Weather experts have cited weather systems like formation of north-south trough and moisture incursion over the Bay of Bengal are the reasons behind the alarmingly high amount of rainfall that the Northeast has been receiving for the past couple of days.
According to weather experts, formation of a north-south trough roughly along longitude 89 degree East to the north of latitude 22 degree North between 2.1 and 3.1 km above mean sea level is a factor leading to the heavy rainfall in the northeastern region.
Meanwhile, moisture incursion from the Bay of Bengal is also likely to continue over the Northeast due to strong lower-level Southerly/Southwesterly winds from May 16-19.
“The northeastern states have definitely received a surplus of pre-monsoon showers this time. Rains occur as a result of different weather systems and these systems differ at different times,” said Sanjay O’Neil Shaw, senior scientist of the Regional Meteorological Centre (RMC), Guwahati.
“The east-west trough from west Uttar Pradesh to Jharkhand now runs from north-east Rajasthan to western Assam over south Uttar Pradesh, south Bihar and sub-Himalayan West Bengal at 0.9 kms above sea level,” Shaw said
Similarly, the north-south trough along longitude 89 degree East to the north of latitude 22 degree North at 1.5-2.5 kms above mean sea level, which is why we can expect moderate to very heavy rainfall at isolated places over the northeastern state during the next four days,” he added.
Under the impact of these weather systems widespread to fairly widespread rainfall accompanied with heavy to very heavy showers are likely to occur at isolated places over Arunachal Pradesh on Tuesday. Heavy rainfall has been predicted at isolated places in the state on May 18-19.
Meanwhile, thunderstorms accompanied by lightening and heavy to very heavy rainfall is likely to occur at isolated places of Assam on Tuesday and May 18, while heavy rainfall may occur in isolated places of the state on May 19-20.
In Meghalaya, accompanied by lightening and heavy to extremely heavy rainfall is likely to occur at isolated places on Tuesday and May 18, while heavy to very heavy rainfall may occur in isolated places of the state on May 19-20.
Weathermen have also predicted thunderstorms together with lightening and heavy rainfall to occur at isolated places over Nagaland, Manipur, Mizoram and Tripura on Tuesday and May 18.