A slow moving warm front resulted in areas of dense fog across the middle Delaware Valley early on February 23rd. A cold frontal passage during the mid-morning cleared the fog out.
Every event with a place to put it; 5 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS PHI wrote it up.
A slow moving warm front resulted in areas of dense fog across the middle Delaware Valley early on February 23rd. A cold frontal passage during the mid-morning cleared the fog out.
The local office's own words before the first event, 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 the first event at Feb 22, 6:35 PM EST, 5 hours 25 minutes earlier.
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</html>The national radar mosaic for the moment the first event began.
5 dense fog. Local standard time, as filed.
Several hours of dense fog was observed at Trenton Mercer Airport and Doylestown Airport.
Several hours of dense fog was observed at Quakertown Airport, Perkasie Airport and Doylestown Airport.
Several hours of dense fog was observed at Lehigh Valley International Airport.
Several hours of dense fog was observed at Lehigh Valley International Airport.
Several hours of dense fog was observed at Pocono Mountains Municipal Airport.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Pennsylvania in 2023Every state in 2023This day in weather historyWarnings in Pennsylvania, February 2023
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-10-01. Each event’s entry at NCEI: 1079523, 1079524, 1079525, 1079526, 1079527.