The average temperatures for New Orleans in mid-March are 72F/22C for the high and 53F/12C for the low. Record highs and lows during this period are 87F/30C and 31F/0C, respectively. Heavy rain is possible any time of the year, so bring raingear or a travel umbrella. (March is not hurricane season, by the way.) Needless to say, if you are going to do any walking around in the city, bring comfortable shoes.