January and February are the rainiest winter months for the plains of North and East India. While, the northern plains have received, at least consolatory showers on one or two occasions, the eastern parts have remained completely dry. Punjab, Haryana, Rajasthan and Delhi have received normal rains, so far in the first half of January. However, the eastern states of Bihar, Jharkhand and West Bengal have remained completely dry. It seems like a repeat of last year when Bihar remained largely dry and Jharkhand below normal in the month of January. Saving grace was West Bengal which recorded normal rains.
The eastern states are unlikely to have any good rainy spells in the second half of January, as well. Like, the rains had caught up well in the month of February last year, it could be a repeat of the same, but no assurance as of now. Between 01st January and 15th January 2025, all three states are either without rain or have a very large seasonal deficit.
The reasons for poor rains over these states could be attributed to a lack of western disturbances and their induced systems. So far, the westerly systems have limited their influence to the northern plains and have not penetrated beyond Uttar Pradesh and Madhya Pradesh. Even, East Uttar Pradesh and the entire Madhya Pradesh have large seasonal shortfalls.
There is a western disturbance likely to cause scattered rains today and tomorrow but it will not reach beyond central Uttar Pradesh. The next spell of rain for the northern plains will be stronger and longer between the 20th and 23rd Jan. However, like the last one, even the remnants of the system will not reach the eastern parts. The anticyclone over the central parts is blocking the entry of weather systems for the eastern region. Not only, the eastern states of Bihar, Jharkhand and West Bengal will remain dry, the entire Northeast India will have similar conditions. The seasonal deficit is expected to increase for the eastern and northeastern parts in the remaining days of January 2025.