This change in weather can be attributed to the series of cyclonic circulations prevailing over the region. A cyclonic circulation is persisting over Northwest Rajasthan and adjoining Punjab, while the other circulation is seen over North Bangladesh and adjoining West Bengal. The third one is marked over North Jharkhand and adjoining areas.
Due to instability in atmosphere, winds have become very light across northern and Indo-Gangetic plains. These systems have also led to significant rise in levels of humidity.
All these factors have also marked the comeback of moderate to dense fog over entire region during the last 24 to 48 hours, especially over East Uttar Pradesh and Bihar. This persistent fog cover is here to stay, which in turn will not let the day maximums rise much.
With this, cold day conditions are likely over several parts of Uttar Pradesh and few pockets of Bihar, Rajasthan, Punjab, Haryana and Delhi. Cold day conditions are declared when day maximums are equal or below 16°C.
Not only this, increased moisture levels may also result in some rain and thundershowers in Jharkhand, Bihar and West Bengal by Sunday evening. This will lead to further drop in maximums temperatures.
Image credit: Indian Express
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