Western Disturbances
With the Southward shift of the polar front in winter, the tracks of the middle latitude cyclones pass across the northern portion of the Indian subcontinent during the period October to June. In the Other months the tracks shifts far to poleward and do not usually affect the Indian region.
The temperate cyclones originates in Western Asia and Mediterranean sea and reach the Indian area in the course of their is toward passages from West India and refer to as Western disturbances.These Western disturbances causes-
- Snowfall in higher reaches of Himalayas.
- Rainfall in North West Plains fish are beneficial for Ravi crop.
- The second cold wave that decreases the temperature of that areas and heel also takes place.
Local winds
During summers the atmospheric pressure is low all over the country. In the months of May and June high temperature in the Northwest India builds up steep pressure gradient and under such conditions dust Laden and strong winds blows.
- LOO: it is hot dust Laden winds that usually start in morning and reaches its peak at afternoon this increases the temperature of the area and college high humidity.
- AANDHIS: These are basically thunder Storms which move like a solid wall of dust and sand. The winds velocity is high and visibility reduces to few metres only. such dust Storms are common in Rajasthan, Haryana,Delhi, Uttar Pradesh.
In West Bengal and adjoining areas of Jharkhand,Orissa the direction of storm is mainly from the North West and are called NORWESTERS
KAL BAISAKHIS: these are violent Storms causes heavy damage to standing crops live stocks and human beings maximum occurs in month of March and April.
