India Meteorological Department's (IMD) outlook does not provide any signal to the onset of north-east monsoon at least until October 24.
Available indications from international models suggest that the flows have indeed changed to being easterly and partly north-easterly over the peninsula.
POOR STRENGTH
But they are lacking in speed, largely due to the absence of a steering mechanism in the Bay of Bengal. What the basin has currently to offer is a weak trough/wind discontinuity to the south-west where north-easterlies jostle for space with remnant south-westerlies.
IMD charts on Monday showed a weak circulation over Sri Lanka and adjoining Tamil Nadu helping sustain the flows over the southern peninsula.
This could bring isolated showers over parts of the southern peninsula. Meanwhile, the Global Forecasting System model prognosis given out by the US National Centres for Environmental Prediction valid until October 27 suggested that the north-easterly flows may pick up some speed but largely skirt the peninsular coast to blow into Sri Lanka.
This is the phase when Typhoon Lupit, the latest strong weather system to stalk the west Pacific and the adjoining South China Sea, is forecast to tear into land twice over - the Philippines, followed by Vietnam/South China.
According to the London-based Tropical Storm Risk Group, Lupit is likely to achieve Category-4 strength, the second highest on the Saffir-Simpson scale of storm intensity, before weakening slightly on landfall.
The European Centre for Medium-Range Weather Forecasts sees Lupit sliding into the South China Sea just west of the Philippines and gathering strength once again into typhoon status. It is forecast to head straight to the west, and would possibly brush past Hong Kong to make an eventual landfall over South China-Vietnam region around October 27-28.
The north-west to south-easterly flows associated with Lupit could likely take away available moisture in the Bay of Bengal, which explains the wind divergence leading to formation of wind discontinuity.
But the Bay would be watched for any remnant circulation that could be left behind by Lupit for triggering north-east monsoon.
The International Research Institute for Climate and Society at Columbia University has come out with its seasonal forecast suggesting maximum probability for excess showers for Sri Lanka during October-November-December.
SHARING SPOILS
Parts of adjoining south-east Tamil Nadu too are forecast to share the spoils while no big deviation from the usual pattern is forecast for the rest of the peninsula and the country at large.
An IMD outlook for the country said that isolated rain/thundershower activity could be expected over parts of northeast India during next two days. .
Minimum temperatures were above normal by 2 to 3 deg Celsius over parts of Rajasthan. But they are below normal by a same margin over parts of east Uttar Pradesh, interior Orissa, west Madhya Pradesh and interior Karnataka.
The mercury is expected to fall by about 2 deg Celsius over parts of Rajasthan and Chhattisgarh during the next two days.
Satellite imagery on Monday showed convective clouds over parts of the Andaman Sea and south-west Arabian Sea. Isolated rain or thundershower has been forecast over Andaman and Nicobar Islands, south coastal Tamil Nadu, Kerala and Lakshadweep.
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