1) Rain clouds were looming on the horizon.

2) The sun appeared on the horizon.

3) The town was just a blur on the horizon.

4) We discerned a sail on the horizon.

5) We could see a ship on the horizon.

6) Dark storm clouds loomed on the horizon.

7) A ship appeared on the horizon.

8) Do you think those are rain clouds on the horizon?

9) A grey smudge appeared on the horizon. That must be Calais,[http://sentencedict.com/on the horizon.html] thought Fay.

10) The helicopters appeared as two black dots on the horizon.

11) She trained her binoculars on the horizon.

12) A dark bank of cloud loomed on the horizon.

13) An economic crisis is looming on the horizon .

14) Dark clouds massed on the horizon.

15) There's trouble looming on the horizon.

16) The island was just a dot on the horizon.

17) I could see a ship on the horizon.

18) The ship was a mere speck on the horizon.

19) I descry a sail on the horizon.

20) A few scattered lights shone on the horizon.

21) On the horizon,the sea melted into sky.

22) Storm clouds are forming on the horizon.

23) He descried an island far away on the horizon.

24) There's trouble on the horizon.

25) Smoke appeared on the horizon.

26) Ugly clouds gathered on the horizon.

27) We could see a row of camels silhouetted on the horizon.

28) His eye lit upon a small boat on the horizon.

29) On the horizon, she saw a flash of silver-the sea!

30) A cloud of dust on the horizon announced the arrival of the cavalry.