Alert archive / New Jersey / Dense Fog Advisories in 2020

Dense Fog Advisory 3, NWS Philadelphia/Mount Holly

February 26, 20204 counties in New Jersey; Chester County, Pennsylvania; Kent County, New Castle County, Sussex County, Delaware

NWS Philadelphia/Mount Holly issued this dense fog advisory at Feb 26, 2020, 12:53 AM EST for 4 counties in New Jersey; Chester County, Pennsylvania; Kent County, New Castle County, Sussex County, Delaware. It was in force for 8 hr.

The area

The counties it named.

The facts

Issued
Feb 26, 2020, 12:53 AM EST (05:53 UTC)
Expired
Feb 26, 2020, 9:00 AM EST
In force
8 hr
Issued by
NWS Philadelphia/Mount Holly

Counties Kent County, DE, New Castle County, DE, Sussex County, DE, Atlantic County, NJ, Cape May County, NJ, Cumberland County, NJ, Salem County, NJ, Chester County, PA

The radar

The Dover AFB radar (KDOX), 60 km from the middle of the area, began a volume at 05:50 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, 5.9 hours before the alert went out and 189 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-pSkew-T log-p diagram, Washington/Dulle, VA at 00:00Z on 2020-02-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2 joules per kilogram.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Washington/Dulle, VA at 00:00Z on 2020-02-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 41 square meters per square second.1939587897117136156175Sfc1 km3 km6 km9 kmRMLM
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
2 J/kg
Mixed-layer CIN
0 J/kg
Mixed-layer LCL
542 m above ground
0-6 km bulk shear
61 kt
0-1 km storm-relative helicity
41 m²/s²
0-3 km storm-relative helicity
99 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 Feb 25, 9:34 PM EST, 3 hours 19 minutes earlier.

Area forecast discussion, Feb 25, 9:34 PM EST, 3 hours 19 minutes before
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The office that day

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

IssuedProductOfficeCountiesLasted
Feb 26, 12:54 AM ESTMarine Dense Fog AdvisoryPHI8 hr
Feb 26, 2:40 PM ESTGale WarningPHI37 hr

Nearby

Dense Fog Advisories in New Jersey, 2020Dense Fog Advisories in Delaware, 2020Dense Fog Advisories in Pennsylvania, 2020Every dense fog 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.