22 Apr 2022 | 07:21 AM UTC
US: Adverse weather forecast across the South, Northern Rockies and Plains, Upper Midwest, Ohio Valley regions through at least early April 24 /update 2
Adverse weather forecast across southern and central regions in the US through at least early April 24. Tornadoes possible.
Event
Severe weather is forecast across portions of parts of the South, Northern Rockies and Plains, Upper Midwest, and Ohio Valley regions through at least early April 24. Thunderstorms will likely be accompanied by heavy rainfall, strong winds, hail storms, and possible tornadoes.
The storms will likely impact many of the same areas of the southern and central US hit by severe thunderstorms in late March. Reports indicate 81 tornadoes occurred across Texas, Oklahoma, Louisiana, Mississippi, southern Alabama, and northwestern Florida March 21-23 and 40 tornadoes across the Midwest March 25. The tornadoes caused widespread damage to property and resulted in power outages impacting thousands. Additional rainfall over already saturated ground is likely to result in floods and flash floods.
Government Advisories
As of early April 22, the National Weather Service (NWS) has issued severe thunderstorm warnings across eastern Nebraska and far western Iowa. Authorities will likely issue watches and warnings over the coming hours and days as the storm progresses.
The NWS's Storm Prediction Center has warned of an "Enhanced Risk" (Level 3 on a five tier-scale) of severe thunderstorms across parts of northwestern Texas, western Oklahoma, western Kansas, and central Nebraska April 22, with the slight risk warning area surrounding the enhanced risk warning area, from northwestern Texas northwards into far southern North Dakota, far southwestern Minnesota, and far southeastern Montana. A "Slight Risk" is in place across much of Minnesota, far western Wisconsin, Iowa, far southeastern Nebraska, northwestern Missouri, eastern Kansas, and central Oklahoma April 23 through early April 24.
Severe storms in the "Enhanced Risk" (Level 3) regions are forecast to be more numerous, persistent, and widespread than those in the region where a "Slight Risk" (Level 2) has been issued. Storms in the Slight Risk regions are not forecast to be widespread or long-lived. Isolated intense storms are possible; however, widespread damage is unlikely. Isolated intense storms are possible, which may contain hail, damaging winds, and a few tornadoes.
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, as well as 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 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.
Severe weather could also trigger flight delays and cancellations at airports in the 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.
