Severe winds with the potential to blow down marquees have been predicted to cross the city during Melbourne Cup festivities.

Authorities have warned revellers to take precautions as forecast squally conditions become more serious.

The Bureau of Meteorology earlier predicted a cold, gusty change to pass through Melbourne about 5pm.

But Emergency Management Commissioner Craig Lapsley said on Tuesday morning damaging winds with peak gusts of up to 100km/h were now predicted for the Melbourne area.

“People celebrating the race that stops a nation need to take care to prevent accidents or tragedies,” Mr Lapsley said.

The change will be caused by a low-pressure trough moving through Victoria from the west.

It is expected to reach Geelong and Melbourne between 4pm and 5pm.

Mr Lapsley said damaging winds between 65km/h and 75km/h with peak gusts between 90km/h and 100km/h have been forecast for parts of the Central district, which includes metropolitan Melbourne.

The warning comes after Country Fire Authority chief officer Euan Ferguson declared the first total fire ban of the 2014-15 fire season for the Mallee district.

“In addition to a total fire ban in the Mallee region today, severe blustery winds are expected across Melbourne and central Victoria late this afternoon which have the potential to blow down marquees and other temporary structures,” Mr Lapsley said.

The State Emergency Service has advised people to move vehicles under cover or away from trees, secure loose items and keep clear of fallen power lines.

This story first appeared in The Age