My leghorn is one of my best foragers & she goes out in any kind of weather.I'm not sure if this helps or not, but ours are let out of the coop at 6:30am daily to run around their 1600sf pasture. When it's cold, they can go back in the covered run (that has old clear storm windows on it to entirely block the wind). They seem to be outside as much as possible--when it's cold, when it's muddy, and even a bit when it's snowing. My best foragers are these 10 laying girls. The pullets are out too, but not quite as much as the Comets/Leghorns. Whoever said Leghorns aren't cold hardy or good foragers hasn't met these girls!