21.   Mature oysters produce clouds of microscopic larvae that drift on the tide until they find a hard surface.

22.   North of the front, winds ascending the sloping terrain will produce clouds, while patchy snow develops in the northern Rockies.

23.   One of his most vivid memories is of the bug truck that rumbled through the neighborhood producing clouds of insecticide.

24.   Onshore breezes will produce clouds and widely separated showers near the western Gulf of Mexico Coast.

25.   The combination will produce widespread clouds along with patches of showers and thunderstorms.

26.   The concrete fragmented into six or seven pieces and produced a cloud of gray powder.

27.   The routine progression of marine air from the Baltic Sea usually produces enough clouds to temper the summer warmth in Moscow.

28.   The return flow of humid air into the upper Mississippi Valley will produce some clouds and scattered thundershowers.

29.   The tail of the front should produce some clouds in southern Texas.

30.   Thunderstorms usually occur when warm, moist air at the ground rises to produce tall clouds.