Natural Gas Seasonal Spread

A calendar spread involves simultaneously buying one contract month and selling another (e.g., Buy March, Sell April). You profit from the change in price DIFFERENCE between months, not absolute price direction. This reduces directional risk.

Natural gas demand is heavily weather-dependent. Winter heating demand and summer cooling demand (power generation) create predictable seasonal cycles. The injection season (April-October) and withdrawal season (November-March) affect storage and prices cyclically.

The March/April (H/J) spread is nicknamed 'Widow Maker' due to its extreme volatility. It can move $1-2+ during late winter as the market transitions from heating season to injection season. Weather uncertainty makes it particularly dangerous.

Spread margin is reduced (20-50% of outright) because the long and short legs partially offset each other. If prices move up or down, both legs move somewhat together, reducing net exposure compared to an outright position.

Use a spread order (single order for both legs) rather than legging in separately. This guarantees your spread price. Most futures platforms offer spread order types. Specify 'Buy X/Sell Y' or 'Sell X/Buy Y' and your target spread price.

Typical entry window for short H/J is January 15 to February 15. This captures the winter-to-spring transition. Enter when spread is wider than historical average for that date. Exit by late February or before March contract expiry.

Storage levels adjust seasonal patterns. Below-average storage supports winter premium (H/J may stay wider). Above-average storage weakens winter premium (H/J may narrow more easily). Always compare current storage to 5-year average before trading.

Pattern reliability is the percentage of historical years where the seasonal pattern worked (e.g., 8/10 = 80%). Higher reliability suggests more confidence. Require 70%+ reliability before trading a pattern. Also note the worst-case year to size stops.

Roll 5-10 days before expiry when liquidity is still good. Use calendar roll spread orders if available. Factor roll costs into your strategy. For longer seasonal patterns requiring multiple rolls, plan and budget for roll costs upfront.

Reduce size or skip. If seasonal pattern says 'short H/J' but storage is very low and cold weather forecast, the pattern may fail. Full size only when fundamentals are neutral or supportive. 50% size when fundamentals slightly oppose.

Buy call on one month, put on other to create synthetic spread with defined risk. For short H/J: Buy March put + Buy April call. Maximum loss = combined premium. This protects against extreme events like polar vortex that could blow through futures stops.

US LNG exports create new patterns. Asian winter demand pulls US gas in winter (additional support). Summer exports are more moderate. Henry Hub now correlates more with global gas (TTF, JKM). Traditional seasonal patterns have shifted - always test recent years.

Walk-forward testing optimizes parameters on past data (in-sample), then tests on subsequent data (out-of-sample). Roll forward and repeat. This validates that patterns persist rather than being data-mined artifacts. Essential for seasonal strategy development.

Consider: (1) Pattern reliability - higher = more weight, (2) Expected reward - higher = more weight, (3) Correlation - lower correlation between spreads = more diversification benefit. Use mean-variance or risk parity approaches. Total allocation 15-25% of commodities capital.

Trading relative value between commodities based on seasonality. Example: Natural Gas vs Heating Oil ratio has seasonal patterns (HO favored in winter for direct heating, NG may be favored in summer for power). Provides diversification from pure NG spreads.