A prevailing low-pressure area in the Bay of Bengal beat all forecasts to intensity with blinding speed into a deep depression overnight and crossed Bangladesh coast early this morning.
This had escalated the strength of the system to only a notch below tropical cyclone status, as the deep depression crossed the Bangla coast near Khepupara between 4.30 am and 5.30 am.
RARE DURING MONSOON
No weather model had forecast this scale of intensification, since it is rare for systems beyond depression to take birth in the Bay or the Arabian Sea once the monsoon has established.
India Met Department (IMD) had yesterday put out a watch for the ‘well-marked low’ in the Bay to become a depression today and apparently hoped it would drop anchor there.
But outlook from a few centres, including the US National Centres for Environmental Predictions, had pointed towards a ‘flare-up’ during the weekend around the Bengal-Bangladesh coast.
Still, it was unimaginable that the Bay would host a deep depression, even if fleetingly, at a time when the monsoon had established itself over the country and the neighbouring seas.
ANOTHER ‘LOW’ BREWING?
Meanwhile, a reliable US weather tracker as also the European Centre for Medium-range Weather Forecasts looked to the Bay for signs for another building ‘low’ in a week’s time.
This ‘low’ would help reorganise the monsoon flows in the Bay and train a bulk of them to steer themselves and head back into East India, and not stray into Bangladesh.
The US tracker shows the ‘low’ moving over East India and further on to North-West India in what is considered a time-tested track for these systems to move to sustain monsoon conditions.
The European centre showed the land-based trough from North-West India linking the Bay through Uttar Pradesh and Bihar, shaping up to host a ‘low’ around June 20.
SOUTH MAY STAY DRY
The US National Centres for Environmental Prediction supports this outlook with a predicted rainfall scenario that sits heavy over East India and the West Coast during the week from June 19.
The US Climate Prediction Centre could not agree more, and is more emphatic about a heavy rainfall scenario for East India and the Konkan-Mumbai coast and South Gujarat during June 18 to 24.
But rainfall will be mostly below normal for most parts of the South Peninsula and adjoining Central India expect West Madhya Pradesh during this week.
This would represent further drying up of these parts relative to conditions during the immediate previous week (June 11-17, the ongoing week).