See also: Dealing with Breathing Problems written for patients. The term hyperventilation describes excessive ventilation of the lungs, beyond what is required to achieve normal arterial blood gases.
A light frost occurs when the temperature drops to below 32 degrees Fahrenheit, and refers to the conditions that allow a layer of ice crystals to form when water vapor condenses and freezes without first becoming dew. Harvest basil and other tender herbs before a light frost (when the temperature drops to 32 degrees Fahrenheit). 2  Even if they survive the frost, they don't do well in cold temperatures. 3  The same is true for most annuals.
Credit: Andrew Holt Photographer's Choice Getty Images. Besides an air temperature of at least 32 degrees F, frost needs humid air to form. Frost forms on objects when water vapor in the air condenses close to or on the ground. Farmers have developed ways of predicting and preventing the formation of frost on crops. They take into account different aspects of weather such as humidity, wind, clouds and the dew point to determine if there will be a frost.