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The study aims to assess the applicability of the current Meso-NH electrical scheme (CELLS) in the investigation of forest fire ignition. Therefore, the challenge is to diagnose cloud-to-ground (CG) lightning at 1 km spatial resolution and, subsequently, preferred regions where Forest Fire Events (FFE) could be naturally ignited. The afternoon of 17th June 2017 has been considered for the study, since the dry thunderstorm environment configured a perfect scenario for natural ignition and evolution of some fires. The Pedrógão Grande wildfire ignited in this period and was the deadliest single fire event in the Portuguese history, with at least 60 people killed. The available observational data are used to validate the numerical results and to provide a brief characterization of the meteorological environment when jointly analysed with the simulation. In addition, cloud microphysics and cloud electrical structure are explored from the model results. The spatial distribution of the simulated CG lightning showed a good agreement with the lightning strokes obtained from the national lightning detection network. Overall, this paper introduces a possible application of the Meso-NH electrical scheme, namely the study of forest fire ignition by lightning strokes. • Cloud-resolving simulation with an explicit electrical scheme • Simulation of the atmospheric environment during "Pedrógão Grande" wildfire • Simulated CG lightning shows a good agreement with observations. • Examination of the likelihood of lightning strokes to explain wildfire ignition • Applicability of an electrical scheme in the investigation of forest fire ignition [ABSTRACT FROM AUTHOR]

The evolution of the meteorological situation during the beginning and the development of the terrible fire of Pedrogão Grande, Portugal, on June 17, 2017, was studied based on numeric simulations with the Meso-NH atmospheric model at 1x1 km horizontal resolution. In the version used, the Meso-NH includes the cloud electrification and lightning scheme (CELLS), a completely explicit 3-D electrical scheme, which allow the simulation of lightning flashes.The simulations indicates the occurrence of a significant number of cloud-to-ground discharges namely on grid points where precipitation do not reach the surface, originating the occurrence of dry thunderstorms and creating favourable conditions to forest fires ignitions. However, according to the model, these discharges did not occur at the time and at the ignition point of the fire. These results are in agreement with data obtained by the system of detection of electric discharges installed and operated by the Portuguese Institute for Sea and Atmosphere (IPMA).The simulations well document the meteorological evolution that favour the rapid development of the fire including the occurrence of a strong downburst. [ABSTRACT FROM AUTHOR]