Can I apply a pre emergent herbicide now?
You can, but personally, I would wait a bit longer. Crabgrass and other spring germinating weed seeds start to think about germinating when the air and soil temperatures reach 50-55 degrees consistently. According to my soil thermometer, the soil is at 41 degrees. So you have time. And if you’re using pre emergent herbicides that last 45-90 days, I’d wait a bit just so they’ll last longer into the season before I’ll need to re-apply.