This follows reversal of an earlier order by the district magistrate who had ordered the closure of all schools up to class 12th till Jan 22.
However, classes from 1st to 5th will remain closed for another two days and will reopen Wednesday.
The maximum temperature in the state capital Sunday was 21.7 degrees Celsius, while the minimum temperature was 8.6 degrees Celsius, two notches above the season's normal temperature. The humidity remained at 95 percent.
The Met officials, however, warned that it may be little early to wrap up the winter clothes as a low pressure depression forming over Rajasthan might herald the return of the winter chill in coming days.
"There might be some rain and thunder storm in the weekend," the official said.
Meanwhile, over two dozen trains continued to be running late in the Northern Railway and the North Eastern Railway divisions.
Trains like Kota-Patna Express, Kaifiyat Express, Swarna Shatabdi, Farakka Express, Gorakhdham Express, Amrapali Express and Upasana Express were running late by several hours.
The 6E-444/445 flights between Delhi-Lucknow, Lucknow-Mumbai of the Indigo Airlines will continue to be suspended till Jan 26.
"A final review after the weather conditions improve will decide the future course of these flights," an airport official said.