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.
Canadian Frost Dates. Dates below reflects normal averages for a light freeze (29Â° to 32Â°F, or -2Â° to 0Â°C); local weather and topography may cause considerable variations. The possibility of frost occurring after the spring dates and before the fall dates is 50 percent.