High Wind — Southern Grafton, New Hampshire
2017-10-30 · Southern Grafton, New Hampshire
Wider weather episode
New Hampshire Weather and Hydrological Summary
October 29-November 1, 2017
National Weather Service Offices
Gray, Maine
An area of low pressure over the southeastern United States on the morning of Sunday, October 29th, intensified rapidly Sunday night and Monday, October 30, as it moved northward and moisture and energy from the remnants of Tropical Storm Philippe merged with the storm. The combined system brought high winds to much of New Hampshire Sunday night into Monday morning, with the highest winds in southern and central sections of the State. In addition, heavy rain accompanied the high winds over New Hampshire leading to both flash flooding and main-stem river flooding. The highest rainfall amounts were observed in the White Mountains. While the high winds and heavy rain ended during the morning of the 30th, flooding persisted into the late afternoon of November 1st.
The area from Carroll County through Hillsborough County had the greatest impact from the high winds. Numerous trees were snapped and uprooted by the strong southeast winds leading to widespread and prolonged power outages throughout the area. Wet soil conditions, due to heavy rains days earlier, may have contributed to the vulnerability of the many shallow rooted trees. Observed wind gusts across the hardest hit areas generally ranged from 55 to 60 mph, although some areas likely had wind gusts in excess of 65 mph. Some official reporting sites included Manchester (59 mph), Whitefield (58 mph), Portsmouth (56 mph), Rochester (56 mph), Concord (51 mph), and Berlin (51 mph). Several unofficial sites reported stronger wind gusts. Wind gusts in the coastal marine areas ranged up to more than 80 mph.
Rainfall amounts generally ranged from 2 to 5 inches across New Hampshire. Most of this rain fell within a 10-hour period from late Sunday evening through early Monday morning. Some of the higher official amounts include Livermore (6.91 inches), Berlin (5.23 inches), Gorham (5.13 inches), Waterville Valley (5.07 inches), Lyndeborough (5.06 inches), Pinkham Notch (5.05 inches), and Lincoln (5.05 inches). The heavy rain caused flash flooding in Grafton, Carroll, and Coos Counties and main-stem river flooding on the Androscoggin, Baker, Contoocook, Pemigewasset, Piscataquog, Saco, Smith, Souhegan, Suncook, and Warner Rivers.
By Wednesday evening, November 1st, all flooding had subsided. Power restoration efforts in the hardest hit areas across New Hampshire persisted for much of the week.
Source: NOAA Storm Events Database, event_id 725149. Narrative written by the NWS forecast office that issued the report.