Originally Posted by CommuteCommando

Actually what is happening is the barometric pressure was rising. If you look at the elevation track it looks like an angled saw blade. The low point is right after he turns onto Lincoln from Jefferson. If you look to the north of that you will see a creek/drainage channel that confirms that the terrain is sloping down in that direction. The difference between there and the opposite corner, Polk and Adams, appears to be about 15-20 ft. If you look at the graph of speed against elevation, the general shape of the elevation profile is confirmed.