Italy: Heatwave forecast to persist over much of the country through at least July 8 /update 3

Event

Forecast models indicate that the ongoing heatwave will persist across much of Italy through at least July 8. The heatwave is forecast to peak over the coming days, before abating in northern parts of the country July 6-7 and central and southern parts July 7-8. Temperatures of between 32-37 C (84-99 F) are expected across much of the country, with peaks of over 40 C (104 F) in parts of southern Italy. The Italian Meteorological Service has warned that maximum temperatures above 38 C (100 F) are possible in Basilicata, Puglia, Sardinia, and Sicily regions July 1-3. Health authorities have issued their highest red alert levels for 19 out of 27 cities across Italy July 1.

The hot weather is expected to be punctuated by thunderstorms in some northern areas over the coming days. The storms may be intense and accompanied by heavy downpours, strong wind gusts, lightning, and hail storms. Possibly severe thunderstorms are expected July 1 over parts of northern Piedmont and northern Lombardy regions.

The hot weather will likely exacerbate the situation in many northern and central areas that are experiencing severe drought. Several regions have declared regional states of emergency in recent days due to the drought crisis, including Lazio June 20, Emilia-Romagna June 21, and Lombardy June 24. Other regions are expected to take similar measures in the coming days and central government is reported to be preparing national legislation regarding the drought. Some restrictions on water usage are ongoing in affected regions.

As of July 1, authorities have issued the following weather warnings across Italy:

• Red heatwave warnings (the highest level on a three-tier scale): Basilicata and Sicily regions.

• Orange heatwave warnings: Puglia and Sardinia regions.

• Orange thunderstorms warnings: Lombardy and Piedmont regions.

• Yellow heatwave warnings: Calabria, Campania, Marche, and Molise regions.

• Yellow thunderstorm warnings: Friuli Venezia Giulia, Trentino-South Tyrol, and Veneto regions.

Authorities will likely issue new alerts or update/rescind existing advisories as weather conditions change over the coming days.

Hazardous Conditions
The extended period of oppressive heat and dry conditions may produce ideal circumstances for wildfire growth throughout the region. Heatwaves also pose a threat to vulnerable groups - such as the elderly, children, pregnant women, and those with respiratory illnesses - due to the increased possibility of heat stroke or heat exhaustion during prolonged exposure to high temperatures. These health risks could also extend to relatively healthy individuals during significant heatwave events. In addition to significantly impacting athletes and those who work outdoors, high temperatures can cause problems for people using mass transit. The lack of air conditioning and cramped vehicles during rush hour may lead to some passengers being hospitalized for dehydration.

In areas where thunderstorms occur, sustained heavy rainfall could trigger flooding in low-lying communities near rivers, streams, and creeks. Urban flooding is also possible in developed areas with easily overwhelmed stormwater drainage systems. Sites located downstream from large reservoirs or rivers may be subject to flash flooding after relatively short periods of intense rainfall. Landslides are possible in hilly or mountainous areas, especially where the soil has become saturated by heavy rainfall.

Transport and Utilities
Very high temperatures may warp rail tracks and force passenger and freight trains to operate at reduced speeds. Road surface damage is also possible, and overheated vehicles may worsen traffic problems in urban areas where congestion is already a problem. Commercial trucking disruptions might occur, as very high temperatures put more stress on engines, making tire blowouts more common. Major flight disruptions are unlikely at regional airports, but general aviation disruptions are possible, and some airfreight carriers could reduce cargo loads. High temperatures could lead to an increased demand for electricity, which might trigger localized brownouts or blackouts, exacerbating hazardous conditions when air conditioning is no longer possible.

Following thunderstorms floodwaters and debris flows may render some bridges, rail networks, or roadways impassable, impacting overland travel in and around affected areas. Ponding on road surfaces could cause hazardous driving conditions on regional highways. Authorities could temporarily close some low-lying routes that become inundated by floodwaters.

Advice

Monitor local media for weather updates and related advisories. During heatwaves, remain indoors in air conditioning when possible. If outdoor activities are necessary, frequently rest in shaded areas; avoid activity during the hottest times of the day. Stay well-hydrated by drinking plenty of fluids. Avoid alcoholic beverages, which are dehydrating; drink water that is bottled or has been boiled. Wear loose-fitting, light-colored clothing. Cotton fabrics are more cooling than synthetics. Promptly seek medical attention if signs of heat exhaustion or heat stroke develop. Charge battery-powered devices in case prolonged electricity outages occur.

Resources

Italian Meteorological Service