Alert archive / Pennsylvania / Flash Flood Watches in 2016

Flash Flood Watch 6, NWS Pittsburgh, PA

October 20, 201614 counties in Pennsylvania; 9 counties in West Virginia; 11 counties in Ohio

NWS Pittsburgh, PA issued this flash flood watch at Oct 20, 2016, 11:45 AM EDT for 14 counties in Pennsylvania; 9 counties in West Virginia; 11 counties in Ohio. It took effect at Oct 20, 2016, 4:00 PM EDT. It was in force for 16 hr.

The area

The counties it named.

The facts

Issued: Oct 20, 2016, 11:45 AM EDT (15:45 UTC)
In effect from: Oct 20, 2016, 4:00 PM EDT
Expired: Oct 21, 2016, 8:28 AM EDT
In force: 16 hr
Issued by: NWS Pittsburgh, PA
Flood severity: None

All 34 counties

Belmont County, OH, Carroll County, OH, Columbiana County, OH, Coshocton County, OH, Guernsey County, OH, Harrison County, OH, Jefferson County, OH, Monroe County, OH, Muskingum County, OH, Noble County, OH, Tuscarawas County, OH, Allegheny County, PA, Armstrong County, PA, Beaver County, PA, Butler County, PA, Clarion County, PA, Fayette County, PA, Forest County, PA, Greene County, PA, Jefferson County, PA, Lawrence County, PA, Mercer County, PA, Venango County, PA, Washington County, PA, Westmoreland County, PA, Brooke County, WV, Hancock County, WV, Marion County, WV, Marshall County, WV, Monongalia County, WV, Ohio County, WV, Preston County, WV, Tucker County, WV, Wetzel County, WV

The radar

The Pittsburgh radar (KPBZ), 28 km from the middle of the area, began a volume at 15:49 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

Pittsburgh, PA (KAGC), launched 12:00Z, 3.8 hours before the alert went out and 28 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: 45 J/kg
Mixed-layer CIN: -141 J/kg
Mixed-layer LCL: 1215 m above ground
0-6 km bulk shear: 61 kt
0-1 km storm-relative helicity: 278 m²/s²
0-3 km storm-relative helicity: 264 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 watch went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Pittsburgh, PA wrote its last area forecast discussion before this flash flood watch went out at Oct 20, 10:48 AM EDT, 57 minutes earlier.

Area forecast discussion, Oct 20, 10:48 AM EDT, 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>

Hazardous weather outlook, Oct 20, 8:31 AM EDT, 3 hours 14 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, Oct 20, 6:47 AM EDT, 4 hours 58 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, Oct 20, 7:12 AM EDT, 4 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>

Local storm report, Oct 20, 7:59 AM EDT, 3 hours 46 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, Oct 20, 8:02 AM EDT, 3 hours 43 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 Pittsburgh, PA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Oct 20, 2:11 AM EDT	Special Weather Statement	PBZ	Beaver	34 min
Oct 20, 2:36 AM EDT	Special Weather Statement	PBZ	Allegheny, Washington	39 min
Oct 20, 6:23 AM EDT	Flash Flood Warning	PBZ	Mercer	4 hr
Oct 20, 4:51 PM EDT	Severe Thunderstorm Warning	PBZ	Greene	39 min
Oct 20, 5:11 PM EDT	Special Weather Statement	PBZ	Allegheny	34 min
Oct 20, 5:27 PM EDT	Severe Thunderstorm Warning	PBZ	Fayette, Greene, Washington	25 min
Oct 20, 5:30 PM EDT	Special Weather Statement	PBZ	Armstrong	30 min
Oct 20, 6:07 PM EDT	Special Weather Statement	PBZ	Indiana	23 min
Oct 20, 6:10 PM EDT	Special Weather Statement	PBZ	Fayette	35 min
Oct 20, 6:24 PM EDT	Severe Thunderstorm Warning	PBZ	Indiana, Jefferson	36 min
Oct 20, 6:42 PM EDT	Severe Thunderstorm Warning	PBZ	Fayette, Westmoreland	33 min
Oct 20, 4:19 PM EDT	Severe Thunderstorm Warning	PBZ	Wetzel	41 min
Oct 20, 12:10 AM EDT	Special Weather Statement	PBZ	Muskingum	35 min

Nearby

Flash Flood Watches in Pennsylvania, 2016 Flash Flood Watches in Ohio, 2016 Flash Flood Watches in West Virginia, 2016 Every flash flood watch in 2016

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.