Frost hit Iowa Monday night, though only over the northern part of the state. Brad Small, a forecaster at the National Weather Service in Des Moines, says temps dropped in the northern half of Iowa into the low thirties, and came within a few degrees of breaking records in some spots. He says it was mainly north of Highway 30, and down into the Nishnabotna Valley and into Atlantic and Audubon. Meteorologist Small explains Monday’s gusty winds died down and that helped allow the frost to form. Frost is more apt to form when winds are light, so when it got clear and calm after sunset, it let temps cool down to freezing. But Small says there’s not much chance it’ll be that nippy again tonight. He sees a warming pattern for a day or two, though there’s another chance for frost near the end of the week. Though it’s earlier than Iowa’s average date of “first frost,” Small says this spell of cool weather is nothing radically out-of-the-ordinary.