Fire-affected areas around Tenterfield and Armidale are set to receive the most rain with a high chance of anywhere between 13mm and 35mm predicted for the two towns on Friday and Saturday.

While the rainfall will help firefighters tackle the blazes around Northern NSW, Bureau of Meteorology's Jordan Notara said people in areas where fires are burning still need to be extra careful.

"Lightning does not always come under the rain core itself. So there could be some dry lightning strikes that could potentially starting fires. It's a double-edged sword," the meteorologist said.

"Gusty winds could drop some trees and cut off access ways to fire grounds and vehicles could get stuck in mud."

It won't be as heavy in Gunnedah but there is some rain expected. If it's going to come, it looks like Friday will be the most likely with an 80 per cent chance of 4-8mm.

The maximum temperature in Gunnedah is set to hover around the low to mid 20s until Tuesday when 31 degrees is predicted.