south indian ocean Moderate Tropical Storm Deliwe

[Somerset Squall]

JTWC have upgraded a tropical disturbance hugging the west coast of Madagascar to a 35kt tropical cyclone. MeteoFrance are still classifying the system as a tropical disturbance. Over the last couple days, the system has been moving south just inland, and has remarkably organised well despite this. 09S has now moved over the warm waters of the Mozambique Channel, and with low shear and superb outflow, the system has attained TC strength. 09S is forecast to head southwest for the next 36hrs as a steering ridge to the east remains the primary steering influence. A new ridge is then expected to build west of TC 09S, which may allow 09S to turn northwestwards and head towards central Mozambique, a scenario favoured by JTWC. MeteoFrance are forecasting a direct westward turn instead, favouring a landfall in southern Mozambique. A steering shift between two ridges is always difficult to forecast, so there are bound to be some changes in the track forecast. Both JTWC and MeteoFrance do agree that 09S should strengthen at least modestly over the next day or so, particularly as 09S moves away from the west coast of Madagascar, but shear is expected to rise on approach to Mozambique, so the cyclone is not expected to become particularly intense like the other cyclones we have seen to far in the 2013-14 South Indian Ocean season.

 

Edited January 16, 2014 by Somerset Squall

[Coast]

Tropical Storm NINE: Probability of Cat 1 or above winds to 120 hours lead

 

Tropical Cyclone NINE-14 can have a low humanitarian impact based on the Maximum sustained wind speed and the affected population and their vulnerability.

• Tropical Cyclone Tropical Storm (maximum wind speed of 93 km/h)
• on 16/01/2014 12:00 UTC
• Population affected by Category 1 (120 km/h) wind speeds or higher is 0
• Vulnerability: High

Extreme Rain

Potential rainfall is calculated based on rainfall observed by several microwave satellite sensors. The image shows the total rainfall accumulation associated with the cyclone.

 

Storm surge

The tropical cyclone did not reach sufficient strength to cause significant storm surge

 

 

http://www.gdacs.org/report.aspx?eventid=42505&episodeid=1&eventtype=TC

[Somerset Squall]

MeteoFrance have just upgraded the system to "Moderate Tropical Storm Deliwe".

[Somerset Squall]

Deliwe has strengthened to 45kts. The storm has developed a small central dense overcast but with limited banding. Strong poleward outflow will be countered by increasing shear from now, so JTWC do not forecast any further intensity gains, and forecast weakening once Deliwe makes the northwestward turn as the poleward outflow is expected to diminish at this point.

[Coast]

Tropical Storm DELIWE: Storm-centered zoom at 120 hours lead

 

Currently:

 

Edited January 17, 2014 by Coast

[Somerset Squall]

Strong shear has really knocked Deliwe for six today. Convection has been sheared away from an increasingly disorganised LLCC. Winds have dropped to 40kts according to JTWC. MeteoFrance however, have already downgraded Deliwe to a tropical depression. Either way, it doesn't look like Deliwe will prosper, as shear is not expected to ease.

[Coast]

 

The tropical depression southwest of Madagascar on January 16 developed into a tropical cyclone early on January 17 as NASA's Aqua satellite passed overhead and captured its birth.

 

When Aqua passed over newborn Tropical Cyclone Deliwe on January 17 at 10:55 UTC/5:55 a.m. EST the MODIS instrument or Moderate Resolution Imaging Spectroradiometer took a picture of it. Deliwe was previously known as Tropical Depression 09S. In the MODIS image bands of thunderstorms stretched west into the Mozambique Channel and south into the Southern Indian Ocean.

 

Forecasters at the Joint Typhoon Warning Center using multispectral satellite imagery indicated that Deliwe has a well-defined low-level center of circulation.

 

On January 17 at 0900 UTC/4 a.m. EST, Deliwe had maximum sustained winds near 45 knots/51.8 mph/ 83.3 kph. It was centered near 23.8 south and 42.0 east, about 375 nautical miles/431.5 miles/694.5 km southwest of Antananarivo, Madagascar. Deliwe is moving to the south-southwest. Deliwe is moving along the western edge of a subtropical ridge of high pressure centered east of Madagascar. As a new subtropical ridge of high pressure builds in west of the tropical cyclone, it is expected to turn and steer Deliwe to the northwest.

 

Forecasters at the Joint Typhoon Warning Center expect Deliwe to move southwest and then curve northwest. Computer models indicate that vertical wind shear is expected to increase after a day, and the tropical cyclone could dissipate in four days or before that.

 

 

 

http://phys.org/news/2014-01-nasa-satellite-birth-tropical-cyclone.html#jCp

[Somerset Squall]

Deliwe has dissipated over the Mozambique Channel. Regeneration is not expected due to persistantly strong shear.