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Hurricane Season 2012: Hurricane Michael (Atlantic Ocean)
09.11.12
 
NASA Infrared Data Reveals Fading Tropical Storm Leslie and Peanut-Shaped Michael

infrared image of Leslie and Michael

When NASA's Aqua satellite passed over the Atlantic it caught Tropical Storm Leslie's clouds over Newfoundland and Tropical Storm Michael to its southwest, resembling a peanut shape. Credit: NASA JPL, Ed Olsen
› Larger image

When NASA's Aqua satellite passed over the Atlantic on Sept. 11 it caught Tropical Storm Leslie's clouds over Newfoundland and peanut-shaped Tropical Storm Michael to its southwest. The Atmospheric Infrared Sounder (AIRS) instrument captured infrared data on Tropical Storms Leslie and Michael when it passed overhead on Sept. 11.

Michael Appears Peanut-Shaped on Satellite Imagery

Tropical Storm Michael forecast to become a remnant low later today, Sept. 11, but as of 11 a.m. EDT Michael still had maximum sustained winds near 45 mph (75 kmh). It was located about 1,090 miles (1,755 km) west of the Azores. Michael is moving to the north-northeast 23 mph (37 kmh) and this motion is expected to continue during the next day or so.

In the AIRS infrared image from around 1 a.m. EDT on Sept. 11, the strongest area of convection (and thunderstorms) appeared to be over Michael's north and eastern quadrants making the storm appear peanut-shaped on NASA satellite imagery. An infrared satellite image of Michael later on Sept. 11 showed that most of the convection has disappeared and Michael appeared as tight swirl of low clouds. Michael is over cool waters and in an environment of strong wind shear, two factors that are weakening the storm quickly. The National Hurricane Center forecast notes that Michael's remnants should then become absorbed by a front in the next day or two.

Tropical Storm Leslie Moving Away from Newfoundland

According to the Canadian Hurricane Centre, Leslie made landfall Tuesday, Sept. 10 in Fortune, Newfoundland, at about 8:30 a.m. AST (7:30 a.m. EDT) with maximum sustained winds near 40 mph (65 kmh). The Seattle Post Intelligencer newspaper reports power outages and flight cancellations. Canadian Broadcasting Corporation news reported heavy rainfall and wind gusts up to 82 mph (132 kmh) over the Avalon Peninsula, including St. John's that caused power outages, and downed trees. Leslie became a post-tropical cyclone as it begins to move away from Newfoundland.

The Canadian Hurricane Center discontinued the hurricane watch for southeastern Newfoundland early on Sept. 11, but a tropical storm warning is in effect for Newfoundland from Indian Harbour to Triton.

AIRS infrared imagery from 1 a.m. EDT on Sept. 11 showed strong thunderstorms around Leslie's center and in bands to the north of the center. At 11 a.m. EDT on Sept. 11, the center of post-tropical cyclone Leslie was located near latitude 49.4 north, longitude 53.6 west, about 130 miles (210 km) north-northwest of St. Johns Newfoundland. The post-tropical cyclone is moving toward the north-northeast at 45 mph (72 kmh).

By 12 p.m. EDT, satellite imagery showed that Leslie is now part of a cold front and is no longer a tropical cyclone. Post-tropical/extratropical cyclone is still producing a large area of tropical-storm-force winds primarily to the north and east of the center as it continues to move north-northeast at 39 knots. This system is forecast to remain a strong Post-tropical cyclone as it moves rapidly toward the northeast and east over the north Atlantic.

Leslie's remnants are expected to skirt southern Iceland on Thursday, Sept. 12 before heading toward Scotland sometime on Sept. 13.

