white heat

a stage of intense activity, excitement, feeling, etc.: The sales campaign is at white heat.

an intense heat at which a substance glows with white light.

Origin of white heat

First recorded in 1700–10

Yet he could not escape the feeling that even at the white-heat of passion she was enjoying her scene.

Lady Lilith |Stephen McKenna
I am speaking of the third and fourth decades of the century, and political excitement was at white-heat.

Round About the Carpathians |Andrew F. Crosse
The noon meal is rushed through, perhaps when the brain is at white-heat.

How to Get Strong and How to Stay So |William Blaikie
If I read history aright, it is only the white-heat of fanaticism which brands a true word into the tough hide of society.

The Atlantic Monthly, Vol. 12, No. 72, October, 1863 |Various

All creatures, from the tiniest insect upward, were in reality busy under that curtain of white-heat haze.

The Open Air |Richard Jefferies

white heat

intense heat or a very high temperature, characterized by emission of white light

informal a state of intense excitement or activity