Frodo's visions at Amon Hen

[The Might]

As always, I find posting the discussed paragraph is useful:

But everywhere he looked he saw the signs of war. The Misty Mountains were crawling like anthills: orcs were issuing out of a thousand holes. Under the boughs of Mirkwood there was deadly strife of Elves and Men and fell beasts. The land of the Beornings was aflame; a cloud was over Moria; smoke rose on the borders of Lórien. Horsemen were galloping on the grass of Rohan; wolves poured from Isengard. From the havens of Harad ships of war put out to sea; and out of the East Men were moving endlessly: swordsmen, spearmen, bowmen upon horses, chariots of chieftains and laden wains. All the power of the Dark Lord was in motion.

At first I thought that there might be some future references, but now I have to agree with Legate, there are no clear examples.
Wolves pouring from Isengard and horsemen galloping in Rohan also fits, the First Battle of the Fords of the Isen had taken place the day before so there would still be much going on there.