First frost predicted tonight

Published 12:00 am Tuesday, November 9, 2004

Be prepared to shiver.

While it’s a week-or-so behind what’s normal for the Roanoke-Chowan area, local residents stand a good chance of seeing the fall’s first frost tonight and early Wednesday morning.

Monday, the National Weather Service office in Wakefield, Va. issued a Special Weather Statement for most all of northeastern North Carolina, excluding the Outer Banks. That statement deals with what may be the first widespread frost of the fall season.

Temperatures began to fall yesterday (Monday) as a strong dome of cold high pressure built in over the local area. Clear skies and light winds will allow for rapid cooling during the overnight hours. There, with the thermometer hovering around the freezing mark, frost is expected to develop over the region.

Local residents are warned to protect any plants or vegetation that are outdoors.

Frost occurs when water vapor freezes on a surface when the temperature reaches 32 degrees or below. It usually occurs on a clear night when heat radiates up from the ground. Tiny ice crystals form when water vapor condenses. Similar to dew, the temperature at ground level is the key. The temperature there is often colder than the air temperature just a few feet higher. Tender plants need to be covered for protection from frost.

Freeze involves a 32-degree surface temperature that lasts for a significant length of time. Frost is not necessarily present. Vegetation damage is usually a result.

A hard freeze is usually defined as 25 degrees or below. The term killing freeze or frost depends upon the hardiness of the plant and the level of exposure.

According to the vegetation experts at Lowes Home Improvement, tender, herbaceous plants are more likely to suffer form frost than hardy, woody plants. When sustained temperatures are at freezing or below, long-term protection is usually not feasible. But in the event of an early fall or late spring cold snap, you can provide temporary protection. Methods of safeguarding plants vary.

Cover plants with specially designed row covers or common household items such as cloth, paper or plastic. In extreme cold, try to prevent the cover (especially plastic) from contacting foliage. The cold can damage the leaves. A simple wooden frame can be draped with the cloth or plastic sheets. The radiated heat will be kept inside.

A layer of mulch will also help retain the heat from the soil to protect from cold.

The extended forecast for the remainder of the workweek calls for mostly sunny skies and warmer temps on Wednesday and Thursday and partly sunny skies on Friday. Highs on those three days will range from the mid 50’s to low 60’s. Overnight lows are expected to be in the mid 30’s to around 40 degrees.