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



Sep. 10, 2012

Visible image of Tropical Storm Leslie and Hurricane Michael taken by MODIS on Sept. 7 at 11:25 a.m. EDT› View larger image
This visible image of Tropical Storm Leslie and Hurricane Michael was taken by the MODIS instrument aboard both NASA's Aqua and Terra satellites on Sept. 7 at 11:25 a.m. EDT.
Credit: NASA Goddard/MODIS Rapid Response Team
Visible image of Tropical Storm Leslie and Hurricane Michael taken by MODIS on Sept. 9 at 12:50 p.m. EDT› View larger image
This visible image of Tropical Storm Leslie and Hurricane Michael was taken by the MODIS instrument aboard both NASA's Aqua and Terra satellites on Sept. 9 at 12:50 p.m. EDT.
Credit: NASA Goddard/MODIS Rapid Response Team
NASA Catches Tropical Storm Leslie and Hurricane Michael in the Atlantic

Satellite images from two NASA satellites were combined to create a full picture of Tropical Storm Leslie and Hurricane Michael spinning in the Atlantic Ocean. Imagery from NASA's Aqua and Terra satellites showed Leslie now past Bermuda and Michael in the north central Atlantic, and Leslie is much larger than the smaller, more powerful Michael.

Images of each storm were taken by the Moderate Resolution Imaging Spectroradiometer, or MODIS instrument that flies onboard both the Aqua and Terra satellites. Both satellites captured images of both storms on Sept. 7 and Sept. 10. The image from Sept. 7 showed a much more compact Michael with a visible eye. By Sept. 10, the eye was no longer visible in Michael and the storm appeared more elongated from south to north.


Leslie Moves Past Bermuda Heads to North Atlantic

On Sept. 8 at 5 p.m. Leslie was a tropical storm with maximum sustained winds near 55 knots. It was about 240 miles (390 km) south-southeast of Bermuda near 29.4 North latitude and 62.5 West longitude. Leslie was moving north and expected to pass to the east of or close to Bermuda later in the day. A tropical storm warning was in force for Bermuda on Sept. 8 and 9, and forecasters at the National Hurricane Center expected rainfall totals of 1 to 2 inches in Bermuda.

By Sept. 9 at 5 p.m. EDT, Leslie had passed to the east of Bermuda and was centered about 175 miles (280 km) east-northeast of the island, near 33.4 North and 61.2 East. Leslie's maximum sustained winds were near 60 mph (95 kmh) as it continued moving to the north at 14 mph (22 kmh).

By Monday, Sept. 10, Leslie had moved north of Bermuda and was about 805 miles (1,300 km) south-southwest of Cape Race, Newfoundland, Canada, near 36.5 North latitude and 60.8 West longitude. Leslie was moving to the north-northeast at 18 mph (30 kmh) and had maximum sustained winds near 60 mph (95 kmh).

MODIS satellite data shows that Leslie has one main band of powerful thunderstorms and heavy rainfall, located to the northeast quadrant of the storm.

Watches have now been posted for Newfoundland, Canada as Leslie tracks northward. A hurricane watch is now in effect in Newfoundland, from Stones Cove to Charlottetown. A hurricane watch means that hurricane conditions are possible within the watch area, in this case within 24 to 36 hours, according to the National Hurricane Center.

In addition, a tropical storm watch is in effect for Newfoundland, from Indian Harbor to Stones Cove and from Fogo Island to Charlottetown.

Monday, Sept. 10 is expected to be Leslie's last day in warm waters and low-wind shear. After today the storm is forecast to move into cooler waters and the wind shear is expected to kick up. Those are two factors that weaken a tropical cyclone. Leslie is expected to start transitioning from a warm core system to a cold core system later on Sept. 10, which means the storm will be undergoing a change into an extra-tropical storm.


Michael, Once "Wide-Eyed," Now Weakening from Atmosphere and Ocean

Hurricane Michael experienced some adjustments in "vision" over the weekend when the storm's eye grew wider. On Sept. 8, Michael was still a hurricane with maximum sustained winds near 90 knots (150 kmh). Michael was located near 33.1 North latitude and 42.3 West longitude, about 925 miles (1,485 km) west-southwest of the Azores. Michael's tropical-storm-force wind field was about 70 miles (110 km) out from the center, making the storm about 140 miles (220 km) in diameter. Michael was weakening slowly due to atmospheric conditions and cooler waters and by Sept. 9, Michael's maximum sustained winds were still near 90 mph (150 kmh) when it was 990 miles (1,590 km) west-southwest of the Azores islands. On Sunday, Michael's eye widened from 10 miles in diameter to 30 miles in diameter, as was seen in satellite imagery.

