Monsoon hold-up in parts of east, central India may last until Sunday

India Meteorological Department (IMD) has said in a special bulletin on Tuesday that monsoon is unlikely to advance into the remaining parts of east and central India during the next four days.
But some weather models predict that the monsoon flow will strengthen thereafter, likely leading to its advancement up to northwest India.

LATE IN KOLKATA
In this manner, the remaining parts of central and east India are expected to be covered by the end of first week of July and the entire country by the middle of July.
Tracing back the progress of the rains, the IMD said the monsoon set in over Kerala on May 31 and reached Mumbai on 11 June, both very near to the normal dates.
It managed to cover the northeastern states slightly earlier than the normal time, but reached Kolkata only on June 13, about a week later than normal.
As of Tuesday, the monsoon has reached up to central and east India. Good rainfall activity is being reported from most of the areas covered, too, but there has not been any advance of the monsoon over new areas since June 18.
Further progress is halted mainly due to non-formation of a monsoon low pressure area/depressions over the Bay of Bengal.
Strong northwesterly flows prevailing over most parts of northwest and adjoining central India and frequent western disturbances have upset the monsoon rhythm, inhibiting its advance over the remaining parts of the country.

WESTERN DISTURBANCE
On Tuesday, an inbound western disturbance persisted over north Pakistan and neighbourhood on Tuesday.
It is expected to affect the western Himalayas and plains of northwest India during next 2-3 days.
Due to the weak Bay of Bengal branch of monsoon, there is some delay in advance over northern parts of Madhya Pradesh, western parts of Bihar and most parts of Uttar Pradesh and Uttarkhand, the IMD said.
Meanwhile, a few international models predicted the formation of a cyclonic circulation/low-pressure area over west-central Bay of Bengal around Thursday.
While this may not help the cause of monsoon progress into areas not covered as on date, another round of peninsular rains may be in the offing.
A ‘low' taking shape near the head Bay of Bengal is the most ideal scenario that can help drive the monsoon current west-northwest into northwest India.
The 24 hours ending Tuesday morning saw widespread rainfall being reported from Assam and Meghalaya in the northeast and fairly widespread over the west coast.

NORTHERN LIMIT
The northern limit of monsoon continued to pass through Rajkot, Ahmedabad, Indore, Seoni, Pendra, Ambikapur, Daltonganj, Gaya, Muzaffarpur and Raxaul, an alignment reached more than a week ago. Satellite imagery showed convective (rain-generating) clouds over parts of Assam, Meghalaya, southeast Arabian Sea, southeast Bay of Bengal and Andaman Sea.
The IMD has forecast isolated heavy to very heavy rainfall over sub-Himalayan West Bengal, Sikkim, Arunachal Pradesh, Assam, Meghalaya, Nagaland, Manipur, Mizoram and Tripura during the next two days.
An outlook until Sunday spoke about the possibility of fairly widespread rainfall activity over east and northeast India and along west coast. Isolated heavy falls are also likely at these places during this period, the IMD said.