In the wake of Western Disturbances coming from the Tibet region, the conditions became favorable for the occurrence of very dense fog layer. The regions witnessing this weather condition are the foothills of Himalayas over northern Uttar Pradesh, east Uttar Pradesh, Bihar, Sub Himalayan West Bengal, Sikkim and Assam. According to Skymet weather, due to the effect of western disturbance in the western Himalayas,there is a presence of anti cyclonic winds in the north eastern parts of Rajasthan in the lower levels.
Due to these weather activities, northwesterly-northerly winds are affecting East Uttar Pradesh and Bihar. These factors are also facilitating the formation of fog in East Uttar Pradesh and parts of Bihar.
This very dense fog layer, prolonged during the day time. This caused the day temperatures to decrease significantly. The temperature prevailed between 17 degree celsius to 20 degree celsius over these areas. While night temperatures, remained between 9 degree to 11 degree. The night temperatures are slightly above normal due to fog layer, while day temperatures are below normal.
This temperature is likely to remain the same during the next 2 to 3 days, as the layer of fog mentioned above will persist. Gradually, the day temperature will start rising from North west parts of UP to eastern parts of the country.