A weak system for much of its duration, Keila developed in the western Arabian Sea in late October 2011, amid an area of marginally favorable conditions.

Given the name Keila by the India Meteorological Department (IMD), the storm quickly moved ashore southern Oman near Salalah, and weakened while meandering over the country.

Offshore, Keila capsized a boat originating from India, killing five of the crew and leaving another nine missing; six sailors were rescued by the Omani Coast Guard.

[3] On October 29, the India Meteorological Department (IMD) designated the system as Depression ARB 02 about 885 km (550 mi) east of the Yemeni island of Socotra.

By that time, the agency estimated peak 3 minute sustained winds of 65 km/h (40 mph) while the storm was just 150 km (95 mi) southeast of Oman.

[6] With cool waters and an unfavorable phase of the Madden–Julian oscillation, Keila failed to intensify significantly as it approached the southeastern Arabian Peninsula.

[1] However, the JTWC tracked the system further in a post-season analysis, estimating that Keila intensified once offshore and attained peak winds of 100 km/h (60 mph) on November 3.

[9] There was confusion in the country over Keila's intensity; the IMD classified it as a cyclonic storm, while officials in Oman designated it as a deep depression,[10] based on available observations.

[14] Moisture from the storm coalesced over the Al Hajar Mountains in northern Oman, producing severe thunderstorms that led to flash flooding.

[12] In the valley near Al-Rustaq, floodwaters swept away cars, dead animals, and property, with water levels reaching 1.8 m (5.9 ft) high in some places.

[11] Sailing from the Indian state of Gujarat to Dubai, a ship with the call sign MSV Shiv Sagar MNV 2169 encountered Keila offshore southern Oman.