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Hurricane Season 2008: Paloma (Caribbean Sea)
 
Nov. 12, 2008

Paloma's Remnants One of Two Atlantic Areas Forecasters Watching

Satellite image of Paloma Credit: NASA/LAADS, Jesse Allen
> Larger image
The National Hurricane Center in Miami, Fla. noted in their Tropical Weather Outlook that there are two areas in the Atlantic Ocean that have "Low Potential" for development into a tropical cyclone. One area is the remnants of Hurricane Paloma and the other is in the far eastern Atlantic.

A weak area of low pressure is all that's left of the mighty Hurricane Paloma, and on Nov. 12, it was located between Cuba and the Cayman Islands. The remnant low was moving west-northwestward near 10 mph. The Hurricane Center noted that shower activity is limited, and environmental conditions aren't good for re-organizing the system.

When the Moderate Imaging Spectroradiometer (MODIS) instrument on NASA's Aqua satellite captured this image at 2:15 p.m. EST on November 9, Paloma was degrading from a tropical storm to a tropical depression. Only the faintest hint of a powerful storm remains in the loosely swirling clouds over Cuba. According to the National Hurricane Center, the storm officially dissipated on November 10.

The second area in the Atlantic that forecasters are watching is about 900 miles southwest of the Azores. The Azores is a Portuguese archipelago in the Atlantic Ocean, about 1,500 kilometers (950 miles) from Lisbon, Portugal and about 3,900 km (2,400 miles) from the east coast of North America.

It is there that showers and thunderstorms associated with a slow-moving area of low pressure have diminished today, Nov. 12. This system also has low potential to develop into a tropical cyclone, because the upper-level winds are "becoming increasingly unfavorable," according to the Hurricane Center.

Text credit: Rob Gutro and Holli Riebeek, NASA's Goddard Space Flight Center



Nov. 10, 2008

Cuba Took the Life out of Paloma

Satellite image of Paloma Credit: NASA/JPL
> Larger image
Hurricane Paloma, the Atlantic Ocean's eighth hurricane, made landfall in south central Cuba on Saturday, Nov. 8 around 7 p.m. EST as a category three hurricane on the Saffir-Simpson Scale. That was the beginning of the end for Paloma, as by Monday, Nov. 10, the storm had weakened into a remnant low pressure area.

A couple of things led to Paloma's demise, according to forecasters. It was a combination of strong vertical wind shear (winds that tear a storm apart), the fact that the storm stayed over land for almost a day and was cut-off from the warm waters that power hurricanes, and dry stable air entered into Paloma from an approaching cold front. Paloma's demise is good news for the Bahamas.

Before Paloma met its end, it did reach Category Four hurricane status. On Saturday, Nov. 8 near 4 p.m. EST, Paloma's maximum sustained winds increased for a time to 145 mph. Fortunately, it weakened before making landfall. Around 7 p.m. EST on Saturday, Nov. 8, major hurricane Paloma made landfall just east of Santa Cruz Del Sur, Cuba as a category 3, with maximum sustained winds near 120 mph. It came ashore near 20.8 degrees north latitude and 77.9 degrees east longitude. At that time Paloma's minimum central pressure was 968 millibars.

According to Reuters news service, when Paloma made landfall it downed trees and powerlines, and toppled a communications tower. Reuters reported at 20 foot storm surge that caused flooding along the coast, and actually brought the sea inland by 2,300 feet, flooding hundreds of homes.

By 4 p.m. EST on Sunday, Nov. 9, Paloma weakened to a tropical depression and later weakened into a remnant low. The National Hurricane Center issued its final advisory on Paloma on Monday, Nov. 10 at 0300 UTC (Nov. 9 at 10 p.m. EST). At that time Paloma's remnant low center was located near 22.0 north and 78.0 west moving north near 3 knots (3 mph). Paloma was clinging to life with sustained winds near 25 knots (29 mph) and a minimum central pressure of 1007 millibars.

NASA's Aqua Satellite Instrument Sees Paloma's Colder Clouds

Satellite image of Paloma Credit: NASA/JPL
> Larger image
NASA's Atmospheric Infrared Sounder (AIRS) instrument on NASA's Aqua satellite is working overtime with Hurricane Paloma. AIRS produced infrared and visible images, taken on Nov. 8 at 1:29 p.m. EDT (18:29 UTC) about 6 hours before its center made landfall in Cuba.

