The National Weather Service (NWS) uses a standardized system of watches, warnings, and advisories to communicate weather hazards to the public. Among these is the Freeze Watch, which serves as one of the first indicators that widespread freezing temperatures may soon impact a region. Understanding the specific meaning and timing of a Freeze Watch is necessary for proactively protecting sensitive items before the cold air arrives.
Defining the Freeze Watch
A Freeze Watch is an alert issued when conditions are favorable for significant, widespread freezing temperatures to occur. The NWS generally issues a Freeze Watch when air temperatures are expected to drop to 32°F (0°C) or lower. This temperature threshold is significant because it marks the point where water freezes, posing a threat to vegetation and exposed plumbing.
The alert is typically issued 24 to 36 hours in advance of the anticipated cold event. This forecast window allows homeowners and especially agricultural producers sufficient time to enact protective measures. Freeze Watches are most frequently issued during the spring and fall, coinciding with the “growing season” when sensitive plants are most vulnerable to damage from the first or last widespread freeze. This alert is specifically focused on air temperature and does not factor in wind chill, which is addressed by other cold weather alerts.
Differentiating Cold Weather Alerts
A Freeze Warning is the more severe alert, issued when temperatures of 32°F or lower are highly likely to occur for a significant duration. This warning indicates that the freezing event is either occurring or will begin within the next 12 to 24 hours, demanding immediate action to protect assets. Temperatures dropping to 28°F or below for an extended time can cause widespread destruction to almost all types of exposed crops and plants.
The third related alert is the Frost Advisory. A Frost Advisory is issued when minimum temperatures are forecast to be between 33°F and 36°F, and conditions are favorable for frost development. Frost, a thin layer of ice crystals, mainly threatens sensitive vegetation but typically does not cause widespread damage to plumbing or infrastructure. The distinction is in the severity and certainty: a Watch means conditions are possible, an Advisory means a minor hazard is expected, and a Warning means a substantial hazard is imminent.
Essential Preparation Steps
When a Freeze Watch is issued, the extended lead time should be used to enact protective measures for four primary areas: pipes, plants, pets, and people. For exposed outdoor plumbing, water must be prevented from freezing and expanding, which can cause pipes to burst. This involves draining outdoor irrigation systems and hoses, insulating exposed pipes with foam covers, and possibly allowing indoor faucets to slowly drip to maintain water movement.
Protecting Plants and Pets
Sensitive vegetation, especially potted plants and garden vegetables, needs protection from the impending cold. Bringing container plants indoors is the most effective solution. Outdoor plants can be covered with burlap, blankets, or commercial frost cloths before sunset to trap ground heat. Pet owners must ensure that all outdoor animals have warm, dry shelter and access to unfrozen water.
Personal Safety
The public must also take steps to ensure personal safety and the safety of vulnerable community members. Wearing multiple layers of clothing helps retain body heat more effectively than a single heavy garment. It is beneficial to check on elderly neighbors or those with chronic illnesses who may have difficulty securing adequate heating or enacting their own cold-weather preparations.