I'd do it now. Many poppies like an early spring start.

If you sow the seeds now, you'd better cover them. Or the wind, water and birds will take care of them....

I've had good luck sprinkling them on the last snow of winter. They do better on deep loose soil. You can also wintersow them in peat pots and plant out while they are quite small.

I wouldn't cover them. They are so small the birds will miss them, but the leaves, mulch, or dirt will smother them if you do cover them.

Sow them now and anytime up to February. Poppyseed needs a cold period to break germination. I've sowed them on top of snow as birdgardener has done and it works great.

Don't cover them. They as so small they fall into the soil by themselves. Covering them will impede germination.
Loretta5

I agree with Loretta and Birdgardener: sow on top of a late snowfall.

I sowed my Flanders poppies directly on one of the last snowfalls last year (February?) and they came up beautifully. I had read this tip here on gardenweb and it totally paid off. Give it a try!

Thanks for this wonderful tip. The poppy seeds I sprinkled on a late snow are popping out everywhere. My WS ones are still a little sluggish.