Alert archive / New Jersey / Dense Fog Advisories in 2025

Dense Fog Advisory 5, NWS Philadelphia/Mount Holly

May 15, 202516 counties in New Jersey; 10 counties in Pennsylvania; Kent County, New Castle County, Sussex County, Delaware

NWS Philadelphia/Mount Holly issued this dense fog advisory at May 15, 2025, 9:34 PM EDT for 16 counties in New Jersey; 10 counties in Pennsylvania; Kent County, New Castle County, Sussex County, Delaware. It was in force for 12 hr.

The area

The counties it named.

The facts

Issued: May 15, 2025, 9:34 PM EDT (01:34 UTC)
Expired: May 16, 2025, 10:01 AM EDT
In force: 12 hr
Issued by: NWS Philadelphia/Mount Holly

All 29 counties

Kent County, DE, New Castle County, DE, Sussex County, DE, Atlantic County, NJ, Burlington County, NJ, Camden County, NJ, Cape May County, NJ, Cumberland County, NJ, Gloucester County, NJ, Hunterdon County, NJ, Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ, Morris County, NJ, Ocean County, NJ, Salem County, NJ, Somerset County, NJ, Sussex County, NJ, Warren County, NJ, Berks County, PA, Bucks County, PA, Carbon County, PA, Chester County, PA, Delaware County, PA, Lehigh County, PA, Monroe County, PA, Montgomery County, PA, Northampton County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 59 km from the middle of the area, began a volume at 01:39 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 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 15, 9:08 PM EDT, 26 minutes earlier.

Area forecast discussion, May 15, 9:08 PM EDT, 26 minutes before

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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, 9:30 PM EDT	Marine Dense Fog Advisory	PHI		15 hr
May 16, 11:16 AM EDT	Severe Thunderstorm Warning	PHI	Camden, Gloucester	59 min
May 16, 11:32 AM EDT	Flash Flood Warning	PHI	Burlington, Camden, Gloucester, Mercer, Salem	4 hr
May 16, 11:41 AM EDT	Special Marine Warning	PHI		49 min
May 16, 11:46 AM EDT	Severe Thunderstorm Warning	PHI	Cumberland, Gloucester, Salem	59 min
May 16, 12:20 PM EDT	Severe Thunderstorm Warning	PHI	Camden, Cumberland, Gloucester, Salem	40 min
May 16, 12:22 PM EDT	Tornado Warning	PHI	Cumberland, Salem	23 min
May 16, 12:31 PM EDT	Flash Flood Warning Considerable damage threat	PHI	Camden, Gloucester	4 hr
May 16, 12:42 PM EDT	Tornado Warning	PHI	Atlantic, Cape May, Cumberland	48 min
May 16, 12:45 PM EDT	Tornado Warning	PHI	Atlantic, Camden, Gloucester	30 min
May 16, 12:47 PM EDT	Flash Flood Warning Considerable damage threat	PHI	Burlington, Camden, Gloucester, Salem	4 hr
May 16, 12:49 PM EDT	Severe Thunderstorm Warning Considerable damage threat	PHI	Atlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 1 more	56 min
May 16, 12:51 PM EDT	Special Marine Warning	PHI		114 min
May 16, 12:52 PM EDT	Tornado Warning	PHI	Atlantic, Camden, Gloucester	23 min
May 16, 1:26 PM EDT	Severe Thunderstorm Warning	PHI	Cape May, Cumberland	49 min
May 16, 1:28 PM EDT	Flash Flood Warning	PHI	Burlington, Ocean	3 hr
May 16, 1:32 PM EDT	Special Marine Warning	PHI		88 min
May 16, 1:36 PM EDT	Flash Flood Warning Considerable damage threat	PHI	Atlantic, Cape May, Ocean	3 hr
May 16, 1:58 PM EDT	Severe Thunderstorm Warning	PHI	Cape May	32 min
May 16, 2:01 PM EDT	Special Marine Warning	PHI		86 min
May 16, 2:24 PM EDT	Areal Flood Warning	PHI	Hunterdon, Somerset	94 min
May 16, 6:31 PM EDT	Special Marine Warning	PHI		119 min
May 16, 6:35 PM EDT	Severe Thunderstorm Warning Considerable damage threat	PHI	Cape May, Cumberland, Gloucester, Salem	70 min
May 16, 10:24 AM EDT	Severe Thunderstorm Warning	PHI	Berks, Bucks, Carbon, Chester, Lehigh, Monroe and 2 more	66 min
May 16, 11:22 AM EDT	Severe Thunderstorm Warning	PHI	Bucks, Chester, Montgomery, Philadelphia	53 min
May 16, 11:41 AM EDT	Flash Flood Warning	PHI	Chester, Delaware	4 hr
May 16, 12:21 PM EDT	Flash Flood Warning	PHI	Bucks, Montgomery	4 hr
May 16, 2:02 PM EDT	River Flood Warning	PHI	Chester	5 hr
May 16, 3:29 PM EDT	Areal Flood Warning	PHI	Berks	6 hr
May 16, 3:53 PM EDT	Areal Flood Warning	PHI	Montgomery	100 min
May 16, 4:42 PM EDT	Areal Flood Warning	PHI	Montgomery, Philadelphia	4 hr
May 16, 5:15 PM EDT	Areal Flood Warning	PHI	Bucks	112 min
May 16, 6:43 PM EDT	Areal Flood Warning	PHI	Philadelphia	113 min
May 16, 1:52 PM EDT	Tornado Warning	PHI	Sussex	38 min
May 16, 2:18 PM EDT	Severe Thunderstorm Warning	PHI	Sussex	42 min
May 16, 2:23 PM EDT	Tornado Warning	PHI	Sussex	52 min
May 16, 6:56 PM EDT	Tornado Warning	PHI	Sussex	34 min

Nearby

Dense Fog Advisories in New Jersey, 2025 Dense Fog Advisories in Pennsylvania, 2025 Dense Fog Advisories in Delaware, 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; radar from the NEXRAD Level II archive.