The ZEMA graph shows the North American natural gas spot prices on NYMEX for Henry Hub, Transco Zone 6, PG&E Citygate, and Chicago Citygates for December 2015. Units are in USD/MMBtu.
There was nothing unusual in the natural gas prices behavior with the arrival of winter. Prices continues climbing up throughout the month on all hubs. Transco 6, however experienced some relief in the middle of the month with prices dropping below 4 USD/MMBtu. This trend, however was interrupted in the last days of the year with the prices skyrocketing above 6 USD/MMBtu.
Data Sources: CME, NYMEX