The WMO warned that extreme heat, exceptionally low soil moisture and drought are having a devastating impact on ecosystems, agriculture, river levels, transport and energy, while increasing the risk of fires.

ROME, Aug. 11 (Xinhua) -- A persistent heatwave is tightening its grip on large parts of Europe in August, compounding drought conditions and disrupting river transport, power generation and agriculture in parts of the continent.

Western Europe recorded its hottest June-July period on record, and the trend has continued into August, with some countries experiencing their fourth heatwave since May, the World Meteorological Organization (WMO) said Tuesday, citing figures from the Copernicus Climate Change Service.

In Italy, temperatures are expected to exceed 37 degrees Celsius across much of the country this week and reach 39 to 40 degrees in some inland areas, around 7 degrees above the mid-August average, Italian news agency ANSA reported Tuesday, citing meteorologists.

Belgium's Royal Meteorological Institute has also issued a yellow heat warning, with temperatures forecast to rise sharply from Wednesday and reach around 35 degrees Celsius inland by Friday.

In Central Europe and the Balkans, numerous station and all-time temperature records were broken in countries including Austria, Hungary and Slovakia during the first week of August, according to the WMO.

The WMO warned that extreme heat, exceptionally low soil moisture and drought are having a devastating impact on ecosystems, agriculture, river levels, transport and energy, while increasing the risk of fires.

In Bosnia and Herzegovina, water levels in several rivers have fallen significantly. The Sava River basin authority warned that without substantial rainfall in the next 10 to 15 days, water levels could approach record lows.

Germany's Rhine, one of Europe's most important industrial waterways, has also fallen to historically low levels. At Kaub, a key gauge for inland shipping, the water level has dropped below the previous record low set in 2018. The shallow water is forcing cargo vessels to reduce their loads, requiring more ships to carry the same volume of goods and driving up freight costs.

High temperatures have further strained power systems, as low water levels affect the cooling of power-generating facilities while demand for air conditioning and refrigeration rises.

In Poland, grid operator Polskie Sieci Elektroenergetyczne invoked emergency measures on Thursday to ensure electricity supplies amid the heatwave, the English-language news outlet Notes from Poland reported.

It was the second activation in three days and the third this summer, the outlet said. Low water levels in the Vistula River, Poland's longest river, also forced state-controlled energy company Enea to reduce operations at two coal-fired plants, taking around 1.1 GW of generation capacity offline.

Agriculture is facing mounting pressure as well.

In Belgium, public broadcaster VRT NWS reported that heat stress was reducing yields and producing smaller open-field vegetables, including broccoli, cauliflower and leeks. Greenhouse tomatoes were ripening faster, while strawberries were also becoming smaller.

Persistent drought has forced some Belgian growers to irrigate their crops daily, compared with once or twice a week under normal conditions, according to VRT NWS.

Italy's wine industry is facing similar pressures. Hot and dry weather has brought forward grape harvesting in several regions, with picking already underway unusually early in parts of the country.

Marco Caprai, a wine producer in Italy's central Umbria region, told ANSA that prolonged drought and high temperatures could leave regional grape output 5 to 10 percent below average this year.