Alert archive / New Hampshire / Flash Flood Warnings in 2020

Flash Flood Warning 24, NWS Gray, ME

August 24, 2020Hillsborough County, Rockingham County, New Hampshire

NWS Gray, ME issued this flash flood warning at Aug 24, 2020, 4:36 PM EDT for Hillsborough County, Rockingham County, New Hampshire. It was in force for 50 min. 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 24, 2020, 4:36 PM EDT (20:36 UTC)
Expired: Aug 24, 2020, 5:26 PM EDT
In force: 50 min
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 20:36 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

Chatham, MA (KCHH), launched 12:00Z, 8.6 hours before the alert went out and 185 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1029 J/kg
Mixed-layer CIN: -70 J/kg
Mixed-layer LCL: 662 m above ground
0-6 km bulk shear: 20 kt
0-1 km storm-relative helicity: 32 m²/s²
0-3 km storm-relative helicity: 62 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Gray, ME wrote its last area forecast discussion before this flash flood warning went out at Aug 24, 3:32 PM EDT, 1 hour 4 minutes earlier.

Area forecast discussion, Aug 24, 3:32 PM EDT, 1 hour 4 minutes before

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Hazardous weather outlook, Aug 24, 3:28 PM EDT, 1 hour 8 minutes before

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In the hours before

Local storm report, Aug 24, 3:56 PM EDT, 40 minutes before

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Local storm report, Aug 24, 4:07 PM EDT, 29 minutes before

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Local storm report, Aug 24, 4:11 PM EDT, 25 minutes before

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Local storm report, Aug 24, 4:13 PM EDT, 23 minutes before

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Special weather statement, Aug 24, 4:17 PM EDT, 19 minutes before

