Radiational cooling under high pressure combined with lingering low-level moisture from recent precipitation resulted in several hours of dense freezing fog across eastern Pennsylvania early on March 1st. The fog dissipated shortly after sunrise.
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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.
Radiational cooling under high pressure combined with lingering low-level moisture from recent precipitation resulted in several hours of dense freezing fog across eastern Pennsylvania early on March 1st. The fog dissipated shortly after sunrise.
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 28, 9:10 PM EST, 2 hours 50 minutes earlier.
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</html>The national radar mosaic for the moment the first event began.
3 dense fog, 3 freezing fog. Local standard time, as filed.
Several hours of dense freezing fog was observed at Reading Regional Airport.
Several hours of dense freezing fog was observed at Queen City Airport.
Several hours of dense freezing fog was observed at Lehighton Airport.
Several hours of dense freezing fog was observed at Reading Regional Airport.
Several hours of dense freezing fog was observed at Queen City Airport.
Several hours of dense freezing fog was observed at Lehighton 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, March 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: 1080540, 1080541, 1080542, 1080543, 1080544, 1080545.