow northwestward motion is expected during the next day or so. Maximum sustained winds have decreased to near 45 mph (75 kph) with higher gusts.

On NHC’s forecast track, the center of Tara should pass very close to the coast of southwestern Mexico, or possibly move inland, today or Wednesday, Oct. 13. Gradual weakening is forecast as Tara’s circulation interacts with the mountains of southwestern Mexico, and the system is forecast to degenerate into a remnant low by Wednesday evening.

NHC forecaster Stewart noted in the 11 a.m. Discussion, “Regardless of the exact track or intensity of Tara or its remnants, heavy rainfall will continue to be a threat along the immediate coast of southwestern Mexico due to the system’s slow motion, and life-threatening flash flooding will be possible in mountainous areas.”

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

By Rob Gutro
NASA’s Goddard Space Flight Center

Tara (Eastern Pacific Ocean) 2018

Oct. 15, 2018 – NASA Finds Tropical Storm Tara Affecting Western Mexico

NASA-NOAA’s Suomi NPP satellite found newly developed Tropical Storm Tara affecting the western coast of Mexico.

Suomi NPP image of Tara
NASA-NOAA’s Suomi NPP satellite passed over Tropical Storm Tara on Oct. 15 and the VIIRS instrument provided a visible image of the storm along the coast of coasts of Mexico’s Michoacan and Jalisco states. Credit: NASA Worldview, Earth Observing System Data and Information System (EOSDIS)

A Tropical Storm Watch is in effect for Punta San Telmo to Cabo Corrientes on Oct. 15.

Tara formed on Oct. 14 around 11 a.m. EDT. It was the twenty second tropical depression of the Eastern Pacific Hurricane Season. Suomi NPP passed over Tara on Oct. 14 and the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument provided a visible image of the storm. The VIIRS image showed the eastern quadrant of the storm over the coasts of Mexico’s Michoacan and Jalisco states.

At 11 a.m. EDT (1500 UTC), the National Hurricane Center or NHC noted that the center of Tropical Storm Tara was located near latitude 17.6 degrees north and longitude 104.4 degrees west. That’s just 95 miles (155 km) south of Manzanillo, Mexico. Tara is moving toward the west-northwest near 1 mph (2 kph) and this slow motion is expected to continue for the next day or so. Maximum sustained winds have increased to near 45 mph (75 kph) with higher gusts. Slow strengthening is forecast during the next few days.

NHC said “On the forecast track, the center of Tara is expected to remain near or just offshore of the southwestern coast of Mexico during the next couple of days.”

By Rob Gutro
NASA’s Goddard Space Flight Center