Following a mild end to August, temperatures are set to rise significantly across Portugal, with the Portuguese Institute for Sea and Atmosphere (Instituto Português do Mar e da Atmosfera or IPMA) forecasting highs exceeding 35ºC. Some interior regions of the Alentejo may see temperatures reach or surpass 40ºC by mid-week. The warming trend is attributed to the influence of an anticyclonic region near the Bay of Biscay.
Temperatures to climb above 35ºC across Portugal this week
Sunday, 30 August 2026AI summary
Context & Explainers
A red warning is the highest alert level issued by Portugal's weather agency, the Portuguese Institute for the Sea and the Atmosphere (Instituto Português do Mar e da Atmosfera or IPMA), used when conditions pose a very high risk to life and property. Under a red warning authorities may close roads, suspend transport and advise people to avoid coastal and flood‑prone areas, so follow civil protection instructions during the Friday–Saturday storm period.
