Mars will be exceptionally bright for sure at this perihelic opposition, especially to these unfamiliar with it. However, the magnitude is not affected by dust. What may be affected however is the naked eye colour which becomes more yellowish. This effect was seen in 1909, 1924, 1956, 1971, 1973 and 2001 and 2007. There are some notes for observing Mars in 2018 on the BAA website. And the latest images and info on the progress of the dust storm can be seen here.