Late on November 4, 2009, the
Joint Typhoon Warning Center (JTWC) reported that an area of
convection had started to deepen around a poorly organized and elongated
low level circulation center about 340 km (210 mi), to the southwest of
Colombo in
Sri Lanka. The low level circulation center was located in a region of upper level divergence which was providing a good channel for outflow, however it was also located in an area of moderate to high levels of
vertical wind shear. 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. Later on November 9, the JTWC reported that the depression had intensified into a tropical cyclone, designating it as 04A, with wind speeds equivalent to a tropical storm as organized deep convection increased around a consolidating low level circulation center. Early the next day the IMD reported that the depression had intensified into a Deep Depression as convection organized further. 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. 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. Later that day as the low level circulation center had rapidly detached from the deep convection the JTWC issued their final advisory whilst the IMD reported that Phyan had weakened into a depression before downgrading it to a well marked area of low pressure early on November 12. ==Preparations and impact==