26 Portuguese municipalities hit top fire risk on Sunday, with the heat alerts already lifted
We counted IPMA's rural fire risk index municipality by municipality for the next three days. Twelve are at the maximum level today, 21 tomorrow and 26 on Sunday — after the heat warnings expire.
Fourteen districts woke up on Friday under a yellow hot-weather warning, and that warning runs out at 6pm on Saturday. That is the part everyone will report. The less comfortable part is what happens next: the heat leaves the warning bulletins while the fire risk is still climbing.
We pulled IPMA’s rural fire risk index — the one civil protection uses to decide where to position crews — and counted all 278 mainland municipalities, one by one, for today, Saturday and Sunday. Twelve sit at the maximum level today. Tomorrow it is 21. On Sunday, 26.
The tier just below tells the same story in bigger numbers. Today 55 municipalities are at very high risk; by Sunday that is 96. Put together, that is 122 municipalities on Sunday — close to half the mainland — in the top two bands of the scale, while the thermometer is on the way down.
Where the maximum sits today
Today’s twelve are almost all in the northern and central interior. Six are in the Guarda district — Almeida, Celorico da Beira, Figueira de Castelo Rodrigo, Guarda, Pinhel and Sabugal. Four are in Bragança: Freixo de Espada à Cinta, Miranda do Douro, Mogadouro and Vimioso. Penamacor, in Castelo Branco, and Pampilhosa da Serra, in Coimbra, complete the list.
By Sunday the map has moved. The worst of it slides south into Portalegre and Santarém, two districts with no municipality at the top level today and five and eight respectively by the weekend’s end. Which is the difference between reading today’s map and planning your weekend around it.
Why risk rises as temperature falls
The index does not measure temperature. It measures the state of the fuel — how much moisture is left in the scrub after days of roasting — and folds in wind and relative humidity. A week of highs above 40C leaves vegetation drying out for days after the thermometer drops, and the thunderstorms forecast for the weekend bring the worst possible pairing: lightning and gusts, with very little rain behind them.
That is roughly how three northern fires burned 5,200 hectares in August in a stretch when the heat warnings had already been withdrawn.
Practically, for as long as the weekend lasts: no burning off, no fireworks, no farm machinery working scrub in the middle of the day. IPMA updates its official municipality-by-municipality risk map every day, and it is a better guide to what you can safely do on Saturday morning than any temperature forecast.
Chart: Tugadaily, with IPMA data