LOADING...
Text Size
Bruce (Southern Indian Ocean)
December 24, 2013

NASA Sees the Last of Cyclone Bruce in Southern Indian Ocean [image-156]

Tropical Cyclone Bruce is winding down in the Southern Indian Ocean as wind shear and cooler waters affect the storm. NASA's Aqua satellite flew over Bruce on December 24 and showed that wind shear is having a strong effect on the system.

On December 24, Tropical Cyclone Bruce's maximum sustained winds were near 40 knots/46 mph/ 4.0 kph and weakening. Bruce was centered near 31.9 south and 84.9 east, about 1,594 nautical miles south-southeast of Diego Garcia. Bruce has sped up in its movement in a southeasterly direction and was moving at 26 knots/29.9 mph 8.1 kph.

Satellite imagery showed that the low-level center is now exposed to outside winds and is quickly decaying. The Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard NASA's Aqua satellite captured a visible image of Tropical Cyclone Bruce on Dec. 24 at 08:25 UTC/3:25 a.m. EST. The MODIS image confirmed the strongest thunderstorms have been pushed southeast of the center from the northwesterly wind shear.

Bruce is also becoming embedded within the mid-latitude westerlies (winds) and is forecast to become extra-tropical low late on December 24, and later into a remnant low pressure area.

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


Dec. 23, 2013 - NASA Sees Tropical Cyclone Bruce Lose its Eye [image-124][image-140]

Tropical Cyclone Bruce's eye caught the eye of NASA's Aqua satellite when it passed overhead on December 21, but two days later, Bruce's eye appeared cloud-filled on satellite imagery.

On Dec. 21, Bruce still remained at hurricane strength as it continued moving through the Southern Indian Ocean. NASA's Aqua satellite passed over Tropical Cyclone Bruce on Dec. 21 at 0800 UTC/3:00 a.m. EST and saw its very distinct eye. On December 23 at 0500 UTC/12 a.m. EST when NASA's Terra satellite flew over Bruce, the MODIS instrument aboard captured a photograph that showed the eye had become cloud-filled. The Terra image also showed that Bruce had become elongated as a result of wind shear.

On December 23 at 1500 UTC/10 a.m. EST, Bruce's maximum sustained winds were near 80 knots/92.0 mph/148.2 kph, so it was still hurricane-strength, although weaker than it was over the two days previous. Bruce was centered near 24.5 south and 78.3 east, about 1,096 nautical miles south-southeast of Diego Garcia and moving to the south-southeast at 16 knots/18/4 mph/29.6 kph.

Bruce is expected to turn east over the next day. The Joint Typhoon Warning Center expects Bruce to weaken rapidly because of wind shear, movement into cooler waters, and becoming embedded in westerly winds.

Bruce is expected to start to turn extra-tropical later today, December 23, and by December 25 will be a remnant low pressure area.

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

 

 

 

 

 

 

 

 

 

 


Dec. 20, 2013 - NASA Sees Powerful Tropical Cyclone Bruce Staying Away from Land [image-94]

Tropical Cyclone Bruce continued to strengthen over wide open waters of the Southern Indian Ocean and NASA satellite data showed its eye had cleared of clouds. Bruce is forecast to stay away from land areas and weaken over the next four days.

The Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard NASA's Terra satellite captured a visible image of a more wide-eyed Tropical Cyclone Bruce on Dec. 20 at 04:30 UTC. In the satellite image, the ocean surface was visible in the center of Bruce's 25 nautical-mile/28.7 mile/46.3 km-wide eye.

As of 1500 UTC/10 a.m. EST on Dec. 20, Bruce had rapidly intensified by 35 knots/40.2 mph/64.8 kph over the previous 24 hours and an astonishing 70 knots/80 mph/129.6 kph over the previous 48 hours.

Tropical cyclone Bruce had maximum sustained winds near 125 knots/143.8 mph/231.5 kph on Dec. 20 at 1500 UTC/10 a.m. EST. That makes Bruce equivalent to a Category 4 hurricane on the Saffir-Simpson Scale. Bruce was creating very rough seas, generating waves as high as 30 feet/9.1 meters. Bruce was centered about 505 nautical miles/581.1 miles/935.3 km  west-southwest of Cocos Island, Australia near 13.8 south latitude and 87.5 east longitude. Bruce is moving to the west-southwest at 9 knots/10.3 mph/16.6 kph.

Forecasters at the Joint Typhoon Warning Center described Bruce's structure from animated multispectral satellite imagery as a "classic tropical cyclone structure with a deeply convective, symmetric eyewall surrounded by spiraling feeder bands in all quadrants."

In two days an approaching mid-latitude shortwave trough (elongated area) of low pressure moving in from the southwest will cause Bruce to curve to the southeast. The Joint Typhoon Warning Center expects Bruce to become extra-tropical after three of four days.

Text credit:  Rob Gutro

NASA's Goddard Space Flight Center


Dec. 19, 2013 - NASA Sees Tropical Cyclone Bruce Still Wide-Eyed [image-78]

Tropical Cyclone Bruce was still maintaining hurricane-force in the Southern Indian Ocean when NASA's Terra satellite passed over the eye of the storm.