The infrared image shows the frigid cloud top temperatures, giving forecasters a clue to the storm's strength. The lowest temperatures (in purple) are associated with Paloma's high, cold cloud tops. Those areas are as cold as 220 degrees Kelvin or minus 63 degrees Fahrenheit (F) or colder. The blue areas are around 240 degrees Kelvin, or minus 27F.

The National Hurricane Center uses cloud temperature as one factor in determining whether a tropical cyclone is strengthening. When cloud temperatures get colder, it means that clouds are getting higher. Building clouds indicate a lot of "uplift" in the atmosphere and stronger thunderstorms.

Satellite image of Paloma Credit: NASA/Jesse Allen, MODIS Rapid Response team > Larger labeled image
> Larger unlabeled image
AIRS' infrared signal doesn't penetrate through clouds, so where there are clear skies AIRS reads the infrared (heat) signal from the ocean and land surfaces, revealing warmer temperatures (colored in orange and red). The orange temperatures are 80F (300 degrees Kelvin) or greater (the darker they are, the warmer they are). Tropical cyclones need sea surface temperatures of 80F to strengthen and maintain their strength.

This image of Paloma was captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite on November 6, 2008. At the time of the image, the storm had a loosely organized appearance, with an obvious pattern of rotation, but no distinct eye. This was captured before Paloma hit the Cayman Islands.

Text credit: Rob Gutro, NASA's Goddard Space Flight Center



Nov. 07, 2008 -- second update

Paloma Strengthens in the Caribbean, Heads for Cuba

Although it's November, Cuba is potentially now facing its a third major hurricane of the season. The island nation was hit hard by Hurricanes Gustav and Ike in a little over a week back in late August and early September. Climatologically, the Atlantic hurricane season is quickly winding down, but Hurricane Paloma is a reminder that the season is not yet over. On average, one storm forms every other year in the Atlantic during the month of November. The favored development region is the central and western Caribbean, which is exactly where Paloma formed. Paloma originated from a persistent area of disturbed weather in the southwestern Caribbean Sea. A tropical depression formed on the afternoon of November 5, 2008 about 170 km (~105 miles) off of the northeast coast of Nicaragua. The following day, with conditions favorable for development, the depression was upgraded to a tropical storm and officially became Paloma as it moved slowly northward. By early that same evening, Paloma had become a hurricane as it entered the northwestern Caribbean.

TRMM image of Paloma from Nov. 7, 2008> Larger image
Credit: Hal Pierce, SSAI/NASA
The Tropical Rainfall Measuring Mission satellite (also known as TRMM) has been in service for over 10 years now and continues to provide valuable images and information on tropical cyclones around the Tropics using a combination of a passive microwave sensor and a first-of-its-kind spaceborne precipitation radar. TRMM captured these images of Hurricane Paloma as it was moving slowly northward through the western Caribbean south of the Cayman Islands. The images were taken at 12:46 UTC (7:46 am EST) November 7. The first image shows the horizontal pattern of rainfall associated with Paloma. Rain rates in the center of the swath come from the TRMM Precipitation Radar (PR) and those in the outer swath from the TRMM Microwave Imager (TMI). The rain rates are overlaid on infrared (IR) data from the TRMM Visible Infrared Scanner (VIRS). TRMM shows that Paloma has a well-organized circulation with a closed eye surrounded by a complete ring of moderate intensity rain (green circular region). A broad area of light to moderate rain (blue and green areas, respectively) extends further out northeast of the center. Another interesting feature is the area of intense rainfall (shown in red) embedded in the eastern eyewall.