By Monday, Sept. 10, Michael's maximum sustained winds at 5 a.m. EDT were near 80 mph (130 kmh). Michael was centered about 1,065 miles (1,715 km) west of the Azores Islands near 33.5 North and 45.2 West. Michael was moving to the west at 7 mph (11 kmh) and is expected to turn northwestward later on Sept. 10, followed by a turn to the north and northeast. Michael could become a tropical storm by the end of the day on Sept. 10, according to the National Hurricane Center.


Another Storm Brewing in the Eastern Atlantic

Satellite imagery showed that another tropical depression may be forming in the eastern Atlantic. The low, called System 90L appears more organized on Monday, Sept. 10. It is located about 855 miles west of the Cape Verde Islands and is being carefully watched. The National Hurricane Center gives it a 90 percent chance of becoming a depression later on Sept. 1 as it moves west-northwestward at 15 to 20 mph.

To see the Sept. 10 MODIS image of Leslie and Michael, visit: http://lance-modis.eosdis.nasa.gov/cgi-bin/imagery/single.cgi?image=LeslieMichael.A2012253.1650.4km.jpg

To see the Sept. 7 MODIS image of Leslie and Michael, visit: http://lance-modis.eosdis.nasa.gov/cgi-bin/imagery/single.cgi?image=LeslieMichael.A2012251.1525.4km.jpg

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



Sep. 07, 2012

NASA Keeping an "Eye" on Hurricane Michael

Hurricane Michael's eye was so clear on new satellite imagery from NASA that the surface of the Atlantic Ocean could be seen through it.



MODIS image of Michael› Larger image
This stunning visible image of Hurricane Michael was taken by the MODIS instrument aboard NASA's Aqua satellite on Sept. 6 at 12:20 p.m. EDT. Michael's eye is so clear that the ocean surface is visible through it. Credit: NASA Goddard/MODIS Rapid Response Team
NASA satellites have provided visible, infrared and microwave imagery of Hurricane Michael as it tracks north in the eastern Atlantic. A stunning visible image of Hurricane Michael was taken by the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument that flies aboard NASA's Aqua satellite on Sept. 6 at 12:20 p.m. EDT. In the image, Michael's eye was so clear that the ocean surface is visible through it. Since that time infrared imagery from the Atmospheric Infrared Sounder (AIRS) instrument that also flies aboard Aqua, provided cloud top temperature data. On Sept. 7, cloud top temperatures had cooled around the eye since Sept. 6. The National Hurricane Center noted that the "overall cloud pattern [of the storm] is a little more symmetric than it was 6 hours ago." A recent microwave image taken from the Advanced Microwave Sounding Unit (AMSU) which is also aboard the Aqua satellite showed that the eyewall had widened over the 24 hours from Sept. 6.

At 8 a.m. EDT on Sept. 7, Michael's center was about 920 miles (1,485 km) west-southwest of the Azores islands, near latitude 31.0 north and longitude 40.8 west. Michael's maximum sustained winds were near 105 mph (165 kmh) making it a Category 2 hurricane on the Saffir-Simpson scale. The National Hurricane Center expects Michael to gradually weaken over the next couple of days. Michael was moving toward the north near 3 mph (6 kmh) and the estimated minimum central pressure was 970 millibars.

As Michael has aged, the storm has grown in size. Hurricane force winds extend outward up to 25 miles (35 km) from the center and tropical storm force winds extend outward up to 80 miles (130 km).

The National Hurricane Center (NHC) forecasters analyze the atmosphere to see what will influence the movement of tropical cyclones. In the NHC discussion of Michael on Sept. 7, NHC forecasters noted that the steering flow affecting Michael is weak, which accounts for the storm's slow movement. There are two cut off low pressure areas southwest and southeast of Michael. Over the weekend of Sept. 8 and 9 a ridge (elongated area) of high pressure is expected to strengthen to the north and east of Michael, and a trough (elongated area) of low pressure forming over the western Atlantic are expected to cause Michael to speed up and move to the north-northwest then to the north.

