New Delhi, Monday June 2
5 The monsoon has remained stuck during the past forty eight hours even as expected funneling of moisture into north India via a trough formation along the Gangetic plains did not materialize. The moisture influx was not established due to poor interaction between the trough and a cyclonic circulation over West Bengal and adjoining Jharkhand that was supposed to be the driver.
Troughs are places where winds from opposing directions meet (or winds turn) and atmospheric pressure is low while the turbulence caused by such interaction (or turning) leads to rain, thundershowers and storms.
The Northern Limit of Monsoon (NLM) continues to pass through Veraval, Navasari, Malegaon, Betul, Jabalpur, Siddhi, Varanasi and Gorakhpur. The northern limit of monsoon is an imaginary line that connects places where the monsoon has reached at a given point in time.
A north-south trough extends from sub-Himalayan West Bengal to north Bay of Bengal and would lead to the enhancement of rainfall over sub-Himalayan West Bengal and northeast India but monsoon activity would remain subdued over Gangetic West Bengal.
A cyclonic circulation over central parts of Uttar Pradesh persists. The weather system along with the interaction of southeasterly winds along the Himalayan foothills would usher in rains during the next twenty four to forty eight hours in the region. Bihar and Jharkhand would receive isolated thundershowers.
A southwesterly surge seems strengthening between Konkan and north coastal Maharashtra and is a positive sign for increased rainfall in the region. Good showers are expected along the area over the next couple of days. Mumbai falling in the region would also witness build in rainfall activity. But the rest of west coast would continue with light to isolated moderate falls.
Another trough from Telangana to coastal Tamil Nadu has come into formation. The trough is mostly devoid of moisture and is unlikely to cause any significant affect over the area. Though north coastal Andhra Pradesh and north coastal Tamil Nadu may expect light rain. A few moderate showers are predicted for north coastal Andhra.
Some residual moisture prevailing in central India would continue light rain. The moisture levels have increased over Gujarat, Rajasthan, Punjab and Haryana due to penetration of moist southwesterly winds.
Marginal drop in day temperatures is possible over the northwest plains under mainly clear days and isolated thundery activity towards evening or early morning due to the presence of a Western Disturbance over Jammu & Kashmir.
Western Disturbances are westerly (traveling west to east) weather systems that originate due to evaporation over the Mediterranean or the Caspian Seas.
