Adjective
subfreezing (not comparable)
Colder than the freezing point of water; below 0 degrees C or 32 degrees F.
The arctic cold front brought subfreezing temperatures, snow, freezing rain and treacherous driving conditions.
Averages in July of a high of convert and a low of convert in Artigas confirm the milder winters in northwestern Uruguay, but even here temperatures have dropped to a subfreezing convert. Source: Internet
San Antonio receives about a dozen subfreezing nights each year, typically seeing some sort of wintry precipitation about once every 2-3 winters (i.e. sleet/freezing rain), but accumulation and snow itself are very rare. Source: Internet