The hot water bottle idea is a good one at that age all they need is a place to get warm if they get chilled. I have a broody with three week old chicks in the barn now. Most of the day they are just running around, not huddling under mom. If you have a couple of gallon jugs around you can use a couple of them for the thermal mass. to keep an area warm. If the area they are in is cool maybe make a small tent over them to hold the heat.
The wind really picked up here in SE Pa. in the last half hour.
The wind really picked up here in SE Pa. in the last half hour.