The IMD issued extremely heavy rainfall warnings for Odisha, Andhra Pradesh and Telangana on September 23, as a deep depression over the Bay of Bengal heads toward the coast near Kalingapatnam.

Weather warnings use graded language for a reason: ‘extremely heavy’ sits above ‘very heavy’, which itself sits above ordinary heavy rain categories. Chhattisgarh’s separate ‘very heavy’ warning signals a real but comparatively lower risk than the coastal states directly in the depression’s path.

The specificity in this warning, naming Kalingapatnam and a landfall window of Wednesday night, reflects how far weather forecasting for tropical systems has advanced: agencies can now narrow a landfall point to a stretch of coast and a rough time window days in advance.

The accompanying safety advisories, about waterlogged roads, lightning shelter and marine warnings, matter as much as the rainfall numbers themselves, since most weather-related harm during such events comes from people underestimating familiar risks like flooded roads rather than the storm itself.

For residents in the warned states, the practical takeaway is less about the exact rainfall figure and more about treating a red-level warning as a signal to actually follow the specific advisories issued alongside it.

People were also advised to seek shelter indoors during lightning and to stay away from open fields and isolated trees.

Local administrations in low-lying and drainage-prone areas were asked to stay alert.

The system follows an earlier spell of heavy rain over the same region on September 21-22, as the depression intensified over the Bay of Bengal.

Bengaluru was separately forecast to see thunderstorms with lightning and gusty winds of around 30-40 kmph.

Delhi-NCR was not under any rainfall warning for September 23.

The India Meteorological Department is the government’s nodal agency for weather forecasting and warnings.

Deep depressions of this kind are common over the Bay of Bengal during the post-monsoon and late monsoon period in September and October.

Bay of Bengal weather system (representative satellite image), Wikimedia Commons, public domain