Weather
Kalbaishakhi Storms 2026: Nor'wester Forecast, Signals and Safety Guide for West Bengal
What a Kalbaishakhi or nor'wester storm is, when it strikes, what IMD's colour-coded warnings mean, and how to keep your home, crops and family safe before and after the storm — a complete guide.
Frequently Asked Questions (FAQ)
When do Kalbaishakhi storms occur?
Mainly during the months of Chaitra and Baisakh, i.e. from mid-March to the end of May, in the afternoon and evening. Before the south-west monsoon arrives, dry cold north-westerly winds combine with humid air from the Bay of Bengal to create these storms.
What does IMD's red alert mean?
A red alert means extremely dangerous weather — with the risk of major loss of life and property. Under this signal, staying indoors is best. Orange means stay very alert, yellow means stay aware.
What should farmers do before a Kalbaishakhi?
Harvest ripe paddy and wheat quickly and bring them indoors, cover the grain heaps with tarpaulin, move livestock from open areas to shelter, and shift any crops stored near electric poles.
In detail
On a Baisakh afternoon the sky suddenly darkens, elephant-tusk-shaped clouds rise on the north-western horizon, and within an hour thunderous gales topple trees and electricity poles — that is the Kalbaishakhi or nor’wester. Speeds reach 60 to 100 kilometres/hour, accompanied by torrential rain and hail in places.
Why Does the Kalbaishakhi Happen?
In the heat, the dry air of north-west India meets the humid air arriving from the Bay of Bengal — this collision creates towering cumulonimbus clouds, whose cold upper layer collapsing gives birth to the storm winds. That is why a wall of white cloud is seen on the horizon before the storm arrives, and the temperature drops suddenly.
IMD’s Colour-Coded Warnings
| Signal | Meaning | What to Do |
|---|---|---|
| Yellow | Stay aware — possibility of a light-to-moderate storm | Keep track of the weather |
| Orange | Stay alert — risk of damage | Avoid going out unnecessarily |
| Red | Danger signal — risk of major damage | Stay indoors, watch emergency helplines |
For updates, see IMD Kolkata’s official page or our weather section.
Before the Storm
- Outside the house: tie down or bring inside rooftop items (tin sheets, plastic tanks, bamboo)
- Electricity: never splice damaged wires; after the storm, don’t touch fallen wires
- Mobile: keep your phone charged; keep torches and candles ready
- Crops: harvest ripe crops in advance and bring them indoors; cover the grain stores
During the Storm
- No open fields, beaches or riverbanks — stay inside a strong building
- Keep away from trees, billboards and poles
- Keep windows shut; during lightning, avoid water taps and landlines
After the Storm
- Report broken power lines to the electricity department instead of going near them
- Overflowing water brings dengue and diarrhoea risk — dry up standing water
- If someone is injured, dial 108 (ambulance) or 112 (emergency services)
In southern Bengal the most Kalbaishakhi-active districts are Bankura, Birbhum, West and East Medinipur, Howrah, Hooghly and Nadia. For region-specific information on each district, see District Info.
Related topics
- Kalbaishakhi
- nor'wester storm
- Kalbaishakhi forecast
- storm warnings
- Kalbaishakhi 2026
- what is a Baisakhi storm
- IMD alert