Alert archive / New Hampshire / Flash Flood Warnings in 2023

Flash Flood Warning 45, NWS Gray, ME

July 16, 2023Cheshire County, Hillsborough County, New Hampshire

NWS Gray, ME issued this flash flood warning at Jul 16, 2023, 7:33 AM EDT for Cheshire County, Hillsborough County, New Hampshire. It was in force for 4 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
Jul 16, 2023, 7:33 AM EDT (11:33 UTC)
Expired
Jul 16, 2023, 11:30 AM EDT
In force
4 hr
Issued by
NWS Gray, ME
Area
Storm-based polygon
Flood severity
None

Counties Cheshire County, NH, Hillsborough County, NH

The radar

The Boston radar (KBOX), 127 km from the middle of the area, began a volume at 11:33 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

Brookhaven, NY (KOKX), launched 00:00Z, 11.6 hours before the alert went out and 239 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, Brookhaven, NY at 00:00Z on 2023-07-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1061 joules per kilogram.LCLEL10008507005003002001001 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, Brookhaven, NY at 00:00Z on 2023-07-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 63 square meters per square second.193958Sfc1 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
1061 J/kg
Mixed-layer CIN
-2 J/kg
Mixed-layer LCL
624 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
63 m²/s²
0-3 km storm-relative helicity
29 m²/s²
Significant tornado parameter
0.2
Supercell composite
2.0

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 Jul 16, 4:12 AM EDT, 3 hours 21 minutes earlier.

Area forecast discussion, Jul 16, 4:12 AM EDT, 3 hours 21 minutes before
<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>
Hazardous weather outlook, Jul 16, 3:56 AM EDT, 3 hours 37 minutes before
<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

In the hours before

Special weather statement, Jul 16, 7:18 AM EDT, 15 minutes before
Special Weather Statement
National Weather Service Gray ME
718 AM EDT Sun Jul 16 2023

MEZ007-012-013-018>022-024>027-033-NHZ002>006-161200-
Northern Oxford ME-Interior Cumberland Highlands ME-Kennebec ME-
Central Interior Cumberland ME-Coastal Cumberland ME-Sagadahoc ME-
Southern Oxford ME-Androscoggin ME-Interior York ME-
Interior Waldo ME-Southern Franklin ME-Lincoln ME-Knox ME-
Southern Coos NH-Northern Carroll NH-Northern Grafton NH-
Southern Carroll NH-Southern Grafton NH-
718 AM EDT Sun Jul 16 2023

...A line of heavy rain moving northeast will impact portions of
Oxford, west central Waldo, Androscoggin, southeastern Franklin,
Kennebec, northwestern Knox, north central York, Lincoln,
Cumberland, Sagadahoc, southern Coos, northeastern Grafton and
northern Carroll Counties through 800 AM EDT...

HAZARD...Torrential rain with rainfall rates over 2 inches per hour.
         This will reduce visibility and could cause hydroplaning
         for motorists. More rain is expected throughout the day
         which could result in flash floods as repeating shower
         activity is expected. Please stay tuned to the latest
         warnings from the National Weather Service.

SOURCE...Radar indicated.

IMPACT...Use caution if traveling through into this drenching
         rainfall. Visibility will drop to under a quarter of an
         inch cause rapid ponding on roadways and low lying areas.

Locations impacted include...
Lewiston, Auburn, Brunswick, Augusta, Westbrook, Waterville, Conway,
Berlin, Bath, Gardiner, Bridgton, Lancaster, Fryeburg, Mechanic
Falls, Bethel, Bethlehem, Damariscotta, Lincoln, Naples and Oakland.

