Cyclone Emma (2006)

However, low wind shear and well-developed outflow gradually allowed convection to develop near the centre of circulation.

As the system approached the Pilbara coastline of Western Australia on 27 February, it intensified into a Category 1 cyclone and attained peak 10-minute sustained winds of 75 km/h (47 mph).

After moving inland near Mardie, Emma weakened to a tropical low but became exceedingly large; its cloud cover obscured most of Western Australia.

[1] By this time, the Bureau of Meteorology anticipated the low to develop into a tropical cyclone and attain winds of 95 km/h (59 mph) 10-minute sustained) before moving over land in Western Australia.

[4] During the day, a QuikSCAT pass revealed a broad low-level circulation with the highest winds located around the periphery of the storm, a characteristic of monsoonal systems.

Although it was situated within a region of low wind shear and underneath an anticyclone, convective activity was mostly present in the system's large outer bands.

[1] Later that day, the Bureau of Meteorology upgraded the system to a Category 1 cyclone on the Australian intensity scale and named it Emma.

[1] Several hours later, the JTWC classified Emma as Tropical Storm 15S[4] following the development of convection near the centre of circulation.

[1] The storm continued to track southward in response to a strong mid to upper-level ridge situated over central Australia.

[11] The same day, the Fire and Emergency Services of Australia issued a Yellow Alert[12] for Point Samson, Roebourne, Wickham, Dampier, Karratha, and Mardie.

[14] The 190 mm (7.5 in) of rain that fell in a 24-hour span in Karratha pushed the city above its annual average rainfall totals in the first two months of the year.

[19] In the Murchison region, rainfall exceeding 100 mm (3.9 in)[20] brought the worst floods in decades, inundating numerous farms and causing substantial agricultural losses.

[24] Several stations in the area remained under water for over a month and farmers requested urgent assistance from the government to help alleviate losses.

[26] Due to the combined effects of Cyclones Clare, Darryl, Jim, Emma, Kate and Glenda, gold production in Australia fell by 8 percent, resulting in earnings losses of A$130 million.

Map plotting the storm's track and intensity, according to the Saffir–Simpson scale
Map key
Tropical depression (≤38 mph, ≤62 km/h)
Tropical storm (39–73 mph, 63–118 km/h)
Category 1 (74–95 mph, 119–153 km/h)
Category 2 (96–110 mph, 154–177 km/h)
Category 3 (111–129 mph, 178–208 km/h)
Category 4 (130–156 mph, 209–251 km/h)
Category 5 (≥157 mph, ≥252 km/h)
Unknown
Storm type
triangle Extratropical cyclone , remnant low, tropical disturbance, or monsoon depression
The Murchison River at the height of the flooding on 16 March (top) compared to its normal level (bottom)