Earth Snapshot RSS Feed Twitter
 
 
 
 

Posts tagged Antananarivo

Area of Convection by Madagascar Strengthens into Tropical Cyclone Haruna (16S)

22.1S 37.2E

February 19th, 2013 Category: Tropical Cyclones

Tropical Cyclone Haruna (16S) – February 19th, 2013

Enhanced image

Track of Tropical Cyclone Haruna (16S) - February 19th, 2013 © Univ. of Wisconsin

Track of TC 16S

The area of convection near Madagascar (click here for previous images) has now strengthened into Tropical Cyclone Haruna (16S). The system is located approximately 385 nm west-southwest of Antananarivo, Madagascar, and has tracked westward at 04 knots over the past six hours.

Animated infrared satellite imagery indicates rapid consolidation over the past twelve hours with tightly-curved deep convective banding wrapping into a well- defined center. An SSMI 37 ghz image depicts a microwave eye feature and supports the initial position with high confidence. Based on the SSMI image and previous microwave imagery, the system motion has become quasi-stationary and appears to be looping.

Upper- level conditions remain very favorable with weak vertical wind shear, radial outflow and warm SST. Over the past twelve hours, the subtropical steering ridge (STR) has weakened due to an approaching shortwave trough and TC 16S is currently tracking slowly and erratically within a weak steering environment.

Dynamic model guidance supports slow track motion through TAU 48 until a deep shortwave trough deepens south of Madagascar. Thereafter, the system will accelerate southeastward while undergoing extra-tropical transition (ETT).

Area of Convection by Madagascar Remains With High Probability of Becoming Cyclone

22.3S 39.3E

February 18th, 2013 Category: Tropical Storms

Area of convection – February 18th, 2013

Enhanced image

Track of Area of Convection - February 18th, 2013 © Univ. of Wisconsin

Track of TC 15S

The area of convection previously located near 19.4S 40.0E (click here for previous images) is now located near 19.7S 41.1E, approximately 335 nm west of Antananarivo, Madagascar.

Animated infrared satellite imagery indicates a consolidating low-level circulation center (LLCC) with curved, deep convective banding over the eastern semi-circle. An SSMIS image depicts tightly-curved banding wrapping into a well-defined LLCC.

Recent scatterometer imagery as well as microwave- derived winds support 25 to 30 knot winds. Upper-level analysis indicates a point source near the center with near-radial outflow enhanced by an upper-level low positioned south of Madagascar. Vertical wind shear remains moderate (20 knots) and continues to hamper convective development over the western semi-circle. SST remains favorable at 29 to 30 degrees celsius.

Numerical models indicate development is likely over the next 12-24 hours. Maximum sustained surface winds are estimated at 25 to 30 knots. Minimum sea level pressure is estimated to be near 1000 mb. The potential for the development of a significant tropical cyclone within the next 24 hours remains high.

Area of Convection by Madagascar Now Has High Probability of Becoming Tropical Cyclone

21.2S 38.6E

February 18th, 2013 Category: Tropical Storms

Area of convection – February 17th, 2013

Enhanced image

Track of Area of Convection - February 18th, 2013 © Univ. of Wisconsin

Track of TC 15S

The area of convection previously located near 19.7S 39.9E (click here for previous images), is now located near 19.4S 40.0E, approximately 395 nm west of Antananarivo, Madagascar. Here, the coastline of Madagascar can be seen through the convection  thanks to the Chelys Satellite Rapid Response System (SRRS) “borders” feature.

Animated infrared satellite imagery shows formative bands that are consolidating and wrapping tighter into a broad low level circulation center (LLCC) from the northern and eastern peripheries.

Upper level analysis indicates the system is just south of a ridge axis that is enhancing outflow especially along the eastern flank; however, moderate (20 knot) vertical wind shear is displacing the main convection from the LLCC.

SSTs remain favorable for development at 29 to 30 degrees Celsius. Numerical models indicate development is likely over the next 24-36 hours, albeit with varying trajectories. Maximum sustained surface winds are estimated at 25 to 30 knots. Minimum sea level pressure is estimated to be near 1000 mb. Due to the improved overall structure of the system and the sustained favorable environmental conditions, the potential for the development of a significant tropical cyclone within the next 24 hours is upgraded to high.

Area of Convection by Madagascar Upgraded to Medium Chance for Tropical Cyclone Formation

20.1S 39.3E

February 17th, 2013 Category: Tropical Storms

Area of convection – February 16th, 2013

Enhanced image

The area of convection previously located near 16.5S 37.7E, is now located near 16.4S 38.4E, approximately 510 nm north- northwest of Antananarivo, Madagascar (click here for previous images). Here, the country’s coastline can be seen through the convection  thanks to the Chelys Satellite Rapid Response System (SRRS) “borders” feature.

The area of convection previously located near 16.5S 37.7E, is now located near 16.4S 38.4E, approximately 510 nm north- northwest of Antananarivo, Madagascar.

Animated infrared (IR) satellite imagery reveals formative banding wrapping into a low level circulation center (LLCC) that is located over Mozambique. The LLCC is tracking eastward, heading toward the open water of the Mozambique Channel. The IR and total precipitable water loops suggest that tight turning over the channel may be consolidating and forming a new LLCC.

Upper level analysis indicates a point source has developed over the system, providing good outflow. Vertical wind shear (VWS) is moderate (20 knots). Sea surface temperatures remain favorable for development at 29 to 30 degrees Celsius. Numerical models indicate development is likely over the next 48 hours. Maximum sustained surface winds are estimated at 20 to 25 knots. Minimum sea level pressure is estimated to be near 1003 mb. Due to improved banding and favorable conditions over the Mozambique Channel, the potential for the development of a significant tropical cyclone within the next 24 hours is upgraded to medium.

Area of Convection Off Coast of Madagascar

22.8S 37.9E

February 16th, 2013 Category: Tropical Storms

Area of convection – February 15th, 2013

Enhanced image

An area of convection is located near 21.2S 39.8E, approximately 425 nm west- southwest of Antananarivo, Madagascar. Here, the coast of Madagascar can be seen through the convection  thanks to the Chelys Satellite Rapid Response System (SRRS) “borders” feature, which overlays countries’ boundaries on satellite images.

The system is located just poleward of the subtropical ridge (STR) axis and is under weak to moderate (10 to 20 knots) westerly vertical wind shear (VWS). Sea surface temperatures are favorable at 29 to 30 degrees Celsius.

Animated multispectral satellite imagery depicts a well-defined lowlevel circulation center (LLCC) with formative convective banding over the eastern semi- circle. An SSMIS 37ghz microwave image shows fragmented shallow convection to the north of the LLCC.

Dynamic models indicate steady development over the next 2 to 3 days as the system tracks equatorward further under the STR with decreasing VWS. Maximum sustained surface winds are estimated at 20 to 25 knots. Minimum sea level pressure is estimated to be near 1003 mb. The potential for the development of a significant tropical cyclone within the next 24 hours remains low.

About Us

Earth Observation

Organisations

Archive

August 2018
M T W T F S S
« Mar    
 12345
6789101112
13141516171819
20212223242526
2728293031  

Categories


Bulletin Board


Featured Posts

Information

32


Take Action

Widgets