Yesterday I mentioned the first frost in Colorado. But, why does frost occur at all? It happens when the temperature of the Earth’s surface falls below freezing. The freezing temperature ensures that water condenses on the surface and becomes ice.

There are several degrees of frost:

A light freeze is when temperatures are between 29 and 32 degrees (F). During a light freeze, tender plats may be killed, with little destruction to heartier vegetation.

A moderate freeze is when temps are between 25 and 28 degrees (F). During a moderate freeze, there can be wide destruction on most vegetation with heavy damage to fruit blossoms and semi-hardy plants.

A severe freeze is when the temps are 24 degrees (F) and colder (as was the case in Colorado) yesterday which causes heavy damage to most plants.

The trick to this in the early fall is that the temps, while they may drop, are usually at the low mark for an hour or so. And, the ground and plants can absorb and retain some warmth from the morning sun during the day. Water in pipes freeze when the temp remains at 24 (F) or colder for many hours and/ or days. If you live in New Orleans where the insulation in buildings is relatively nonexistent, folks will leave their taps dripping when they know the temp will drop below 32 degrees.

It may be warm and pleasant today but Fall and Winter temps are coming.

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