Preparing Your Property and Trees for El Niño: A Bay Area Storm Readiness Guide
How proactive tree care can help reduce storm-related tree damage before the weather arrives
As we move toward fall, Bay Area property owners should begin thinking about winter storm preparation. Trees that appear stable during calm weather can be subjected to dramatically different forces during major storms, and existing structural or root defects may become failure points when wind, rain, and saturated soils combine.
NOAA currently forecasts a very strong El Niño for the 2026–27 winter, with more than a 90% chance of a very strong event during the Northern Hemisphere fall and winter. El Niño does not guarantee a particular storm pattern at every location, but stronger events can increase the likelihood of certain weather impacts.
For homeowners, the important question is not simply what the weather may bring. It is whether your trees are prepared to withstand it.
Why Storms Cause Trees to Fail
Storm-related failures often occur when wind, rain, and saturated soils combine with existing defects. Strong winds increase loading on branches, stems, and roots, while rain can add weight to dense canopies. Meanwhile, saturated soils can reduce the friction and resistance that help hold roots in place. Defects such as decay, cavities, weak branch unions, overextended limbs, and compromised root systems can become failure points under these increased loads.
Understanding these conditions is the first step toward preparing your trees for the demands of storm season.
Preparing Your Trees for Storm Season
Don’t wait until severe weather arrives. Proactive tree care provides an opportunity to identify concerns while conditions are safe and make thoughtful decisions about how to manage them.
A comprehensive storm-preparation program may include:
- Tree Risk Assessment
Identify structural, health, and site conditions that may increase risk. - Root Crown Inspection
Look for defects or conditions that may compromiseoverall stability. - Aerial Inspection
Evaluate important canopy defects that cannot be fully assessed from the ground. - Targeted Pruning
Reduce deadwood, excessive end-weight, and specific structural concerns whereappropriate. - Supplemental Support
Consider cabling or other support systems for appropriate structural defects. - Ongoing Monitoring
Establish a plan for trees that require continued observation oradditional investigation.
Prepare Your Property, Not Just Your Trees
Storm preparation should also consider the area surrounding your trees.
Identify important targets such as:
- Homes and other structures
- Driveways and parked vehicles
- Walkways and outdoor gathering areas
- Fences and neighboring properties
- Power lines and other infrastructure
Understanding what could be impacted by a tree or branch failure helps arborists evaluate the risk associated with a particular defect and prioritize recommendations.
A structurally compromised branch over an open portion of the property may represent a very different risk than the same branch over a house, driveway, or frequently occupied area.
Start With a Professional Tree Inspection
The first step in preparing your property should be understanding the condition of the trees already there.
A Tree Risk Assessment performed by a Certified Arborist can identify visible defects and conditions that may increase the likelihood of failure during severe weather.
Ground-level inspections can evaluate the trunk, root crown, major branch attachments, canopy condition, and surrounding site conditions. However, some structural problems cannot be fully evaluated from the ground.
Root Crown Inspections
The roots are the anchor of the tree, providing the stability needed to withstand the forces of wind and weather.
Root crown inspections can identify conditions such as buried root crowns, girdling roots, decay, cavities, fungal activity, or other abnormalities that may affect tree stability.
This is particularly important before a storm season because a tree with a compromised root system may be more vulnerable when saturated soils and high winds occur together.
Where appropriate, additional investigation may be recommended to better understand suspected defects below grade.
Aerial Tree Inspections
Many of the most important defects in a mature tree occur high in the canopy.
An aerial inspection allows a Certified Arborist to get close to major branch unions, cracks, cavities, decay, previous failures, and other structural concerns that may not be visible from the ground.
For large trees with valuable targets below them, an aerial inspection can provide a much more complete understanding of structural condition before storm season. This information can help determine whether pruning, supplemental support, additional investigation, or monitoring may be appropriate.
Proactive Pruning Before the Storm
Storm preparation does not mean removing large portions of a tree’s canopy. Improper pruning can actually undermine a tree’s natural structure and increase the likelihood of failure during a storm.
Rather than making a tree safer, improper pruning can leave remaining branches more exposed to wind loading and increase failure potential. Practices such as lion’s-tailing, which strips interior and lower branches from the canopy, can remove important foliage and alter the way a tree distributes weight and responds to wind.
Proper end-weight reduction pruning takes a more targeted approach by selectively reducing weight toward the ends of limbs. This strategy maintains healthy foliage and the tree’s natural structure, while reducing the forces exerted on branches and mitigating the likelihood of failure.
Depending on the tree and its condition, storm-prep pruning may include:
- Removing dead, broken, or hazardous branches
- Reducing excessive end-weight on long or overextended limbs
- Improving clearance from structures and other targets
- Addressing selected structural defects
The objective is not simply to make the canopy smaller. It is to reduce specific sources of structural stress while preserving as much healthy canopy as possible.
Support Systems for High-Value Trees
Some trees have structural defects that cannot or should not be addressed through pruning alone.
In appropriate situations, support cable systems can provide supplemental support to weak or vulnerable branch unions and stems. Properly designed and installed systems can help manage loads while allowing the tree to retain its natural structure.
Support systems are not appropriate for every tree or defect. Their use should be based on a professional assessment of the tree’s structure, condition, and site.
Prepare Now. Reduce Risk Later.
No pruning program or inspection can guarantee that a tree will withstand every storm. Trees are living structures, and severe weather can produce forces far beyond normal conditions.
However, proactive assessment and thoughtful tree care can identify weaknesses, reduce unnecessary loading, and provide property owners with better information before severe weather arrives.
Storm preparation starts with knowing your trees.
Ned Patchett Tree Care & Consulting helps homeowners, property managers, and developers throughout the Peninsula and greater Bay Area evaluate and manage tree risk through professional Tree Risk Assessments, aerial inspections, structural pruning, support systems, root crown inspections, and consulting services.
If you would like to have your trees evaluated before the upcoming winter storm season, please email ned@nedpatchettconsulting.com or call (650) 728-8308.