The March natural gas contract experienced significant movement during its last day of trading, settling up 1.3 cents at $3.427/mmBtu.  This was its highest price since January 25th.  Updated weather forecasts calling for colder-than-normal temperatures into early March lead to three days of price gains, as the winter-season contract expired.  The April contract, however, settled down 1.4 cents, at $3.456/mmBtu.