Alert archive / New Hampshire / Flash Flood Warnings in 2025

Flash Flood Warning 7, NWS Gray, ME

August 13, 2025Hillsborough County, Rockingham County, New Hampshire

NWS Gray, ME issued this flash flood warning at Aug 13, 2025, 7:09 PM EDT for Hillsborough County, Rockingham County, New Hampshire. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Aug 13, 2025, 7:09 PM EDT (23:09 UTC)
Expired
Aug 13, 2025, 10:15 PM EDT
In force
3 hr
Issued by
NWS Gray, ME
Area
Storm-based polygon
Flood severity
None

Counties Hillsborough County, NH, Rockingham County, NH

The radar

The Boston radar (KBOX), 113 km from the middle of the area, began a volume at 23:12 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Albany, NY (KALY), launched 12:00Z, 11.2 hours before the alert went out and 200 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Albany, NY at 12:00Z on 2025-08-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 722 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Albany, NY at 12:00Z on 2025-08-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 56 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
722 J/kg
Mixed-layer CIN
-110 J/kg
Mixed-layer LCL
1039 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
56 m²/s²
0-3 km storm-relative helicity
41 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.3

Open this sounding in Storm Lab

The office that day

Everything else NWS Gray, ME issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 13, 4:43 PM EDTSevere Thunderstorm WarningGYXHillsborough47 min
Aug 13, 5:02 PM EDTSevere Thunderstorm WarningGYXHillsborough, Merrimack, Rockingham43 min
Aug 13, 5:04 PM EDTSevere Thunderstorm WarningGYXHillsborough, Rockingham41 min
Aug 13, 5:45 PM EDTSevere Thunderstorm WarningGYXHillsborough, Merrimack, Rockingham45 min
Aug 13, 5:53 PM EDTSevere Thunderstorm WarningGYXCheshire, Hillsborough34 min
Aug 13, 5:54 PM EDTSevere Thunderstorm WarningGYXMerrimack, Rockingham, Strafford36 min

Nearby

Flash Flood Warnings in New Hampshire, 2025Every flash flood warning in 2025

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.