On the evening of July 15th isolated thunderstorms developed across southern New Hampshire.  Storm movement mitigated flash flooding across the state, except for the city of Manchester where multiple storms traveled directly over the city on the evening of July 15th.  Up to 2��� fell in an hour over the urban city area.  The intense rainfall rates lead to rapid run-off and caused localized urban street flooding with water due to run-off entering some building structures.  Lighter showers passed across the area later in the evening before rain ended.
On July 16th a more widespread area of rain impacted most of the state.  Rain showers began to develop around daybreak on July 16th and quickly became more widespread during the morning hours.  Light to moderate rainfall became widespread across the state with embedded bands of heavy rain.  Locally heavy rainfall continued straight through the morning hours into early afternoon on the 16th before rainfall intensity and coverage began to decrease.  Central and Southern New Hampshire received the heaviest rainfall through the day, with less rainfall across the Connecticut River Valley and the Seacoast.  Rainfall amounts of 2+��� were widespread across Central New Hampshire with two corridors of locally heavier rain in this area.  One corridor of heavy rain was from eastern Cheshire County through northwest Hillsborough County and into Central Merrimack County.  Observed reports of 3+��� of rain occurred in this region with one localized report of 4+���.  The heavy rain caused isolated areas of flooded roads along with wash-outs in Antrim where a localized area of heavy rain occurred.  The second corridor of heavy rain across the state was the most significant for the event.  This corridor of rain ran from the Massachusetts border around Nashua all the way to the Maine border in southern Carroll County.  There were numerous reports of 3+��� of rain with localized areas receiving over 4��� of rainfall by early afternoon.  The majority of this rainfall fell in a 3 to 4 hour window in the late morning hours.  The heavy rainfall rates and saturated grounds led to rapid run-off of small streams and creeks which led to flash flooding.  Flash flooding was considerable in the Barnstead, Alton and Wolfeboro region where numerous roads were closed due to severe flooding and wash-outs.  Additional urban flash flooding also occurred in the Manchester area due to flooded roads.  Minor property flooding was also reported on numerous lakefronts across the region due to very high lake levels after this rain event.
Localized river flooding also occurred in response to the July 15-16th rainfall with river flooding beginning on July 16th and lasting through the 18th, with river crests occurring on July 17th.  The Warner River touched minor flood stage with no significant impacts.  The Suncook River crested at 3.53ft above flood stage on July 17th.  This led to flooding of campgrounds along the river that caused the evacuation of at least one located in the floodplain. All rivers dropped below flood stage on July 18th.
In addition to the flooding, the environment supported a conditional threat for severe weather as the abundant low level moisture and strong low level jet caused significant low level shear.  This caused for numerous storms to have rotation with them that triggered tornado warnings but no tornadoes were confirmed.  There was however some localized tree damage with the associated thunderstorms across Southern New Hampshire.

Thunderstorm Wind in ROCKINGHAM, NEW HAMPSHIRE
From 16-JUL-23 09:00:00 to 16-JUL-23 09:05:00 (EST-5)
Location: NOTTINGHAM SQUARE
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Utility Company

Severe thunderstorm outflow winds downed numerous branches along with a few trees and wires in Nottingham.

Flash Flood in BELKNAP, NEW HAMPSHIRE
From 16-JUL-23 12:10:00 to 16-JUL-23 13:40:00 (EST-5)
Location: ALTON
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Severe flooding reported across Alton after 4 to 7 inches of rain fell on the 16th. Ground conditions were saturated ahead of this event due to multiple heavy rain events the weeks prior to the flooding. The hardest hit areas were in central and southern Alton where several areas were impassable due to damaged roads. Flooding caused flooding of NH-140 near Gilmanton Fire Department. Numerous washouts were reported on Mount Major Highway. Jesus Valley Road was undermined due to an undersized culvert.
The most devastating damages occurred on NH-140 near Elliot Road. A small brook coming out of Meadow Dam Pond flows southeast towards Elliot Road and Route 140. This brook produced significant flooding and undermined a hundred yard stretch of Route 140 and damaged several properties.

Flash Flood in CARROLL, NEW HAMPSHIRE
From 16-JUL-23 16:28:00 to 16-JUL-23 17:00:00 (EST-5)
Location: (8B8)WOLFEBORO ARPT
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Heavy rain caused a washout on South Main Street in Wolfboro.

Flood in MERRIMACK, NEW HAMPSHIRE
From 17-JUL-23 12:45:00 to 18-JUL-23 12:00:00 (EST-5)
Location: NORTH CHICHESTER
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Heavy rains on July 16th lead to flooding along the Suncook River. The USGS river gage in North Chichester crested at 10.5 feet on the 17th. The flood stage is 7 feet, and the river crested at the minor flood level. The impacts were most notable at the Lazy River Campground where water inundated campsites with 2 to 3 feet of water. Numerous campers had to be evacuated. Water came out of banks in Allenstown, but did not, but did not cause any property damage.

Flood in CARROLL, NEW HAMPSHIRE
From 16-JUL-23 02:00:00 to 17-JUL-23 19:00:00 (EST-5)
Location: NORTH CONWAY
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Other Federal Agency

The Saco River came out of banks on July 16th following heavy rain showers. The USGS river gage at Conway exceeded the flood stage of 9 feet, cresting at 8.3 feet on the 16th. The impacts were mainly focused at low lying campgrounds and flooding at Transvale Road.

Thunderstorm Wind in ROCKINGHAM, NEW HAMPSHIRE
From 16-JUL-23 08:45:00 to 16-JUL-23 08:50:00 (EST-5)
Location: AUBURN
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Amateur Radio

Severe thunderstorm outflow winds downed trees around Lake Massabesic in Manchester.

