July 13, 2020 – NASA Finds Cristina Devoid of Rainfall, Now a Remnant Low
NASA’s Terra Satellite found there were no areas of heavy rainfall in former tropical storm Cristina. The storm is now a remnant low-pressure area.
On July 13 at 02:25 a.m. EDT (0625 UTC), the MODIS instrument that flies aboard NASA’s Terra satellite provided an infrared image of Cristina. The image revealed Cristina was devoid of rainfall and was just a swirl of low to mid-level clouds. The highest clouds were located in the northeastern quadrant, but were also devoid of rainfall. Credit: NASA/NRL
The National Hurricane Center (NHC) reported at 11 p.m. EDT on July 12 (0300 UTC, July 13), the center of Post-Tropical Cyclone Cristina was located near latitude 20.7 degrees north and longitude 126.5 degrees west. Cristina is centered about 1075 miles (1,730 km) west of the southern tip of Baja California Mexico. Cristina is moving toward the west near 12 mph (19 kph) and this motion is expected to continue for the next two or three days. Maximum sustained winds are near 35 mph (55 kph) with higher gusts. The estimated minimum central pressure is 1007 millibars.
On July 13 at 02:25 a.m. EDT (0625 UTC), the Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard NASA’s Terra satellite provided an infrared image of Cristina. The image revealed Cristina was devoid of rainfall and was just a swirl of low to mid-level clouds. The highest clouds were located in the northeastern quadrant, but were also devoid of rainfall.
Cristina had degenerated to a remnant low-pressure area because the circulation was devoid of deep convection and strong thunderstorms. Gradual weakening is anticipated and the remnant low will likely dissipate in a few days.
Hurricanes/tropical cyclones 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.
July 12, 2020 – NASA’s Aqua Satellite Finds a Small Area of Strength Left in Cristina
Tropical Storm Cristina was barely holding onto tropical storm status on Sunday, July 12, 2020, as infrared imagery from NASA’s Aqua satellite revealed only one area of strong storms remaining.
On July 12 at 6:05 a.m. EDT (1005 UTC) the MODIS instrument that flies aboard NASA’s Aqua satellite showed a small area of strong storms in Tropical Storm Cristina east of the center of circulation where cloud top temperatures were as cold as minus 50 degrees Fahrenheit (in dark blue) (minus 45.5 Celsius). Credit: NASA/NRL
The National Hurricane Center expects Cristina to weaken to a remnant low-pressure area in the next day.
Infrared data provides temperature information, and the strongest thunderstorms that reach high into the atmosphere have the coldest cloud top temperatures. NASA uses instruments aboard various satellites to provide infrared, microwave and visible data. Those data help forecasters determine if a storm is intensifying or weakening.
On July 12 at 6:05 a.m. EDT (1005 UTC) the Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard Aqua showed a small area of strong storms in Tropical Storm Cristina east of the center of circulation where cloud top temperatures were as cold as minus 50 degrees Fahrenheit (minus 45.5 degrees Celsius).
At 4 a.m. EDT (0900 UTC) on July 12, the center of Tropical Storm Cristina was located near latitude 20.7 degrees north and longitude 123.3 degrees west. That is about 870 miles (1,405 km) west of the southern tip of Baja California, Mexico. The National Hurricane Center (NHC) said that Cristina is moving toward the west near 13 mph (20 kph), and this motion is expected to continue for the next few days. Maximum sustained winds have decreased to near 45 mph (75 kph) with higher gusts. The estimated minimum central pressure is 1002 millibars.
NHC Hurricane Forecaster Eric Blake noted in the 4 a.m. EDT discussion, “Conventional satellite and scatterometer data indicate that Cristina has weakened during the past several hours. Deep convection [strong rising air that forms the thunderstorms that make up a tropical cyclone] has become fragmented near the center of the cyclone, with only a small amount in the eastern semicircle.
Cristina should gradually lose strength during the next few days due to a combination of very cool waters and increasing [wind] shear, along with nearby dry air. These factors will likely cause the storm to transition into a non-convective remnant low on Monday.”
