NEW DELHI: With temperatures remaining above normal since November, this winter could well be the warmest ever recorded not only in North India, but across the country. India Meteorological Department (IMD) director general Laxman Singh Rathore said Januray too saw above normal temperatures and the trend is likely to continue in February.Meteorologists have attributed a warmer winter to El-Nino. The phenomenon is associated with warming of waters of the Pacific Ocean. El-Nino also had an adverse effect on the Southwest Monsoon, which was "deficient" for the second consecutive year."Weather stations across the country have recorded above normal temperatures this winter. January was definitely the warmest not only in North India, but also across the country as per the temperatures recorded in different weather stations. The phenomenon will also continue in February."Also, duration of day will increase gradually and this will lead to rise in radiation, which will affect the temperature level," Rathore said.However, final conclusion can only be drawn by the end of the season.The last week of December and January are considered as the coldest times when the winter reaches its peak.Incidentally, 2015 was the hottest year on record. The hot temperatures last year were also observed in November and December and continued in January this year as well.Although a global phenomenon like the El-Nino was a major factor, local factors also played a major role in keeping the mercury above normal.For instance, an anticyclone kept the temperatures above normal in parts of Central and North India. An 'anticyclone' is opposite to a cyclone in which winds move into a low-pressure area. In an anticyclone, winds move out from a high-pressure area with wind direction clockwise in the northern hemisphere and anti-clockwise in the southern hemisphere.On the other hand, there was a some dip in temperatures in January due to two Western Disturbances.