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Hurricane Season 2011: Hurricane Philippe (Atlantic Ocean)
10.07.11
 
Hurricane Philippe was captured by the MODIS instrument on NASA's Terra satellite at 2:45 p.m. EDT on Oct. 6. › View larger image
This visible image of Hurricane Philippe was captured by the MODIS instrument on NASA's Terra satellite at 2:45 p.m. EDT on Oct. 6, as it was moving north in the Atlantic Ocean.
Credit: NASA Goddard/MODIS Rapid Response Team
NASA Saw Strong Shadow-casting Stormclouds Near Hurricane Philippe's Center

Hurricane Philippe is going to remain at sea over the weekend as it continues to move to the north central Atlantic Ocean. NASA's Terra satellite captured an image of Philippe that showed the power around the storm's center, but that power is being limited as the hurricane moves north.

When NASA's Terra satellite flew over Hurricane Philippe at 2:45 p.m. EDT on Oct. 6, the Moderate Resolution Imaging Spectroradiometer (MODIS) got a close look at the most powerful thunderstorms around the storm's center. MODIS provides a lot of detail in its visible and infrared imagery, and it showed higher, towering thunderstorms around the center of Philippe that were casting shadows on the lower surround cloud tops. Higher cloud tops indicate stronger thunderstorms, and suggest stronger rainfall.

Twenty-four hours makes a big difference in the life of a hurricane. In fact, in 20 hours, Hurricane Philippe is now in cooler waters and is battling stronger southwesterly wind shear - two factors that spell trouble for keeping a hurricane together. Tropical cyclones like Philippe need sea surface temperatures as warm as 80F (26.6C) to at least maintain their strength. The temperatures are dropping below that threshold as Philippe ventures further north in the Atlantic.

Microwave satellite imagery today, Oct. 7, noticed that Philippe's eyewall has begun to deteriorate as result of those factors. The wind shear's effects are noticeable on visible imagery as well, because most of the strongest convection and thunderstorms are being pushed to the northeast of Philippe's center. As a result of wind shear and cooler waters Philippe is now weakening.

At 11 a.m. EDT, Philippe's maximum sustained winds were near 85 mph (140 kmh). He was moving to the east-northeast near 16 mph (26 kmh). The center of the hurricane was 575 miles east-southeast of Bermuda, near 29, 9 North and 55.5 West. It had a minimum central pressure of 980 millibars. Over the weekend, Philippe is expected to turn to the north-northeast and speed up as it moves to the central North Atlantic. Philippe will remain in the open waters of the Atlantic. By Sunday, the National Hurricane Center expects Philippe to become extra-tropical.

Text credit: Rob Gutro
NASA/Goddard Space Flight Center, Greenbelt, Md.



October 6, 2011

A 3-D rendering of TRMM precipitation radar data on October 5 at 1:52 p.m. EDT showed deep convective towers › View larger image
A 3-D rendering of TRMM precipitation radar data on October 5 at 1:52 p.m. EDT showed deep convective towers (towering thunderstorms) reached to heights of over 13km (~8 miles).
Credit: NASA/SSAI, Hal Pierce
NASA's TRMM satellite flew over Philippe on Oct. 6 at 00:24 UTC. Philippe's rainfall was mostly moderate. › View larger image
NASA's TRMM satellite flew over Philippe on Oct. 6 at 00:24 UTC. Philippe's rainfall was mostly moderate. The yellow and green areas indicate moderate rainfall between .78 to 1.57 inches per hour. Red areas are considered heavy rainfall at almost 2 inches (50 mm) per hour.
Credit: SSAI/NASA, Hal Pierce
A 3-D Look at Philippe Provided Clues of Transition into a Hurricane

Tropical Storm Philippe took its time to strengthen into a hurricane because of wind shear problems. The wind shear lessened, and Philippe became a hurricane today, after 12 days of moving across the Atlantic Ocean. NASA's TRMM satellite saw towering thunderstorms and intense rainfall within Philippe yesterday, which provided forecasters with a clue that the storm was strengthening. Philippe reached hurricane status this morning, Oct. 6, 2011.

