Tag: Gonzalo 2020

July 26, 2020 – NASA Imagery Catches Tropical Storm Gonzalo Degenerating into a Tropical Wave

After Tropical Storm Gonzalo passed over Trinidad and Tobago, it weakened to a remnant low pressure area. NASA-NOAA’s Suomi NPP satellite passed overhead from space and snapped a visible image that revealed the storm was transitioning into a tropical wave.

The Republic of Trinidad and Tobago is a dual island nation and the southernmost island country in the Caribbean. Trinidad Island is about 7 miles (11 km) off the northeastern coast of Venezuela.

NASA-NOAA Satellite Imagery Reveals No Circulation Center

The Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard Suomi NPP provided a visible image of the Gonzalo on July 25 after it passed Trinidad and Tobago. Satellite data showed that it was opening up into a tropical wave. By 5 p.m. EDT, satellite data showed that Gonzalo’s structure had degraded. By that time there was no clear evidence of a well-defined center in visible imagery. It appeared that the system has opened into a tropical wave. A tropical wave is an elongated area of low pressure that stretches from north to south.

Gonzalo Going, Going…

The final advisory on Gonzalo was issued at 5 p.m. EDT on July 25 after it passed Trinidad and Tobago and weakened to a remnant low-pressure area. At 5 p.m. EDT (2100 UTC), the remnants of Gonzalo were located near latitude 11.0 degrees north and longitude 63.0 degrees west. That was about 125 miles (195 km) west-northwest of Trinidad. Maximum sustained winds are near 35 mph (55 kph) with higher gusts.

On Sunday, July 26, the remnants of Gonzalo were classified as a tropical wave currently over the eastern Caribbean. Tropical squalls associated with the remnants of Gonzalo will continue to move westward for the next couple of days.

For more than five decades, NASA has used the vantage point of space to understand and explore our home planet, improve lives and safeguard our future. NASA brings together technology, science, and unique global Earth observations to provide societal benefits and strengthen our nation. Advancing knowledge of our home planet contributes directly to America’s leadership in space and scientific exploration.

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

By Rob Gutro 
NASA’s Goddard Space Flight Center

July 25, 2020 – NASA Sees a Poorly Organized Tropical Storm Gonzalo Nearing Trinidad and Tobago

Tropical Storm Gonzalo was approaching the southern Windward Islands when NASA-NOAA’s Suomi NPP satellite passed overhead from space and snapped a visible image of the storm. On July 25, 2020, heavy rain from Gonzalo was nearing Trinidad and Tobago and warnings were posted.

The Republic of Trinidad and Tobago is a dual island nation and the southernmost island country in the Caribbean. Trinidad Island is about 7 miles (11 km) off the northeastern coast of Venezuela.

NASA-NOAA Satellite Imagery Shows Poor Organization

The Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard Suomi NPP provided a visible image of the Gonzalo on July 24 as it was nearing Trinidad and Tobago, and the southern Windward Islands. Gonzalo appeared poorly organized. Even at 11 p.m. EDT on July 24, although there was an increase in deep convection in association with Gonzalo, data from an Air Force Reserve Hurricane Hunter aircraft continued to show that the tropical cyclone is poorly organized. That did not improve on July 25 as the surface circulation was still poorly defined, and barely closed. That means that little change in intensity is forecast as the cyclone approaches the southern Windward Islands during the afternoon hours on July 25.

Tropical Storm Warning in Effect on July 25

A Tropical Storm Warning is in effect for Tobago, Grenada and its dependencies. Interests elsewhere in the Windward Islands should monitor the progress of this system.

Status of Gonzalo on Saturday, July 25, 2020

At 8 a.m. EDT (1200 UTC), NOAA’s National Hurricane Center or NHC noted the center of Tropical Storm Gonzalo was located near latitude 10.3 degrees north and longitude 59.8 degrees west. That is about 100 miles (165 km) east of Trinidad.

Gonzalo is moving toward the west near 18 mph (30 kph). A general westward to west-northwestward motion is expected for the next couple of days. Maximum sustained winds are near 40 mph (65 kph) with higher gusts. The estimated minimum central pressure is 1009 millibars.

Gonzalo’s Forecast Track

Little change in strength is forecast before Gonzalo reaches the southern Windward Islands later today.  On the forecast track, Gonzalo will move across the southern Windward Islands this afternoon or evening and over the southeastern Caribbean Sea on Sunday, July 26. Weakening is expected after Gonzalo moves over the southeastern Caribbean Sea, and the system is forecast to dissipate by Sunday night or Monday.

