Stove went out..

Do a good cleaning on the stove and pipe
Make sure ash pan is shut tight and door seals

What brand stove do you have?

This has happened before to me just lately,and with this weather,I can understand why. If you've ever played with the draft on your stove when it is trying to light with the electric ignitor,you can see that there is a "sweet spot" where the right conditions are such that the draft and the fire allow the pellets to ignite.Same as if you were trying to start a campfire the hard way with just a spark and blowing on it.If you go away and leave the stove for overnight use and leave the draft open too far,there is a chance that the pellets may not catch.Even compounding the problem more is when you have a weather event with winds.I bet the bet is fine-just that the fire did not catch.

I'm running a Harman P61A in my basement, and have recently been experiencing the same issues with the stove going out at random times. I'll come down and find the burnpot full of fresh, unburned pellets. Sometimes it will relight after I empty the burnpot, and other times (like this morning), it refuses to light after 3 attempts. Stove is only 1 year old, and gave it a thorough cleaning two days ago.

Could it be as simple as adjusting the draft as mentioned above? Is that accomplished by sliding the burnpot cleanout slide open a little bit?

I'm just trying to be helpful and don't know all the ins and out of your stove,but I would say you had a very good opportunity to make some adjustments with the previous failed attempts-as they are happening.If you can see the reddish glow of the ignitor to show that it is in fact working,the only other factor,barring wet pellets,is a draft issue.