The Moderate Resolution Imaging Spectroradiometer instrument known as MODIS takes amazing visible and infrared images of tropical cyclones, among other things, and captured a good look into the eye of Bruce on Dec. 19 at 03:41 UTC. Although Bruce's eye seemed to have some high clouds, the eye was still visible. Also visible by MODIS were thick bands of thunderstorms wrapping around the storm's northern quadrant. Convection (rising air that forms the thunderstorms that make up a tropical cyclone) was seen strengthening around the eyewall.

On December 19 at 1500 UTC, Tropical Cyclone Bruce's maximum sustained winds were near 90 knots/103.6 mph/166.7 kph. Bruce was centered near 12.7 south and 90.7 east, about 330 nautical miles/379.8 miles/611.1 km west of Cocos Island, Australia. It was moving to the west-southwest at 10 knots/11.5 mph/18.5 kph.

Bruce is moving along the northern edge of an elongated area of subtropical high pressure and is expected to continue moving to the west-southwest for another three days according to the Joint Typhoon Warning Center.

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


Dec. 18, 2013 - NASA Sees Tropical Cyclone Bruce Develop Near Cocos Island [image-51]

NASA's Aqua satellite flew overhead as the fourth tropical cyclone of the Southern Indian Ocean cyclone season developed today, December 18, while it was passing to the northwest of Cocos Island, Australia.

The MODIS or Moderate Resolution Imaging Spectroradiometer instrument that flies aboard NASA's Aqua satellite captured Tropical Cyclone Bruce's developing eye in a visible image taken on Dec. 18 at 07:30 UTC/2:30 a.m. EST. Animated multispectral satellite imagery showed that the low-level circulation center was consolidating and there was an improvement in the banding of thunderstorms around the elongated center. The Atmospheric Infrared Sounder instrument that also flies aboard Aqua more clearly showed the developing eye. The infrared data showed cloud top temperatures, and around the center cloud tops were as cold as -63F/-52C, while the center was devoid of high, cold clouds, providing a more clear indication of a developing eye.

When NASA's Tropical Rainfall Measuring Mission or TRMM satellite passed over Bruce on Dec. 18 at 407 UTC/Dec. 17 at 11:07 p.m. EST, data showed that the bands of thunderstorms were fragmented, but tightly wrapped into the center.  

On December 18 at 0900 UTC/4 a.m. EST, Tropical Cyclone Bruce had maximum sustained winds near 50 knots/57.5 mph/92.6 kph making it a tropical storm. Bruce is expected to strengthen over the next several days and reach hurricane/typhoon strength before weakening. Bruce was centered just 108 nautical miles/124.3 miles/200 km northwest of Cocos Island, near 10.9 south latitude and 95.5 east longitude. It was moving to the southwest at 9 knots/10.3 mph/16.6 kph.

The Australian Bureau of Meteorology noted on December 18 at 11:00 a.m. EST, that winds affecting the Cocos Islands eased below gale force as Tropical Cyclone Bruce continues moving away.

Bruce is expected to track to the west-southwest and intensify over the next couple of days as it moves over open ocean.

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

Image Token: 
[image-36]
The infrared instrument aboard NASA's Aqua satellite clearly shows the developing eye in Tropical Cyclone Bruce on Dec. 18.
The infrared instrument aboard NASA's Aqua satellite clearly shows the developing eye in Tropical Cyclone Bruce on Dec. 18 at 07:23 UTC/2:23 a.m. EST.
Image Credit: 
NASA JPL/Ed Olsen
Image Token: 
[image-51]
MODIS image of Bruce
NASA's Terra satellite passed over the center of Tropical Cyclone Bruce on Dec. 19 at 03:40 UTC and the MODIS instrument captured this image, clearly showing an eye.
Image Credit: 
NRL/NASA
Image Token: 
[image-78]
MODIS image of Bruce
NASA's Terra satellite captured this visible image of Tropical Cyclone Bruce in the Southern Indian Ocean on Dec. 20 at 04:30 UTC.
Image Credit: 
NASA Goddard MODIS Rapid Response
Image Token: 
[image-94]
Image Token: 
[image-110]
Aqua image of Bruce
NASA's Aqua satellite passed over Tropical Cyclone Bruce in the Southern Indian Ocean on Dec. 21 at 0800 UTC/3:00 a.m. EST and saw its very distinct eye.
Image Credit: 
NASA Goddard MODIS Rapid Response Team
Image Token: 
[image-124]
Terra image of Bruce
NASA's Aqua satellite passed over Tropical Cyclone Bruce in the Southern Indian Ocean on Dec. 23 at 0500 UTC/12:00 a.m. EST and its eye had become cloud-filled.
Image Credit: 
NASA's Goddard MODIS Rapid Response Team
Image Token: 
[image-140]
MODIS image of Bruce
The MODIS instrument aboard NASA's Aqua satellite captured this visible image of Tropical Cyclone Bruce on Dec. 24 at 08:25 UTC/3:25 a.m. EST. Most of the precipitation was southeast of the center.
Image Credit: 
NRL/NASA
Image Token: 
[image-156]
Page Last Updated: December 24th, 2013
Page Editor: Lynn Jenner