Commodity Seasonality: Oil, Gas, Agriculture

Commodity seasonality is the one form of seasonality with a physical cause. Grains are harvested in autumn, gas is injected in summer and withdrawn in winter, and gasoline demand peaks during the driving season. The calendar is the supply-demand curve.

Unlike stocks or FX, commodities have seasonality rooted in weather, agriculture, and the human calendar of heating and travel. That makes the patterns more robust — and easier to explain.

Crude oil and gasoline

Window	Seasonal driver
Feb–May	Refinery maintenance; gasoline build for summer
Memorial Day–Labor Day	US "driving season" — peak gasoline demand
Sep–Oct	Demand fades; inventories build
Dec–Feb	Heating oil demand; winter weather risk premium

The summer driving season is the single most cited oil seasonal. Gasoline crack spreads (refining margin) often widen into late spring as refiners ramp up ahead of peak demand.

Natural gas

Natural gas has the cleanest seasonal cycle in commodities:

• Injection season (Apr–Oct): storage fills for winter; prices often pressured if storage is healthy
• Withdrawal season (Nov–Mar): storage draws; cold snaps spike demand and price
• Hurricane season (Jun–Nov): Gulf production risk; spikes on disruption

Winter gas is the classic weather trade: cold winters lift prices violently, mild winters crush them. Volatility is highest in the withdrawal season.

Agriculture

The US grain cycle drives corn, soybeans, and wheat:

Phase	Months	Risk
Planting	Apr–May	Wet/cold delays cut acreage
Pollination	Jun–Jul	Heat/drought cuts yield
Harvest	Sep–Nov	Frost/wet delays cut supply
Off-season	Dec–Mar	South American crop takes over

"Rain makes grain." Summer weather scares move grain prices more than any other factor. The pollination window is when crops are most vulnerable and prices most reactive.

Heating oil

Distillate (heating oil/diesel) demand peaks in winter, especially in cold northern climates. Winter weather risk premia build into heating oil and natural gas into late autumn.

Gold (demand-side seasonality)

Gold's price has a documented demand seasonal:

• Indian wedding season (Oct–Dec): physical jewelry demand
• Diwali: a major gold-buying festival
• Chinese New Year (Jan/Feb): gift and investment demand
• Year-end: Western investment flows

Physical demand doesn't always move price — but it biases gold's seasonal tendency positive into late autumn/winter.

Why commodity seasonality is stronger

• Physical storage costs make timing matter — you can't hold grain forever
• Weather is cyclical by definition
• Inelastic short-term demand (you heat your house regardless of price)
• Supply is fixed within a season (harvest happens when it happens)

How to use it

1. Match the trade to the season: long gas into winter risk, not summer
2. Watch weather, not just calendar: a forecast can override the seasonal
3. Use spreads: crack spreads (oil vs products) and calendar spreads trade the seasonal directly
4. Size for volatility: seasonal spikes are sharp; risk grows into them
5. Beware inventory reports: EIA and USDA reports can break a seasonal pattern in one print

Practical steps

1. Note the injection/withdrawal season for gas on your calendar
2. Track US driving season and gasoline inventories
3. Watch grain pollination weather in Jun–Jul
4. Layer Indian and Chinese festival demand onto gold's calendar
5. Trade seasonal spreads where possible — they isolate the calendar effect

Bottom line

Commodity seasonality is real because it is physical. The calendar is the supply-demand curve. Trade with the harvest, the heating season, and the driving season — and respect the weather that can override all three.