{News} 080614 Full monsoon coverage with 14-day lead time seen

Full monsoon coverage with 14-day lead time seen

Vinson Kurian
The Hindu Business Line,14 June 2008

Thiruvananthapuram, June 13 A fleet-footed monsoon persisted with its hurried run into the northwest on Friday calling in at Rajasthan, Haryana and Punjab, having covered entire Uttarakhand, Himachal Pradesh and Jammu and Kashmir.
It is knocking at the doors of the National Capital, and the India Meteorological Department (IMD) said the entire country would be brought within its footprint over the next three days, almost a fortnight ahead of July-1 normal.
Significantly for this year, the monsoon is imposing itself upon the north and northwest which has already seen excess precipitation during the just concluded `freak’ summer. Back-to-back western disturbances dumped heavy rain over these regions during the period. IDEAL CONDITIONS
The moisture available thus could ignite the firepower of monsoon systems as they run in one by one. In what were most ideal monsoon conditions on Friday, an upper air cyclonic circulation hung over west Uttar Pradesh and a western disturbance over the western Himalayan Region.
The whirl over west Uttar Pradesh would mass up around it moisture from the Bay while the embedded circulation with the westerly system would be the rallying point for the moisture feed from the Arabian Sea.
The interaction of the two systems promises to trigger heavy rains over east India and northwest India. Monsoon systems and western disturbances have produced heavy to very heavy precipitation and represent the most active phase of the monsoon in the region. `LOW’ SOON
This apart, a full-fledged monsoon `low’ (even a depression) is forecast to materialise over the northwest Bay within the next three days. This would only help further rev up the proceedings.
Good rainfall has already been reported over central and northwest India, and on Friday the monsoon advanced into the some more parts of Arabian Sea, most parts of Gujarat, some parts of east Rajasthan, some more parts of Madhya Pradesh and east Uttar Pradesh. The northern limit passed through Deesa, Udaipur, Guna, Jhansi, Fatehpur, Bahraich, Pantnagar, Patiala and Jammu.
The all-important seasonal monsoon trough has rolled out itself from northwest (Rajasthan/Haryana) to southeast (Bay of Bengal) opening the doors for monsoon easterlies to fill the Indo-Gangetic plains with moisture.
The trough was traced from Ferozepur, Muzaffarnagar, Lucknow, Hazaribagh, Sagar Island and southeastwards into the east-central Bay of Bengal. It offers the ideal incline for Bay `low’s to travel into the country’s farming heartland.
An otherwise rosy picture has been blotted by rainfall deficits only at the monsoon gateways of Kerala and the Northeastern States; and in Marathwada and Daman and Diu. But the deficit would be more than made up over the next few days, say experts.
A positive Indian Ocean Dipole (IOD) and a passing Madden-Julian Oscillation (MJO) wave of enhanced precipitation traversing the Indian Ocean are perceived to be the two ocean-triggered phenomena driving the active phase of the monsoon.
The positive IOD event is forecast to last through June-July-August, while, according to the Constructed Analogue (CA) model of the US National Weather Services-Climate Prediction Centre (NWS-CPC), the current MJO phase could last until June 26.

Source: http://www.blonnet.com/2008/06/14/stories/2008061450131200.htm