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



Sep. 06, 2012

NASA's TRMM satellite captured data on Michael on Sept. 5, 2012 at 10:59 a.m. EDT. › View larger
NASA's TRMM satellite captured data on Michael on Sept. 5, 2012 at 10:59 a.m. EDT. TRMM saw Michael forming an eye, measured some areas of very heavy rain falling at a rate greater than 3 inches (75 mm) per hour and saw "hot towers" reaching heights of about 9.3 miles (15km). Credit: NASA/SSAI, Hal Pierce
NASA Saw Michael Become an Atlantic Hurricane, Wind Speed More than Doubled

The Atlantic Ocean hurricane season spawned two hurricanes this week and NASA satellites have been monitoring them and providing valuable data to forecasters. NASA's TRMM satellite saw very heavy rainfall and powerful towering thunderstorms in Michael when the storm became a hurricane. Michael's wind speeds more than doubled in 24 hours and it is now a major hurricane on the Saffir-Simpson scale.

Tropical Storm Michael became a hurricane on Sept. 5 and NASA's Tropical Rainfall Measuring Mission (TRMM) satellite passed by and collected data on rainfall and cloud heights. The TRMM satellite had an outstanding daytime view of intensifying tropical storm Michael on Sept. 5, 2012 at 1459 UTC (10:59 a.m. EDT). Michael was located about 1,125 miles (1,815 km) west-southwest of the Azores at that time moving slowly toward the northeast over open waters of the Atlantic. Rainfall was very intense in the forming eye and the TRMM satellite measured some areas of very heavy rain falling at a rate greater than 3 inches (75 mm) per hour.

TRMM's Precipitation Radar instrument showed that towering thunderstorms called "hot towers" within the forming eye wall were reaching heights of about 9.3 miles (15km). "Hot towers" are towering clouds that emit a tremendous amount of latent heat (thus, called "hot"). NASA research indicates that whenever a hot tower is spotted, a tropical cyclone will likely intensify and that's what happened with Michael.

Over the course of 24 hours, Michael's maximum sustained winds had more than doubled. On Sept. 6 at 11 a.m. EDT, Michael had maximum sustained winds were near 115 mph (185 kmh). Just twenty four hours before, Michael's maximum sustained winds were near 50 mph (85 kmh). Michael's center was about 980 miles (1,580 km) west-southwest of the Azores islands, near latitude 28.3 north and longitude 43.3 west. Michael is moving toward the northeast near 7 mph (11 kmh) and is expected to turn northwest by Sept. 8.

The National Hurricane Center noted that Michael is a category three hurricane on the Saffir-Simpson hurricane wind scale and some gradual weakening is expected beginning Friday, Sept. 7 and continuing through the weekend.

In addition to Michael in the Atlantic Ocean basin today, Leslie is moving toward Bermuda over the weekend, and another low pressure area is being watched in the Gulf of Mexico. That other low pressure area, called System 90L, is located near 29.3 North and 88.3 West over the north central Gulf of Mexico. That broad area of low pressure is drifting southward into the Gulf and has a 40% chance of developing into a tropical depression in the next two days.

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



Sep. 05, 2012

AIRS image of Tropical Storm Michael› Larger image
Tropical Storm Michael on Sept. 5 at 0611 UTC (2:11 a.m. EDT) and noticed the strongest thunderstorms and coldest cloud top temperatures (purple) around the center of circulation and in a band of thunderstorms to the northeast of the center. Credit: NASA JPL, Ed Olsen
NASA Imagery Reveals Strength in Tropical Storm Michael's "Arm"

NASA's Aqua satellite shows that tiny Tropical Storm Michael had some strong thunderstorms wrapped around its center and in a band of thunderstorms in its northeastern "arm" or quadrant.

