21.   Cotton fabrics are usually cooler than synthetics because they allow more air to circulate between the fibers.

22.   Cut-up Christmas tree boughs allow air to circulate but moderate the speed of change in soil temperature by keeping the ground in shadow.

23.   Drier air will circulate into the lower Ohio and middle Mississippi Valleys under a mixture of sun and clouds.

24.   During the spring and summer months, homeowners keep their windows open to allow fresh air to circulate through the house.

25.   East of the Appalachians, some sunshine will develop during the day as drier air circulates into the region.

26.   Drier and cooler air will circulate into the Southeast behind a stalled front in the Gulf states.

27.   Drier and slightly cooler air will circulate from the Great Lakes into New England on Thursday as a cold front pushes off the northeast coast.

28.   Drilling the holes allows air to circulate in the cavity, and might clear up the glass, but it is possible that there will be no clearing.

29.   Dull, damp and chilly weather will be the rule over the lower Lakes as cold, moist air circulates around the large area of low pressure.

30.   Farther south, clouds will recede from the Middle Atlantic states as drier air circulates in from the north.