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July 11, 2020 – NASA Finds Cristina Still on the Cusp of Hurricane Status
Tropical Storm Cristina continues to move west through the Eastern Pacific Ocean and has been struggling to become a hurricane, but because it is tracking over cool waters. So becoming a hurricane may not happen. Infrared satellite imagery revealed Cristina is also somewhat lopsided with the bulk of clouds and storms on its south and eastern sides.
On July 11 at 5:20 a.m. EDT (0920 UTC) the MODIS instrument that flies aboard NASA’s Aqua satellite showed a very small area of strongest storms in Tropical Storm Cristina around the center of circulation where cloud top temperatures were as cold as minus 70 degrees Fahrenheit (in red) (minus 56.6 Celsius). Strong storms with slightly warmer temperatures surrounded the rest of the storm. Credit: NASA/NRL
At 11 p.m. EDT on July 10, satellite data indicated an eye-like feature developing in Cristina that disappeared by the morning hours of July 11. Cristina is struggling to intensify further because it is moving over cool sea surface temperatures. NASA’s Aqua satellite provided a look at the cloud top and sea surface temperatures around Cristina.
The National Hurricane Center noted that despite being over relatively cool 24 degrees Celsius (75.2 degrees Fahrenheit) waters, Cristina is maintaining its strength for now. Tropical cyclones require sea surface temperatures of at least 26.6 degrees Celsius (80 degrees Fahrenheit) to maintain strength.
Infrared data provides temperature information, and the strongest thunderstorms that reach high into the atmosphere have the coldest cloud top temperatures.
On July 11 at 5:20 a.m. EDT (0920 UTC) the Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard Aqua showed a very small area of the strongest storms in Tropical Storm Cristina around the center of circulation where cloud top temperatures were as cold as minus 70 degrees Fahrenheit (minus 56.6 Celsius). Strong storms with slightly warmer temperatures surrounded the rest of the storm. Deep convection wraps most of the way around the center and is strongest on the south side of the circulation.
At 5 a.m. EDT (0900 UTC), the center of Tropical Storm Cristina was located near latitude 20.4 north and longitude 118.3 west. That is about 565 miles (910 km) west-southwest of the southern tip of Baja California, Mexico. Cristina is moving toward the west-northwest near 16 mph (26 kph) and this motion is expected into early next week. Maximum sustained winds are near 70 mph (110 kph) with higher gusts. Weakening of the storm is forecast to begin soon and Cristina is expected to become a post-tropical cyclone early next week.
July 10, 2020 – NASA Infrared Data Shows Cristina Strengthening
NASA’s Aqua satellite revealed better organization and colder cloud top temperatures in Tropical Storm Cristina, indications that the storm was strengthening.
On July 10 at 4:35 a.m. EDT (0835 UTC), the MODIS instrument aboard NASA’s Aqua satellite gathered temperature information about Tropical Storm Cristina’s cloud tops. MODIS found a small area of powerful thunderstorms (red) where temperatures were as cold as or colder than minus 70 degrees Fahrenheit (minus 56.6 Celsius). Credit: NASA/NRL
On July 10 at 4:35 a.m. EDT (0835 UTC), the MODIS instrument aboard NASA’s Aqua satellite analyzed Tropical Storm Cristina’s cloud tops in infrared light. Infrared data provides temperature information, and the strongest thunderstorms that reach high into the atmosphere have the coldest cloud top temperatures.
The Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard NASA’s Aqua satellite found that the most powerful thunderstorms were east and south of the center of circulation, where temperatures were as cold as or colder than minus 70 degrees Fahrenheit (minus 56.6 Celsius). These cloud top temperatures had become colder than they were over the previous day. Cloud top temperatures that cold indicate strong storms with the potential to generate heavy rainfall.
The National Hurricane Center noted, “Cristina has become better organized during the past several hours. A curved band wraps almost completely around the center, and a ragged eye has occasionally been apparent in satellite images.”
At 5 a.m. EDT (0900 UTC) on July 10, the center of Tropical Storm Cristina was located near latitude 18.8 degrees north and longitude 113.0 degrees west. Cristina is far from land and about 345 miles (560 km) southwest of the southern tip of Baja California. Cristina was moving toward the west-northwest near 12 mph (19 kph) and this general motion with a gradual bend to the west is expected during the next few days. The estimated minimum central pressure was 993 millibars.
