Pennsylvania, 2000

Flash Flooding in Pennsylvania, December 17, 2000

December 17, 2000 · NWS PHI · 2 events in 2 counties and zones

An unseasonably warm air mass and an intense low pressure system and cold front not only set the stage for an extremely windy day, but also produced heavy rain and flooding across the Lehigh Valley. A series of showers and thunderstorms with heavy downpours moved across the region during the first half of the 17th.

Where it happened

Every event with a place to put it; 2 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
None recorded
Crop damage
None recorded
Events
2

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.

What happened

The episode as NWS PHI wrote it up.

An unseasonably warm air mass and an intense low pressure system and cold front not only set the stage for an extremely windy day, but also produced heavy rain and flooding across the Lehigh Valley. A series of showers and thunderstorms with heavy downpours moved across the region during the first half of the 17th. The Lehigh Valley was located between the bands of heaviest rains that affected the Poconos and the northwest Philadelphia suburbs. Nevertheless Doppler Radar storm total estimates averaged between 1.5 and 3.0 inches.The heavy rain caused urban and poor drainage flooding and also led to the flooding of some of the streams in the valley.In Lehigh County, emergency personnel were busy pumping flooded basements, rescuing stranded motorists and barricading roads made impassable by water. This included Pennsylvania State Route 309 in Alburtis Borough. In Allentown, two families were evacuated because of fear of a roof collapse. Also within Allentown, the Cedar Creek flooded, partially submerging trucks in a parking lot. In Northampton County, the Bushkill Creek flooded in both Palmer and Bushkill Townships. Roadblocks were set up on several roadways. In Bethlehem, The Monocacy Creek flooded Center Street and the industrial quarter of the city. The creek also flooded in Allen and East Allen Township and caused more road closures. Storm totals included 3.49 inches in Bath (Northampton County), 2.84 inches in Easton (Northampton County) and 2.28 inches at the Lehigh Valley International Airport

The radar

The Philadelphia radar (KDIX), 125 km away, was scanning. The volume nearest the first event began at 12:57 UTC.

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Event by event

2 flash flood. Local standard time, as filed.

Flash Flood, Lehigh

When
December 17, 8:00 AM EST to 12:00 PM EST
Where
Lehigh County, Countywide
Reported by
NEWSPAPER
Coordinates
40.613, -75.592 (the zone’s center; the record gives no point)

Flash Flood, Northampton

When
December 17, 8:00 AM EST to 12:00 PM EST
Where
Northampton County, Countywide
Reported by
NEWSPAPER
Coordinates
40.754, -75.307 (the zone’s center; the record gives no point)

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

More

Every storm in Pennsylvania in 2000Every state in 2000This day in weather historyWarnings in Pennsylvania, December 2000

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: 5167990, 5167991.