Perennial or annual ryegrass can be overseeded now but it will take longer for the seed to germinate and the grass to get established in the colder temps. Be patient and keep the seeds moist to be sure that they do not dry out. Extensive watering won’t be required thru the day like in October, but water 2-3 times per day to keep the seeds moist. A light topping of composting or manure material may help insulate the grass as it gets established. If temps dip for any prolonged frost periods, then the grass will struggle. Cooler temps forecast for this weekend may make it a bit more challenging as well. Daytime temps in the 70’s will help.