Maximum sustained winds are near 70 mph (110 kph) with higher gusts. The National Hurricane Center indicated that Cristina could become a hurricane later today; however, a weakening trend should begin by tonight.
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.
July 09, 2020 – NASA Sees Storms Wrapping Around Tropical Cyclone Cristina
The analysis of Tropical Cyclone Cristina’s cloud top temperatures revealed some bands of thunderstorms were developing and wrapping around the center of the storm’s circulation.
On June 8 at 4:20 p.m. EDT (2020 UTC) NASA’s Aqua satellite analyzed Tropical Storm Cristina using the Atmospheric Infrared Sounder or AIRS instrument. AIRS found coldest cloud top temperatures as cold as or colder than (purple) minus 63 degrees Fahrenheit (minus 53 degrees Celsius). Credit: NASA JPL/Heidar Thrastarson
Banding thunderstorms are generally an indication that a tropical cyclone is getting more organized.
How Tropical Cyclones Form
Tropical cyclones are like giant engines that use warm, moist air as fuel. The warm, moist air over the ocean rises upward from near the surface. As the warm air rises, it causes an area of lower air pressure near the surface. Air from surrounding areas with higher air pressure pushes in to the low-pressure area. Then that “new” air becomes warm and moist and rises, too. As the warm air continues to rise, the surrounding air swirls in to take its place. As the warmed, moist air rises and cools off, the water in the air forms clouds. The whole system of clouds and wind spins and grows, fed by the ocean’s heat and water evaporating from the surface.
NASA Uses Infrared Light to Analyze Storms
One of the ways NASA researches tropical cyclones is by using infrared data that provides temperature information. Cloud top temperatures provide information to forecasters about where the strongest storms are located within a tropical cyclone (which are made of hundreds of thunderstorms).
Tropical cyclones do not always have uniform strength. Some quadrants of a tropical cyclone contain more powerful thunderstorms than other quadrants. Temperature data indicates where those strongest storms are located. The stronger the storms, the higher they extend into the troposphere, and the colder the cloud temperatures.
On June 8 at 4:20 p.m. EDT (2020 UTC) NASA’s Aqua satellite analyzed the storm using the Atmospheric Infrared Sounder or AIRS instrument. AIRS found 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.
Those cold temperatures were found around the center and in a developing band of thunderstorms northeast of the center. Satellite data showed the center was located underneath the northeastern side of the main area of convection due to moderate vertical wind shear. The AIRS image also showed banding features were developing across the northern portion of the circulation. One band of thunderstorms northeast of center brought rainfall to part of the coast of southwestern Mexico.
Cristina’s Status on July 9, 2020
Overnight from July 8 to July 9 although deep convection and strong thunderstorm development had been increasing, the overall cloud pattern and structure of the storm changed little and it continued to lack banding features.
At 5 a.m. EDT (0900 UTC) on July 9, the center of Tropical Storm Cristina was located near latitude 16.8 degrees north and longitude degrees 109.4 west. That is about 370 miles (590 km) west-southwest of Manzanillo Mexico. The estimated minimum central pressure is 995 millibars.
NOAA’s National Hurricane Center (NHC) said Cristina was moving toward the west-northwest near 12 mph (19 kph), and this motion with an increase in forward speed is expected during the next few days. On the forecast track, Cristina will remain well offshore of the coast of Mexico.
Maximum sustained winds were near 65 mph (100 kph) with higher gusts. Some strengthening is forecast and Cristina could become a hurricane by Friday.
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.
The AIRS instrument is one of six instruments flying on board NASA’s Aqua satellite, launched on May 4, 2002.
July 08, 2020 – NASA Analyzes Tropical Cyclone Cristina’s Water Vapor Concentration
When NASA’s Aqua satellite passed over Tropical Storm Cristina in the Eastern Pacific Ocean on July 8, it gathered water vapor data that provided information about the intensity of the storm.
