US: Threat of flooding likely to persist across parts of the Mid-Atlantic and Northeast regions through at least Jan. 16 /update 2

The threat of flooding is likely to persist across parts of the Mid-Atlantic and Northeast regions through at least Jan. 16. Heavy rainfall in recent days has caused river levels to rise and saturated ground across much of the affected area. Further showers are forecast over the coming days and despite rainfall levels not being as intense as previous rounds of precipitation, with only amounts of 2.5-5 cm (1-2 inches) forecast, flooding concerns are likely to continue across the region.

As of early Jan. 12, 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 parts of the region. The NWS's Weather Prediction Center has warned of a slight risk (level 2 on a four-tier scale) of excessive rainfall across the affected area late Jan. 11-12. 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, strong winds, 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.