Every major Italian city hit the highest heat alert at once, for the first time on record
It's not just the daytime heat. It's that the nights aren't cooling down anymore either.
Italy's Ministry of Health tracks heat danger across 27 cities, and as of this week, 25 of them are on the highest possible warning, bollino rosso, or red alert. The last two, Messina and Reggio Calabria, are expected to join within days. If they do, it'll be the first time in Italy's recorded meteorological history that every city in the network has hit maximum alert simultaneously. Eleven cities were on red alert just a week earlier, on August 1, and the number climbed every single day after that.
Inland temperatures above 40°C get the headlines, but the number the health ministry actually watches more closely is the overnight low, and this year it isn't dropping below 25°C in a lot of these cities. That matters because a body under heat stress needs the night to recover, and if it doesn't get that window, the health risk compounds day over day instead of resetting. That's a large part of why this is being called a historic milestone and not just another hot summer.
The health ministry's daily bulletin is the thing to watch, since it updates in real time as cities move on and off red alert. Greece is dealing with a related wildfire crisis in the same window. It's its own story, but a connected one, since an unusually persistent heat pattern is sitting over Southern Europe right now, not just Italy.