Over two days, the Tropical Rainfall Measuring Mission (TRMM) satellite provided forecasters with cloud heights and rainfall rates occurring within Tropical Storm Philippe. TRMM is managed by both NASA and the Japanese Space Agency, JAXA.

The National Hurricane Center (NHC) upgraded Philippe to a hurricane at 1500 UTC (11 a.m. EDT) on Thursday, October 6 2011. Earlier TRMM Microwave Imager (TMI) data from October 6, 2011 at 0024 UTC (Oct. 5 at 8:24 p.m. EDT) showed that tropical storm Philippe's center of circulation had become better defined and an eyewall was forming. Microwave satellite imagery also shows an eye-like feature, while the visible imagery from NOAA's GOES satellite hints at the indication of an eye, although mostly covered with clouds.

On Oct. 6, Philippe's maximum sustained winds were near 80 mph (130 kmh). Philippe is a Category One hurricane on the Saffir-Simpson scale, but some weakening is forecast in the next two days. Philippe is located about 425 miles (680 km) southeast of Bermuda, near 27.8 North and 60.0 West. The hurricane is moving to the north-northeast near 9 mph (15 kmh) and is expected to move toward the northeast and speed up.

The TRMM satellite also had an excellent look at Philippe earlier on Wednesday, October 5, 2011 at 1752 UTC (1:52 p.m. EDT). TRMM's Precipitation Radar (PR) scanned directly over Philippe and revealed that Philippe had bands of intense rainfall that around the southeast side of the center of circulation.

A 3-D rendering of that TRMM PR data showed deep convective towers reached to heights of over 13km (~8 miles). Previous research from NASA scientists show that whenever these "hot towers" are spotted within a tropical cyclone, the storm typically intensifies within six hours, and Philippe became a hurricane today.

Text credit: Hal Pierce/Rob Gutro
SSAI/NASA/Goddard Space Flight Center, Greenbelt, Md.



October 5, 2011

This TRMM image shows the heaviest rainfall in Philippe (2 inches/50 mm per hour) in red. › View larger image
This TRMM image shows the heaviest rainfall in Philippe (2 inches/50 mm per hour) in red, falling in its southeastern quadrant. Moderate to light rainfall appears in green and blue, falling at a rate between .78 to 1.57 inches (20 to 40 mm) per hour.
Credit: NASA/SSAI, Hal Pierce
NASA Sees Wind Shear and Heavy Rainfall in Tropical Storm Philippe

Heavy rainfall was occurring in Tropical Storm Philippe's southeastern quadrant when NASA's Tropical Rainfall Measuring Mission (TRMM) satellite flew over it this week, and the storm continues to strengthen.

Philippe was still a tropical storm when the TRMM satellite passed above on October 3, 2011 at 1806 UTC (2:06 p.m. EDT) but the National Hurricane Center (NHC) predicts that the storm may become a hurricane in a couple days. TRMM's TMI and Precipitation Radar (PR) data showed that bands of powerful convective thunderstorms were still dropping rain at a rate of over 50mm/hr (~2 inches) in the southeastern quadrant of the storm because wind shear was pushing it there.

Philippe has been battling wind shear from the northwest, as the coldest cloud tops, heaviest rain and frequent lightning have remained on the southeastern side of the storm for the last two days.

At 11 a.m. EDT on Oct. 4, Tropical Storm Philippe's maximum sustained winds were still near 65 mph (as they were when TRMM flew overhead on Oct. 3). However, the National Hurricane Center noted that Philippe may still strengthen and reach hurricane status in the next couple of days. Philippe is still a small storm, about 170 miles in diameter, as tropical storm-force winds extend out 85 miles from the center.

Philippe's center was about 530 miles (850 km) south-southeast of Bermuda, near latitude 25.3 north and longitude 61.3 west. Philippe is moving toward the northwest near 6 mph (9 kmh), but is expected to speed up and turn to the northeast on Thursday, Oct. 6 because of a strong mid-latitude trough approaching it.

Text credit: Rob Gutro
NASA/Goddard Space Flight Center, Greenbelt, Md.



