Rallies in thermal coal and Brent crude oil of around 11% and 12%, respectively, were partly offset by a fall in aluminum of almost 8% and a smaller decline of around 1% in gold, Westpac Banking (ASX:WBC, NZE:WBC) said in its July commodity forecast on Monday.

Volatility in the markets eased somewhat over the past month as the risk of extreme tariff scenarios receded as the US government's July 9 deadline drew closer.

However, the US announced a 50% tariff on copper imports, leading COMEX futures to rally to be up 13%. The Westpac Commodity Export Price Index was flat through the month.

The financial services firm predicts gold prices to rise to a high point of $3,370 per ounce in the March 2026 quarter, before declining to $3,260 per ounce by the December 2026 quarter.

The aluminum price is forecast to rise to $2,830 per tonne in December and March 2026 quarters, before dipping slightly and then climbing to $2,900 per tonne in the March 2027 quarter, and rising to $3,000 per tonne in the September 2027 quarter. The price of copper is expected to reach $9,760 per tonne in the September quarter, and then to fall to $9,250 per tonne by the September 2026 quarter. It is then expected to rise to $10,950 per tonne in the June 2029 quarter.

The prices of nickel and lead are expected to fall to a low point of $14,200 per tonne and $1,910 per tonne, respectively, in the June 2026 quarter, before rising again. Westpac expects the zinc price to fall to a low of $2,600 per tonne in the March 2026 quarter, before rising to $2,900 per tonne in the June 2029 quarter.

It forecast Brent crude oil to fall to $67 per barrel in the September quarter, and then to $60 per barrel in the December quarter. It is then forecast to rise in the succeeding quarters to $75 per barrel by the June 2029 quarter.