Machilipatnam city gets most of its annual rainfall due to the southwest monsoon. It has a tropical savanna climate (Köppen climate classification Aw) with hot summers and moderate winters. The hottest months are between April and June. The average normal rainfall in the district is 959 millimetres (37.8 in).
Machilipatnam city is frequently hit by cyclones originating in the Bay of Bengal. The Andhra Pradesh coast between Ongole and Machilipatnam is vulnerable to high surges of the sea due to cyclones. The Andhra Cyclone of 14–20 November 1977 crossed the coast near Nizampatnam and took approximately 10,000 lives. As the storm approached the coast, gale winds reaching 200 km/h lashed Prakasam, Guntur, Krishna, East Godavari and West Godavari districts. A storm surge, 5 meters high, inundated the Krishna estuary and the coast south of Machilipatnam city (Bandar)
On 8 December 2004, a high capacity S-Band Doppler cyclone warning radar was installed, commissioned and made operational at the city. It was purchased from a German manufacturer, Gematronik. With the installation of the radar, the state will be better equipped to track cyclones by the onset of monsoon, according to an official from the State Met Office talking to the newspaper The Hindu. This facility will monitor the 960 km long coastline of the state. The radar's information is posted in real-time on the Indian Meteorological Department website. Similar radars were installed in other coastal cities forming an S-Band Cyclone Detection Radar Network