For more than five decades, NASA has used the vantage point of space to understand and explore our home planet, improve lives and safeguard our future. NASA brings together technology, science, and unique global Earth observations to provide societal benefits and strengthen our nation. Advancing knowledge of our home planet contributes directly to America’s leadership in space and scientific exploration.

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

For past NASA updates on Gonzalo visit: https://blogs.nasa.gov/hurricanes/tag/gonzalo-2020/

July 24, 2020 – NASA Water Vapor Data Reveals Tropical Storm Gonzalo’s Soaking Capability

When NASA’s Aqua satellite passed over the North Atlantic Ocean, it gathered water vapor data on Tropical Storm Gonzalo as tropical storm warnings, a tropical storm watch, and hurricane watch were posted.

Water vapor analysis of tropical cyclones tells forecasters how much potential a storm has to develop. 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 stronger the storms.

NASA’s Aqua satellite passed over Tropical Storm Gonzalo on July 24 at 1:35 a.m. EDT (0535 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 were around the center of circulation.

MODIS data also showed coldest cloud top temperatures were as cold as or colder than minus 70 degrees Fahrenheit (minus 56.6 degrees Celsius) in those storms. Storms with cloud top temperatures that cold have the capability to produce heavy rainfall.

The National Hurricane Center (NHC) noted that Gonzalo is expected to produce total rain accumulations of 2 to 5 inches, with isolated maximum amounts of 7 inches in Barbados and the Windward Islands tonight (July 24) through Sunday night (July 26). Gonzalo is also expected to produce total rain accumulations of 1 to 2 inches in Trinidad and Tobago. Rainfall in Barbados and the Windward Islands could lead to life-threatening flash floods.

On July 24, a Tropical Storm Warning is in effect for St. Lucia, Barbados, St. Vincent and the Grenadines. A Hurricane Watch is in effect for Barbados, St. Vincent and the Grenadines and a Tropical Storm Watch is in effect for Tobago, Grenada and its dependencies.

At 8 a.m. EDT (1200 UTC), NHC said satellite data indicated that the center of Tropical Storm Gonzalo was located near latitude 10.0 degrees north and longitude 52.8 degrees west. Gonzalo is moving toward the west near 15 mph (24 kph). A westward to west-northwestward motion with an increase in forward speed is expected through the weekend. The estimated minimum central pressure is 1000 millibars. Maximum sustained winds are near 60 mph (95 kph) with higher gusts. Gonzalo is a small tropical cyclone.  Tropical-storm-force winds extend outward up to 25 miles (35 km) from the center. Some strengthening is forecast during the next day or two, and there is still a chance that Gonzalo could become a hurricane before reaching the Windward Islands. On the forecast track, the center of Gonzalo will approach the southern Windward Islands tonight and then move across the islands on Saturday (July 25) and over the eastern Caribbean Sea on Sunday (July 26).

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

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

July 23, 2020 – NASA Examines Tropical Storm Gonzalo’s Structural Changes

Visible and microwave imagery from NASA’s Aqua satellite indicated Tropical Storm Gonzalo was slightly less organized than it was on the previous day.

Gonzalo formed in the central North Atlantic Ocean on July 21 and is moving west.

The Moderate Imaging Spectroradiometer or MODIS instrument that flies aboard NASA’s Aqua satellite captured a visible image of Gonzalo late on July 22. The image was created by NASA Worldview at NASA’s Goddard Space Flight Center in Greenbelt, Md. The July 22 visible image of Gonzalo showed a central dense overcast that had become a bit ragged. The banding of thunderstorms seen in earlier images had dissipated.

Microwave imagery captured at 12:53 a.m. EDT (0452 UTC) on July 23 from the Atmospheric Infrared Sounder or AIRS instrument also aboard Aqua, indicated a small convective ring (rising air that forms the thunderstorms that make up a tropical cyclone) was present under the overcast. At 11 a.m. EDT, the National Hurricane Center noted, “Recently-obtained microwave data from overnight shows that Gonzalo’s center is a little farther south than previously estimated.”

On July 23, NHC forecaster Robbie Berg noted, “The storm’s structure has become a little disheveled since yesterday, with the deep convection losing some organization.”

Hurricane Watch in Effect

On July 23, the National Hurricane Center (NHC) issued a Hurricane Watch for Barbados and St. Vincent and the Grenadines.

