Will Water Freeze at 27 Degrees? The Simple Answer

No, water will not freeze at 27 degrees Fahrenheit. Pure water freezes at 32 °F at standard atmospheric pressure, so 27 °F is five degrees above that threshold. At 27 °F, water remains liquid — it is simply cold water, not ice.

Why 27 °F Is Not the Freezing Point

The freezing point of pure water is a fixed physical property. On the Fahrenheit scale, the freezing point of water was historically defined as 32 °F Wikipedia — Fahrenheit. That value was set based on the temperature at which pure water turns to ice at sea level under normal atmospheric pressure. At 27 °F, the water is below the freezing point of 32 °F, but it has not reached the temperature required for ice to form. You could leave a glass of water outside on a 27 °F day, and it would stay liquid — though it would be very cold.

One quick example: if you have a thermometer reading 27 °F outdoors, that is about -2.8 °C. Water freezes at 0 °C, so the water is still about 2.8 °C above freezing. It would need to drop another five degrees Fahrenheit to reach 32 °F and begin freezing.

What Would It Take for Water to Freeze at 27 °F?

For water to freeze at 27 °F, something would need to lower its freezing point. That happens when impurities are dissolved in the water. Salt is the most common example. When you add table salt to water, the freezing point drops below 32 °F. A typical saltwater solution used for making ice cream might freeze around 27 °F or lower, depending on the salt concentration. Road crews use this same principle: spreading salt on icy roads melts existing ice because the salt lowers the freezing point of the water, preventing it from refreezing until temperatures drop further.

But for pure water with no dissolved substances, the freezing point remains at 32 °F regardless of how cold the air around it gets. So if someone says “water freezes at 27 degrees,” they are likely talking about saltwater or another solution, not pure water.

Key Takeaways

• Pure water freezes at 32 °F at standard atmospheric pressure, not at 27 °F.
• At 27 °F, water is still above its freezing point and remains liquid.
• The Fahrenheit scale sets the freezing point of water at 32 °F based on historical definitions National Institute of Standards and Technology.
• If you see a thermometer reading 27 °F, expect cold liquid water — not ice — unless other factors like salt or pressure are involved.