GreenlyPortugal: frost dates by city
The average last spring frost and first autumn frost in Portugal, from ten years of weather.
| City | Last spring frost | First autumn frost | Frost-free days |
|---|---|---|---|
| Lisbon | none in ten years | none in ten years | — |
| Porto | 26 January | 19 December | 327 days |
Median of 2016–2025 for the 25 km grid cell of the city: the last day at or below 0 °C in spring and the first in autumn (ERA5 reanalysis via Open-Meteo). In a cold year a frost can come a week or two later — Greenly warns 48 hours ahead.