October 4, 2011

This TRMM image shows heaviest rainfall in the northern quadrant of Philippe (2 inches/50 mm per hour) in red. › View larger image
This TRMM image shows heaviest rainfall in the northern quadrant of Philippe (2 inches/50 mm per hour) in red. Moderate to light rainfall appears in green and blue, falling at a rate between .78 to 1.57 inches (20 to 40 mm) per hour.
Credit: NASA/SSAI, Hal Pierce
TRMM's PR was used in the image on the right to show a vertical cross section (slice) through one of these thunderstorms. › View larger image
TRMM's PR was used in the image on the right to show a vertical cross section (slice) through one of these thunderstorms. The image showed that one of these tall thunderstorm towers reached to heights above 17 km (~10.5 miles).
Credit: NASA/SSAI, Hal Pierce
TRMM Satellite Sees Powerful Hot Tower in Tropical Storm Philippe

Tropical Storm Philippe, located in the central Atlantic Ocean, showed signs of strengthening on Oct 2. NASA's Tropical Rainfall Measuring Mission (TRMM) satellite obtained data when it passed over on October 2, 2011 at 1902 UTC ( 3:02 PM EDT). TRMM's Microwave Imager (TMI) and Precipitation Radar (PR) derived rainfall showed that Philippe had powerful thunderstorms in the north-central part of the storm dropping rainfall at a rate over 50 mm/hr (~2 inches).

TRMM's PR was used to create a 3-D image that showed a vertical cross section (slice) through one of these thunderstorms. The image showed that one of these tall thunderstorm towers reached to heights above 17 km (~10.5 miles). Deep convective towers like this can be an indication of future intensification especially when they are located near the core of the storm.

At 11 a.m. EDT on Oct. 4, the National Hurricane Center placed the center of Tropical Storm Philippe near latitude 23.9 north and longitude 59.4 west. Philippe was moving toward the west near 12 mph (19 kmh) but it is forecast and is expected to slow and turn northwest then northward. PhiIippe's maximum sustained winds are near 65 mph (100 kmh). Philippe is expected to strengthen to hurricane-force and then swing to the northeast and head away from Bermuda.

Text credit: Rob Gutro
NASA/Goddard Space Flight Center, Greenbelt, Md.















September 30, 2011

Ophelia and Philippe › View larger image
This visible image from the GOES-13 satellite on Sept. 30 at 7:45 a.m. EDT Hurricane Ophelia on a track to the Northern Atlantic and Tropical Storm Philippe westbound for the Caribbean. Hilary is now a depression in the eastern Pacific.
Credit: NASA/NOAA GOES Project
GOES-13 Satellite Sees Ophelia and Philippe Keeping Atlantic Active, Hilary Fading in Pacific

A Tropical Storm watch is in effect in Bermuda today as Hurricane Ophelia is expected to pass east of the island this weekend, while Philippe continues heading to the Caribbean. A visible image from the GOES-13 satellite showed how Ophelia is much more organized than Philippe. Hilary is even less organized in the eastern Pacific.

NOAA's GOES-13 satellite captured the image at 7:45 a.m. EDT on Sept. 30, that showed the three tropical cyclones on both sides of the U.S. The image was created at NASA's GOES Project at NASA Goddard Space Flight Center, Greenbelt, Md.

On Sept. 30, Ophelia's maximum sustained winds had rocketed up to 115 mph. She was located about 620 nautical miles south-southeast of Bermuda and moving to the north-northwest at 12 mph. Minimum central pressure was 960 millibars. A turn to the north with an increase in forward speed is expected later today, and the core of Ophelia is expected to pass east of Bermuda on Saturday.

Philippe's winds did increase to 50 mph overnight from Sept. 29 to 30th. He was 1145 miles east-northeast of the leeward islands and moving northwest near 13 mph. Minimum central pressure was 1004 millibars. This weekend, Philippe is expected to turn toward the west-northwest and slow down. Overnight, Philippe's center dissipated and re-formed further to the north.

