Tuesday, June 22, 2010

10-day lag seen in June rains, may not hit sowing

A 10-day outlook for monsoon suggests that seasonal rains might just make it to Bihar and eastern Uttar Pradesh, but only with a lag of as many days.
“The normal date for onset over east Uttar Pradesh is June 18, which means that the monsoon caravan is already late by three days,” said Dr Akhilesh Gupta, leading operational forecaster and Advisor to the Ministry of Science and Technology.

And there is no possibility of this delay being made up if initial conditions as obtaining on Monday are any indication, Dr Gupta told Business Line on Monday. This would mean that June would end up with a cumulative delay of eight to 10 days before monsoon rains can reach parts of northwest India beyond east Uttar Pradesh.
Crucially enough, the delay is not seen as pausing a major threat to sowing operations despite the crop (rice, pulses, oilseeds and maize) being largely rain-fed. This is because the transplanting operations in the region are usually taken up between the first week and third week of July only. Rains falling during the intervening period, though, are a blessing for the nurseries.
By the same token, the monsoon may not reach west Uttar Pradesh until July 1, done in by the ‘lag effect.' The big difference is that west Uttar Pradesh is entirely irrigated, and is in a position to cope with the likely delay in onset of monsoon.

According to Dr Gupta, forecast beyond a 10-day period is fraught with risk and it may not be fair to comment on how things would pan out during the rest of July.
For now, however, forecasts indicate a reasonably strong revival of monsoon from Wednesday/Thursday. This active phase may last the whole of the next 10-day period.
A reviving monsoon approaches the mainland always from the south, and triggers activity over the Bay of Bengal as well. Thus, the new monsoon pulse would cover Kerala, Karnataka, Tamil Nadu and parts of Andhra Pradesh before hitting Konkan and the rest of the west coast in phases.
By Saturday, there is a possibility that some kind of a circulation may show up over the Andhra Pradesh coast, which may move inland.
This would bring rains over the north peninsula and central India. Some rains are also likely over Bihar and Uttar Pradesh from a weak interaction of the Bay system with an incoming western disturbance.

It may not bring the monsoon into the northwest, but it would lead to abatement of the severe heat wave conditions in the region.
India Meteorological Department (IMD) said on Monday that heat wave to severe heat wave conditions were prevailing over Rajasthan, Delhi and parts of Haryana.
Heat wave conditions were also reported from many parts of west Uttar Pradesh, northwest Madhya Pradesh and isolated pockets of Gujarat region and Jammu. The highest maximum temperature of 48.1 deg Celsius was recorded at Sri Ganganagar in Rajasthan during the 24 hours ending Monday morning. The heat wave is being anchored by a seasonal trough over northwest India (northwest to southeast), which is aligned slightly north of its normal position.
The northward bias brings a barrage of hot northwesterlies into play over the region, crowding out cooler easterlies from the Bay of Bengal. This is what sustains the heat wave.
But from Thursday onwards, the brewing system in the Bay would allow the easterlies to start filling the plains of the northwest. The resulting cloudiness would gradually help cap the heat.
By July 1, the entire north-west India, except west Rajasthan, would see the heat abate completely as cool easterlies make headway as far northwest as Punjab.
Meanwhile, India Meteorological Department (IMD) sees renewed wet spell along the west coast during the next two days in what is projected as a revival of monsoon.
Seasonal rains had gone into a lull over the last week, delaying the progress of the monsoon into east and east-central India. Fairly widespread rain or thundershowers have been forecast over Konkan, Goa, coastal Karnataka, Andaman and Nicobar Islands, Kerala and Lakshadweep during next 24 hours and may scale up thereafter.
A warning valid for the next two days said that isolated heavy to very heavy rainfall may unfold over Assam, Meghalaya, and Arunachal Pradesh. Heavy rainfall is likely over Nagaland, Manipur, Mizoram, Tripura, Konkan, Goa and coastal Karnataka during this period.
Widespread rainfall activity has been forecast over the west coast during the four to five days. Fairly widespread to widespread rainfall will occur over the Northeastern States while being scattered to fairly widespread central and east India and the rest of peninsular India and Maharashtra.

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