Oregon, 2015

Heavy Rain in Oregon, October 31, 2015

October 31, 2015 · NWS PQR · 2 events in 2 counties and zones

A slow moving cold front associated with an atmospheric river of subtropical moisture produced heavy rain across Northwest Oregon that resulted in urban flooding for the Portland metro area. High rain rates and clogged drains (from shedding of tree leaves) contributed to the flooding.

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
$200,000
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 PQR wrote it up.

A slow moving cold front associated with an atmospheric river of subtropical moisture produced heavy rain across Northwest Oregon that resulted in urban flooding for the Portland metro area. High rain rates and clogged drains (from shedding of tree leaves) contributed to the flooding.

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 Portland, OR wrote its last area forecast discussion before the first event at Oct 31, 8:30 AM PST, 4 hours 30 minutes earlier.

Area forecast discussion, Oct 31, 8:30 AM PST, 4 hours 30 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

2 heavy rain. Local standard time, as filed.

Heavy Rain, Multnomah

When
October 31, 1:00 PM PST to 8:00 PM PST
Where
Multnomah County, Gresham to 2 mi WSW of Portland
Property damage
$150,000
Reported by
County Official
Coordinates
45.500, -122.430

Heavy rain combined with clogged drains from leaves resulted in urban flooding. The Portland Fire and Rescue received 32 calls in regards to street flooding, and assisted travelers in 5 cars from their stalled or trapped cars to dry land. Four roads were closed in the area for high water, and several Max lines were cancelled due to flooding under bridges. Thirteen Max trains were damaged by water and will be out of service for up to 2 weeks. One roof collapsed from the weight of rain water after the roof drains had been clogged, and several homes or businesses had flooded basements. A tree had fallen onto and damaged a parked car.

Heavy Rain, Washington

When
October 31, 1:00 PM PST to 7:00 PM PST
Where
Washington County, 0.5 mi NE of Beaverton to 1 mi W of Hillsboro
Property damage
$50,000
Reported by
Emergency Manager
Coordinates
45.485, -122.813

Heavy rain combined with clogged drains resulted in small stream and urban flooding. There were 16 instances where water or agricultural debris needed to be cleared from roadways. At least two residential basements were flooded in Beaverton. A large basement of an office building was flooded in Hillsboro.

What these are

Heavy Rain
Rainfall totals unusual for the place and season that did not produce a flood.

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

The same day elsewhere

More

Every storm in Oregon in 2015Every state in 2015This day in weather historyWarnings in Oregon, October 2015

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: 601425, 601426.