Delhi, Wednesday, July 11 The southwest monsoon this year though entered a week late at the southern doorsteps of Kerala, has covered the entire country before its usual date of July 15. The India Meteorological Department (IMD) today announced the arrival of monsoon over west Rajasthan riding on rainfall ensuing from the monsoon trough passing through Bikaner.
West Rajasthan, the last frontier of the nation to be covered by the monsoon winds usually receives monsoon showers on July 15, marking the arrival well four days before schedule.
As of today, the monsoon is trailing by 23% of normal over the country as whole while the dearth is reported majorly from northwest and central India.
The axis of monsoon trough, essentially intensified moisture laden monsoon winds are extending from Bikaner, Gwalior, Fatehpur, Muzaffarpur and then passing on to northeast India. The weather formation is also passing through the low pressure area persisting over east Rajasthan.
The combined prowess of the monsoon trough and the low pressure would dispense rainfall over east Rajasthan, Delhi, parts of Haryana, Punjab, Himachal Pradesh and Uttarakhand during the next twenty four hours.
Troughs are places where winds from opposing directions meet (or winds turn) and atmospheric pressure is low while the turbulence caused by such interaction (or turning) leads to rain, thundershowers and storms.
This axis of monsoon trough is expected to oscillate north towards the Himalayan foothills in the next couple of days. Heavy rains are possible in this region while moderate rain over adjoining Uttar Pradesh during this period. Central Uttar Pradesh is also likely to be under the ambit of rainfall as the trough moves up massing through the region.
Rainfall activity would decrease along the west coast after twenty four hours and also over Gujarat. Significant showers are also ruled out over southern parts of the country.
Another north- south trough is prevailing from sub-Himalayan West Bengal to north Bay of Bengal and would be instrumental in increasing rainfall over northeast India in the next forty-eight hours. Sikkim and sub Himalayan West Bengal may receive moderate to isolated heavy rainfall during this period.