Cyclonic Storm Phyan developed as a tropical disturbance to the southwest of Colombo in Sri Lanka on November 4, 2009.
After the disturbance emerged into the Arabian Sea, it rapidly became more of a concern to the India Meteorological Department (IMD) reporting early on November 9 that the disturbance had intensified into a Depression, and designated it as Depression ARB 03 whilst the Joint Typhoon Warning Center (JTWC) issued a Tropical Cyclone Formation Alert.
[3][4][5] Early on November 9, as a Tropical Cyclone Formation Alert was issued by the JTWC; the India Meteorological Department (IMD) reported that the disturbance had become a depression and designated it as Depression ARB 03 as multiple bands of deep convection had started to consolidate around the now well-defined low-level circulation center.
The IMD further reported later that day that the deep depression had reached its peak windspeeds of 65 km/h (40 mph) 3-min sustained, which made it a Cyclonic storm with it being named as Phyan whilst located about 500 km (310miles) to the southwest of Mumbai as it moved into an area of high vertical wind shear.
[9][10] Early on November 11 the JTWC reported that Phyan had reached its peak intensity of 95 km/h (60 mph), before the Cyclone made landfall in Maharashtra between Alibagh and Mumbai later that morning.