This includes the following highways...
 Interstate 295 between mile markers 12 and 51.
 Interstate 93 between mile markers 86 and 114.
 Interstate 95 between mile markers 54 and 128.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 4466 7142 4454 6933 4380 6951 4372 6956
      4375 6969 4370 6973 4386 7193
TIME...MOT...LOC 1114Z 240DEG 49KT 4398 7142

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...<30 MPH

SJ

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 15, 8:02 PM EDTAreal Flood AdvisoryGYXSomerset6 hr
Jul 15, 8:59 PM EDTAreal Flood AdvisoryGYXOxford3 hr
Jul 16, 7:18 AM EDTSpecial Weather StatementGYXAndroscoggin, Cumberland, Kennebec, Lincoln, Oxford, Sagadahoc42 min
Jul 16, 8:14 AM EDTFlash Flood WarningGYXYork4 hr
Jul 16, 12:18 PM EDTRiver Flood WarningGYXCumberland, Oxford25 hr
Jul 16, 12:31 PM EDTFlash Flood WarningGYXCumberland, Oxford5 hr
Jul 16, 12:37 PM EDTSpecial Marine WarningGYX53 min
Jul 16, 1:19 PM EDTAreal Flood WarningGYXCumberland, Oxford, York5 hr
Jul 16, 2:22 PM EDTFlash Flood Warning Considerable damage threatGYXCumberland, Oxford, York6 hr
Jul 16, 2:42 PM EDTFlash Flood Warning Considerable damage threatGYXCumberland, Oxford3 hr
Jul 16, 4:02 PM EDTAreal Flood WarningGYXAndroscoggin, Franklin, Kennebec, Oxford, Somerset, Waldo6 hr
Jul 16, 4:04 PM EDTRiver Flood WarningGYXOxford19 hr
Jul 16, 6:16 PM EDTAreal Flood WarningGYXCumberland, Oxford, York11 hr
Jul 15, 9:28 PM EDTAreal Flood AdvisoryGYXGrafton3 hr
Jul 15, 9:46 PM EDTFlash Flood WarningGYXGrafton3 hr
Jul 16, 8:21 AM EDTSpecial Weather StatementGYXRockingham24 min
Jul 16, 8:22 AM EDTFlash Flood Warning Considerable damage threatGYXHillsborough, Merrimack, Rockingham3 hr
Jul 16, 8:29 AM EDTTornado WarningGYXHillsborough, Merrimack, Rockingham31 min
Jul 16, 9:01 AM EDTTornado WarningGYXHillsborough, Rockingham16 min
Jul 16, 9:34 AM EDTSevere Thunderstorm WarningGYXRockingham41 min
Jul 16, 9:51 AM EDTTornado WarningGYXRockingham, Strafford24 min
Jul 16, 10:16 AM EDTTornado WarningGYXHillsborough29 min
Jul 16, 10:32 AM EDTFlash Flood WarningGYXBelknap, Carroll, Coos, Grafton, Merrimack, Strafford6 hr
Jul 16, 11:24 AM EDTFlash Flood Warning Considerable damage threatGYXBelknap, Cheshire, Hillsborough, Merrimack, Rockingham7 hr
Jul 16, 11:33 AM EDTFlash Flood WarningGYXBelknap, Carroll, Merrimack, Strafford6 hr
Jul 16, 11:39 AM EDTAreal Flood WarningGYXCheshire, Hillsborough, Merrimack, Sullivan6 hr
Jul 16, 12:19 PM EDTRiver Flood WarningGYXGrafton7 hr
Jul 16, 1:01 PM EDTFlash Flood Warning Considerable damage threatGYXBelknap, Carroll, Strafford5 hr
Jul 16, 2:16 PM EDTRiver Flood WarningGYXBelknap, Merrimack49 hr
Jul 16, 4:33 PM EDTAreal Flood AdvisoryGYXCarroll6 hr
Jul 16, 6:03 PM EDTAreal Flood WarningGYXBelknap, Merrimack12 hr
Jul 16, 7:30 PM EDTRiver Flood WarningGYXMerrimack10 hr

Nearby

Flash Flood Warnings in New Hampshire, 2023Every flash flood warning in 2023

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.