Alert archive / New Jersey / Dense Fog Advisories in 2025

Dense Fog Advisory 4, NWS Philadelphia/Mount Holly

May 14, 202511 counties in New Jersey; 5 counties in Pennsylvania

NWS Philadelphia/Mount Holly issued this dense fog advisory at May 14, 2025, 8:16 PM EDT for 11 counties in New Jersey; 5 counties in Pennsylvania. It was in force for 13 hr.

The area

The counties it named.

The facts

Issued: May 14, 2025, 8:16 PM EDT (00:16 UTC)
Expired: May 15, 2025, 9:00 AM EDT
In force: 13 hr
Issued by: NWS Philadelphia/Mount Holly

Counties Atlantic County, NJ, Burlington County, NJ, Camden County, NJ, Cape May County, NJ, Cumberland County, NJ, Gloucester County, NJ, Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ, Ocean County, NJ, Salem County, NJ, Bucks County, PA, Chester County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 46 km from the middle of the area, began a volume at 00:17 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

Washington/Dulle, VA (KIAD), launched 00:00Z, 0.3 hours before the alert went out and 236 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: 366 J/kg
Mixed-layer CIN: 0 J/kg
Mixed-layer LCL: 577 m above ground
0-6 km bulk shear: 11 kt
0-1 km storm-relative helicity: 45 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 dense fog 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 dense fog advisory went out at May 14, 7:59 PM EDT, 17 minutes earlier.

Area forecast discussion, May 14, 7:59 PM EDT, 17 minutes before

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In the hours before

Local storm report, May 14, 5:31 PM EDT, 2 hours 45 minutes before

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Local storm report, May 14, 5:38 PM EDT, 2 hours 38 minutes before

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Local storm report, May 14, 5:53 PM EDT, 2 hours 23 minutes before

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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, May 14, 6:06 PM EDT, 2 hours 10 minutes before

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      <h1 id="headline">This service is currently unavailable.</h1>
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        The site you requested is temporarily down for maintenance or an unexpected outage.
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      <p id="message2">
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Local storm report, May 14, 8:01 PM EDT, 15 minutes before

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      <p id="message2">
        Please try again in a few minutes.
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      <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, May 14, 8:16 PM EDT, 0 minutes before

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<body>
  <main class="wrap">
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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.
      </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
May 15, 9:34 AM EDT	Coastal Flood Advisory	PHI	Burlington	46 hr
May 15, 4:56 PM EDT	Flash Flood Warning	PHI	Burlington, Mercer, Monmouth	44 min

Nearby

Dense Fog Advisories in New Jersey, 2025 Dense Fog Advisories in Pennsylvania, 2025 Every dense fog advisory in 2025

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.