Flash Flood in Rockingham County, New Hampshire

A coastal front was established along coastal Rockingham County that became the focus for localized moderate to heavy rain through the morning hours of January 13th. The increased rainfall rates with rainfall totals of 2 inches on already saturated ground led to rapid runoff of small streams and rivers along coastal watersheds. The freshwater run-off coincided with the historical storm tide water levels not allowing for water to drain into the oceans. This interaction led to flash flooding at the time of high tide, causing numerous low lying back-bay areas to flood, along with streams crossing roads at the intersection with tidal areas. Flooding of this variety was reported across all coastal Rockingham County towns. Numerous swift water rescues already occurred at this time with motorists being stranded in their vehicles.

The second severe storm in a week's time struck the northern New England coastline during the middle of January. An intense and rapidly deepening area of low pressure over the Great Lakes region (979 mb) combined the highest astronomical tides of the month to produce extreme flooding along the coast. Portland had its all-time storm tide, posting a record flood water level (records 1912-present). The Hampton tide gage also recorded its highest water level since records began in 2012. Storm force southeasterly winds occurred along the coast with nearshore waves of 15 to 20 feet. A flash flood warning was issued for the Seacoast prior to high tide due to rapidly rising ocean water and fresh waters as heavy rain accompanied a coastal front just prior to high tide.