Flash Flood in Pennsylvania, September 7, 1999

Name: Flash Flood in Pennsylvania, September 7, 1999
Start: 1999-09-07T00:01
End: 1999-09-07T06:00
Location: Pennsylvania

September 7, 1999 · NWS CTP · 1 event in 1 county or zone

1 flash flood, as filed by the National Weather Service.

Where it happened

Every event with a place to put it; 1 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

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The toll

Deaths: 0
Injuries: 0
Property damage: $10 million
Crop damage: None recorded
Events: 1

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 radar

The national radar mosaic for the moment the first event began.

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Event by event

1 flash flood. Local standard time, as filed.

Flash Flood, Union

When: September 7, 12:01 AM EST to 6:00 AM EST
Where: Union County, East Portion
Property damage: $10 million
Reported by: EMERGENCY MANAGER
Coordinates: 40.963, -77.062 (the zone’s center; the record gives no point)

The city of Lewisburg was especially hard hit by the remnants of Hurricane Dennis as up to 8 inches of rain fell in 24 hours, most of it during the early morning hours. Waters rose rapidly in the early morning hours. At least 160 people were displaced from their homes, many of them Bucknell University students. A total of 414 homes were affected by the flooding along with 30 county businesses. Vehicles were floated down the city side streets and 162 were damaged. The campus of Bucknell University also had damage. Other parts of the county from Mifflinburg east to the Susquehanna River had problems. Route 15, the major north/south highway to Harrisburg, was closed due to flooding.

What these are

Flash Flood: Flooding that begins within six hours of the rain that causes it, or of a dam or levee failure or ice jam release, often with deadly speed.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Pennsylvania in 1999 Every state in 1999 This day in weather history Warnings in Pennsylvania, September 1999

Sources

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 2026-09-24. Each event’s entry at NCEI: 5722709.