In the eastern Pacific, Hilary weakened to a tropical depression with maximum sustained winds near 35 mph. The center was near 23.0N and 121.5W, about 740 miles west of the southern tip of Baja California. She's moving to the north-northwest near 7 mph, and is expected to dissipate over the weekend.

Text credit: Rob Gutro
NASA/Goddard Space Flight Center, Greenbelt, Md.



September 29, 2011

GOES-13 captured Ophelia (left) and Philippe (right) in one image on Sept. 29, 2011 at 10:45 a.m. EDT. › View larger image
NOAA's GOES-13 satellite captured both Ophelia (left) and Philippe (right) in one image of the Atlantic Ocean basin on Sept. 29, 2011 at 10:45 a.m. EDT.
Credit: NASA/NOAA GOES Project
GOES-13 Satellite Sees Ophelia Stronger, Philippe Maintaining Strength

Tropical Storm Ophelia is strengthening and moving north in the Atlantic, while Tropical Storm Philippe is holding tight and moving toward the Caribbean.

NOAA's GOES-13 satellite captured both Ophelia and Philippe as Ophelia approaches hurricane strength, while Philippe maintains tropical storm strength. NASA's GOES Project, housed at NASA Goddard Space Flight Center in Greenbelt, Md. takes the data from the GOES-13 satellite and creates images and animations from it. The NASA GOES Project created what is called a "full-disk" view of the Atlantic that provided a visible look at the different structures of each storm.

Tropical Storm Ophelia has taken on the signature comma-shape on GOES-13 imagery. A comma-shaped storm indicates a well-formed storm. Philippe, however, appears as a rounded area of clouds on the GOES-13 visible image.

Both infrared and visible data from the Atmospheric Infrared Sounder (AIRS) instrument on NASA's Aqua satellite show that Ophelia's clouds have become more organized today as it strengthens. Yesterday, the tropical storm appeared somewhat elongated and today it is very symmetric.

At 11 a.m. EDT, Tropical Storm Ophelia had maximum sustained winds near 70 mph (110 kmh), and she's expected to become a hurricane later today. The center of tropical storm Ophelia was near latitude 20.9 north, and longitude 61.8 west. That's about 205 miles (330 km) north-northeast of the Northern Leeward Islands. Ophelia is moving toward the north-northwest near 9 mph (15 kmh) and she's forecast to turn north later today, according to the National Hurricane Center.

By end of the weekend, Ophelia is expected to be post-tropical in the northern Atlantic Ocean and bring rains to eastern Newfoundland, Canada.

At 11 a.m. EDT on Sept. 29, Philippe's maximum sustained winds were near 45 mph (75 kmh) and little change in strength is expected. The center of Tropical Storm Philippe was located near latitude 18.6 north and longitude 42.6 west. Phippe is centered about 1240 miles (1995 km) west of the Cape Verde Islands. He's moving to the west near 13 mph (20 kmh) and is expected to continue in that direction through Friday and then turn west-northwest.

As Ophelia heads north, Tropical Storm Philippe is taking a more westerly route toward the Caribbean, but unlike his "sister" Ophelia, Philippe is forecast to weaken.

Text credit: Rob Gutro
NASA/Goddard Space Flight Center, Greenbelt, Md.



September 28, 2011

GOES-13 captured both Ophelia (left) and Philippe (right) in one image today, Sept. 28, 2011. › View larger image
NOAA's GOES-13 satellite captured both Ophelia (left) and Philippe (right) in one image of the Atlantic Ocean basin today, Sept. 28, 2011.
Credit: NASA/NOAA GOES Project
Tropical Storms Ophelia and Philippe Trying to be Different

Satellites now have two tropical storms to follow in the Atlantic, as Tropical Storm Ophelia has been reborn east of the Northern Leeward Islands. Tropical Storms Ophelia and Phillipe differ in size, strength and direction.

NOAA's GOES-13 satellite captured both Ophelia and Philippe in one image of the Atlantic Ocean basin today, Sept. 28, 2011. NASA's GOES Project, housed at NASA Goddard Space Flight Center in Greenbelt, Md. takes the data from the GOES-13 satellite and creates images and animations from it. The NASA GOES Project created what is called a "full-disk" view of the Atlantic that showed some differences in the storms.

