we have hundreds of coriander seedlings that came in the home made compost and they didn't die in the intense cold, either ;D
Yeah, quite recently I read you could grow coriander over winter and it's true - a bit of protection and it's fine - the stuff on my warm SE facing front wall does even better in a normal winter - probably because of the air movement - not so good this year.
As to actual weed seedlings - if you have time (a big if) prepare the ground including the drills, then let the weeds grow an inch high before covering them with black plastic or cardboard etc. until they die (lifting the mulch to look actually helps - it triggers more germination without giving the weeds enough light to survive).
When you remove it you can sow into undisturbed drills - cover the seeds with used growbag compost to avoid exposing more weed seeds to the light.
You will never get them all but it makes seedy soil behave more like normal well-managed soil.
Cheers.