3D TRMM image of Paloma from Nov. 7, 2008> Larger image
Credit: Hal Pierce, SSAI/NASA
The second image was taken at the same time and shows a 3D image of the storm courtesy of the TRMM PR. The most prominent feature is a deep convective tower (shown in red), which reaches up to 15 km high. This corresponds with the area of intense rain in the eastern eyewall noted in the previous image. These tall towers are associated with convective bursts and can be a sign of future strengthening as they indicate areas within the storm where heat, known as latent heat, is being released. This heating is what drives the storm's circulation. At the time of these images, Paloma was a category 1 hurricane with sustained winds reported at 70 knots (~81 mph) by the National Hurricane Center (NHC). After these images were taken, Paloma continued to shows signs of intensifying and is expected become a major hurricane or close to it before possibly making landfall along the south-central coast of Cuba.

TRMM is a joint mission between NASA and the Japanese space agency JAXA.

Text credit: Steve Lang/SSAI/Goddard Space Flight Center


Nov. 07, 2008

Hurricane Paloma Hitting Cayman Islands… Cuba Next

TRMM image of Paloma on Nov. 7, 2008> Larger image
Credit: NASA/SSAI, Hal Pierce
On Nov. 7, the Cayman Islands were being hit with winds and rains from Hurricane Paloma and is expected to make landfall in central Cuba early Sunday, Nov. 9, possibly as a major hurricane.

The National Hurricane Center reported that "Paloma is continuing to strengthen this morning with hints of an eye on visible satellite pictures. Further strengthening is likely for the next 24 hours or so before vertical wind shear increases." On Nov. 7 Hurricane Center forecasters are keeping to the forecast that Paloma may become a major hurricane over the weekend. A "Major Hurricane" is a Category 3 or greater hurricane.

On Friday, Nov. 7 at 10 a.m. EST, a hurricane watch is effect for central Cuban provinces, so hurricane conditions are possible within 36 hours. The Central Bahamas also needs to be on guard for hurricane conditions early next week.

NASA's TRMM Satellite Sees Heavy Rainfall Around Paloma's Eye

Hurricane Paloma was seen by the Tropical Rainfall Measuring Mission (TRMM) satellite on Nov. 7 at 433 UTC (11:33 p.m. EST). At the time of this TRMM satellite derived image Paloma had wind speeds of about 65 knots (about 75 mph).

This TRMM image shows the horizontal pattern of rain intensity within the storm. The center is located near the yellow, green and red areas, which indicate rainfall between 20 and 40 millimeters (.78 to 1.57 inches) per hour. The red areas are considered moderate rainfall. "It is evident from this TRMM satellite image that Paloma was becoming a well organized hurricane with very heavy rainfall around a nearly circular eye," said Hal Pierce of NASA Goddard Space Flight Center, Greenbelt, Md. who works with TRMM data. This rainfall analysis of the eye wall used Precipitation Radar (PR) data from the TRMM satellite.

AIRS image of Paloma from Nov. 7, 2008> Larger image Credit: NASA JPL NASA's Aqua Satellite Instrument Sees Paloma's Colder Clouds

NASA's Atmospheric Infrared Sounder (AIRS) instrument on NASA's Aqua satellite is working overtime with Hurricane Paloma. AIRS produced infrared and visible images, taken on Nov. 6 at 1:41 p.m. EDT (18:41 UTC).

The infrared image shows the frigid cloud top temperatures, giving forecasters a clue to the storm's strength. The lowest temperatures (in purple) are associated with Paloma's high, cold cloud tops. Those areas are as cold as 220 degrees Kelvin or minus 63 degrees Fahrenheit (F) or colder. The blue areas are around 240 degrees Kelvin, or minus 27F.

The National Hurricane Center uses cloud temperature as one factor in determining whether a tropical cyclone is strengthening. When cloud temperatures get colder, it means that clouds are getting higher. Building clouds indicate a lot of "uplift" in the atmosphere and stronger thunderstorms.

AIRS' infrared signal doesn't penetrate through clouds, so where there are clear skies AIRS reads the infrared (heat) signal from the ocean and land surfaces, revealing warmer temperatures (colored in orange and red). The orange temperatures are 80F (300 degrees Kelvin) or greater (the darker they are, the warmer they are). Tropical cyclones need sea surface temperatures of 80F to strengthen and maintain their strength.