At 11 a.m. EDT on Sept. 28, the center of Tropical Storm Ophelia was near latitude 18.7 north and longitude 59.9 west. That's about 215 miles (340 km) east of the Northern Leeward Islands. Ophelia is moving toward the north-northwest near 3 mph (6 kmh) and is expected to speed up over the next two days. Ophelia's maximum sustained winds are now near 50 mph and she is expected to strengthen according to the National Hurricane Center. Ophelia is about 170 miles in diameter as tropical-storm-force winds extend out 140 miles from the center, although mainly to the east. Satellite data shows a curved band of thunderstorms around Ophelia's eastern side, where the strongest winds rage. The reason the strongest thunderstorms and winds are in the eastern quadrant is because Ophelia is battling wind shear from the west.

While Ophelia is taking a more northerly track through the Atlantic, Philippe is now taking a more westerly track. Tropical Storm Philippe appears to be twice as large as Ophelia, as tropical storm-force winds extend out 175 miles from the center, making him about 350 miles in diameter. At 11 a.m. EDT on Sept. 28, Tropical Storm Philippe's maximum sustained winds were near 40 mph, and appear to be weakening, unlike his "sister" Ophelia who is gaining strength. Philippe is located about 980 miles (1580 km) west of the Cape Verde Islands near 16.4 North and 38.8 West and moving to the west-northwest at 12 mph (19 kmh). Satellite imagery shows that Philippe's low-level center is exposed.

Ophelia is slow moving and slowly intensifying. Ophelia is expected to become a hurricane by the weekend on its trek north. Philippe, however, is battling strong wind shear and that's pushing convection to the northern edge of circulation and is not expected to strengthen.

Text credit: Rob Gutro
NASA/Goddard Space Flight Center, Greenbelt, Md.



September 27, 2011

Infrared image of Tropical Storm Philippe from AIRS taken on Sept. 27 at 0347 UTC. › View larger image
This infrared image shows Tropical Storm Philippe's coldest clouds (purple) and strongest thunderstorms where cloud temperatures were colder than -63F. It was captured from the AIRS instrument on NASA's Aqua satellite on Sept. 27 at 0347 UTC. Philippe is a compact storm.
Credit: NASA/JPL, Ed Olsen
Tropical Storm Philippe captured by MODIS on Sept. 26 at 11:40 a.m. EDT. › View larger image
This visible image of Tropical Storm Philippe was captured by the MODIS instrument on NASA's Aqua satellite on Sept. 26 at 11:40 a.m. EDT. The brighter white clouds in the center are higher clouds and stronger thunderstorms. Philippe is in the eastern Atlantic Ocean and no threat to land.
Credit: NASA Goddard MODIS Rapid Response Team
Compact Tropical Storm Philippe Has Some Strength Around Its Center

Temperatures of -63 Fahrenheit are what NASA's Aqua satellite measured in the cloud tops that surround the center of compact Tropical Storm Philippe.

Very cold temperatures in NASA infrared satellite imagery of tropical cyclones tell meteorologists that cloud tops are high, and the thunderstorms they're associated with have a lot of punch.

When NASA's Aqua satellite flew over Philippe on Sept. 27 at 0347 UTC (11:47 p.m. EDT, Sept. 26) the Atmospheric Infrared Sounder instrument took an infrared snapshot of the storm. Infrared data shows temperatures, and the coldest temperatures and strongest thunderstorms (and heaviest rainfall) was located around Philippe's center.

At 5 a.m. EDT on Sept. 27, Philippe had maximum sustained winds near 50 mph (85 kmh). Tropical storm-force winds extended 85 miles from the center, making Philippe about 170 miles in diameter. The center of tropical storm Philippe was near latitude 16.1 north and longitude 35.1 west in the open waters of the eastern Atlantic. Philippe is moving toward the northwest near 7 mph (11 kmh) and this general Motion is expected to continue through tomorrow. The National Hurricane Center doesn't expect any strengthening over the next 24 hours.

