Short answer: Lightning risk is not only a safety issue. For commercial property, lightning and surge can affect power, telecom, controls, elevators, access systems, fire alarms, security, rooftop equipment, and tenant operations.
The underwriting file should show which building systems are surge-sensitive and what the downtime consequence would be.
What Official Sources Support
NOAA NSSL explains that cloud-to-ground lightning flashes involve electric current and that positive cloud-to-ground flashes can have sustained current. NSSL also notes that lightning is one of the hazards associated with thunderstorms. NWS lightning safety resources recognize buildings as places of safety for people, but that does not mean building systems face no risk.
The property question is system consequence.
Where Lightning Can Show Up In A Building File
| Exposure | Evidence question |
|---|---|
| Electrical service | Are surge events or outages logged? |
| Fire alarm and life safety | Have panels, sensors, or controls had storm-related failures? |
| Access control | Can tenants enter and secure the building after a surge? |
| Telecom | Are network closets protected and documented? |
| Rooftop equipment | Are controls, inverters, antennas, and conduits exposed? |
| Elevators | Have controls or service been affected by storms? |
| Tenant equipment | Which tenants depend on sensitive electronics? |
The file should identify both landlord systems and tenant-owned dependencies.
Climate And El Nino Context
NOAA CPC and WMO support 2026 El Nino preparedness, but a seasonal outlook does not predict a lightning strike at one building. The practical use is to include thunderstorm-related system risk in the broader weather-readiness file.
If a property already has outage logs, control-board failures, repeated alarm issues, or rooftop electrical exposure, the seasonal review should include those items.
Evidence To Collect
A useful lightning and surge file includes:
- Electrical and telecom room locations.
- Service and outage logs.
- Fire alarm and access-control incident records.
- Elevator controller service history.
- Rooftop equipment and antenna inventory.
- Solar PV and inverter locations, if applicable.
- Tenant critical-equipment register.
- Vendor response contacts.
- Insurance deductible and claim documentation requirements.
The file should not claim protection unless qualified documentation supports it.
Cost Pathways
Costs can include electrical diagnostics, control-board replacement, elevator service, telecom downtime, alarm resets, access-control failures, tenant equipment issues, security overtime, temporary workarounds, claim documentation, and business interruption analysis.
The repair invoice may be smaller than the tenant downtime if communications or access are disrupted.
Stakeholder Translation
Owners and managers use the file to identify system dependencies and vendor response needs.
Insurers and MGAs use it to evaluate equipment exposure and claims context.
Brokers and claims teams use it to organize event timing and affected systems.
Lenders and private credit teams use it to test tenant continuity and reserve adequacy.
Asset managers use it to rank properties where system outages can create income disruption.
The Bottom Line
Lightning and surge risk belongs in physical underwriting because commercial buildings depend on sensitive systems. The best file connects severe weather, power, telecom, controls, tenants, records, and response capacity.
Read next: data rooms and telecom closets, backup power and generators, and tenant critical equipment registers.
Sources and Scope
Source lanes include NOAA NSSL Lightning FAQ, NOAA NSSL Lightning Detection, NWS Lightning Safety, NOAA NSSL Thunderstorm FAQ, NOAA CPC ENSO Diagnostic Discussion, and WMO El Nino/La Nina Update May 2026. This article is not electrical engineering, code, safety, legal, insurance, claim, credit, or investment advice.