AIRS visible image of Paloma from Nov. 7, 2008> Larger image Credit: NASA JPL Paloma May Become a Dangerous Category 3 Storm

On Friday, Nov. 7, Paloma strengthened into a Category One hurricane on the Saffir-Simpson Scale with sustained winds near 85 mph. It was still strengthening in the warm waters near the Cayman Islands, and is could become a Category 3 hurricane by Saturday, Nov. 8. before it makes landfall in Cuba.

At 10 a.m. EST Paloma's center was about 75 miles south-southwest of Grand Cayman and about 245 miles west of Montego Bay, Jamaica. That's near latitude 18.3 north and longitude 81.6 west. Paloma is moving toward the north near 7 mph and a gradual turn toward the northeast is expected later in the day or on Nov. 8. The estimated minimum central pressure is 979 millibars.

Caymans and Cuba in for Storm Surge Flooding and Heavy Rainfall

Storm surge flooding of 4 to 6 feet above normal tide levels accompanied by large and dangerous battering waves is expected near the center of Paloma in the Cayman Islands.

The Hurricane Center says that "Paloma is expected to produce total rainfall accumulations of 5 to 10 inches over the Cayman Islands and central and eastern Cuba with isolated maximum totals of 15 inches possible. Flash flooding and mudslides are also possible, especially in higher terrain."

Paloma Nearing Category 2 Storm Strength

AIRS image of Paloma from Nov. 7, 2008, late afternoon> Larger image
Credit: NASA JPL
At 1 p.m. EST on Nov. 7, Paloma's sustained winds increased to 90 mph. It's still a Category one hurricane - just 6 mph shy of a Category 2, and is expected to reach that later today. Paloma was located near 18.4 North and 81.3 West, 60 miles south of Grand Cayman and moving north-northeast near 6 mph. Minimum central pressure is 974 millibars.

The AIRS instrument that flies on NASA's Aqua satellite produced data that helped create this infrared image, taken on Nov. 7 at 1:53 a.m. EDT (6:53 UTC). It shows the frigid temperatures of Paloma's clouds. The lowest temperatures (in purple) are associated with high, cold cloud tops that make up the top of the storm. Those temperatures are as cold as or colder than 220 degrees Kelvin or minus 63 degrees Fahrenheit (F).

For updates on Paloma's strength and forecast tracks, visit: > National Hurricane Center.

Text credit: Hal Pierce/Rob Gutro/SSAI and Goddard Space Flight Center


Nov. 06, 2008 -- second update

Paloma Still Intensifying and Turning Northward Toward Cayman Islands, Cuba

TRMM image of Paloma from November 6, 2008> Larger image
Credit: NASA/SSAI, Hal Pierce
A hurricane watch has been posted for the Cayman Islands. A Hurricane watch means that hurricane conditions are possible within the watch area...generally within 36 hours.

At 1 p.m. EST, Nov. 6, Tropical Storm Paloma, located in the western Caribbean near the Honduras/Nicaragua border, has continued to strengthen. Paloma's maximum sustained winds have increased to near 60 mph with higher gusts. Steady strengthening is forecast during the next couple of days and Paloma could become a hurricane tonight or tomorrow. Paloma was near latitude 15.9 north and longitude 81.9 west or about 105 miles northeast of Cabo Gracias a Dios on the Nicaragua/Honduras border and about 235 miles south of Grand Cayman.

Paloma is moving toward the north near 7 mph...11 km/hr. This general motion is expected today with a gradual turn toward the Northeast forecast late on Friday or on Saturday. Minimum central pressure is now 997 millibars.

The image above shows a rainfall analysis of tropical storm Paloma using data from the Tropical Rainfall Measuring Mission (TRMM) satellite as it passed above on November 6 at 1341 UTC (8:41 AM EST). At that time Paloma was increasing in strength with wind speeds between 35 to 40 knots (40 to 46 miles per hour). Paloma was already a well organized storm with precipitation particularly heavy in a feeder band in Paloma's southwest quadrant. The center of Paloma's circulation was clearly revealed by TRMM's Precipitation Radar (PR) instrument.

TRMM can gauge the rainfall generated by a storm. Paloma is expected to produce total rainfall accumulations of 2 to 4 inches over eastern Honduras and northeastern Nicaragua. Four to eight inches of rain over the Cayman Islands is expected with isolated maximum totals of 12 inches possible.

