US: Threat of flooding likely to persist across parts of the Mid-Atlantic and Northeast regions through at least Jan. 11 /update 1

The threat of flooding is likely to persist across parts of the Mid-Atlantic and Northeast regions through at least Jan. 11. An intense storm system currently moving through the area is expected to bring further heavy downpours and strong winds early Jan. 10 before moving into the Atlantic. Although conditions are likely to improve through Jan. 10, flooding may continue to impact the region due to high river levels and saturated soil. Power outages are ongoing across parts of the region due to strong winds overnight Jan. 9-10; more than 147,000 customers are without power across New York, 115,000 across Pennsylvania, and 70,000 across New Jersey as of early Jan. 10.

As of early Jan. 10, the National Weather Service (NWS) has issued flood and coastal flood warnings, watches, and advisories across much of the affected area. High wind warnings and advisories are also in place across much of the region. The NWS's Weather Prediction Center has warned of a moderate risk (level 3 on a four-tier scale) of excessive rainfall across parts of northeastern Maryland, northern Delaware, northern and western New Jersey, southeastern Pennsylvania, central New York, Connecticut, Rhode Island, and southern Massachusetts and a slight risk of excessive rainfall across the rest of the affected area early Jan. 10. Authorities will likely issue new alerts or update/rescind existing advisories as weather conditions change over 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 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 rain has saturated the soil.

Authorities could issue mandatory evacuation orders for flood-prone communities over the coming days. Disruptions to electricity and telecommunications services are possible where significant flooding or landslides impact utility networks.

The severe weather could contribute to transport disruptions throughout the region. Traffic and commercial trucking delays might occur along regional highways. Flooding could inundate some low-lying roads in areas with poor drainage. Strong winds might also pose a hazard to high-profile vehicles. Hazardous weather conditions may cause flight delays and airport cancellations in affected areas. Authorities may temporarily suspend port operations or close beachfronts if strong winds trigger hazardous sea conditions.