In this study, previous work on triggered lightning is reviewed and case studies are examined in order to identify common meteorological conditions for helicopter-triggered lightning strikes. Using forecast data from the Met Office Unified Model, an algorithm for triggered lightning risk was produced based on outside air temperature and precipitation rate. Evaluation against past helicopter strike cases has demonstrated that the new algorithm successfully forecasts lightning risk on 80% of occasions when triggered lightning occurred. In addition, the algorithm correctly forecast 8/9 natural lightning strikes which were observed in the operating area during winter 2010–2011. The areas of risk highlighted are usually small, which should allow helicopter operators to plan flights around high risk regions. The information in this study can also be used to inform helicopter operators of the likely conditions in which triggered lightning strikes occur.