27 Sep 2022 | 12:34 PM UTC
Switzerland: Adverse weather forecast across central, northeastern, and western regions through at least Sept. 29
Heavy rainfall forecast across parts of central, northeastern, and western Switzerland through at least Sept. 29. Disruptions possible.
Event
Severe weather is forecast to occur in parts of central, northeastern, and western Switzerland through at least Sept. 29. Persistent rainfall is expected over western Alpine regions through at least noon Sept. 29, with rainfall totals of 5-9 cm (2-3.5 inches) possible and isolated amounts of around 10 cm (4 inches). Further rainfall is expected across the rest of the affected area and snowfall is likely in elevated areas.
As of Sept. 27, MeteoSwiss has issued the following weather warnings across the affected area:
Orange heavy rain warnings (second-highest level on a four-tier scale): Across parts of southwestern and south-central Switzerland.
Yellow heavy rainfall warnings: Across much of the rest of the affected area.
Yellow heavy snowfall warnings: Across some central and northeastern areas.
Officials could update and possibly extend the coverage of weather alerts over the coming day.
Hazardous Conditions
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 or a lack of 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 cannot be discounted in hilly or mountainous areas, especially where the soil has become saturated by heavy rainfall. Disruptions to electricity and telecommunications services are possible where significant winds, flooding, or landslides impact utility networks.
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. Rain-induced landslides cannot be discounted in areas of elevated terrain; there is also the possibility of avalanches in mountainous areas where the snowpack has become unstable due to heavy snowfall
Transport
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. 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.
Severe weather could also trigger flight delays and cancellations at regional airports. Flooding could block regional rail lines; freight and passenger train delays and cancellations are likely in areas that see heavy rainfall and potential track inundation.
Advice
Monitor local media for weather updates and related advisories. Confirm all transport reservations and business appointments before travel. Make allowances for localized travel delays and potential supply chain disruptions where flooding has been forecast. Do not drive on flooded roads. Charge battery-powered devices in the case of prolonged electricity outages.
