After a comparatively clear day, fog once again blinded Delhi on Friday.

The minimum temperature went down by about 3° Celsius to 8.7° C, a meteorological department official said.

The minimum visibility in Palam area, where the airport is located, was less than 25 metres early morning, delaying almost all early flights, airport sources said.

Railway services continued to be badly affected due to foggy conditions over the northern plains.

Five trains have been cancelled in the past two days and some cancellations are likely on Friday also, Northern Railway sources said.