No, for the LS this is the classic symptom of real overheating due to leaks in the degas tank. That lets air in, and the air pockets cause the heads to go over-temperature. The gauge on the dash normally displays water temperature. When one of the heads overheats, the computer orders the gauge to go to the maximum temperature reading.
The degas tank (and other plastic cooling system parts) only seem to last six to seven years. The cracks that form are too small to easily see, and often don’t leak enough coolant to notice.