In both these months the atmospheric conditions vary over the Indian sub-continent.In the month of January it is the dry winter season .During this period a high pressure region develops in north-western India due to the southward movement of the sun.The average temperature in North during this period is about 10 degree where as In south it is about 25 degrees.
In the month of June it is the summer season over the Indian sub-continent .During this period the sun moves northward and the temperature increase.The temperature is about 49 degree in Rajasthan,38-40 degree in Bihar etc.