Alert archive / Pennsylvania / Areal Flood Warnings in 2026

Areal Flood Warning 16, NWS Philadelphia/Mount Holly

August 20, 2026Montgomery County, Philadelphia County, Pennsylvania

NWS Philadelphia/Mount Holly issued this areal flood warning at Aug 20, 2026, 9:45 PM EDT for Montgomery County, Philadelphia County, Pennsylvania. 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 20, 2026, 9:45 PM EDT (01:45 UTC)
Expired: Aug 21, 2026, 12:43 AM EDT
In force: 3 hr
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Flood severity: None

Counties Montgomery County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 74 km from the middle of the area, began a volume at 01:46 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.

What forecasters said that day

The local office's own words before this areal flood warning 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 warning went out at Aug 20, 9:18 PM EDT, 27 minutes earlier.

Area forecast discussion, Aug 20, 9:18 PM EDT, 27 minutes before

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Hazardous weather outlook, Aug 20, 5:12 AM EDT, 16 hours 33 minutes before

Hazardous Weather Outlook
National Weather Service Mount Holly NJ
512 AM EDT Thu Aug 20 2026

MDZ012-015-019-020-210915-
Kent MD-Queen Annes-Talbot-Caroline-
512 AM EDT Thu Aug 20 2026

This Hazardous Weather Outlook is for northeast Maryland.

.DAY ONE...Today and tonight.

Numerous thunderstorms are expected between about 2 PM and 8 PM. These
storms may contain damaging wind gusts and potentially a couple of
tornadoes over the Eastern Shore. Storms will be capable of producing
heavy rainfall, with rainfall rates of 2 to 4" per hour possible.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

The probability for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

Hoeflich

In the hours before

Local storm report, Aug 20, 9:12 PM EDT, 33 minutes before

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Local storm report, Aug 20, 9:13 PM EDT, 32 minutes before

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Local storm report, Aug 20, 9:14 PM EDT, 31 minutes before

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      <p id="message2">
        Please try again in a few minutes.
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        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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Local storm report, Aug 20, 9:17 PM EDT, 28 minutes before

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<body>
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      <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.
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Local storm report, Aug 20, 9:33 PM EDT, 12 minutes before

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<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.
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Local storm report, Aug 20, 9:42 PM EDT, 3 minutes before

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<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>
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The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 20, 8:32 PM EDT	Special Marine Warning	PHI		118 min
Aug 20, 9:07 PM EDT	Small Craft Advisory	PHI		11 hr
Aug 20, 9:37 PM EDT	Special Marine Warning	PHI		53 min
Aug 21, 12:43 AM EDT	Areal Flood Warning	PHI	Philadelphia	2 hr

Nearby

Areal Flood Warnings in Pennsylvania, 2026 Every areal flood warning in 2026

Sources

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