Alert archive / New Jersey / Areal Flood Advisories in 2020

Areal Flood Advisory 116, NWS Philadelphia/Mount Holly

August 4, 20207 counties in New Jersey; 5 counties in Pennsylvania; New Castle County, Delaware

NWS Philadelphia/Mount Holly issued this areal flood advisory at Aug 4, 2020, 5:17 AM EDT for 7 counties in New Jersey; 5 counties in Pennsylvania; New Castle County, Delaware. It was in force for 4 hr.

The area

The counties it named.

The facts

Issued: Aug 4, 2020, 5:17 AM EDT (09:17 UTC)
Expired: Aug 4, 2020, 9:15 AM EDT
In force: 4 hr
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

Counties New Castle County, DE, Burlington County, NJ, Camden County, NJ, Gloucester County, NJ, Hunterdon County, NJ, Mercer County, NJ, Salem County, NJ, Somerset County, NJ, Bucks County, PA, Chester County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 62 km from the middle of the area, began a volume at 09:19 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, 9.3 hours before the alert went out and 213 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: 560 J/kg
Mixed-layer CIN: -65 J/kg
Mixed-layer LCL: 1172 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 54 m²/s²
0-3 km storm-relative helicity: 83 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 1.5

Open this sounding in Storm Lab

What forecasters said that day

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

NWS Philadelphia/Mount Holly wrote its last area forecast discussion before this areal flood advisory went out at Aug 4, 3:46 AM EDT, 1 hour 31 minutes earlier.

Area forecast discussion, Aug 4, 3:46 AM EDT, 1 hour 31 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, Aug 4, 2:44 AM EDT, 2 hours 33 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

Local storm report, Aug 4, 12:20 AM EDT, 4 hours 57 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>

Local storm report, Aug 4, 12:30 AM EDT, 4 hours 47 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>

Local storm report, Aug 4, 12:40 AM EDT, 4 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>

Local storm report, Aug 4, 12:45 AM EDT, 4 hours 32 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>

Local storm report, Aug 4, 12:49 AM EDT, 4 hours 28 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>

Local storm report, Aug 4, 1:04 AM EDT, 4 hours 13 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>