Flash Flood in CARROLL, NEW HAMPSHIRE
From 16-JUL-23 15:07:00 to 16-JUL-23 15:30:00 (EST-5)
Location: WOLFEBORO
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Heavy rain caused a washout on NH-109 in Wolfboro.

Flash Flood in HILLSBOROUGH, NEW HAMPSHIRE
From 15-JUL-23 17:35:00 to 15-JUL-23 19:00:00 (EST-5)
Location: MASSABESIC
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Airplane Pilot

Heavy rain moved into the Manchester area on the afternoon of the 15th. Urban runoff occurred after rainfall rates of 2 to 4 inches per hour fell. Numerous roads were closed due to flooding including Lake Avenue in the 500-block area with water entering a residence basement. Valley Street in the area of Belmont street was also closed due to flooding.

Flash Flood in GRAFTON, NEW HAMPSHIRE
From 15-JUL-23 22:30:00 to 15-JUL-23 23:30:00 (EST-5)
Location: LINCOLN
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Heavy rainfall with rainfall rates between 2 and 4 inches per hours caused flooding and minor debris slide in Lincoln on the evening of the 15th. A debris flow was reported on Pinehill Lane and Charkarohen Drive closing the road and cutting off homes. Some minor property damage of yards.

Flash Flood in HILLSBOROUGH, NEW HAMPSHIRE
From 16-JUL-23 10:20:00 to 16-JUL-23 10:30:00 (EST-5)
Location: ANTRIM
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Heavy rainfall with rates between 2 and 4 inches per hour fell over Antrim on the morning of the 16th. All lanes were closed on Washington Road from Center Road to Robbins Road due to flooding.

Flash Flood in MERRIMACK, NEW HAMPSHIRE
From 16-JUL-23 10:00:00 to 16-JUL-23 11:00:00 (EST-5)
Location: DANBURY
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

North Road in Danbury damaged after flooding caused part of the road collapsed near School Pond Road.

Flash Flood in CARROLL, NEW HAMPSHIRE
From 16-JUL-23 11:31:00 to 16-JUL-23 13:30:00 (EST-5)
Location: MADISON
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Heavy rain between 2 to 5 inches fell across the Madison area. Runoff caused the full road closure of Rt 113.

Flash Flood in HILLSBOROUGH, NEW HAMPSHIRE
From 16-JUL-23 10:44:00 to 16-JUL-23 15:00:00 (EST-5)
Location: ANTRIM
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Heavy rain caused numerous road closures across Antrim. Whitney Road, Old Concord Road, Old Turnpike Road, Upper Pleasant Street. and more. On West St. On Buttercup Lane a culvert failed, and a section of roadway was damaged.

Flash Flood in MERRIMACK, NEW HAMPSHIRE
From 16-JUL-23 11:51:00 to 16-JUL-23 13:00:00 (EST-5)
Location: SOUTH HOOKSETT
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Flooding in South Hooksett prompted a full closure of NH-28A.

Flash Flood in HILLSBOROUGH, NEW HAMPSHIRE
From 16-JUL-23 10:42:00 to 16-JUL-23 14:00:00 (EST-5)
Location: MILFORD
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Heavy rain promoted renewed flooding in the Milford area after a period of frequent heavy rains across the state. By late morning of the 11th, flooding caused the closure of Route 101A in Milford from the Route 101 exit ramp to the downtown Milford area. One minor area of flowing water from a nearby swamp is crossing the road on Tonella Road.

Flash Flood in BELKNAP, NEW HAMPSHIRE
From 16-JUL-23 11:50:00 to 16-JUL-23 12:50:00 (EST-5)
Location: CENTER BARNSTEAD
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Heavy rain caused a wash-out on White Oak Road.

Flash Flood in HILLSBOROUGH, NEW HAMPSHIRE
From 16-JUL-23 10:00:00 to 16-JUL-23 10:30:00 (EST-5)
Location: HILLSBORO CENTER
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Bear Brook overflowed its banks after heavy rains moved into the state on the morning of the 16th. The brook was already running at bankfull prior to the storms arrival. The extra 1 to 3 inches of rain was sufficient to cause it to come out of banks and flood East Washington Road.

Flash Flood in HILLSBOROUGH, NEW HAMPSHIRE
From 16-JUL-23 10:15:00 to 16-JUL-23 10:30:00 (EST-5)
Location: MANCHESTER
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Heavy rain measured between 2 to 4 inches fell across the City of Manchester. Urban flooding was reported including the full closure of Commercial St in Manchester.

Flash Flood in BELKNAP, NEW HAMPSHIRE
From 16-JUL-23 13:30:00 to 16-JUL-23 14:45:00 (EST-5)
Location: (LCI)LACONIA ARPT
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Heavy rain between 3 and 5 inches caused a large sinkhole on Cherry Valley Road, cutting off some residents.

Flash Flood in BELKNAP, NEW HAMPSHIRE
From 16-JUL-23 13:43:00 to 16-JUL-23 15:00:00 (EST-5)
Location: BARNSTEAD
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Heavy rain between 3 and 5 inches caused multiple washouts on Will Smith Road, cutting off some residents.

Flash Flood in BELKNAP, NEW HAMPSHIRE
From 16-JUL-23 16:20:00 to 16-JUL-23 17:00:00 (EST-5)
Location: BARNSTEAD
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Heavy rain between 3 and 5 inches caused a washout on Vail Road.

Flash Flood in CARROLL, NEW HAMPSHIRE
From 16-JUL-23 16:00:00 to 16-JUL-23 17:00:00 (EST-5)
Location: SOUTH WOLFEBORO
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

Heavy rain caused Route 28 in Wolfboro to wash-out between the Belknap and Carroll County line.