Delhi Goes Colder Than Average During First Half Of November, Second Half Same Track Likely

Delhi has recorded below normal temperature on daily basis for the last one week.  Mercury remained below normal by 3-4°C and the lowest temperature of this season was  measured at 9.6°C on 17^th November.  This, also is the first record of under 10°C minimum for the national capital in this season. Some other locations like Ayanagar hovered around 9°C, nearly amounting to mild cold wave conditions.

As per the pentad normal, Delhi starts with a minimum of 15°C in November and ends with 11°C in the last days.  The mean minimum temperature for the month is 12.9°C.  Expectedly, the 1^st half of November is warmer by about 2°C than the 2^nd one. The 2 halves have average minimum temperature of 14.3°C and 11.7°C respectively. This year, the 1^st half has been averaged out at 13.3°C, about 1°C lower than the mean temperature.

The prevailing La Nina conditions have been impacting the temperature profile of North India in general and also Delhi in particular. This is in line with the expected  below normal temperature during the fall of year and likely to find extension during winter season 2022.  Last year also, La Nina conditions swept across the region, albeit a bit stronger than this year. 

October 2020 was the coldest in 58 years, with the mean minimum temperature of 17.2°C  against the normal of 19.1°C. Even, November 2020 was the coldest in the last 71years by clocking a monthly average of 10.2°C against the long period average of 12.9°C.  

Also, 23^rdNovember 2020 was the coldest day since 2003, as it recorded a minimum temperature of 6.3°C, about 6°C below the normal amounting to severe cold wave conditions. The mean minimum temperature of Delhi for November was 12.8°C, 13.4°C and 15°C in 2016 & 2017, 2018 and 2019 respectively. Last year, the minimum temperatures  persistently remained about 10°C or less  during 2^nd half of November.

A weak western disturbance is moving across extreme northern parts of Jammu and Kashmir and Ladakh region.  Consequentially, a small scale dry cyclonic circulation has formed over Delhi and neighborhood. This has resulted change in the pattern to largely easterly wind in the lower levels.

Accordingly, the minimum temperature has risen marginally and it is likely to hover around 11-12°C for the next 48hr. Following clearance of the western disturbance, the night temperatures will fall again from 21^stNovember onward. These are likely to dip to single digit between 22^nd and 24^th November, below normal by about 3°C.  

Delhiites can expect chilly and hazy mornings and pleasantly warm sunny days. Strong surface winds are expected after 20^th November causing nip in the air.  No rainfall is likely during the remaining days of November.