An exceptional positive lightning outbreak over Portugal on 4/5 November 2025

Abstract Positive cloud‐to‐ground (CG) lightning is normally a fraction of CG activity but is associated with higher peak currents and disproportionate infrastructure impacts. On 4–5 November 2025, a strong cool‐season frontal system produced widespread lightning over mainland Portugal. Quality‐controlled IPMA data show CG activity concentrated overnight on 4 November, peaking near 0500 utc on 5 November. Of 6128 CG strokes, 1817 were positive, yielding an elevated +CG fraction of 29.7%. Concurrent MTG‐LI observations detected 39 972 total lightning flashes, outlining SW–NE‐oriented frontal rainbands. This demonstrates how integrating satellite total‐lightning data with polarity‐resolved ground networks enhances situational awareness of +CG risk in strongly forced cool‐season convection.