Extreme Cold Warning: Essential Insights for Arborists to Prepare

Understanding the Impact of Extreme Cold Warnings

On February 21, 2026, an Extreme Cold Warning was issued by the National Weather Service (NWS) in San Francisco, advising residents to prepare for severe weather conditions. This warning, active from 8:40 AM PST until 9:00 AM PST, emphasized the potential dangers of icy temperatures, which pose risks not just to individuals but also to the environmental health of urban and rural spaces alike. As arborists, we must pay close attention to how such severe weather can affect our trees, both large and small.

Why Weather Alerts Matter to Arborists

When cold temperatures drop suddenly, they can lead to frost damage in trees, particularly for those that are not acclimatized to such low temperatures. During extreme cold spells, trees can suffer from freeze damage, leading to permanent cellular damage that may not be evident until the growing season. Reports in New York City during past extreme cold events highlighted the mortality of numerous urban trees as they struggled to survive harsh conditions.

Impacts on Tree Growth and Health

Extreme cold can inhibit tree growth, as trees enter a state of dormancy to protect themselves. This process can be particularly challenging when prolonged freezing temperatures come after earlier warm spells, influencing flower and leaf production. As the cold wave from January-February 2026 impacted vast regions of North America, including the Midwest to the South, it serves as a stark reminder of the potential for similar weather systems to disrupt local ecosystems.

What Arborists Can Do to Prepare

As professionals who care for tree health and urban forestry, it's essential to develop preparation strategies ahead of predicted cold snaps. Some actionable insights include:

• Inspect Trees: Before cold weather sets in, check for signs of stress or disease that could be exacerbated by extreme temperatures.
• Apply Mulch: Using mulch around tree bases can help insulate roots and preserve moisture.
• Evaluate Location: Consider the placement of saplings or vulnerable trees; those situated in exposed areas are more susceptible to cold injuries.

Lessons from Historical Context

Reflections on the January-February 2026 cold wave, which saw temperatures plunge to unprecedented lows across many states, show us the urgent need for resilience plans within the urban forestry community. Communities in cities like New York have activated cold weather strategies to protect vulnerable trees and the residents who care for them, learning from past weather warnings that often precede significant tree loss.

A Call to Action for Arborists

As a community of caretakers of nature, it’s vital we remain vigilant and proactive as weather patterns shift. Share your knowledge and strategies with your peers, and contribute to discussions on how to better manage our urban forests in the face of extreme weather. To stay informed about local weather conditions and alerts, utilize resources from local government and the NWS to ensure the health of both trees and communities.