What does it mean when a stock's volatility keeps increasing?

Filter Lab calls this warming. A warming stock is one whose range of movement is still getting wider rather than already wide. It is the trend in the range, read over a rolling 90-day window, not the level of the range at a single moment.

What is a warming stock?

A stock whose measured turbulence is still rising. It may already sit in a high turbulence band or a lower one; what makes it warming is that its range is continuing to expand rather than settle.

Is warming the same as high volatility?

No. High volatility describes how wide a stock's range is now. Warming describes whether that range is still widening. A stock can be highly volatile but steady (wide, not warming), or only moderately volatile and warming (its range still building).

Warming: when a stock's turbulence is still rising

Warming is Filter Lab's term for a company whose measured turbulence is still increasing. In traditional terms it is closest to expanding realized volatility, but it describes the trend in a stock's range rather than its level.

In traditional finance this is closest to increasing (expanding) realized volatility. Filter Lab measures it more precisely; the difference is below.

In everyday market language, the nearest idea is a stock whose realized volatility is still increasing. Filter Lab calls that warming, and the word carries a distinction the common phrase leaves fuzzy.

Warming is not a level. It is a direction. A stock’s turbulence band tells you how wide its recent range of movement has been. Warming tells you something separate: whether that width is still growing. A name can sit in a high band and be steady, its range wide but no longer expanding, or sit in the same band and be warming, its 90-day turbulence trend still pointing up. Same location, different direction of travel.

Why the distinction matters

Most volatility language collapses these two things into one number. “This stock is volatile” could mean its range is wide, or that its range is growing, and those imply different things. A wide-but-steady name has already repriced its uncertainty. A warming name has not settled yet. Reading the two together, where a stock sits and whether it is still moving, is more informative than either alone.

How it is measured

Warming is read per company off a rolling 90-day turbulence trend. When that trend is still rising, the name is warming. Filter Lab reports it across the hot cohort, the companies in the top two turbulence bands, as the share that is still warming rather than leveling off. Turbulence itself measures the range of a company’s movement, not its direction, so warming says the range is still widening, not which way the stock will go. The computation is held stable over time so the series stays comparable.

Wide is not the same as widening

This is the misconception to clear. A high turbulence band sizes the door: it says the range of what could happen is large. Warming says the door is still getting wider. Neither points a direction. A warming name is not a falling one; it is one whose behavior has not settled.

Today’s reading, and the record

The share of the hot cohort that is warming is published every session-day in the Daily Breadth dataset, alongside Hot Share and the turbulence bands. The live figure at the top of this page is today’s.

Descriptive, not advice. Warming measures the range of a company’s movement, not its direction. See it at work in the daily Market Analysis.

Warming: when a stock's turbulence is still rising

Why the distinction matters

How it is measured

Wide is not the same as widening

Today’s reading, and the record

Common questions

See these gauges read every week