Flash Flood — Carroll, New Hampshire

2023-06-28 · near Moultonboro Arpt, Carroll, New Hampshire

Event narrative

Repeated rounds of rainfall between the 26th and 28th saturated the ground, and by the afternoon of the 28th the runoff was rapid and produced flash flooding. Heavy rainfall caused flooding on NH-109, eroded ditches along the side of the road, undermining the edge of the roadway. There was a partial washout of Bald Peak Dr in the area of NH-109.

Wider weather episode

Two rounds of rain moved across the state on June 28th with a weak frontal boundary. Light rain showers pushed through the state during the morning, with the first line of showers and thunderstorms moving into western New Hampshire by midday. This line slowly moved eastward through the early afternoon hours bringing a widespread band of heavy rain of 1 to 2'. As the axis of heavy rain moved into the Lakes Region of New Hampshire, additional storms developed ahead of it. Heavier rainfall amounts fell from Tilton through the Lake Winnipesaukee region into Moultonborough where 2 to 3' of rain fell in less than 2 hours. This band of heavy rain continued to push further north and east by late afternoon into the White Mountains. The localized heaviest rain fell in Jackson and Bartlett New Hampshire where 3 inches of rain fell in 2 hours. An additional line of showers and thunderstorms later in the day dropped additional localized heavy rainfall on areas that just received soaking rain a few hours earlier. One storm dropped an additional 1.5' of rain in less than an hour north of Lebanon, NH.

View location on OpenStreetMap → (43.7569, -71.3396)

Source: NOAA Storm Events Database, event_id 1109502. Narrative written by the NWS forecast office that issued the report.