Gonzalo’s Status on July 23

The National Hurricane Center (NHC) said at 11 a.m. EDT (1500 UTC), the center of Tropical Storm Gonzalo was located near latitude 9.6 degrees north and longitude 48.3 degrees west.  That is about 885 miles (1,425 km) east of the Southern Windward Islands Gonzalo is moving toward the west near 14 mph (22 kph). A westward to west-northwestward motion with an increase in forward speed is expected through the weekend.

Maximum sustained winds are near 65 mph (100 kph) with higher gusts. Gonzalo is a small storm, and tropical-storm-force winds extend outward up to 35 miles (55 km) from the center. The estimated minimum central pressure is 997 millibars.

NHC provided two key messages about the storm:

1. There is an increasing risk of wind and rain impacts from Gonzalo in portions of the southern Windward Islands this weekend; however, there is significant uncertainty in how strong Gonzalo will be when it moves across the islands.

2. Despite the uncertainty in Gonzalo’s future intensity, hurricane conditions are possible across portions of the southern Windward Islands. Hurricane Watches are currently in effect for Barbados and St. Vincent and the Grenadines, and additional watches for other islands could be required later today. Interests in the southern Windward Islands should monitor the progress of Gonzalo and follow any advice given by local officials.

NHC said, “Some strengthening is forecast during the next couple of days, and Gonzalo could become a hurricane tonight or on Friday. On the forecast track, the center of Gonzalo will approach the southern Windward Islands Friday night and move across the islands Saturday and Saturday evening.”

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

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

July 22, 2020 – NASA Sees Record-Breaking New Tropical Storm Gonzalo Strengthening

The seventh named tropical cyclone of the North Atlantic Ocean has formed, and like some others this season, it has broken a record. NASA’s Aqua satellite provided a look at the small record-breaker.

The National Hurricane Center (NHC) reports that Gonzalo is the earliest seventh named storm on record in the Atlantic basin, beating Gert of 2005 by 2 days. Tropical Depression Seven formed on July 21 by 5 p.m. EDT in the Central North Atlantic Ocean, and by 8:50 a.m. EDT on July 22 it strengthened into a tropical storm and was renamed Gonzalo.

One of the ways NASA researches tropical cyclones is using infrared data that provides temperature information. The AIRS instrument aboard NASA’s Aqua satellite captured a look at those temperatures in Gonzalo and gave insight into the size of the storm and its rainfall potential.

Cloud top temperatures provide information to forecasters about where the strongest storms are located within a tropical cyclone. Tropical cyclones do not always have uniform strength, and some sides have stronger sides than others. The stronger the storms, the higher they extend into the troposphere, and the colder the cloud temperatures. NASA provides that data to forecasters at NOAA’s National Hurricane Center or NHC so they can incorporate it in their forecasting.

On July 22 at 12:11 a.m. EDT (0411 UTC) NASA’s Aqua satellite analyzed the storm using the Atmospheric Infrared Sounder or AIRS instrument. AIRS found coldest cloud top temperatures as cold as or colder than minus 63 degrees Fahrenheit (minus 53 degrees Celsius). NASA research has shown that cloud top temperatures that cold indicate strong storms that have the capability to create heavy rain.

By 11 a.m. EDT, the NHC noted, “Satellite imagery indicates that the cyclone has become significantly better organized since the last advisory.  Visible imagery shows a well-defined central dense overcast with a hint of an eye and an outer convective band in the western semicircle, while a microwave overpass showed a well-defined inner convective ring feature.”

At 11 a.m. EDT (1500 UTC), NHC reported the center of Tropical Storm Gonzalo was located near latitude 9.9 degrees north and longitude 43.6 degrees west. That is about 1,205 miles (1,935 km) east of the southern Windward Islands. Gonzalo is moving toward the west near 14 mph (22 kph). A general westward motion at a faster forward speed is expected during the next few days. The estimated minimum central pressure is 1000 millibars.

Maximum sustained winds have increased to near 50 mph (85 kph) with higher gusts. Gonzalo is a small tropical cyclone, as tropical-storm-force winds extend outward only up to 25 miles (35 km) from the center. Additional strengthening is forecast during the next couple of days, and Gonzalo is expected to become a hurricane by Thursday, July 23.

Interests in the southern Windward Islands should monitor the progress of this system.

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

For more than five decades, NASA has used the vantage point of space to understand and explore our home planet, improve lives and safeguard our future. NASA brings together technology, science, and unique global Earth observations to provide societal benefits and strengthen our nation. Advancing knowledge of our home planet contributes directly to America’s leadership in space and scientific exploration.

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

By Rob Gutro
NASA’s Goddard Space Flight Center