Tropical Storm Paloma formed in the Caribbean Sea northeast of Nicaragua on the morning of 6 November 2008. Paloma is predicted by the National Hurricane Center to intensify as it moves through the Caribbean and possibly become a category 2 hurricane before hitting central Cuba in the next three or four days.

Text credit: Hal Pierce/Rob Gutro/SSAI and Goddard Space Flight Center


Nov. 06, 2008

Tropical Storm Paloma Forms Quickly in the Caribbean Sea

AIRS image of Tropical Storm Paloma on November 6, 2008> Larger image
Credit: NASA JPL
Twelve hours. That's all it took from the time a tropical depression formed until it grew into a tropical storm in the Caribbean Sea.

At 4 p.m. EST on Wednesday, Nov. 5, tropical depression seventeen was born near latitude 14.0 north and longitude 81.8 west or about 115 miles southeast of Cabo Gracias a Dios on the Nicaragua/Honduras border. By 4 a.m. EST on Thursday, Nov. 6, tropical depression seventeen strengthened into Tropical Storm Paloma.

Paloma is raining on the border of Nicaragua and Honduras today, but the storm is expected to move out into the Caribbean Sea and head toward Cuba.

NASA Frigid Cloud Temperatures an Indicator of Paloma Strengthening

Forecasters are really taking a close look at Paloma, because it strengthened so quickly. Some of the satellite data they're using comes from the Atmospheric Infrared Sounder (AIRS) instrument that flies on NASA's Aqua satellite. The data from AIRS is also used to create an accurate 3-D map of atmospheric temperature, water vapor and clouds, all of which are helpful to forecasters.

The infrared image, taken on Nov. 5 at 2:05 a.m. EDT (7:05 UTC) shows a huge temperature difference between the tops of the clouds in a tropical cyclone and the warm ocean waters that power it. The lowest temperatures (in purple) are associated with high, cold cloud tops that make up the top of the storm. Those temperatures are as cold as or colder than 220 degrees Kelvin or minus 63 degrees Fahrenheit (F). The blue areas are around 240 degrees Kelvin, or minus 27F.

The National Hurricane Center discussion uses cloud temperature as one factor in determining whether a tropical cyclone is strengthening. When cloud temperatures get colder, it means that clouds are getting higher. Building clouds indicate a lot of "uplift" in the atmosphere and stronger thunderstorms. The discussion on Nov. 6 noted "satellite imagery is showing increasing organization...with cloud tops colder than -80 Celsius (minus 112 F) occurring just west of the center. Based on the flight-level winds the depression is upgraded to Tropical Storm Paloma with 35-knot (40 mph) winds."

The infrared signal of the AIRS instrument does not penetrate through clouds. Where there are clear skies AIRS reads the infrared (heat) signal from the ocean and land surfaces, revealing warmer temperatures in orange and red. The orange temperatures are 80F (300 degrees Kelvin) or greater (the darker they are, the warmer they are), and tropical cyclones need sea surface temperatures of 80F to strengthen and maintain their strength.

Paloma Raining on Central America, Headed into the Caribbean Sea

A tropical storm watch remained in effect on Nov. 6 from Puerto Cabezas, Nicaragua northward to Limon, Honduras. A tropical storm watch means that tropical storm conditions are possible within the watch area...in this case within 24-36 hours.

Paloma is expected to produce total rainfall accumulations of 4 to 8 inches over eastern Honduras, northeastern Nicaragua and the Cayman islands with isolated maximum totals of 12 inches possible.

By 7 a.m. on Nov. 6, Paloma was becoming even more organized as it moved slowly north-northwestward near 7 mph. The estimated minimum central pressure is 1000 millibars.

Paloma's maximum sustained winds were near 40 mph and it is expected to strengthen over the next couple of days. Paloma could become a hurricane on Friday, according to National Hurricane Center forecasters.

Paloma's center was near latitude 15.3 north and longitude 82.2 west or about 70 miles east-northeast of the town of Cabo Gracias a Dios on the Nicaragua/Honduras border.

Text credit: Rob Gutro (from NHC reports), NASA's Goddard Space Flight Center