Health authorities issued a red alert for two-thirds of the country on Wednesday as the prolonged heatwave sweeping Italy pushes temperatures well above average for the end of June.

The cities and provinces of Ancona, Bologna, Bari, Cagliari, Catania, Campobasso, Civitavecchia, Florence, Frosinone, Latina, Messina,, Naples, Venice, Palermo, Perugia, Pescara, Rieti, Reggio Calabria, Rome and Viterbo were warned to expect conditions that could be harmful to health under the highest alert level.

By Thursday, every part of Italy is under either a red or amber heat alert, except for the northern provinces of Turin, Genoa and Bolzano.

Red warnings indicate emergency conditions with possible negative effects on everyone’s health, while amber warns the heat may pose a health risk, particularly to the elderly, children and those with chronic illnesses.

Peaks of 40C were recorded on Tuesday, when 12 areas were already on red alert and many others on a lower-level amber alert due to the intense heat.

Meanwhile, the northern Italian regions of Emilia Romagna, Liguria, Lombardy, Piedmont, Tuscany, Trentino Alto Adige, Val d’Aosta and Veneto are braced for rain and thunderstorms between Tuesday and Wednesday.

The current heatwave, the latest in a series to have already hit Italy this year, has worsened wildfires and drought hitting many parts of the country after months of low rainfall and an unusually dry winter.

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The Po, Italy’s longest river, was up to 80 percent lower than usual on Monday according to Fabrizio Curcio, head of the civil protection department.

The department hasn’t ruled out the necessity of water rationing measures during the day, with restrictions on water use already in place in many towns in drought-hit areas.

Several regions have asked to be granted a ‘state of emergency’ under the government’s much-anticipated decreto siccità (drought bill), which is expected to be announced by the end of this week.

Experts have repeatedly warned that intense droughts and longer, earlier heatwaves are among the consequences of climate change.