Easterly flow and a moist air mass under high pressure allowed areas of dense fog to form late on June 28th and early on June 29th. 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.
Easterly flow and a moist air mass under high pressure allowed areas of dense fog to form late on June 28th and early on June 29th. 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 Jun 28, 7:43 PM EST, 1 hour 17 minutes earlier.
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</html>The national radar mosaic for the moment the first event began.
4 dense fog. Local standard time, as filed.
Several hours of dense fog was observed at Brandywine Regional Airport.
Several hours of dense fog was observed at Chester County Airport.
Several hours of dense fog was observed at Wings Field Airport.
Several hours of dense fog was observed at Quakertown Airport and Pennridge Airport.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Pennsylvania in 2026Every state in 2026This day in weather historyWarnings in Pennsylvania, June 2026
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: 1341199, 1341200, 1341201, 1341202.