Rare Tropical Cyclone Alessia about to impact western Australia

An unusually early-season tropical cyclone developed in the Indian Ocean between Indonesia and Western Australia and will continue its slow journey eastward, reaching the northwestern part of the Australia by the end of the weekend.

The Australian cyclone season officially starts in November, but tropical activity typically holds off until December.

Tropical Cyclone Alessia formed off of Western Australia's Kimberley coast and the first Cyclone Warnings and Watches of the season are now in effect. According to the bulletin from the Australian Bureau of Meteorology or ABM, gales may develop along the northern Kimberley coast on November 23 as Alessia approaches the coast. The tropical cyclone is expected to brush the northern Kimberley coast and weaken as it approaches the west coast of the Top End on November 24, 2013.

TC Alessia forecast track (Credit: JTWC)

According to latest report by Joint Typhoon Warning Center (JTWC), the center of Tropical Cyclone Alessia was located approximately 490 nm west-southwestward of Darwin, Australia. The system is moving eastward at 12 knots. 

Alessia is expected to track over the waters of the Timor Sea, then near the far northern tip of Western Australia's Kimberley region and into the Northern Territory. If the system cross land and enters the warm waters of the Gulf of Carpentaria it could gain more strength but it's more likely that it will dissipate over the land.

MTSAT AVN Infrared image taken at 21:30 UTC on November 22, 2013 (Credit: NOAA/MTSAT)

Rain amounts of 75 to 150 mm (3 to 6 inches) and gusty winds of 60 to 80 km/h (40 to 50 mph) are expected across the region. The storm should have the intensity of a minimal tropical storm in the Atlantic or Pacific basins.

Satellite Animations

• Storm-Centered Infrared (Meteosat 7; NOAA/SSD)
• Storm-Centered Infrared (Aviation Color Enhancement) (Meteosat 7; NOAA/SSD)
• Storm-Centered Water Vapor (Meteosat 7; NOAA/SSD)
• Storm-Centered Visible (Meteosat 7; NOAA/SSD)
• Storm-Centered Visible (Colorized) (Meteosat 7; NOAA/SSD)

• Storm-Centered Infrared (Meteosat 7; CIMSS)
• Storm-Centered Enhanced Infrared (Meteosat 7; CIMSS)
• Storm-Centered Water Vapor (Meteosat 7; CIMSS)
• Storm-Centered Visible (Meteosat 7; CIMSS)

• MTSAT Infrared (MTSAT; CIMSS)
• MTSAT Infrared (Color Background) (MTSAT; CIMSS)
• MTSAT Infrared (NHC Color Enhancement (MTSAT; CIMSS)
• MTSAT Water Vapor (MTSAT; CIMSS)
• MTSAT Water Vapor (Color Background) (MTSAT; CIMSS)
• Meteosat 7 Infrared (Meteosat 7; CIMSS)
• Meteosat 7 Infrared (Color Background) (Meteosat 7; CIMSS)
• Meteosat 7 Infrared (NHC Color Enhancement) (Meteosat 7; CIMSS)
• Meteosat 7 Water Vapor (Meteosat 7; CIMSS)
• Meteosat 7 Water Vapor (Color Background) (Meteosat 7; CIMSS)

Featured image: TC Alessia on November 22, 2013 (Credit: LANCE Rapid Response/MODIS/Worldview)