08 Aug 2022 | 08:09 AM UTC
US: Adverse weather forecast across parts of the Upper Midwest and Ohio Valley regions Aug. 8
Severe weather forecast across Upper Midwest and Ohio Valley regions, US, Aug. 8. Possible Flooding and associated disruptions.
Event
Heavy showers and thunderstorms are forecast across parts of the Upper Midwest and Ohio Valley regions Aug. 8. A stalling weather front is expected to bring heavy downpours to parts of the Upper Great Lakes and Upper-to-Mid Mississippi Valley through the morning hours of Aug. 8. Rainfall totals of around 5-10 cm (2-4 inches) are possible during storms. Heavy rainfall could result in floods and flash floods, especially over low-lying areas or areas close to water bodies.
Government Advisories
As of early Aug. 8, the National Weather Service (NWS) has issued flood watches across portions of central and southern Wisconsin, far southeastern Minnesota, northeastern and eastern Iowa, and northern Illinois.
The NWS's Weather Prediction Center (WPC) has warned of a "Moderate Risk" (Level 3 on a four-tier scale) of excessive rainfall across portions of southern Wisconsin, far southeastern Minnesota, eastern and northeastern Iowa, and northern Illinois. There is a "Slight Risk" (Level 2) of excessive rainfall for areas surrounding the Moderate Risk area, including parts of central Wisconsin, southeastern Minnesota, northern, central, and eastern Iowa, northern Illinois, northern Indiana, far northwestern Ohio, and southern Michigan. Officials could update and possibly extend the coverage of weather alerts over the coming days.
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 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.
Authorities could issue mandatory evacuation orders for flood-prone communities over the coming days and tornado warnings advising the public to shelter in place. Disruptions to electricity and telecommunications services are possible where severe weather impacts utility networks.
Transport
The severe weather will likely contribute to transport disruptions throughout the region. Floodwaters and debris flows could 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.
Severe weather will also likely trigger flight delays and cancellations at airports across the affected region. 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.
Localized business disruptions may occur in flood- or tornado-hit areas; some businesses might not operate at full capacity because of damage to facilities, possible evacuations, and some employees' inability to reach work sites.
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. Review contingency plans and be prepared to move quickly to shelter if tornado warnings are issued. Charge battery-powered devices in the case of prolonged electricity outages.