On July 8 at 4:50 a.m. EDT (0850 UTC) NASA’s Aqua satellite passed over Tropical Cyclone Cristina, located in the Eastern Pacific Ocean. Aqua found highest concentrations of water vapor (brown) and coldest cloud top temperatures were around the center. Credits: NASA/NRL
NASA’s Aqua satellite passed over Cristina at 4:50 a.m. EDT (0850 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.
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 the stronger the storms.
The National Hurricane Center noted that satellite images show that the convective organization of Cristina is gradually improving, while bands of thunderstorms are developing across the northern portion of the circulation. The center of Cristina’s circulation was still under the northeastern side of the main area of convection due to moderate vertical wind shear, but that wind shear appears to be diminishing.
On July 8 at 11 a.m. EDT (1500 UTC), the center of Tropical Storm Cristina was located near latitude 14.6 degrees north and longitude 106.9 degrees west. That is about 350 miles (560 km) south-southwest of Manzanillo, Mexico.
Cristina is moving toward the northwest near 12 mph (19 kph). A turn to the west-northwest is expected by tonight, and that motion is expected to continue for the next few days. On the forecast track, the cyclone will remain well offshore the coast of Mexico. The estimated minimum central pressure is 998 millibars.
Maximum sustained winds are near 60 mph (95 kph) with higher gusts. Gradual strengthening is expected over the next couple of days, and Cristina is forecast to become a hurricane on Thursday.
National Hurricane Center forecaster Andrew Latto noted, “The decreasing shear over Cristina combined with warm sea surface temperatures and a moist air mass should allow the cyclone to intensify over the next couple of days.”
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.
July 07, 2020 – NASA Finds Powerful Storm’s Around Tropical Storm Cristina’s Center
A low-pressure area strengthened quickly and became Tropical Storm Cristina in the Eastern Pacific Ocean and infrared imagery from NASA revealed the powerful thunderstorms fueling that intensification.
On July 7 at 4:10 a.m. EDT (0810 UTC) the MODIS instrument that flies aboard NASA’s Aqua satellite revealed two areas of very powerful thunderstorms (yellow) around Cristina’s center where cloud top temperatures were as cold as minus 80 degrees Fahrenheit (minus 62.2 Celsius). Credit: NASA/NRL
Cristina developed by 5 p.m. EDT on Monday, July 6, according to the National Hurricane Center in Miami, Fla. Six hours later it strengthened into a tropical storm and was renamed Cristina.
On July 7 at 4:10 a.m. EDT (0810 UTC), the Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard NASA’s Aqua satellite used infrared light to analyze the strength of storms within Cristina. NASA researches these storms to determine how they rapidly intensify, develop and behave.
Tropical cyclones are made of up hundreds of thunderstorms, and infrared data can show where the strongest storms are located. That is because infrared data provides temperature information, and the strongest thunderstorms that reach highest into the atmosphere have the coldest cloud top temperatures.
MODIS found those strongest storms in two areas around Cristina’s center of circulation where cloud top temperatures were as cold as minus 80 degrees Fahrenheit (minus 62.2 Celsius). NASA research has found that cloud top temperatures that cold indicate strong storms with the potential to generate heavy rainfall.
At 11 a.m. EDT (1500 UTC) on July 7, the National Hurricane Center (NHC) said the center of Tropical Storm Cristina was located near latitude 12.2 degrees north and longitude 102.8 degrees west. Cristina is centered about 480 miles (770 km) south-southeast of Manzanillo, Mexico. The estimated minimum central pressure is 1005 millibars. Maximum sustained winds are near 40 mph (65 kph) with higher gusts.
Cristina was moving toward the west-northwest near 13 mph (20 kph), and the NHC expects that general motion to continue for the next few days, keeping the cyclone well away from the coast of Mexico.
NHC forecaster David Zelinsky noted in the July 7 Discussion, “The [vertical wind] shear and some nearby dry air that appear to have inhibited Cristina’s organization so far are not expected to persist as negative factors for much longer. All of the models still forecast strengthening, and given the very favorable environment that the cyclone will encounter in a day or two, a period of rapid intensification at some point would not be surprising.”
Strengthening is anticipated and Cristina is forecast to become a hurricane in a day or two.
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.