The office that day

Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 3, 8:07 PM EDT	Special Weather Statement	PHI	Hunterdon, Somerset, Warren	23 min
Aug 3, 8:26 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Middlesex, Morris, Somerset	34 min
Aug 3, 9:02 PM EDT	Special Weather Statement	PHI	Morris	28 min
Aug 4, 5:55 AM EDT	Special Marine Warning	PHI		21 min
Aug 4, 7:28 AM EDT	Flash Flood Warning	PHI	Gloucester, Salem	3 hr
Aug 4, 8:38 AM EDT	Special Marine Warning	PHI		52 min
Aug 4, 9:16 AM EDT	Tornado Warning	PHI	Cumberland	18 min
Aug 4, 9:28 AM EDT	Special Marine Warning	PHI		32 min
Aug 4, 9:31 AM EDT	Special Marine Warning	PHI		59 min
Aug 4, 9:42 AM EDT	Tornado Warning	PHI	Atlantic, Cape May	19 min
Aug 4, 10:02 AM EDT	Flash Flood Warning	PHI	Gloucester, Salem	4 hr
Aug 4, 10:15 AM EDT	Tornado Warning	PHI	Atlantic, Burlington, Ocean	14 min
Aug 4, 10:20 AM EDT	Flash Flood Warning	PHI	Burlington, Camden, Gloucester	4 hr
Aug 4, 11:00 AM EDT	Tornado Warning Tornado observed	PHI	Monmouth, Ocean	11 min
Aug 4, 11:01 AM EDT	Flash Flood Warning	PHI	Burlington, Hunterdon, Mercer, Middlesex, Monmouth, Ocean and 1 more	4 hr
Aug 4, 11:13 AM EDT	Areal Flood Advisory	PHI	Sussex, Warren	4 hr
Aug 4, 11:43 AM EDT	Flash Flood Warning	PHI	Warren	4 hr
Aug 4, 11:59 AM EDT	Areal Flood Advisory	PHI	Hunterdon, Middlesex, Monmouth, Morris, Somerset	4 hr
Aug 4, 2:33 PM EDT	River Flood Warning	PHI	Hunterdon, Somerset	5 hr
Aug 4, 2:47 PM EDT	Areal Flood Warning	PHI	Hunterdon, Mercer, Middlesex, Somerset, Warren	9 hr
Aug 4, 3:42 PM EDT	Areal Flood Warning	PHI	Warren	4 hr
Aug 4, 4:37 PM EDT	Areal Flood Warning	PHI	Cumberland, Salem	10 hr
Aug 4, 5:04 PM EDT	Small Craft Advisory	PHI		14 hr
Aug 4, 5:30 PM EDT	Coastal Flood Statement	PHI	Ocean	103 min
Aug 4, 7:23 AM EDT	Tornado Warning	PHI	Chester, Delaware, Montgomery, Philadelphia	20 min
Aug 4, 8:11 AM EDT	Flash Flood Warning	PHI	Bucks, Lehigh, Montgomery, Northampton	4 hr
Aug 4, 8:19 AM EDT	River Flood Warning	PHI	Delaware	15 hr
Aug 4, 8:19 AM EDT	Tornado Warning	PHI	Bucks	26 min
Aug 4, 9:23 AM EDT	Tornado Warning Tornado observed	PHI	Chester	22 min
Aug 4, 9:29 AM EDT	Tornado Warning	PHI	Monroe, Northampton	31 min
Aug 4, 9:38 AM EDT	Flash Flood Warning	PHI	Monroe, Northampton	4 hr
Aug 4, 9:58 AM EDT	Tornado Warning	PHI	Monroe	16 min
Aug 4, 10:51 AM EDT	Tornado Warning	PHI	Montgomery	24 min
Aug 4, 12:06 PM EDT	River Flood Warning	PHI	Chester	11 hr
Aug 4, 12:37 PM EDT	River Flood Warning	PHI	Montgomery	14 hr
Aug 4, 12:48 PM EDT	River Flood Warning	PHI	Chester, Delaware	24 hr
Aug 4, 1:01 PM EDT	River Flood Warning	PHI	Bucks	18 hr
Aug 4, 1:12 PM EDT	River Flood Warning	PHI	Berks	10 hr
Aug 4, 1:12 PM EDT	River Flood Warning	PHI	Montgomery	26 hr
Aug 4, 1:12 PM EDT	River Flood Warning	PHI	Chester, Montgomery, Philadelphia	43 hr
Aug 4, 1:12 PM EDT	River Flood Warning	PHI	Montgomery, Philadelphia	35 hr
Aug 4, 1:59 PM EDT	Areal Flood Warning	PHI	Chester, Delaware	9 hr
Aug 4, 2:09 PM EDT	Areal Flood Warning	PHI	Berks, Chester, Delaware, Montgomery, Philadelphia	15 hr
Aug 4, 2:23 PM EDT	River Flood Warning	PHI	Lehigh	16 hr
Aug 4, 4:39 PM EDT	River Flood Warning	PHI	Monroe	6 hr
Aug 4, 7:29 PM EDT	Areal Flood Warning	PHI	Lehigh, Northampton	12 hr
Aug 4, 4:50 AM EDT	Tornado Warning	PHI	Sussex	25 min
Aug 4, 7:39 AM EDT	Tornado Warning	PHI	Sussex	36 min
Aug 4, 7:51 AM EDT	Tornado Warning	PHI	Sussex	24 min
Aug 4, 8:15 AM EDT	Tornado Warning	PHI	Kent	45 min
Aug 4, 8:18 AM EDT	Tornado Warning	PHI	Sussex	27 min
Aug 4, 8:27 AM EDT	Tornado Warning	PHI	Kent	33 min
Aug 4, 8:56 AM EDT	Tornado Warning	PHI	Kent, New Castle	34 min
Aug 4, 8:58 AM EDT	Flash Flood Warning	PHI	Kent, New Castle, Sussex	3 hr
Aug 4, 9:06 AM EDT	River Flood Warning	PHI	New Castle	11 hr
Aug 4, 9:23 AM EDT	Flash Flood Warning	PHI	New Castle	4 hr
Aug 4, 10:38 AM EDT	River Flood Warning	PHI	New Castle	14 hr
Aug 4, 12:27 PM EDT	River Flood Warning	PHI	New Castle	10 hr
Aug 4, 12:48 PM EDT	River Flood Warning	PHI	New Castle	24 hr

Nearby

Areal Flood Advisories in New Jersey, 2020 Areal Flood Advisories in Pennsylvania, 2020 Areal Flood Advisories in Delaware, 2020 Every areal flood advisory 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.