weather-driven market; weather-dependent market
A financial market whose price movements are heavily influenced by weather conditions, such as agricultural commodities or energy futures.
This year's wheat market was weather-driven and fluctuated greatly due to the drought.
In weather-dependent markets, weather forecasts become a key factor in investment decisions.
相場 is a general term for market price or market conditions, while 天候相場 specifically refers to a market driven by weather factors.
Compound of 天候 (weather) and 相場 (market price). The term likely originated in commodity trading contexts where weather directly impacts supply and demand.