ITB is usually more of an overuse issue. In your case, I am inclined to suspect a strain to one of your muscles after jumping that stump.

Muscles react to cold, because one of their main jobs is heating your body by burning glycogen (why we shiver). The lateral quad (Vastus Lateralis) is under the ITB, and would be the first muscle exposed to the air when you get out of your car. It would also act as a shock absorber during jumping and running.

Sitting in a chair, reach over the affected thigh with your fingers, just above the knee (while sitting, just toward the hip) on the lateral part of your quad, and reach under the ITB and quad (by curling your fingertips under it) and pull it upward. See if you find sensitivity under there. Sometimes after trail running, I have to rub that area at stop lights on my way home. That muscle is famous for getting loaded with painful knots that are noticeable during exercise. It's hard to get to most of it because of the hard, flat ITB on top.

The hip stretches are good, although it is hard to stretch them much on a normal person. Check the hip stabilizer muscles in the upper glutes and forward on the hip (TFL) which tension the ITB and sustain a lot of impact when one leg strikes the ground.

http://en.wikipedia.org/wiki/Muscles_of_the_hip

My bout with ITB lasted a couple months. My method of pain control was various forms of magnesium and kinesio tape. Mag is an all-purpose nutrient that relaxes muscles when applied topically or used orally. It is mildly laxative, though. The tape was shaped and secured to lift the kneecap slightly and counteract the pull of gravity on the area. I cut my mileage some but made all my long runs - so far, 4 of marathon distance or longer. Everything seems to be back to normal now, about 3 months out from onset.