The Atmospheric Infrared Sounder (AIRS) instrument that flies aboard NASA's Aqua satellite captured in infrared image of Tropical Storm Michael on Sept. 5 at 0611 UTC (2:11 a.m. EDT) and noticed the strongest thunderstorms and coldest cloud top temperatures around the center of circulation and in a band of thunderstorms to the northeast of Michael's center. Those cloud top temperatures were as cold as -63 Fahrenheit (-52 Celsius) and indicated strong thunderstorms with heavy rainfall.

On Sept. 5 at 11 a.m. EDT, Michael had maximum sustained winds near 50 mph (85 kmh). The area of tropical storm force winds have expanded over the last two days and now extend outward up to 60 miles (95 km). Michael's center was about 1155 miles (1,855 km) west-southwest of the Azores islands, near latitude 28.3 north and longitude 43.3 west. Michael is moving toward the northeast near 6 mph (9 kmh) and is expected to continue in that direction for the next couple of days.

The National Hurricane Center expects the wind shear that has been battering Michael over the last couple of days to relax, which may allow Michael to become a hurricane by Friday, Sept. 7.

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



Sep. 04, 2012

GOES-13 captured an image of Isaac's huge blanket of clouds over the U.S., and very small Michael in the central Atlantic.› View larger image
NOAA's GOES-13 satellite captured an image of Isaac's huge blanket of clouds over the U.S., large Tropical Storm Leslie headed to Bermuda (Leslie is about 400 miles in diameter), and very small Tropical Storm Michael far to the east of Leslie, and located in the central Atlantic. The larger system north of Leslie is a cold-core, low pressure system.
Credit: NASA GOES Project
Newborn Tropical Storm Michael Struggling Like Leslie and Isaac

Tiny Tropical Storm Michael formed today, Sept. 4, from the thirteenth tropical depression in the Atlantic Ocean, but it seems that wind shear will make Michael struggle to intensify over the next couple of days like his "sister" Tropical Storm Leslie. Isaac's remnants blanket the U.S. east coast.

Leslie has been a tropical storm since late Aug. and has not yet reached hurricane strength because of wind shear, although that is expected to change. Isaac's remnants are also struggling, but struggling to get off the land and back into the Atlantic Ocean. Isaac's remnants are now associated with a stationary frontal system over the U.S. east coast. The storm made landfall in Louisiana as a hurricane on Aug. 29.

NOAA's GOES-13 satellite captured an image of Isaac's huge blanket of clouds over the U.S., large Tropical Storm Leslie headed to Bermuda (Leslie is about 400 miles in diameter), and very small Tropical Storm Michael far to the east of Leslie, and located in the central Atlantic. Michael is more than seven times smaller than Leslie, as tropical-storm force winds only extend out 35 miles (55 km) from the center, making Michael about 70 miles in diameter. The image was created by the NASA GOES Project at NASA Goddard Space Flight Center in Greenbelt, Md.

On Sept. 4 at 11 a.m. EDT, Michael's maximum sustained winds were near 40 mph (65 kmh). Michael was located about 1,220 miles (1,965 km) southwest of the Azores, near latitude 27.0 north and longitude 43.5 west. Michael is moving toward the north-northwest near 5 mph (7 kmh) and expected to move more toward the north in the next couple of days while not strengthening much, according to the National Hurricane Center.

According to NOAA's Hydrometeorological Prediction Center, most of the remnants of Tropical cyclone Isaac are now part of an elongated center of low pressure over the Alabama-Georgia border that is spreading clouds and showers along the U.S. east coast. That center is expected to move south of south-southwest while an upper level low pressure area near Miami moves north-northwestward.

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



Satellite Sees Isaac's Remnants, Tropical Storms Kirk, Leslie and Michael



An animation of satellite observations from Sept. 1-4, 2012, shows Isaac's remnants move from the central to eastern U.S., and tropical storm Leslie nearing Bermuda, Kirk fades in the No. Atlantic on Sept. 2 and tiny Tropical Storm Michael forms on Sept. 4, west of Leslie. This visualization was created by the NASA GOES Project at NASA Goddard Space Flight Center, Greenbelt, Md., using observations from NOAA's GOES-13 satellite. TRT 0:35 Super(s): Courtesy: NASA/NOAA GOES Project Center Contact: Rob Gutro (301) 286-4044