Text credit: Rob Gutro
NASA/Goddard Space Flight Center, Greenbelt, Md.


















September 26, 2011

This GOES-13 satellite image from Sept. 26 Ophelia east of the Leeward Islands and Philippe in the far eastern Atlantic. › View larger image
This GOES-13 satellite image from Sept. 26 at 1445 UTC (10:45 a.m. EDT) shows the remnants of Tropical Storm Ophelia east of the Leeward Islands, and Tropical Storm Philippe in the far eastern Atlantic. Hurricane Hilary can also be seen off the west coast of Mexico, in the eastern Pacific Ocean.
Credit: NASA/NOAA GOES Project
This AIRS infrared image shows the concentrated area of strongest storms (purple) south of Philippe's center of circulation. › View larger image
This infrared image from the AIRS instrument on NASA's Aqua satellite shows the concentrated area of strongest storms (purple) south of Philippe's center of circulation. AIRS captured this image on Sept. 25 at midnight EDT. Cloud tops in the purple area are as cold as -63 Fahrenheit, and suggest heavy rainfall.
Credit: NASA/JPL, Ed Olsen
Satellite Sees Ophelia Fade, Phillip Frolick Far Away

The two tropical disturbances in the Atlantic Ocean today don't pose any concern for land areas, as Ophelia weakened to a remnant low east of the Leeward Islands, and Tropical Storm Philippe is in the far eastern Atlantic where he'll stay. Both were captured on one incredible image by the GOES-13 satellite today.

Tropical Storm Ophelia posed a threat to the Leeward Islands, but weakened to a remnant low pressure area late Sunday, Sept. 25. At 5 p.m. EDT yesterday, satellites showed a small, weak circulation center in Ophelia. Most of the strongest convection and thunderstorms were still being pushed to the east of the storm's center as a result of strong wind shear. When a storm is not stacked on top of itself, it cannot strengthen. Think of a tropical storm like a stack of tires. If it's stacked, it can remain balanced. If the top tires lean to one side, the stack starts to fall. Wind shear makes the top of tropical cyclones lean, so it can't circulate from bottom to top, and it begins to weaken. Ophelia weakened to a remnant low pressure area late yesterday.

Today, Sept. 26, Ophelia's remnants on visible imagery from NOAA's GOES-13 satellite appears as a large, disorganized area of thunderstorms. It's centered a couple of hundred miles east of the Northern Leeward Islands. Those same strong upper-level winds that pushed the strongest thunderstorms and showers away from Ophelia's center are still happening, and preventing it from organizing. The National Hurricane Center gives Ophelia's remnants a 20% chance of redeveloping in the next 48 hours.

The GOES-13 satellite image that showed Ophelia's disorganization also showed Philippe frolicking in the eastern Atlantic. The GOES-13 satellite image was taken on Sept. 26 at 10:45 a.m. EDT and created by the NASA GOES Project at NASA's Goddard Space Flight Center in Greenbelt, Md.

Tropical Storm Philippe formed on Saturday, Sept. 24 as the seventeenth tropical depression of the Atlantic Ocean hurricane season. It only took twelve hours for the depression to strengthen into a tropical storm, and it was named Philippe at 5 p.m. EDT that same day.

At 11 a.m. EDT on Sept. 26, Philippe was about 680 miles (1095 km) west of the Cape Verde Islands, near 15.2 North and 34.2 West. He had maximum sustained winds near 60 mph and was moving to the northwest near 12 mph (19 kmh). Philippe's minimum central pressure is 997 millibars.

Infrared satellite imagery from the Atmospheric Infrared Sounder instrument aboard NASA's Aqua satellite has noticed that the strongest convection has appeared to come and go. The National Hurricane Center noted that despite the pulsing convection, Philippe hasn't really changed. Infrared data shows the strongest storms over the southern quadrant of the storm.

Philippe is expected to continue moving to the northeast over the next couple of days, in open ocean.

Text credit: Rob Gutro
NASA/Goddard Space Flight Center, Greenbelt, Md.