March natural gas prices managed to build on Tuesday afternoon's strength early this morning, but they remain trapped inside of a tight trading range. While key demand areas of the US currently experience severe weather conditions, ideas that the longer range weather maps (11 to 15 day) indicate a slightly warmer trend, appears to be keeping gains limited. Meanwhile, cash natural gas prices in Canada were higher for the second straight session on increased demand from cold weather. Near term weather maps remain cold into the weekend and then begin their slight warming trend.