European Centre for Medium-Range Weather Forecasts indicates in an extended outlook that heavy rain may lift from most of North-West and East India except the Himalayan foothills and parts of Central India and West Coast by July 26.
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Heavy to very heavy rainfall is likely to continue over Central and adjoining North-West India during next 4-5 days, with a west-to-east-bound Madden-Julian Oscillation (MJO) wave being found to boosting convective activity (cloud-building and rainfall) over the Bay of Bengal region for the first time during this monsoon for the week from July 10 to 16.
The MJO wave is a band lower pressure packing clouds, moisture and rainfall periodically circumnavigating the global tropics, and periodically crosses the higher levels of the atmosphere over the Indian Ocean. It significantly influences weather patterns, including rainfall, wind and pressure under its footprint and is known to precipitate monsoon onsets and low-pressure areas.
MJO help to the fore
A low-pressure area is located lay over south Jharkhand, with backbone monsoon trough running near its normal position from Bikaner, Deomali, Hamirpur, Daltonganj, Jamshedpur and Digha and thence south-eastwards to north-east Bay of Bengal. This alignment, if it were to sustain, might help scoop up another circulation/’low’ in the north-east Bay sooner than later.
Numerical model predictions of India Meteorological Department (IMD), however, indicates formation of the ‘low’ over land over the North-Eastern States with proximity to north-east Bay by July 21. This could likely cause the monsoon trough to move further north along the foothills of the Himalayas, though this needs to be verified with conditions obtaining towards end-July.
Rain belt hills-bound?
This could potentially ‘monsoon break’-like conditions, in which rain belt moves entirely to the foothills and adjoining plains. Heavy rain may lift from Central India and North-West India, and largely shut out from the West Coast and Peninsular India. Simultaneously, rainfall may pick up over North-Eastern States, coastal Andhra Pradesh and Tamil Nadu by July-end.
An extended outlook for the week July 17 to 23 of the IMD said monsoon trough may lie north of its normal position during first half of the week, and shift gradually towards its normal position thereafter. The offshore trough along the West Coast, strength of which along with that of the monsoon trough decides health of the monsoon, would be feeble for some days of the week.
Rain for North India
Therefore, ahead of the potential movement of trough towards the foothills, fairly widespread to widespread rainfall and isolated heavy falls will continue over many parts of North-West India and with isolated heavy to very heavy falls over Central India. Fairly widespread to widespread rainfall with isolated heavy falls is also likely along West Coast during most days during July 17 to 23.
Overall, the IMD projected near normal to above normal rainfall activity for Central India; near normal over most parts of North-West and South Peninsula; and below-normal rainfall over most parts of East and North-East India. This follows a likely second consecutive week of excess to large excess rainfall over Central and adjoining North-West India during July.
Cumulative rain trends
Weekly cumulative rainfall departures have exceeded 100 per cent for east Madhya Pradesh (199 per cent), Saurashtra and Kutch (150 per cent), Vidarbha (130 per cent), west Rajasthan (106 per cent) and Chhattisgarh (100 per cent) after some of these areas faced deficits initially. All-India weekly cumulative rainfall in was 26 per cent above average during the week ending July 9.
On Friday, the monsoon continued to be strong over the northern half of the country with a trough other than the monsoon trough running from south-west Uttar Pradesh to the ‘low’ over south Jharkhand. Yet another trough was draped across from north-east Arabian Sea to the same ‘low’. Cyclonic circulations hovered over north-east Assam while a western disturbance has rolled in with its axis lying nearly across the Chandigarh, potentially raising rainfall generating capacity over the region.
Published on July 11, 2025