Most of New South Wales is under a total fire ban today with severe fire danger due to very hot and dry winds. Sixteen out of twenty one fire districts in NSW are under a total fire ban today with the only districts not under a fire ban in the northeast and far west. From the Hunter to the Far South Coast and west to the Southern Riverina all districts are likely to reach severe fire danger ratings. The Alpine Monaro fire district is set to be even more dangerous and reach an extreme rating. These dangerous fire conditions will make firefighters work hard to contain the many fires already burning in NSW as well as working to put out new fires that are likely to develop today with the dry heat. The reason why conditions are so dangerous in NSW today is because of a very hot airmass that is being dragged into NSW by west to northwesterly winds. Temperatures will rise into the 40's in many areas with the dry and windy conditions also contributing to the fire danger. Another factor that will make fire fighting difficult is that a southerly wind change will move through the state from this afternoon and will reach the north tomorrow. Wind changes mean that fires change direction and create a new fire front. Thankfully for firefighters temperatures will drop significantly behind the southerly change with temperatures this hot unlikely for at least the next fortnight. Winds will also be light to moderate for the next few days. Unfortunately thunderstorms may spark a few more fires over coming days, but significant falls from these storms could put many fires out.