November is a strange month for Dallas. It could be 80 F or it could be 50 F. I would reccomend pants and T Shirt/Polo/Long Sleve button down with a medium jacket/coat in case its on the cooler side. That should cover you for most early November weather.
Early November is usually pretty mild but you can't count on it. That's about the time I put my shorts away for the year and start wearing long pants and jeans.
Basically, we have two seasons in Dallas: "Hot" and "Damn Hot" - for a displaced northern boy, I have yet to see anything that I could really consider winter. Yeah, maybe a day of snow here and there, but it never sticks. For a northerners perspective, November in Dallas is a lot like September up north. Generally not too bad, and we are still cutting grass with a vengeance . . . . cool nights, but it can still be high 70's to 80's in the daytime. Hence, November, at least to me is in the "Hot" season. 110 and blinding sun in August - that's "Damn Hot"!!!
Lord knows how I'd like to live back up north again . . . .