More than a month-and-a-half into the season, the northeast or winter monsoon has generated excess rainfall of 19 per cent during the season so far (October 1 to November 18).
The season has been normal or above normal over the southern peninsula (except coastal Andhra Pradesh with a 27 per cent deficit), west-central, central, north and east India.
IN DEFICIT STILL
The northwest continued to disappoint, especially the bread baskets of Punjab and Haryana. But the entire Uttar Pradesh, Bihar, Madhya Pradesh, Jharkhand and Maharashtra returned gains in excess of the usual.
Chhattisgarh (22 per cent); Gangetic West Bengal (35 per cent) and Arunachal Pradesh (29 per cent) too have run up varying deficits during this period.
Leading international models had suggested that November would likely see northwest India being left in the lurch while peninsular India would make the most gains.
The India Meteorological Department's (IMD) rainfall maps showed the `gateways' in the northwest - Punjab, Haryana, west Rajasthan and Saurashtra-Kutch - reporting scanty rainfall.
But model predictions favour comparatively better times going further into the winter for these regions.
They get their seasonal rains from western disturbances of significant magnitude with embedded cyclonic whirls.
Most of the rains generated during the season until now have fallen eastward from Uttarkhand, west Uttar Pradesh, east Rajasthan and Gujarat.
Some qualitative change to the scenario was discernible only during the latest week (ending Wednesday) when west Rajasthan alone posted scanty rainfall and Saurashtra-Kutch, deficient - the rest of the country had excess rainfall.
MORE RAINS
Meanwhile, the US National Centres for Environmental Prediction (NCEP) saw more rain being generated over Sri Lanka and along the Tamil Nadu coast during November 19 to 26.
The entire southeast and southwest Bay of Bengal and adjoining East Indian Ocean, a `hotspot' for quite sometime now, will continue to set up weather for the southern peninsula during this phase.
The realised rains are expected to be normal over Tamil Nadu but in excess over the west coast, especially around coastal Karnataka, according to the NCEP outlook.
The following week (November 27 to December 5) is forecast to see a fresh wave of rains approach the Tamil Nadu coast from the east and the southeast.
The European Centre for Medium-Term Weather Forecasts (ECMWF) too, agrees and picked successive cyclonic circulations patrolling the southeast and adjoining southwest Bay of Bengal from Sunday to Tuesday.
A broad area of lower pressure may get thrown up covering the south Andaman Sea and adjoining southeast Bay of Bengal around midweek next week. This should trigger a conventional `low' in the region the next day or the day after.
This could well be the causative feature of the rains that the NCEP sees falling over India's southeast coast and adjoining Sri Lanka during the next week and possibly into early December.
VIGORUS MONSOON
An update from the Regional Met Centre, Chennai, said that the northeast monsoon has been vigorous over south coastal Andhra Pradesh during the 24 hours ending Thursday morning.
Forecast for the next two days said that rain or thundershowers are likely at a few places over Tamil Nadu, Puducherry, Kerala, Lakshadweep, Andhra Pradesh and Karnataka.
The cyclonic circulation over south Tamil Nadu and adjoining Kerala persisted on Thursday. But the trough from south Konkan coast to Chhattisgarh that emptied rains over central and east-central India during the past few days has weakened.
REMNANT WHIRL
It has, however, left behind a cyclonic circulation over south Chhattisgarh and adjoining coastal Andhra Pradesh. Another cyclonic circulation lay over Madhya Maharashtra and neighbourhood.
Strong northwesterly to westerly winds are prevailing over the Indo-Gangetic plains. The northwesterly component is what brings in the `chill factor' into focus over the region.
The IMD said that minimum temperatures are likely to fall by 1 to 2 degree Celsius over northwest India and by 2 to 4 degree Celsius over central and adjoining east India during the next three days.
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