Pennsylvania, 2007

Flooding in Pennsylvania, October 27, 2007

October 27, 2007 · NWS PHI · 5 events in 5 counties and zones

A slow moving weather pattern gave eastern Pennsylvania four days of rainy weather which culminated with periods of heavy rain from the afternoon of the 26th into the morning of the 27th. 5 to 5 inches across most the area with the highest amounts across the Philadelphia northwest suburbs.

Where it happened

Every event with a place to put it. 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

Open the live radar over this ground

The toll

Deaths
0
Injuries
0
Property damage
None recorded
Crop damage
None recorded
Events
5

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.

A slow moving weather pattern gave eastern Pennsylvania four days of rainy weather which culminated with periods of heavy rain from the afternoon of the 26th into the morning of the 27th. Four day storm totals averaged 2.5 to 5 inches across most the area with the highest amounts across the Philadelphia northwest suburbs. This caused poor drainage flooding as well as flooding of some of the smaller creeks in and around the local Philadelphia area. Specific storm totals included 5.74 inches in Norristown (Montgomery County), 4.76 inches in Doylestown (Bucks County), 4.11 inches in West Chester (Chester County), 3.73 inches in Chadds Ford (Delaware County), 3.33 inches in Walnutport (Northampton County), 3.20 inches in Lehighton (Carbon County), 3.00 inches in Mount Pocono (Monroe County), 2.97 inches in Reading (Berks County), 2.93 inches at the Lehigh Valley International Airport and 2.86 inches at the Philadelphia International Airport.

The heavy rain was caused by a long and continuous fetch of tropical moisture between a slow moving upper level low from the south central part of the United States and a blocking ridge over the western Atlantic. The closed system lifted into the Great Lakes on Saturday the 27th and permitted a cold front to move through the region that day and shut off the moisture connection from the tropics.

What forecasters said that day

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 Oct 27, 3:30 AM EST, 3 hours 38 minutes earlier.

Area forecast discussion, Oct 27, 3:30 AM EST, 3 hours 38 minutes before
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Hazardous weather outlook, Oct 27, 4:00 AM EST, 3 hours 8 minutes before
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In the hours before

Special weather statement, Oct 27, 3:55 AM EST, 3 hours 13 minutes before
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The radar

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

Open the radar archive at this moment

Event by event

5 flood. Local standard time, as filed.

Flood, Delaware

When
October 27, 7:08 AM EST to 11:48 AM EST
Where
Delaware County, 1.14 mi SSE of Edgemont to 1.19 mi S of Edgemont
Cause
Heavy Rain
Reported by
Mesonet
Coordinates
39.956, -75.418

Crum Creek at Newtown Square was above its 6 foot flood stage from 818 a.m. EDT through 1248 a.m. EDT on the 27th. It crested at 6.71 feet at 930 a.m. EDT. Storm totals within the county since precipitation started falling on Wednesday the 24th included 3.73 inches in Chadds Ford and 3.58 inches in Media.

Flood, Montgomery

When
October 27, 8:26 AM EST to 3:48 PM EST
Where
Montgomery County, 1.74 mi NE of Graterford to 1.05 mi ENE of Oreland
Cause
Heavy Rain
Reported by
Mesonet
Coordinates
40.250, -75.430

The heavy rain caused flooding along sections of the East Branch of the Perkiomen Creek and Wissahickon Creek in Montgomery County. The Wissahickon Creek at Fort Washington was above its 9 foot flood stage from 926 a.m. EDT through 448 p.m. EDT on the 27th. It crested at 10.22 feet at 245 p.m. EDT. The East Branch of the Perkiomen Creek near Schwenksville was above its 7 foot flood stage from 112 p.m. EDT through 415 p.m. EDT on the 27th. It crested at 7.20 feet at 230 p.m. EDT. Some poor drainage flooding also occurred in Norristown. Storm totals within the county since precipitation started falling on Wednesday the 24th included 5.74 inches in Norristown, 4.36 inches in King of Prussia, 3.90 inches in Wynnewood, 3.49 inches in Graterford and 3.40 inches in Palm.

Flood, Chester

When
October 27, 10:59 AM EST to 12:15 PM EST
Where
Chester County, 1.23 mi W of Valley Forge to 1.21 mi N of Cedar Hollow Station
Cause
Heavy Rain
Reported by
Mesonet
Coordinates
40.100, -75.493

The Valley Creek at Valley Forge was above its 7 foot flood stage from 1159 a.m. EDT through 115 p.m. EDT on the 27th. It crested at 7.39 feet at 1230 p.m. EDT. Storm totals within the county since precipitation started falling on Wednesday the 24th included 4.11 inches in West Chester, 4.04 inches in Valley Forge, 4.03 inches in London Grove. 3.88 inches in Longwood Gardens and 3.58 inches in East Nantmeal Township.

Flood, Philadelphia

When
October 27, 11:15 AM EST to 8:08 PM EST
Where
Philadelphia County, 1.31 mi ESE of Manayunk to 1.27 mi ESE of Manayunk
Cause
Heavy Rain
Reported by
Mesonet
Coordinates
40.013, -75.207

The Wissahickon Creek at its mouth with the Schuylkill River was above its 5 foot flood stage from 1115 a.m. EDT through 908 p.m. EDT on the 8th. It crested at 5.63 feet at 645 p.m. EDT. Storm totals within Philadelphia since precipitation started falling on Wednesday the 24th included 3.06 inches at the Northeast Philadelphia Airport and 2.83 inches at the Philadelphia International Airport.

Flood, Bucks

When
October 27, 2:07 PM EST to 7:53 PM EST
Where
Bucks County, 0.43 mi S of Langhorne to 0.39 mi SSE of Langhorne
Cause
Heavy Rain
Reported by
Mesonet
Coordinates
40.164, -74.949

The Neshaminy Creek at Langhorne was above its 9 foot flood stage from 307 p.m. EDT through 853 p.m. EDT on the 27th. It crested at 9.49 feet at 6 p.m. EDT. Storm totals within the county since precipitation started falling on Wednesday the 24th included 4.76 inches in Doylestown, 4.09 inches in Furlong, 3.55 inches in Neshaminy Falls and 3.08 inches in Springtown.

What these are

Flood
Flooding that develops more slowly than a flash flood: rivers leaving their banks, or water standing over land for an extended time.

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

The same day elsewhere

More

Every storm in Pennsylvania in 2007Every state in 2007This day in weather historyWarnings in Pennsylvania, October 2007

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 2026-10-01. Each event’s entry at NCEI: 62887, 62894, 62896, 62884, 62889.