When someone has a blood clot and feel the warmth in the leg, what's exactly happening then?is the blood stuck in 1 spot creating the hot sensation?

Blood clot: A blood clot in the leg usually occurs in a large vein. The clot is irritating to the vein and causes inflammation and swelling and pain. The warmth is from the inflammatory process spreading through the vein.

Clot stuck ?: When a section of a vein stops flowing and clots inflammation develops, like inflamed tonsils in tonsillitis or a sore joint in gout or a sore belly in diverticulitis. The inflammation causes redness, warmth, tenderness and local swelling. With time the inflammation subsides and all those things go away.