The April natural gas contract settled at $3.976 per mmBtu, its highest expiration in 18 months.  The lingering winter weather and a couple of bullish storage reports propelled this market higher throughout March.  This higher pricing has attracted a significant number of speculators to the market and there has been a rapid increase in trading activity around NYMEX natural gas.  The market, however, continues to provide some resistance around the $4 mark and with mild temperatures approaching, it may limit the potential upside for natural gas.