I suppose it depends on how warm your soil temperature is. I think they will germinate at soil temperatures as low as the lower 40s. However, a worst possible case scenario also could occur as they could sprout and then get hit hard and frozen by a sudden change in the weather before they've been growing long enough to do much or to develop any tolerance of the cold. The reason we usually plant them in autumn is to give them a chance to get well-established before the cold arrives. Planting them this late means they won't have had time to harden off to the cold weather that seems inevitable to arrive again in January. It's kind of risky to plant them so late, but it also is one of those things that might work out if the weather is on your side, and if the soil is warm enough.