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Local storm report, Aug 24, 4:34 PM EDT, 2 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 24, 12:55 PM EDT	Special Weather Statement	GYX	Oxford	35 min
Aug 24, 1:06 PM EDT	Severe Thunderstorm Warning	GYX	Franklin, Oxford	39 min
Aug 24, 1:20 PM EDT	Special Weather Statement	GYX	Kennebec	25 min
Aug 24, 1:27 PM EDT	Severe Thunderstorm Warning	GYX	Somerset	48 min
Aug 24, 1:36 PM EDT	Special Weather Statement	GYX	Kennebec	24 min
Aug 24, 1:38 PM EDT	Severe Thunderstorm Warning	GYX	Androscoggin, Franklin, Oxford	52 min
Aug 24, 1:45 PM EDT	Severe Thunderstorm Warning	GYX	Franklin, Somerset	45 min
Aug 24, 2:04 PM EDT	Severe Thunderstorm Warning	GYX	Franklin, Kennebec	45 min
Aug 24, 2:16 PM EDT	Severe Thunderstorm Warning	GYX	Kennebec, Somerset	44 min
Aug 24, 2:55 PM EDT	Special Weather Statement	GYX	Waldo	50 min
Aug 24, 3:14 PM EDT	Severe Thunderstorm Warning	GYX	Kennebec, Lincoln	46 min
Aug 24, 3:30 PM EDT	Small Craft Advisory	GYX		54 hr
Aug 24, 3:38 PM EDT	Severe Thunderstorm Warning	GYX	Cumberland, Oxford	52 min
Aug 24, 3:48 PM EDT	Special Weather Statement	GYX	Androscoggin	57 min
Aug 24, 3:50 PM EDT	Severe Thunderstorm Warning	GYX	Kennebec, Knox, Lincoln	40 min
Aug 24, 4:06 PM EDT	Severe Thunderstorm Warning	GYX	Cumberland	54 min
Aug 24, 4:17 PM EDT	Special Weather Statement	GYX	Androscoggin	58 min
Aug 24, 4:21 PM EDT	Severe Thunderstorm Warning	GYX	Androscoggin, Cumberland, Oxford	39 min
Aug 24, 4:51 PM EDT	Severe Thunderstorm Warning	GYX	Androscoggin, Cumberland	39 min
Aug 24, 4:57 PM EDT	Severe Thunderstorm Warning	GYX	Cumberland	48 min
Aug 24, 5:04 PM EDT	Areal Flood Advisory	GYX	Cumberland	56 min
Aug 24, 5:25 PM EDT	Special Weather Statement	GYX	Sagadahoc	65 min
Aug 24, 5:32 PM EDT	Special Weather Statement	GYX	Cumberland	28 min
Aug 24, 5:44 PM EDT	Special Weather Statement	GYX	Cumberland	46 min
Aug 24, 5:46 PM EDT	Special Weather Statement	GYX	Kennebec	29 min
Aug 24, 5:58 PM EDT	Special Weather Statement	GYX	Cumberland	47 min
Aug 24, 6:14 PM EDT	Severe Thunderstorm Warning	GYX	Androscoggin, Cumberland	17 min
Aug 24, 6:29 PM EDT	Special Weather Statement	GYX	Lincoln	46 min
Aug 24, 6:54 PM EDT	Special Weather Statement	GYX	Cumberland	51 min
Aug 23, 8:04 PM EDT	Special Weather Statement	GYX	Cheshire	41 min
Aug 23, 8:16 PM EDT	Severe Thunderstorm Warning	GYX	Cheshire	26 min
Aug 23, 8:31 PM EDT	Areal Flood Advisory	GYX	Cheshire	76 min
Aug 23, 8:37 PM EDT	Special Weather Statement	GYX	Cheshire, Sullivan	38 min
Aug 23, 8:40 PM EDT	Severe Thunderstorm Warning	GYX	Grafton, Sullivan	50 min
Aug 23, 9:14 PM EDT	Special Weather Statement	GYX	Sullivan	46 min
Aug 23, 9:31 PM EDT	Special Weather Statement	GYX	Grafton	44 min
Aug 23, 9:58 PM EDT	Special Weather Statement	GYX	Merrimack	47 min
Aug 23, 10:17 PM EDT	Special Weather Statement	GYX	Sullivan	58 min
Aug 23, 10:19 PM EDT	Special Weather Statement	GYX	Grafton	41 min
Aug 23, 10:32 PM EDT	Special Weather Statement	GYX	Rockingham	58 min
Aug 23, 10:41 PM EDT	Special Weather Statement	GYX	Grafton	49 min
Aug 23, 10:48 PM EDT	Areal Flood Advisory	GYX	Merrimack, Sullivan	117 min
Aug 23, 10:57 PM EDT	Special Weather Statement	GYX	Carroll	48 min
Aug 24, 2:33 PM EDT	Special Weather Statement	GYX	Sullivan	42 min
Aug 24, 2:36 PM EDT	Special Weather Statement	GYX	Cheshire	24 min
Aug 24, 2:38 PM EDT	Severe Thunderstorm Warning	GYX	Cheshire	33 min
Aug 24, 3:24 PM EDT	Special Weather Statement	GYX	Carroll	51 min
Aug 24, 3:38 PM EDT	Severe Thunderstorm Warning	GYX	Hillsborough, Merrimack, Rockingham	52 min
Aug 24, 3:41 PM EDT	Special Weather Statement	GYX	Rockingham	49 min
Aug 24, 3:54 PM EDT	Severe Thunderstorm Warning	GYX	Hillsborough, Rockingham	25 min
Aug 24, 4:18 PM EDT	Severe Thunderstorm Warning	GYX	Hillsborough, Rockingham	57 min
Aug 24, 4:23 PM EDT	Areal Flood Advisory	GYX	Hillsborough, Rockingham	3 hr
Aug 24, 4:42 PM EDT	Special Weather Statement	GYX	Coos, Grafton	48 min
Aug 24, 5:08 PM EDT	Special Weather Statement	GYX	Coos	37 min
Aug 24, 5:26 PM EDT	Areal Flood Advisory	GYX	Hillsborough, Rockingham	2 hr
Aug 24, 5:29 PM EDT	Special Weather Statement	GYX	Carroll	61 min
Aug 24, 6:04 PM EDT	Special Weather Statement	GYX	Merrimack	41 min
Aug 24, 6:29 PM EDT	Severe Thunderstorm Warning	GYX	Merrimack, Rockingham	13 min

Nearby

Flash Flood Warnings in New Hampshire, 2020 Every flash flood warning in 2020

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.