It's April 12, and I'm in zone 7A. 64 degrees at 11am with a high of 78, tonight's low is 46. We often have a late frost in early-to-mid May.

Do you think it's too late to sow annual rye grass for a lawn cover?

I have almost an acre of bare ground with a patch of weeds right now, it has a slight slope and is in full sun:

My goal is to prevent erosion, and then sow my permanent cool season grass in September.

If it comes up then I know it will die away by August, which should be perfect. My permanent seed is a blend that includes perenniel ryegrass, so if the annual ryegrass comes back at all then my theory is that it would at least blend in.

This is what I'm looking at:

https://www.amazon.com/gp/product/B0B2M9BB5K/

Thoughts?