Greece: Adverse weather forecast across much of the country through at least Jan. 30

Event

The Hellenic National Meteorological Service has issued an extraordinary weather deterioration bulletin warning that weather conditions are expected to deteriorate across much of the country from Jan. 28-30. The adverse weather forecast includes heavy rainfall and thunderstorms in southern and central Greece, heavy snowfall over areas of high elevation, and strong winds.

Rainfall and sporadic thunderstorms are forecast in the eastern and western Sterea, eastern and western Peloponnese, and Thessaly regions, as well as Evia, Crete, the Sporades, Ionian, Cyclades, Dodecanese, and eastern Aegean islands from Jan. 29. Snowfall is expected from late. Jan. 28 in mountainous and semi-mountainous areas of western Macedonia and Epirus, extending to central Macedonia, Thessaly, eastern and western Sterea, Evia, and the central and eastern Peloponnese regions from Jan. 29. Strong northerly winds are forecast in the Ionian Islands Jan. 29 and in eastern regions Jan. 29-30, with 75-88 kph (47-54 mph) winds expected in the southern Aegean.

As of Jan. 28, authorities have issued orange-level snowfall warnings (the second-highest level on a three-tier scale) for Epirus and Central and Western Macedonia. Authorities will likely issue new alerts or update/rescind existing advisories as weather conditions change over the coming days.

Hazardous Conditions
The adverse weather could see rounds of heavy rainfall, snowfall, strong winds, and isolated thunderstorm activity across Greece in the coming days. 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 heavy rainfall has saturated the soil. Power outages could occur throughout the affected area.

Precipitation could fall as snow in the higher elevations over the coming days. Wind gusts could cause blowing and drifting snow; decreased visibility is likely in mountainous areas. There is the possibility of avalanches in mountainous areas where the snowpack has become unstable due to heavy snowfall.

Transport
Floodwaters and related debris may render some bridges, rail networks, or roadways impassable, impacting overland travel in and around the affected area. Flooding in urban areas could also result in significant traffic congestion. Heavy snow will likely make driving hazardous in some areas; authorities could implement temporary road closures or detours in such locations. Mountain passes and tunnels could be closed as a precautionary measure during periods of intense snowfall.

The disruptive weather will possibly cause some delays and cancellations at regional airports. Authorities may temporarily suspend port operations if strong winds trigger hazardous sea conditions, impacting freight and passenger maritime traffic. Flooding or snow could block regional rail lines; freight and passenger train delays and cancellations are possible in areas that see heavy rainfall and potential track blockages.

Disruptions triggered by inclement weather and resultant hazards, such as flooding or avalanches, could persist well after conditions have improved - it could take days before any floodwaters recede and/or officials clear debris. If there is severe damage to infrastructure, repair or reconstruction efforts may result in residual disruptions.

Advice

Monitor local media for weather-related updates and advisories. Confirm all transport reservations. Stay away from elevated streams, creeks, and other watercourses that are prone to flash flooding. Do not attempt to navigate flooded roadways. Exercise caution in elevated terrain due to the threat of landslides. Charge battery-powered devices in the case of prolonged electricity outages.